National Climate Report - April 2020

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National Overview

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April Highlights

April Temperature

• During April, the average contiguous U.S. temperature was 50.9°F, 0.2°F below the 20^th century average. This ranked in the middle third of the 126-year period of record.
• Above-average temperatures were observed across much of the West Coast and Southwest as well as portions of the Gulf Coast and Florida. Florida ranked sixth warmest on record for April.
• Miami experienced its warmest April on record with an average temperature of 81.9°F. The previous record was 80.4°F set in 2015. In fact, April 2020 was warm enough to rank fifth warmest among all average temperature values on record for May.
• A large portion of the contiguous U.S., from the northern Rockies to the Great Lakes and from the southern Plains to the Northeast, experienced below-average temperatures.
• The contiguous U.S. average maximum (daytime) temperature during April was 63.7°F, 0.2°F above the 20^th century average, ranking in the middle third of the record. Above-average maximum temperatures were observed from the Pacific Northwest to the Southwest and along the Gulf Coast. Florida ranked 11^th warmest April for daytime temperatures. Below-average maximum temperatures were observed from the southern Plains to the Great Lakes and into New England, as well as in parts of the northern Plains.
• The contiguous U.S. average minimum (nighttime) temperature during April was 38.1°F, 0.5°F below the 20^th century average, ranking in the middle third of the historical record. Above-average conditions were observed again from the Pacific Northwest to the Southwest and along portions of the Gulf Coast and extreme Southeast. Record overnight warmth was concentrated in southern Florida, which contributed to Florida's rank of sixth warmest for overnight temperatures. Below-average minimum temperatures were observed from the Northern Rockies and Plains to the Great Lakes and to the southern Plains and Tennessee Valley as well as across parts of the Northeast.
• The Alaska April temperature was 27.5°F, 4.2°F above the long-term average. This ranked in the warmest third of the 96-year period of record for the state. On average, the North Slope, West Coast, Bristol Bay and Aleutian divisions had temperatures that were much-above average, while the southeast mainland and Panhandle regions were near to below average for the month.
• Utqiaġvik reported a record low temperature of −20°F on April 29. This is the first record low temperature reported at this station since December 21, 2007, and is the latest in the season with a low temperature of −20°F or colder.
• Bering Sea ice cover for April was greater than the extent observed in both 2018 and 2019, but was still fourth lowest on record.
• During April there were nearly 1.5 times as many cold daily records as compared with warm records. As of May 6, there were 2,848 record warm daily high (1,257) and low (1,591) temperature records and 4,112 record cold daily high (2,014) and low (2,098) temperature records.
• Based on NOAA's Residential Energy Demand Temperature Index (REDTI), the contiguous U.S. temperature-related energy demand during April was 124 percent of average and ranked 40^th highest in the 126-year period of record.

April Precipitation

• The April precipitation total for the contiguous U.S. was 2.47 inches, 0.05 inch below average, and ranked in the middle third of the 126-year period of record.
• Above-average precipitation was observed across parts of the West, lower Mississippi Valley, Great Lakes, Southeast, Mid-Atlantic and New England. West Virginia ranked fifth wettest while Virginia and Georgia ranked sixth wettest April on record.
• With 16.9 inches of snowfall reported on April 16, Boulder broke the record for its snowiest season. For the season and through the end of April, Boulder received 152 inches of snow, surpassing the record of 143.2 inches set in 1909.
• Below-average precipitation was observed from the Pacific Northwest to the western Great Lakes and from the Southwest through central Texas to the Canadian border. Nebraska and Colorado ranked sixth driest for April while Washington state ranked 13^th driest.
  • Salt Lake City had its driest April on record with 0.26 inch for the month, breaking the previous record of 0.45 inch set back in 1981 and 1934.
• April is climatologically either the driest or second driest month of the year across Alaska. Precipitation received during April 2020 was three to five times the average value in many locations and ranked in the wettest one-third of the historical record for the state. For some interior locations, this exacerbated an already above-average snow pack season.
• Nome received a record 2.47 inches of (liquid-equivalent) precipitation for the month of April, breaking the previous record of 2.15 inches set in 1961.
• Nome had its wettest March-April on record and Fairbanks its second wettest.
• Snowpack was at or near record levels at some locations from the upper Kuskokwim River to the Alaska Range. This helped raise water levels on some of the largest Alaskan rivers.
• According to the April 28 U.S. Drought Monitor report, 14.8 percent of the contiguous U.S. was in drought, up slightly from 14.5 percent at the end of March. Drought conditions intensified and expanded across much of the West Coast, Great Basin, and parts of the Plains and Gulf Coast. Drought improved across portions of south Texas, Hawaii, and other parts of the Gulf Coast.
• According to NOAA data analyzed by Rutgers Global Snow Lab, the April snow cover extent was approximately 32,000 square miles above the 1981-2010 average and ranked as the 22^nd largest extent in the 54-year period of record. Above-average snow cover was observed across much of the Northern Tier and central Plains as well as northern New England. Below-average snow cover was present across much of the central and southern Rockies as well as the Northeast.

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Year-to-Date Highlights

January-April Temperature

• The year-to-date (January-April) average contiguous U.S. temperature was 42.2°F, 3.0°F above average, ranking 10^th warmest on record.
• Above-average temperatures blanketed most of the Lower 48. Florida ranked warmest on record for the first four months of the year with 12 additional states from the Deep South to New England experiencing a top-five warmest January-April period.
• The contiguous U.S. average maximum (daytime) temperature during January-April was 53.1°F, 2.7°F above the 20^th century average, ranking in the warmest third of the historical record. Above-average conditions were observed across most of the Lower 48 with pockets of near-average temperatures from the Southwest to the Mississippi River. Every state except Arkansas ranked above- to much-above-average for this four-month period with Florida ranking second warmest for daytime temperatures.
• The contiguous U.S. average minimum (nighttime) temperature during January-April was 31.2°F, 3.4°F above the 20^th century average, tying with 2006 as sixth warmest on record. Above-average to record-warm conditions blanketed nearly the entire Lower 48. Florida, Georgia, South Carolina and North Carolina each ranked warmest on record.
• The Alaska January-April temperature was 8.7°F, 1.6°F below the long-term average and ranked in the coldest one-third of the record. Below-average temperatures blanketed an area from the Central Interior to the Northeast Gulf and westward into the Bristol Bay division. A small portion of the Aleutians ranked above average during this time.
• Based on REDTI, the contiguous U.S. temperature-related energy demand during January-April was 35 percent of average and was the sixth lowest value on record.

