National Climate Report - December 2014
NCEI added Alaska climate divisions to its nClimDiv dataset on Friday, March 6, 2015, coincident with the release of the February 2015 monthly monitoring report. For more information on this data, please visit the Alaska Climate Divisions FAQ.
Maps and Graphics
Temperature and Precipitation Ranks
U.S. Percentage Areas
Supplemental December 2014 Information
- Year-to-date temperature evolution for select U.S. cities
- Year-to-date precipitation evolution for select U.S. cities
- 2014 temperature and precipitation records and near records
- 2014 drought improvements
- Climate Highlights — December
- The average contiguous U.S. temperature during December was 37.1°F, 4.5°F above the 20th century average. This was the second warmest December on record for the contiguous U.S., behind December 1939 when the temperature was 37.7°F. The average maximum (daytime) December temperature was 45.7°F, 2.9°F above average and the 17th warmest on record. The average minimum (nighttime) temperature was 28.6°F, 6.0°F above the 20th century average, the warmest December contiguous U.S. minimum temperature on record. The previous record warm December minimum temperature was 26.8°F in 1994.
- Every state in the Lower 48 had an above-average December temperature. Nine states across the West, Southern Plains, and Northeast had a top 10 warm December, but no state was record warm. Minimum (nighttime) temperatures were generally warmer across most of the country, with Massachusetts and Oklahoma having record warm December minimum temperatures.
- Alaska had its fifth warmest December on record, capping off a record warm year for the state. The December statewide average temperature was 8.1°F above the 1971-2000 average. Fairbanks and McGrath had their warmest December on record, while Anchorage had the second warmest year in its 101-year record. December was drier than average in Alaska with a monthly precipitation total 19.2 percent below average.
- During December there were more than 8 times more warm daily maximum and minimum temperature records compared to cold daily maximum and minimum temperature records. There were 5,060 warm daily temperature records (1,371 maximum and 3,689 minimum) compared to 580 cold daily temperature records (370 maximum and 210 minimum).
- The December precipitation total for the contiguous U.S. was 2.51 inches, 0.16 inch above the 20th century average. This ranked near the median value in the 120-year period of record.
- Above-average precipitation was observed in the West, Central Rockies, Central Plains, parts of the Southeast, and the Northeast. Maine had its seventh wettest December on record with 6.12 inches of precipitation, 2.59 inches above average. The above-average precipitation in the West, particularly California, only marginally improved drought conditions. Long-term deficits, dating back over three years, remain quite large across the state.
- Below-average precipitation was observed in the Southern Plains and parts of the Lower Mississippi River Valley. Below-average precipitation was also observed in the Northern Plains, where North Dakota had its ninth driest December with 0.16 inch of precipitation, 0.33 inch below average.
- According to the 30 December U.S. Drought Monitor report, 28.7 percent of the contiguous U.S. was in drought. This was down slightly from 29.1 percent at the beginning of December, and was the smallest drought footprint of 2014 and the smallest since December 2011. Drought conditions marginally improved across the West, where beneficial precipitation fell, but long-term precipitation deficits persist. Drought also improved in the Southeast and Northeast. Drought conditions worsened across parts of the Southern Plains, Lower Mississippi River Valley, and parts of the Northern Plains.
- According to NOAA data analyzed by the Rutgers Global Snow Lab, the monthly snow cover extent across the contiguous U.S during December was 980,000 square miles, about 201,000 square miles below the 1981-2010 average. This was only slightly larger than the record large November extent and ranked as the 14th smallest December snow cover extent in the 49-year satellite record for the contiguous United States. This was the smallest December snow cover extent for the Lower 48 since 2011.
- Based on NOAA's Residential Energy Demand Temperature Index (REDTI), the contiguous U.S. temperature-related energy demand during November was 90 percent below average and the sixth lowest in the 1895-2014 period of record.
- Detailed information on 2014 climate conditions across the United States can be found in our annual report.
**A comparison of the national temperature departure from average as calculated by NCDC's operational dataset (nClimDiv), the U.S. Historical Climatology Network (USHCN), and the U.S. Climate Reference Network (USCRN) is available on our National Temperature Index page.**
Alaska Temperature and Precipitation:
- Alaska had its 5th warmest December since records began in 1918, with a temperature 8.15°F (4.53°C) above the 1971-2000 average.