January-April Precipitation

• The year-to-date national precipitation total was 10.53 inches, 1.06 inch above average, ranking in the wettest third of the January-April record.
• Above-average precipitation stretched from parts of the Southwest to the Southeast and from the Tennessee Valley to the Great Lakes and into portions of the Northeast. Tennessee ranked wettest for this four-month period while West Virginia and Alabama ranked second and third wettest on record, respectively.
• Below-average precipitation was observed from the West Coast, across the central Rockies and into the northern Plains as well as across portions of the Gulf Coast and Florida. North Dakota ranked fourth driest for the first four months of the year, while South Dakota ranked 10^th driest.
• Harrisburg, Pennsylvania, reported its lowest seasonal snowfall total on record — second lowest for Philadelphia and Allentown, Pennsylvania; Wilmington, Delaware; and Atlantic City, New Jersey.
• San Juan, Puerto Rico, received above-average precipitation again in April. The airport received a total of 26.53 inches of precipitation for the period January-April — the wettest such period on record and 5.35 inches greater than the previous record set in 2005.
• The (March-April) snowfall total for Fairbanks, Alaska, through April 30, is 35.4 inches. This is more than four times the average amount and ties with 1963 as the third highest spring total on record. The current March-April record is held by 1918 with 40 inches of snow.

Extremes

• The U.S. Climate Extremes Index (USCEI) for the year-to-date was 39 percent above average and ranked in the highest third of the 111-year period of record. Extremes in warm maximum and minimum temperatures, wet PDSI values, and days with precipitation were the major contributors to this elevated CEI value. The USCEI is an index that tracks extremes (falling in the upper or lower 10 percent of the record) in temperature, precipitation and drought across the contiguous United States.
  • On the regional scale, The Southeast ranked highest on record for this four-month period while the Northeast ranked fourth highest. Most of the elevated to record-levels in extremes were due to large regions of warm maximum and minimum temperatures, as well as wet PDSI and days with precipitation. The Southeast also had elevated extremes in 1-day precipitation. In contast, the Northwest had below-average extremes for this year-to-date period ranking ninth lowest on record. Extremes in warm maximum temperatures were the only above-average indicator for this region during the first four months of 2020.

Regional Highlights

These regional sumapries were provided by the six Regional Climate Centers and reflect conditions in their respective regions. These six regions differ spatially from the nine climatic regions of the National Centers for Environmental Information.

Northeast Region (Information provided by the Northeast Regional Climate Center)

• The Northeast experienced its first colder-than-normal month since November 2019. The region’s average temperature of 43.4 degrees F (6.3 degrees C) was 2.7 degrees F (1.5 degrees C) below normal. All twelve states experienced a colder-than-normal April, with average temperatures ranging from 3.4 degrees F (1.9 degrees C) below normal in Rhode Island to 1.1 degrees F (0.6 degrees C) below normal in Delaware. Several major climate sites including Bridgeport and Hartford, Connecticut; Boston and Worcester, Massachusetts; Newark, New Jersey; Binghamton, Islip, and Kennedy Airport, New York, recorded their coldest highest max temperatures for April. In addition, for the first time on record, Newark did not reach 70 degrees F (21 degrees C) during the month of April. Similarly, several other sites including Hartford, Kennedy Airport, LaGuardia Airport (New York) did not record a day this April with a high of at least 70 degrees F (21 degrees C), tying as the least on record for April.
• The Northeast received 4.35 inches (110.49 mm) of precipitation in April, which was 119 percent of normal. Ten states were wetter than normal, with precipitation for all states ranging from 92 percent of normal in New York to 167 percent of normal in West Virginia, its fifth wettest April. In addition, Maryland and Massachusetts had their 19th wettest April on record. Dulles Airport, Virginia, and Erie, Pennsylvania, set or tied their greatest number of April days with measurable precipitation with 16 days and 19 days, respectively.
• A complex storm system brought severe weather and snow to the Northeast in early April. Southern parts of the region experienced severe weather from April 7 to 9. Straight-line winds of up to 80 mph (36 m/s) caused extensive damage in several locations. For example, in western West Virginia, portions of two 180-foot (55 m) communications towers were knocked over, a building at a car dealership collapsed, and the roofs of several homes were damaged or destroyed. Storm reports also indicated that hail accumulation of several inches was plowed off roads in western West Virginia. To the north, in western Pennsylvania, three weak (EF-0 or EF-1) tornadoes damaged trees and buildings, the Pittsburgh International Airport recorded its second highest thunderstorm wind gust on record at 75 mph (34 m/s), and a hangar and plane were destroyed at the Arnold Palmer Municipal Airport. As the low pressure system that produced the severe weather moved towards New England, a second low developed over the Gulf of Maine and rapidly strengthened to a near-record level for April for Maine. The result was strong wind gusts for the entire Northeast and a major late season snowstorm for parts of Maine and New Hampshire from April 9 to 10. The greatest storm snow totals approached 21 inches (53 cm). Caribou, Maine, recorded 10.9 inches (27.7 cm) of snow on April 10, making it the site’s second snowiest April day on record. The snow from the storm helped Caribou have its second longest streak with at least an inch (2.54 cm) of snow depth at 159 days (November 12, 2019 to April 18, 2020). The record of 163 consecutive days was set last year. The heavy, wet snow and strong winds downed trees and caused more than 266,000 customers in Maine, around a third of the state, to lose power. Coastal flooding occurred from New Jersey to Maine. A few days later, from April 12 to 13, another storm system produced damaging winds in the Northeast. Non-thunderstorm wind gusts of 40 to 60 mph (18 to 27 m/s) were common, with some of the highest wind gusts reaching 82 mph (37 m/s) near Lanoka Harbor, New Jersey; 80 mph (36 m/s) in Milton, Massachusetts; 79 mph (35 m/s) in Dewey Beach and Indian Beach, Delaware; and 75 mph (34 m/s) in Moosic, Pennsylvania. Across the region, the strong winds downed trees and wires and damaged homes and buildings. For instance, a roof was blown off a store in Cape May, New Jersey, and a cow barn was tossed into a power pole in Rockland, Massachusetts. Hundreds of thousands of customers lost power in the Northeast, including more than 115,000 customers in Massachusetts. The system also produced heavy rain, with the greatest totals of more than 3 inches (76 mm) reported in central Maryland, southeastern Pennsylvania, and coastal Connecticut where some flooding occurred. The combination of rain and snowmelt also caused flooding in parts of northern New England. In addition, two weak (EF-0 or EF-1) tornadoes snapped trees and damaged houses in northern Maryland. Severe thunderstorms on April 21 produced several waterspouts, one of which came onshore, and straight-line winds of up to 80 mph (36 m/s), which damaged trees, buildings, and boats in central and southern New Jersey.
• For more information, please visit the Northeast Regional Climate Center Home Page.

Midwest Region (Information provided by the Midwest Regional Climate Center)

• April precipitation varied considerably across the Midwest. Monthly precipitation totals ranged from 25 to 50 percent of normal along the Minnesota-Iowa border to nearly twice normal in central Illinois, northern Michigan, and southeastern Kentucky. Three swaths of above normal precipitation extended, from southwest to northeast, across both northwestern Minnesota and southeastern Kentucky and also from southwestern Missouri, across Illinois, to northern Michigan. Between the swaths of above normal precipitation there were two swaths of below normal precipitation. One covered northern Missouri, all of Iowa, and much of Minnesota and Wisconsin. The other extended from southeastern Missouri and western Kentucky to Lake Erie and the southern half of Lake Huron. Iowa recorded its 15th driest April since 1895 with less than 50 percent of normal precipitation statewide. Much of the region was quite dry until the last week of April when heavy rain stretched from Missouri to Michigan and also fell in eastern Kentucky and southeastern Ohio.
• Temperatures in April averaged below normal across the region. The region averaged 46.0 degrees F (7.8 C), which was 3.0 degrees F (1.7 C) below normal. All nine states were below normal for the month but there were big swings in temperatures. From April 6th to 9th, temperatures were as much as 10 degrees F (6 C) above normal, and then from April 14th to 18th, temperatures were more than 10 to 15 degrees F (6 to 8 C) below normal for most of the Midwest. More than 800 daily record low temperatures were recorded in April, with more than 180 on each of the 15th and 16th. Daily record high temperatures numbered just over 150 for the month, with nearly all of them on three days, the 7th to the 9th.
• Three snow events accounted for the majority of the snow in April. On the 3rd and 4th, snow fell in northwestern Minnesota. From the 11th to the 13th, snow fell from northwestern Iowa to Upper Michigan. And from the 15th to the 18th, snow fell from the Iowa-Missouri border eastward to the Michigan-Ohio border. All three of these areas had above-normal snowfall totals for the month. Departures from normal exceeded 8 inches (20 cm) above normal south-central Iowa and parts of Upper Michigan.
• Widespread freezing temperatures were recorded on the 15th and 16th. Frost and freeze damage was reported to early planted vegetables in Illinois and Indiana. Michigan had reports of damage to fruit trees and grape vines.
• Severe weather was reported on just 10 days in April across the region. Nearly all of the severe weather reports fell on just two days in April, the 7th and 8th. Minnesota had some reports of severe weather on the 6th, and the other eight states were all hit on the 7th, the 8th, or both days. There were seven more days with severe weather later in the month. Tornadoes were reported in Indiana, Ohio, and Kentucky on the 7th and/or 8th, with just two tornado reports later in the month, one in Indiana and one in Missouri. Hail reports were also most common on the 7th and the 8th, with large hail (greater than 2 inches (5 cm) reported in Illinois, Iowa, Michigan, Missouri, Ohio, and Wisconsin.
• The complete absence of drought in the Midwest reached 25 weeks, since mid-November of 2019. However, in the latter half of April, areas of abnormal dryness did appear for the first time since early January. The streak of 14 straight weeks without any abnormally dry areas in the region was the longest in the history of the US Drought Monitor, which began in 2000.
• As soils dried out in early to mid-April, planting accelerated across the Corn Belt. Corn planting was at 35 percent complete or higher in Kentucky, Illinois, Iowa and Minnesota according to USDA’s National Agricultural Statistics Service. Only Missouri was significantly behind, 21 percent below their five-year average. Soybeans planting quickly ramped up, with Kentucky and Illinois both at 18 percent planted by the end of April.
• For further details on the weather and climate events in the Midwest, see the weekly and monthly reports at the Midwest Climate Watch page.