- Alaska had its 2nd warmest October-December since records began in 1918, with a temperature 5.63°F (3.13°C) above the 1971-2000 average.
- Alaska had its 1st warmest January-December since records began in 1918, with a temperature 4.04°F (2.24°C) above the 1971-2000 average.
- Alaska had its 30th driest December since records began in 1918, with an anomaly that was -19.25% below the 1971-2000 average.
- Alaska had its 18th driest October-December since records began in 1918, with an anomaly that was -19.12% below the 1971-2000 average.
- Alaska had its 46th driest January-December since records began in 1918, with an anomaly that was 2.47% above the 1971-2000 average.
For additional details about recent temperatures and precipitation across the U.S., see the Regional Highlights section below and visit the Climate Summary page. For information on local temperature and precipitation records during the month, please visit NCDC's Records page.
These regional summaries 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 Climatic Data Center.
- Northeast Region: (Information provided by the Northeast Regional Climate Center)
- The last month of the year proved to be a warm one in the Northeast. The region's average temperature of 32.5 degrees F (0.3 degrees C) was 4.0 degrees F (2.2 degrees C) above normal, making it the 11th warmest December since 1895. All twelve Northeast states ranked this December among their top 20 warmest. Rankings were: Rhode Island, 6th warmest; Massachusetts, 7th warmest; New Hampshire and Maine, 8th warmest; Vermont, 11th warmest; Connecticut, 12th warmest; New York and New Jersey, 13th warmest; Delaware, 14th warmest; Maryland, 15th warmest; Pennsylvania, 16th warmest; and West Virginia, 17th warmest. Departures ranged from 3.3 degrees F (1.8 degrees C) above normal in Maryland to 4.8 degrees F (2.7 degrees C) above normal in New Hampshire. The year 2014 wrapped up on the cool side of normal for the Northeast. The region's average temperature of 46.3 degrees F (7.9 degrees C) was 0.9 degrees F (0.5 degrees C) below normal. All twelve states were cooler than normal during 2014, with departures ranging from 0.1 degrees F (0.1 degrees C) below normal in Maine to 1.5 degrees F (0.8 degrees C) below normal in Pennsylvania.
- December brought wetter-than-normal conditions back to the Northeast. The region picked up 3.98 inches (101.09 mm) of precipitation, 114 percent of normal. Nine of the twelve Northeast states were wetter than normal, with three ranking this December among their top 20 wettest: Maine, 7th wettest; New Hampshire, 18th wettest; and Vermont, 19th wettest. Departures for the wet states ranged from 102 percent of normal in Delaware and New York to 164 percent of normal in Maine. Departures for the dry states ranged from 88 percent of normal in Pennsylvania to 94 percent of normal in Maryland. The Northeast finished the year 2014 with 44.82 inches (1138.43 mm) of precipitation, 100 percent of normal. All states saw near-normal precipitation, with departures ranging from 90 percent of normal in Connecticut to 110 percent of normal in Maine (the state's 18th wettest year on record).
- At the start of December, 19 percent of the Northeast was abnormally dry and 2 percent of the region was experiencing moderate drought, according to the U.S. Drought Monitor. Dryness eased in New England and West Virginia by the end of the month. However, dry conditions were introduced in western and northern New York and lingered in other parts of the Northeast. Overall, 13 percent of the region was abnormally dry as of December 31.
- A slow-moving low pressure system brought a wintry mix to the Northeast from December 9 to 11. Snow totals of around 24 inches (61 cm) were reported in upstate New York and Vermont, while parts of the Mid-Atlantic saw up to 1/4 inch (6.35 mm) of ice and coastal areas of Maine and Massachusetts picked up 4 to 6 inches (102 to 152 mm) of rain. Travel disruptions were the biggest impact from the storm. On the 9th, 120 crashes were reported during the morning commute in Connecticut, while coastal areas of New Jersey, New York, and Massachusetts experienced road closures due to flooding. On the 10th, dangerous travel conditions and disabled vehicles prompted the shutdown of Interstate 81 and a tractor-trailer ban on major highways in central New York for several hours. In addition, hundreds of flights were delayed or cancelled region-wide during the storm. Looking at the 35 major Northeast airport climate sites, Kennedy Airport, NY, had its wettest December on record, while Huntington, WV, had its least snowy December on record.