Southeast Region (Information provided by the Southeast Regional Climate Center)

• Temperatures ranged from below average to average across much of the Southeast region during April, with well-above average temperatures were observed across much of the Florida peninsula. Monthly mean temperatures were within 2 degrees F (1.1 degrees C) of normal for approximately 68 percent of the 203 long-term (i.e., period of record equaling or exceeding 50 years) stations across the region. In Florida however, there were 15 stations that observed monthly mean temperatures that were ranked within their five warmest values on record, including Key West, FL (1871-2020; warmest April), Fort Myers, FL (1902-2020; warmest April), and Miami, FL (1895-2020; warmest April). This warmth is due in part to record-breaking sea surface temperatures across portions of the Gulf of Mexico and Caribbean for this time of the year. San Juan, PR (1898-2020) reported 1.1 degrees F (0.7 degrees C) above normal for the month. Maximum temperatures ranged from 6 degrees F (3.3 degrees C) above normal in Plant City, FL (1892-2020) to 5.6 degrees F (3.1 degrees C) below normal in Luray, VA (1941-2020). Likewise, daily temperature minimums ranged from 6.3 degrees F (3.5 degrees C) above normal in Miami, FL (1895-2020) to 4.5 degrees F (2.5 degrees C) below normal in Haleyville, AL (1902-2020). The warmest weather of the month occurred from the 12th through the 13th, as the circulation around the Bermuda High, situated off the Atlantic coast, transported warm, humid air over much of the Southeast region. Daily maximum temperatures exceeded 80 degrees F (26.7 degrees C) across much of the region, with portions of central and southern Florida reaching 90 degrees F (32.2 degrees C) or higher. Indeed, Orlando FL (1892-2020) had a daily maximum temperature of 97 degrees F (36.1 degrees C) which tied its 3rd warmest April day on record. In contrast, the coldest weather of the month across the Southeast occurred on the 16th and 17th, as the circulation around a departing mid-latitude cyclone ushered in unseasonably cold, dry air. Daily minimum temperatures fell below 35 degrees F (1.7 degrees C) across portions of every state north of Florida.
• Precipitation was near normal to well above normal across much of the Southeast region during April. Monthly precipitation totals ranged from 150 to more than 300 percent of normal in broad portions of every state. Seven long-term stations (i.e., period of record equaling or exceeding 50 years) observed their wettest April on record, including Macon, GA (1892-2020), which received 11.9 inches (302 mm) of precipitation, over 8.9 inches (226 mm) above normal. In contrast, the driest locations were found across southern Florida and Puerto Rico where monthly precipitation totals were 50 to less than 25 percent of normal. Key West, FL (1871-2020) only received 0.72 inches (18 mm) of precipitation for the month, 1.3 inches (33 mm) below normal. From the 19th through the 20th, a line of thunderstorms produced heavy rainfall across the central portions of Alabama and Georgia, with 24-hour precipitation totals exceeding 5 inches (127 mm) and numerous reports of localized flooding. Clanton, AL (1893-2020) reported 7.35 inches (187 mm) of rain, which ranked as its first wettest April day on record. Columbus, GA (1948-2020), and Macon, GA (1892-2020) each ranked their second wettest April day on record with 5.92 inches (150 mm) and 4.41 inches (112 mm) of rain, respectively. Snow was confined to the mountains of western North Carolina and Virginia. The CoCoRaHS station in Tazewell, VA measured 4.2 inches (107 mm) of snowfall, the highest in the region for the month, while Mt. Mitchell, NC (1980-2020) measured 3 inches (76 mm).
• There were 1186 reports of severe weather across the Southeast during April, which is 480 percent of the median monthly frequency of 247 reports during 2000-2018. There were 129 confirmed tornadoes reported for the month (35 EF-0, 66 EF-1, 17 EF-2, 10 EF-3, and 1 EF-4), over quadruple the monthly average of 28. About 99 of these tornadoes were associated with a line of thunderstorms and embedded supercells that developed ahead of a cold front, which moved across the region on April 12th – 13th. The most damaging tornado was rated an EF-4 with winds of 175 mph (78 m/s) and occurred in Hampton County, SC. This unusually long track and wide tornado damaged and destroyed many residences, including mobile and single-family homes. In addition, the tornado caused extensive damage to trees and powerlines along its path, which stretched more than 24 miles southwest of Estill, to near the Colleton County line. Tragically, there were five fatalities associated with this tornado in the hardest hit areas just south of Estill, SC. The damage pattern suggested that this tornado may have consisted of multiple vortices, which can occur with strong tornadoes. This was the first EF-4 tornado in South Carolina since 1995. An EF-2 with winds of 135 mph (60 m/s) caused the second highest number of fatalities during the outbreak with seven people killed and 23 injured in Murray County, GA. At least eight double-wide manufactured homes were destroyed, and a cell tower was crumpled from the strong winds. Another tornado developed over Huntington Beach State Park in South Carolina, on the morning of April 13th. After the tornado damaged trees and homes, it moved just off the coast becoming a strong waterspout near Murrells Inlet jetty, where a remote weather station recorded a peak wind gust of 114 mph (51 m/s). No injuries were reported. There were 15 reports of hail for the month, with the largest being hen egg-sized (2.00 inches) in Cleveland, NC. There were 927 wind reports for the month, which is six times the average (142 reports). Damaging straight line winds were observed across central Alabama on April 19th, with the strongest reported gust at 80 – 90 mph (36 - 40 m/s) in Chilton County, AL. There were numerous reports of trees down, with several of instances of damage to structures, and three injuries. Raleigh, NC has recorded 13 days with wind gusts of 30 mph (13 m/s) or higher. This is the highest count seen for any one month from 1975-2020.
• Drought has improved across Florida, southern Georgia, and southern Alabama for the month of April. Moderate drought (D1) reduced in coverage across almost the entire Florida peninsula. Although the pocket of severe drought (D2) is gone in the Florida panhandle, it has emerged in the southwestern part of the state. By the end of the month, abnormally dry conditions (D0) were eliminated in southern Georgia and most of southern Alabama, however the pocket of moderate drought (D1) remains along the Gulf Coast of Alabama. Abnormally dry conditions (D0) developed in the southern part of Puerto Rico. In Florida, pasture conditions improved and greened up from the rainfall in April. However, excess rainfall in the northern peninsula caused disease pressures on watermelons, potatoes, corn and peanuts. Citrus grove activities continued as normal for this time of year, as growers were able to spray insecticides, fertilize, mow, and irrigate. Thunderstorms, high winds, and significant rainfall in many parts of the state flooded several fields, damaged crops and delayed fieldwork for many producers throughout much of Georgia. Blueberries were badly damaged by the severe weather and hail, however strawberries and peaches in the western part of the state were looking good. Heavy rainfall kept farmers out of the fields in northern Alabama. Some emerged corn was flooded, and many farmers were waiting for the rain to pass and the ground to dry before planting cotton. However, pastures were developing very well from the rainfall.
• For more information, please visit the Southeast Regional Climate Center Home Page.

High Plains Region (Information provided by the High Plains Regional Climate Center)

• Overall, April was a cool and dry month for the High Plains region. The largest temperature departures were across the northern parts of the region, where temperatures were generally 4.0-6.0 degrees F (2.2-3.3 degrees C) below normal. Further south, temperatures were closer to normal for this time of the year, with some locations in Colorado having slightly above-normal temperatures. Meanwhile, the majority of the region was dry, with large areas of Colorado, Kansas, Nebraska, North Dakota, and South Dakota receiving less than 50 percent of normal precipitation.
• This month’s conditions had mixed impacts for agriculture. On a positive note, dry conditions helped producers get out into the fields for spring planting. This was quite the contrast to last year’s extreme wetness and delayed planting. But, the dryness, in combination with hard freezes, has begun to take a toll on the Kansas winter wheat crop. According to Kansas State University’s Agronomy eUpdates, a preliminary assessment of the winter wheat crop after freezes during the week of April 13th showed damage, especially in the central part of the state. Damage to the crop varied across western and central areas, however, due to the different growth stages of the crop and the wide range of low temperatures that occurred. Other hard freezes that week impacted the Western Slope of Colorado, which is known for its peach production. With temperatures below 28.0 degrees F (-2.2 degrees C) several nights in a row, the peach crop was decimated. A USDA Disaster Declaration has been requested for the impacted counties.
• Although dry conditions were widespread, flooding along some rivers continued to be an issue for parts of the region. In North Dakota, flooding along the Red River created significant problems as many roads and bridges were closed, including a section of I-29 between Manvel and Grafton. On April 24th, North Dakota Governor Doug Burgum declared a statewide flood emergency due to the spring flooding. In a statement released from the Office of the Governor, the initial damage to infrastructure was estimated at $7 million.
• Overall, temperatures were below normal across the High Plains region this month. Departures increased from south to north, with near-normal temperatures across portions of Colorado, Kansas, and Nebraska and departures of up to 8.0 degrees F (4.4 degrees C) below normal across northern portions of the region. This included pockets of North Dakota, South Dakota, and northeastern Wyoming. The warm spot for the month was southwestern Colorado, where temperatures were 2.0-4.0 degrees F (1.1-2.2 degrees C) above normal.
• One of the cooler locations in the region was Grand Forks, North Dakota, which had its 8th coolest April on record with an average temperature of 35.7 degrees F (2.1 degrees C) (period of record 1893-present). This was 6.3 degrees F (3.5 degrees C) below normal. On the 4th, with a minimum temperature of -5.0 degrees F (-20.6 degrees C), Grand Forks set a new temperature record for the day, beating the old record set in 1970 by 5.0 degrees F (2.8 degrees C). Although the month of April was on the cool side overall, the region experienced a wide range of temperatures. For instance, Lincoln, Nebraska set a new record high of 87.0 degrees F (30.6 degrees C) on the 7th and then set a new record low of 17.0 degrees F (-8.3 degrees C) on the 10th. Only a week later, Lincoln recorded back-to-back record low temperatures of 16.0 degrees F (-8.9 degrees C) on the 14th and 15th (period of record 1887-present). The contrast between very warm and very cold temperatures caused substantial freeze damage in some areas. Early estimates show that approximately 95% of Colorado’s peach crop may be lost due to a series of hard freezes that occurred the week of April 13th.
• April was a dry month across the High Plains region, with only a few spotty areas receiving normal or above-normal precipitation. A large swath of the region from Colorado northeastward through Kansas, Nebraska, and South Dakota had precipitation totals of less than 50 percent of normal. Embedded within this area, a few pockets received less than 5 percent of normal precipitation. This dryness led to monthly precipitation deficits of 1.50-3.00 inches (38-76 mm), which has had mixed impacts across the region. Dry conditions helped with spring planting, but the lack of moisture has begun to stress pastures and winter wheat. Ultimately, these extremely dry conditions led to several locations ranking in the top 10 driest Aprils on record, including Norfolk, NE (2nd driest); Williston, ND (4th driest); Goodland, KS (6th driest); and Alamosa, CO (7th driest).
• As mentioned above, some locations did receive above-normal precipitation, such as eastern and southern North Dakota, northern Colorado, western Wyoming, and portions of eastern Kansas. Only a few isolated areas received upwards of 200 percent of normal precipitation. Although the month was dry, there were a few locations that ranked in the top 10 snowiest Aprils on record, including Lincoln, NE (6th snowiest); Omaha, NE (6th snowiest); and Boulder, CO (6th snowiest). Boulder’s snowfall this month was particularly noteworthy as it pushed the seasonal snowfall total to 152.0 inches (386 cm) – a new record! The old record of 143.2 inches (364 cm) was set over 100 years ago during the 1908-09 season (period of record 1893-present). The storm system that pushed Boulder’s snowfall into record territory occurred during the middle of the month when a particularly strong system moved across the region, bringing a swath of late-season snowfall to portions of Colorado, Wyoming, Nebraska, and northern Kansas. Boulder had a one-day snowfall total of 16.9 inches (43 cm) on the 16th, which was the second highest one-day April snowfall on record! Other places also had impressive totals, albeit much smaller. Lincoln, NE and Omaha, NE picked up 4.5 inches (11 cm) and 5.0 inches (13 cm), respectively. Not only was this the season’s largest snowfall for both locations, it was also a top 5 single-day snowfall total for the month of April. The combination of wet, heavy, snow and strong winds did cause some damage to trees and power lines. Travel was disrupted in some areas, as a portion of I-80 was closed in Wyoming due to the wintry conditions.
• This month, drought conditions expanded only slightly across the High Plains region. According to the U.S. Drought Monitor, the area experiencing drought (D1-D4) in the region increased about 2 percent between March 31st and April 28th. Although the area in drought did not increase much, it should be noted that drought conditions intensified in Colorado, with severe drought (D2) expanding to include nearly 33 percent of the state. Abnormally dry conditions (D0) increased in coverage across much of the region this month. To the south, D0 spread across portions of eastern Colorado, Nebraska, and Kansas, while another area developed across North Dakota and South Dakota as well. The small area of D0 in west-central Wyoming, which was introduced due to a low snowpack, remained. By the end of the month, over 20 percent of the region was in the D0 designation. With precipitation deficits mounting, these areas are being closely monitored for the development of drought conditions. Meanwhile, in Colorado, drought expanded and intensified across the south and east, with over half of the state experiencing drought conditions at the end of the month. In Kansas, drought conditions remained largely unchanged, with only a slight expansion in D1 and D2 coverage. Impacts to rangelands and winter wheat have been reported in these two states. The remainder of the region was free of drought and abnormally dry conditions.
• Overall, mountain snowpack remained in decent shape during the month of April. At the end of April, the statewide snowpack for Colorado and Wyoming was 97 percent of median and 118 percent of median, respectively. In Colorado, the Snow Water Equivalent (SWE) was near or above median in the north and below median in the south, while in Wyoming, SWE was near to above median in all basins except for Belle Fourche, Cheyenne, and Sweetwater. As of April 30th, mountain SWE across the Upper Missouri Basin was right around average. According to the U.S. Army Corps of Engineers, mountain SWE was 98 percent of average above Fort Peck and 99 percent of average in the reach from Fort Peck to Garrison. Snowpack above Fort Peck peaked on April 16th at 109 percent of the normal peak, with snowpack in the reach from Fort Peck to Garrison peaking on April 19th at 112 percent of the normal peak.
• For more information, please visit the High Plains Regional Climate Center Home Page.