- For more information, please go to the Northeast Regional Climate Center Home Page.
- Midwest Region: (Information provided by the Midwest Regional Climate Center)
- December temperatures across the Midwest region by state ranged from 3.3 degrees F (1.8 C) above normal in Kentucky to 6.6 degrees F (3.7 C) above normal for the month into Minnesota. For the region, December was 4.5 degrees F (2.5 C) above normal. The largest temperature impacts were felt across Minnesota and Iowa. Iowa came in at 5.5 degrees F (3.1 C) above average, with above normal temperatures on all but two days between the 4th and 28th. Periods averaging more than 10 degrees F (5.6 C) above normal (12th - 15th and 21st - 26th) brought overnight low temperatures frequently higher than typical daytime high temperatures. In Minnesota, numerous records were set for maximum overnight temperatures. Additional temperature records were set across northern Illinois, north-central Indiana, and central Michigan on December 16th. December 2014 ranks as the 16th warmest December on record for the region, ranging from the 13th warmest in Minnesota to the 26th warmest in Kentucky.
- December's precipitation primarily fell as rain across much of the region resulting in below normal accumulated snowfall values. This resulted in more snowfall being recorded during November rather than in December across much of the region. Total monthly accumulated precipitation was concentrated along the Ohio River Valley with observed values of 3.00 to 4.00 inches (76 to 102 mm) across southern Illinois, Indiana, Ohio, and most of Kentucky primarily from events on December 1st, 2nd, and 6th. Additional areas of higher precipitation were located across northern Wisconsin, the Upper Peninsula of Michigan, and far northern Minnesota, south of Lake of the Woods. These areas saw precipitation at 100 percent to 200 percent of normal. The remaining central, far southern, and far northwest portions of the region recorded precipitation at 25 percent to 75 percent of normal for the month. December regional precipitation was 0.40 inches (11 mm) below normal, ranking December 2014 as the 36th driest in 120 years of records. Kentucky experienced the largest precipitation departure from normal ending the month 1.06 inches (27 mm) below normal, primarily in the western half of the state were accumulated precipitation was only 50-75 percent of average. Wisconsin saw the closest to normal observed precipitation with a deficit of only 0.06 inches (2 mm); however, it was primarily concentrated in the northern half of the state.
- On Christmas Eve December 24, 2014 a weak linear convective system ahead of a cold front resulted in wind damage and a brief EF0 tornado in central Ohio (Fairfield County).
- December 17-18th, 2014: 1.00 to 3.00 inches (2.54 to 7.62 cm) of snowfall fell over Missouri potentially breaking 24 hour snowfall records.
- Abnormally dry conditions persisted in much of Minnesota (expect for far southeast counties and east-central counties) through December despite having the second smallest departure from normal precipitation in December. The dry conditions stem from below normal precipitation beginning in September 2014.
- For details on the weather and climate events of the Midwest, see the weekly summaries in the Midwest Climate Watch page.
- Southeast Region: (Information provided by the Southeast Regional Climate Center)
- Mean temperatures in December were slightly above average across much of the Southeast region. The greatest departures were found across the mountainous areas of Georgia, the Carolinas, and Virginia, where monthly temperatures were up to 5 degrees F (2.8 degrees C) above average. Mean daily maximum temperatures were 2 to 4 degrees F (1.1 to 2.2 degrees C) above average over this region, while mean daily minimum temperatures were 5 to 8 degrees F (2.8 to 4.4 degrees C) above average. Several locations within this region recorded their third warmest average minimum temperature for December, including North Wilkesboro, NC (1955-2014) and Blacksburg, VA (1952-2014). In addition, Washington, DC (1872-2014) observed its fifth warmest average minimum temperature on record for December. Mean temperatures were near average in Puerto Rico and the U.S. Virgin Islands during December. The warmest weather occurred on the 24th of the month, as moist tropical air surged northward ahead of an approaching cold front. Daily maximum temperatures exceeded 60 degrees F (15.6 degrees C) across the entire region with the exception of the Appalachian Mountains; portions of central and southern Florida reached the middle 80s F (28.9 to 30 degrees C). In contrast, the coolest weather of the month occurred during the 10th and 11th, as a continental polar air mass pushed southward across the region. Excluding Virginia, daily mean temperatures were 5 to 8 degrees F below average across much of the region, with departures exceeding 10 degrees F (5.6 degrees C) below average over central and southern Florida.