Southern Region (Information provided by the Southern Regional Climate Center)

• Temperatures for the month of April were below normal across much of the Southern Region. Parts of eastern, central, and southern Oklahoma; north-central Texas; central and northern Arkansas; central and northern Mississippi; and most of Tennessee experienced temperatures 2 to 4 degrees F (1.11 to 2.22 degrees C) below normal. Parts of central and southeastern Tennessee, southern and western Arkansas, central and northern Mississippi, central and northern Louisiana, central, eastern, central, and northern Texas, and most of Oklahoma experienced temperatures 0 to 2 degrees F (0.00 to 1.11 degrees C) below normal. Parts of far western Oklahoma, northern, western, southern, and southeastern Texas, southwestern and southeastern Louisiana, and southern Mississippi experienced temperatures 0 to 2 degrees F (0.00 to 1.11 degrees C) above normal, while parts of western and southern Texas as well as southeastern Louisiana experienced temperatures 2 to 4 degrees F (1.11 to 2.22 degrees C) above normal. The statewide monthly average temperatures were as follows: Arkansas – 58.80 degrees F (14.89 degrees C), Louisiana – 66.50 degrees F (19.17 degrees C), Mississippi – 62.70 degrees F (17.06 degrees C), Oklahoma – 58.00 degrees F (14.44 degrees C), Tennessee – 55.40 degrees F (13.00 degrees C), and Texas – 65.00 degrees F (18.33 degrees C). The statewide temperature rankings for April were as follows: Arkansas (thirtieth coldest), Louisiana (fifty-ninth warmest), Mississippi (fiftieth coldest), Oklahoma (thirty-eighth coldest), Tennessee (twenty-third coldest), and Texas (fiftieth warmest). The region as a whole experienced its forty-first coldest April on record. All state rankings are based on the period spanning 1895-2020.
• Precipitation values for the month of April varied spatially across the Southern Region. Parts of central and western Oklahoma as well as northern, north-central, southern, and western Texas received 50 percent or less of normal precipitation. Parts of northern, western, and southern Texas as week as southwestern Oklahoma received 25 percent or less of normal precipitation, while parts of western and southern Texas received 5 percent or less of normal precipitation. In contrast, parts of southern and eastern Texas, southern and western Arkansas, western, northern, and southeastern Louisiana, central and southern Mississippi, and eastern Tennessee received 150 percent or more of normal precipitation, while parts of eastern Texas, northern Louisiana, northeastern Mississippi and eastern Tennessee received precipitation 200 percent or more of normal. The statewide precipitation totals for the month were as follows: Arkansas – 6.19 inches (157.23 mm), Louisiana – 6.28 inches (159.51 mm), Mississippi – 7.00 inches (177.80 mm), Oklahoma – 2.90 inches (73.66 mm), Tennessee – 6.51 inches (165.35 mm), and Texas – 1.78 inches (45.21 mm). The state precipitation rankings for April were as follows: Arkansas (thirty-first wettest), Louisiana (thirty-fourth wettest), Mississippi (twenty-eighth wettest), Oklahoma (sixtieth driest), Tennessee (sixteenth wettest), and Texas (forty-fifth driest). The region as a whole experienced its thirty-seventh wettest April on record. All state rankings are based on the period spanning 1895-2020.