- Precipitation was highly variable across the Southeast during December. The wettest locations were found across portions of central Alabama, southwestern Georgia, and north-central Florida. Monthly precipitation departures exceeded 2 inches (50.8 mm) above normal for most locations in these areas, with a few locations surpassing 4 inches (101.6 mm) above normal. One of the wettest locations was Tallahassee, FL (1896-2014), which observed its fifth wettest December on record with 8.78 inches (223 mm) of precipitation. A large proportion of this monthly total occurred on the 23rd, when Tallahassee recorded its wettest 1-day total for December with 7.44 inches (189 mm) of precipitation. This 1-day precipitation total is nearly 200 percent of the average total precipitation for the entire month of December at this location. In contrast, the driest locations were found across central and southern Florida, where monthly precipitation ranged between 5 and 50 percent of normal. Fort Myers, FL (1902-2014) tied its fourth driest December on record with only 0.05 inches (1.3 mm) of precipitation. Precipitation was near average for much of Puerto Rico and the U.S. Virgin Islands, though Aibonito, PR (1906-2014) observed its third driest December on record with only 1.3 inches (33 mm) of precipitation. Very little snowfall was recorded across the region throughout December, with only 3.1 inches (78.7 mm) observed at Mount Mitchell, NC during the month.
- There were only 36 severe weather reports across the Southeast throughout December, and all but two of these reports occurred during a three-day severe weather outbreak from the 22nd to the 24th. In addition, all but one severe weather report occurred in the southern portion of the region (AL, GA, FL). Over 70 percent of the monthly reports were for damaging thunderstorm winds. The most significant of these events occurred on the 24th, when a vigorous squall line produced damaging straight-line winds across portions of southern Georgia and northern Florida. A woman in Thomasville, GA was injured in her car by a fallen tree. Following an NFL football game on the 21st, a lightning strike injured eleven people in the parking lot of Raymond James Stadium in Tampa, FL. Four tornadoes were confirmed across the Southeast in December, including 1 EF-0, 2 EF-1s, and 1 EF-2. Valdosta, GA was struck by two tornadoes in the span of just six days. An EF-0 briefly touched down near the city on the 23rd, and an EF-2 caused significant damage to a lumber manufacturing plant on the 29th, resulting in nine injuries. On the 24th, an EF-1 tornado touched down near Castle Hayne, NC and caused one injury due to flying glass.
- A nearly complete elimination of drought conditions was noted for the Southeast region during December. The percentage of the region under drought-free conditions (less than D1) increased from 96 percent on the 2nd to 99 percent on the 30th. The small areas of moderate (D1) drought in extreme southwestern and east-central portions of Georgia dissipated. Moderate-to-severe (D1-D2) drought conditions were alleviated in east-central Alabama, and only a small portion of coastal Alabama centered on Mobile Bay remained in moderate drought by the end of the month. Agricultural impacts were relatively minimal across the region. In Florida, the initial harvesting of sugarcane, strawberries, citrus, and vegetables was aided by modest rainfall and relatively warm temperatures. Winter pasture conditions for grazing livestock also continued to improve across portions of the state.
- For more information, please go to the Southeast Regional Climate Center Home Page.
- High Plains Region: (Information provided by the High Plains Regional Climate Center )
- December was generally mild across the High Plains Region. Much above normal temperatures for most of the month gave way to bitter cold at the end. This resulted in monthly temperatures which were above normal for the majority of the Region. Temperature departures of 2.0-6.0 degrees F (1.1-3.3 degrees C) above normal were common, however an area encompassing eastern Colorado, northwestern Kansas, and central Nebraska had temperatures which averaged out to near normal (2.0 degrees F (1.1 degrees C) above/below normal). Although not record breaking, there were some isolated areas which had departures over 6.0 degrees F (3.3 degrees C). The relative warmth placed many locations in the top 25 warmest Decembers on record. For instance, Fargo, North Dakota had an average temperature of 21.1 degrees F (-6.1 degrees C), which was an impressive 7.0 degrees F (3.9 degrees C) above normal. This ranked as the 12th warmest December on record (period of record 1881-2014). The warmest December occurred back in 1959 with an average temperature of 25.9 degrees F (-3.4 degrees C). A look at daily temperatures shows that many interesting records occurred this month. For instance, relatively warm and humid conditions settled into the Region during the middle of the month which allowed for a smaller diurnal temperature range than usual and some locations set new records for highest minimum temperature ever recorded in December. Lincoln, Nebraska had one of these records with a minimum temperature of 53 degrees F (11.7 degrees C) on the 14th. This was 37 degrees F (20.6 degrees C) above normal and high enough to beat the old record of 51 degrees F (10.6 degrees C) set on December 1, 1962. Laramie, Wyoming also had some interesting temperatures this month. With records going back to 1948, Laramie tied for its coldest December temperature with -34 degrees F (-36.7 degrees C) on the 31st and also tied for its 2nd warmest December temperature of 60 degrees F (15.6 degrees C) on the 12th. That's a 94 degree F (52.3 degree C) temperature range for the month!
- December was generally a wet month for the High Plains Region with the main exception being North Dakota. Although there was a slow start to the snow season, end of the month snowpack was near normal in the Rockies in Colorado and Wyoming, with statewide snowpacks of 103 percent and 107 percent, respectively. Additionally, a large area of the Region had precipitation totals which were greater than 200 percent of normal including central Wyoming, eastern Colorado, western Kansas, western and central Nebraska, and southern South Dakota. A few localized areas had greater than 400 percent of normal precipitation. Meanwhile in North Dakota, precipitation was lacking with widespread precipitation totals of less than 25 percent of normal. For this part of the country, liquid equivalent precipitation is typically light at this time of the year so although there were extremes, the actual amounts were quite low. These precipitation extremes led to some top 10 rankings on both ends of the spectrum. On the wet side, Scottsbluff, Nebraska had its snowiest December on record with 25.3 inches (64 cm). This new record was easily set by exceeding the old record (18.2 inches (46 cm) in 2007) by over 6.0 inches (15 cm). 9.3 inches (24 cm) fell on the 25th and was Scottsbluff's snowiest Christmas on record (period of record 1893-2014). Some areas of North Dakota, however, had a lack of snowfall this December. For example, Fargo, North Dakota only had a Trace of snow on the ground on Christmas and has yet to receive its first 1-inch (3 cm) snowfall of the season (although smaller snowfall events under one inch have occurred). Only two other times has the first 1-inch snowfall happened so late in Fargo - January 22, 1914 and January 27, 1944. With only 0.9 inches (2 cm) of snow, Fargo tied for its 3rd least snowiest December on record (period of record 1885-2014). This was 10.3 inches (26 cm) below normal.
- According to the U.S. Drought Monitor, drought conditions remained largely unchanged over the past month. Winter is typically the driest time of year, so drought improvements or developments are not usually expected and impacts of drought, if any, are minor. The total area in drought (D1-D4) remained at about 11 percent with only a very slight expansion of moderate drought (D1) in South Dakota and a slight contraction in severe drought (D2) in northwestern Kansas. Drought conditions in the southern part of the region, across Colorado and Kansas, persisted. Abnormally dry conditions (D0) have expanded westward in the Dakotas and northward in Kansas where dryness has been occurring over the past three months. According to the U.S. Seasonal Drought Outlook released December 18th, drought conditions in the small area of the Dakotas and across Kansas through eastern Colorado are expected to persist through the end of March. Although no drought areas are expected to improve or be removed, new areas of development are not expected either.
- For more information, please go to the High Plains Regional Climate Center Home Page.
- Southern Region: (Information provided by the Southern Regional Climate Center)
- December was a warmer than normal month for the Southern Region. All six states in the region reported an above average state-wide temperature. The majority of stations reported average temperature anomalies of 2 to 4 degrees F (1.11 to 2.22 degrees C) above normal. In central Texas, it was slightly warmer, with most stations reporting 4 to 6 degrees F (2.22 to 3.33 degrees C) above average. The state-wide average temperatures for the month are as follows: Arkansas reported 43.80 degrees F (6.56 degrees C), Louisiana reported 53.90 degrees F (12.17 degrees C), Mississippi reported 50.40 degrees F (10.22 degrees C), Oklahoma reported 42.20 degrees F (5.67 degrees C), Tennessee reported 42.90 degrees F (6.05 degrees C), and Texas reported 50.90 degrees F (10.50 degrees C). For Texas, it was the eighth warmest December on record (1895-2014), while for Mississippi, it was the nineteenth warmest December on record (1895-2014). Oklahoma and Tennessee experienced their twenty-first and twenty-second warmest December (1895-2014), respectively. It was also the twenty-fifth warmest December on record (1895-2014) for Louisiana and the thirty-second warmest December on record (1895-2014) for Arkansas.