Drought and Severe Weather

• At the end of April, drought conditions both improved and deteriorated across the Southern Region. Exceptional drought conditions were no longer present and extreme drought conditions improved across southern and southeastern Texas. Severe drought classifications improved slightly across southern Texas, but extreme western Oklahoma experienced a slight expansion and severe drought conditions developed in southeastern Louisiana. Moderate drought classifications decreased across southern Texas, but moderate drought conditions developed or expanded across western, southeastern, and northern Texas; extreme western Oklahoma; coastal Louisiana; and southern Mississippi. There was an increase in the overall area experiencing abnormally dry conditions, despite the improvement of abnormally dry conditions across southeastern Texas and part of southern Mississippi. This is because the area experiencing abnormally dry conditions increased across southwestern and western Oklahoma, western and southern Texas, and southern Louisiana.
• In April, there were approximately 1,247 storm reports across Texas, Oklahoma, Arkansas, Tennessee, Louisiana, and Mississippi. There were 144 tornado reports, 460 hail reports, and 643 wind reports. Mississippi tallied the most tornado reports (57) while Texas tallied the most hail (187) and wind (182) reports. Texas tallied the most reports (398) while Tennessee tallied the fewest (65). Every state reported tornadoes; Oklahoma tallied more hail reports than wind reports, and every state except for Oklahoma and Tennessee reported over 100 wind reports.
• On April 3, 2020, teacup-sized hail was reported near Calliham, Texas. Also, a wind gust of 60 mph (96.56 kph) was reported near Simmons, Texas.
• On April 4, 2020, hen egg-sized hail was reported near Arroyo City, Texas.
• On April 8, 2020, two tornadoes were reported in northeastern Arkansas. Baseball-sized hail was reported near Meridian, Mississippi and Strawberry, Arkansas. Wind gusts of 58 mph (93.34 kph) were reported near Kemper Springs, Mississippi and Loretto, Tennessee, while a wind gust of 60 mph (96.56 kph) was estimated near Onalaska, Texas.
• On April 9, 2020, a tornado was reported near Hathaway, Louisiana. Hail slightly larger than golf balls was reported near Hemphill, Texas. Wind gusts of 60 mph (96.56 kph) were reported near Basile, Louisiana and Liberty Hill, Texas, while a wind gust of 76 mph (122.31 kph) was reported at the New Orleans Lakefront Airport, Louisiana. One person was injured near Jersey Village, Texas due to strong winds.
• On April 10, 2020, baseball-sized hail was reported near Crane, Texas.
• On April 11, 2020, four tornadoes were reported across Texas. Softball-sized hail was reported near Brackettville, Texas and Del Rio, Texas, while baseball-sized hail was reported near Frederick, Oklahoma. A wind gust of 64 mph (103 kph) was reported near Waco, Texas, while several wind gusts of 60 mph (96.56 kph) were reported across Texas. A wind gust of 60 mph (96.56 kph) was reported near Gould, Oklahoma as well.
• On April 12, 2020, there were approximately 64 tornado reports, 32 hail reports, and 177 wind reports across Texas, Oklahoma, Arkansas, Louisiana, Mississippi, and Tennessee. Reports indicate eight people were killed and 26 people were injured across Mississippi, Tennessee, and Louisiana as a result of tornadoes, while three people were killed by trees felled by strong winds (one each in Texas, Arkansas, and Mississippi). Wind gusts of 70 mph (112.65 kph) were reported across parts of Texas and Arkansas.
• On April 18, 2020, teacup-sized hail was reported near Trinity, Texas, while hail slightly smaller than softballs was reported near Huntsville, Texas.
• On April 19, 2020, there were approximately 16 tornado reports, 30 hail reports, and 63 wind reports across Texas, Oklahoma, Arkansas, Louisiana, and Mississippi. Reports indicate one person was killed and one person injured during an EF-4 tornado near Hurricane Creek, Mississippi. A wind gust of 63 mph (101.39 kph) was reported near Wildwood, Texas and a wind gust of 62 mph (99.78 kph) was reported near Hattiesburg, Mississippi.
• On April 20, 2020, a wind gust of 62 mph (99.78 kph) was reported near College City, Arkansas.
• On April 21, 2020, teacup-sized hail was reported near Elgin, Oklahoma while baseball-sized hail was reported near Devol, Oklahoma and Sayre, Oklahoma. A wind gust of 81 mph (130.36 kph) was reported near Ardmore, Oklahoma.
• On April 22, 2020, there were approximately 46 tornado reports, 56 hail reports, and 75 wind reports across Texas, Oklahoma, Arkansas, Louisiana, and Mississippi. Reports indicate two people (one in Arkansas, one in Louisiana) were killed due to tornadoes, while one person was injured in Mississippi due to strong winds. Baseball-sized hail was reported near Nida, Oklahoma while tennis ball-sized hail was reported near Russett, Oklahoma and Farrsville, Texas. Wind gusts of 100 mph (160.93 kph) were reported near New Hebron, Mississippi and Gwinville, Mississippi.
• On April 23, 2020, hen egg-sized hail was reported near Bennington, Oklahoma. Also, a wind gust of 68 mph (109.44 kph) was reported just offshore south of Venice, Louisiana.
• On April 24, 2020, five tornadoes were reported across Texas, Oklahoma, and Arkansas. Softball-sized hail was reported near Benton, Louisiana, while baseball-sized hail was reported near Paris, Texas. Wind gusts of 65 mph (104.61 kph) were reported near Pryor, Oklahoma and Little Rock Air Force Base, Arkansas.
• On April 25, 2020, three people were injured by an EF-1 tornado that passed near Linwood, Tennessee.
• On April 27, 2020, a wind gust of 77 mph (123.92 kph) was reported at Del Rio International Airport, Texas, while a wind gust of 75 mph (120.70 kph) was reported at Laughlin Air Force Base, Texas.
• On April 28, 2020, three tornadoes were reported in Oklahoma and one tornado was reported near Hammond, Louisiana. Hail slightly smaller than softball-sized was reported near Chickasha, Oklahoma, while several reports detailed baseball-sized hail in Oklahoma and Texas. One person was killed and another person was injured after strong winds blew a tree onto a house near Huntsville, Texas, while one person was injured after strong winds blew a tree onto a car near Lenapah, Oklahoma. A wind gust of 78 mph (125.53 kph) was reported near Richardson, Texas, a wind gust of 75 mph (120.70 kph) was reported near Tulsa, Oklahoma, and a wind gust of 73 mph (117.48 kph) was reported near Bayou Vista, Texas.
• On April 29, 2020, a wind gust of 82 mph (131.97 kph) was reported just off the Texas coast near Port O’Connor, Texas.
• For more information, please visit the Southern Regional Climate Center Home Page.

Western Region (Information provided by the Western Region Climate Center)

• Across much of the West, precipitation in April was below normal with anomalously dry conditions observed across portions of the Four Corners states (Arizona, Colorado, New Mexico, Utah) as well as in the northern Great Basin, extreme northern California, southwestern Oregon, and central Washington. In contrast, Southern California experienced wetter-than-normal conditions in April with numerous locations breaking daily precipitation records during the early part of the month. Temperatures were near normal to slightly above normal across much of the West with the exception of Montana and Wyoming where temperatures were well below historical averages. In northern California and southwestern Oregon, the combination of above-normal temperatures, below-normal snowpack and streamflows, and reports of agricultural drought impacts led to intensification of drought conditions in the Klamath River Basin. Likewise, drought conditions intensified in the eastern plains of Colorado. With the cool season coming to an end, the April 1 snow water equivalent (SWE) levels (region-level, 2-digit HUC) were below normal in California (74%), the Great Basin (90%), and the Rio Grande (90%). Above-normal SWE was observed in the Arkansas-White-Red (103%), Lower Colorado (108%), Upper Colorado (107%), Missouri (112%), and Pacific Northwest (107%) regions.
• In California, storm systems during the early part of April brought a much-needed boost to the mountain snowpack of the central and southern Sierra as well as some record-breaking rainfall accumulations to portions of Southern California. Despite the late-season storms, water year-to-date (since October 1) precipitation was below normal levels in central and northern California with the North Coast Drainage Climate Division (CD) experiencing its 4th driest October through April period on record (126-year period). According to the California Cooperative Snow Survey (April 30), the statewide snowpack was 39% of normal (as compared to 54% of normal on April 1) with the regional breakdown as follows: northern (27%), central (44%), and south (41%). Despite the poor snowpack conditions, California’s major reservoirs remained in good condition (near normal to above normal) as a result of carry-over from the previous winter with the state’s two largest reservoirs, Lake Oroville and Shasta Lake, at 87% and 94% of historical averages, respectively, by the end of the month.
• In the Pacific Northwest, drier-than-normal conditions were observed across most of the region during April with notably dry conditions (<25% of normal precipitation) in east-central Idaho, southwestern Oregon, and central Washington. As of April 1, the majority of the drainage basins in the region were observing near normal to above normal SWE with the exception of the following basins (6-digit HUC) that were below normal: Upper Columbia (87%), Deschutes (83%), Southern Oregon Coast (87%), and Klamath (75%). According to the April 28 U.S. Drought Monitor map, 11.5% of the region was experiencing drought with areas of “severe” and “extreme” drought observed in southwestern Oregon where Governor Brown passed emergency drought declarations for Curry, Jackson, and Klamath counties. Moreover, the Southwestern Valleys CD experienced its driest February through April period on record (126-year period).
• In the Intermountain West, drier-than-normal conditions prevailed across much of Arizona, Utah, Colorado, and New Mexico as well as in the northern Great Basin. In the Humboldt River Basin in northeastern Nevada, mountain snowpack conditions saw a sharp decline in SWE by the end of the month dropping from 94% of median (Apr 1) to 30% of median by April 30. In Utah, April was very dry in northern and eastern portions with Salt Lake City International Airport (AP) logging 0.26 in (6 mm; 13% of normal) of precipitation, making it the driest April on record dating back to 1928. In western Colorado, the mountain town of Telluride experienced its 3rd driest April on record dating back to 1900 with 0.45 in (11 mm) while the town of Montrose observed its 10th driest (dating back to 1895) with 0.14 in (4 mm) for the month.
• In Alaska, warmer-than-normal temperatures prevailed across North Slope (10th warmest April) and West Coast (14th warmest) CDs during April with significant temperature anomalies observed in the Northwest Arctic where the Kivalina AP observed an average temperature of 30.8°F (-0.7°C)—a +19.2°F (10.6°C) departure from normal. Statewide, Alaska experienced its 12th wettest and 15th warmest April on record and its 14th wettest October through April period on record. At a climate-division level, precipitation was well above normal in April in the Bristol Bay CD (2nd wettest), North Slope CD (3rd wettest), and West Coast CD (4th wettest) while drier-than-normal conditions prevailed in the Aleutians CD (6th driest).
• In the Hawaiian Islands, precipitation was above normal on Oahu, Molokai, Lanai, Maui, and southern portions of the Big Island. On Oahu and Molokai, Honolulu International AP logged 2.56 in (65 mm; 406% of normal) during April while Molokai AP observed 3.83 in (97 mm; 205% of normal). Conversely, drier-than-normal conditions prevailed on both the windward and leeward sides of the Big Island with Hilo International AP reporting 7.75 in (197 mm; 67% of normal) and Kona International AP 0.15 in (4 mm; 11% of normal) for the month.

Significant Events

• Record-breaking seasonal snowfall accumulation in the Colorado Front Range:Boulder, Colorado recorded its snowiest winter on record (dating back to 1893) with 152 inches (3861 mm) as well as its 6th snowiest April on record with 37.3 in (947 mm).
• Wet April in Southern California: Los Angeles International AP logged its 3rd wettest April on record (dating back to 1944) with 2.68 in (68 mm; 383% of normal) while San Diego International AP had its 2nd wettest April on record (dating back to 1939) observing 3.68 in (93 mm; 471% of normal).
• For more information, please go to the Western Regional Climate Center Home Page.

NOAA National Centers for Environmental Information, State of the Climate: National Climate Report for April 2020, published online May 2020, retrieved on May 31, 2020 from https://www.ncdc.noaa.gov/sotc/national/.