- With the exception of a few spots, December was a drier than normal month across the Southern Region. Precipitation totals were well above average in the South Texas and Lower Valley climate divisions. Precipitation totals there varied between 130-200 percent of normal. Positive anomalies also occurred in east-central Mississippi with stations averaging between one and half and two times that of normal. Similar values were also observed in Parishes just north of Lake Ponchartrain in Louisiana. Conversely, conditions were quite dry in northern Texas, central Texas and south western Oklahoma. A bulk of the stations in these areas averaged only between 5 to 50 percent of normal. It was also a very dry month for Arkansas and wester Tennessee, where most stations only received between 50 and 75 percent of their normal monthly precipitation. This was also the case though most of Louisiana and north western Mississippi. The state-wide average precipitation totals are as follows: Arkansas recorded 2.91 inches (73.91 mm), Louisiana recorded 3.99 inches (101.35 mm), Mississippi recorded 5.51 inches (139.95 mm), Oklahoma recorded 1.38 inches (35.05 mm), Tennessee recorded 4.53 inches (115.06 mm), and Texas recorded 1.16 inches (29.46 mm). Louisiana experienced their twenty-seventh driest December on record (1895-2014), while for Arkansas, it was the twenty-eighth driest on record (1895-2014). All other state rankings fell within the two middle quartiles.
- Due to dry conditions in the north western corner of the Southern Region, drought conditions over northern Texas and Oklahoma remained relatively unchanged. Conversely, wetter than normal conditions in east central Mississippi has helped replenish soils and subsequently alleviate drought conditions there.
- On December 15, three tornadoes were reported in south western Mississippi. No injuries or fatalities were reported. Some minor damage was reported.
- A cold front that passed on December 23 resulted in some severe weather, with several tornadoes in south eastern Louisiana and Southern Mississippi. Three fatalities and approximately fifty injuries were reported in Marion County, Mississippi, and another two people were reported dead in Jones County, Mississippi.
- In Texas, the drought has caused many rice farmers to lose their jobs. In order to fix this problem, an additional reservoir is going to be made in Lake City. The new reservoir will be the size of the Marble Falls and Lady Bird area lakes combined. Some ranchers still have to look to other sources of income, due to their cattle struggling in the prolonged drought. Some have even had to move their cattle northward, starting back in 2011. There are currently only 3.91 million cows in Texas as of 2014 compared to the 5.35 million cows in 2005. Drought conditions tended to worsen over the course of the month, though changes from last month were not large. Dallas area reservoirs were at 62.3% of capacity, compared to 61.6% at the beginning of the month. The Mineral Wells area is making plans to install a reverse osmosis well in order to have enough water, costing $6 million. If they did not do this, the county might run out of water by spring. Population growth is still a concern for reservoir use moving forward, and there are concerns about the $2 billion SWIFT initiative's ability to combat this (Information provided by the Texas Office of State Climatology).
- For more information, please go to the Southern Regional Climate Center Home Page.
- Western Region: (Information provided by the Western Region Climate Center)
- A series of storms brought beneficial precipitation to drought-stricken areas such as California, eastern Oregon, southern Idaho, and the Great Basin this month. Throughout the West, temperatures averaged above normal despite an outbreak of very cold air over the last few days of the month.
- Average December temperatures across much of the West were more than 3 F (1.6 C) above normal. The greatest departures from normal average temperature were observed in southern Idaho and surrounding areas. Pocatello, Idaho recorded an average 32.2 F (0.1 C) for the month, the 7th warmest December in a 76-year record. To the south, Salt Lake City recorded a December average of 37.3 F (2.9 C), 7 F (3.8 C) above normal. This was the 3rd warmest December in Salt Lake since records began in 1928. Near the Idaho-Oregon border, Ontario, Oregon, observed an average of 36.2 F (2.3 C) this month, 8.4 F (4.6 C) above normal and the 3rd warmest since records began in 1945. Further west, average temperatures in California were also well above normal. In California's Central Valley, Fresno recorded its warmest December in a 67-year record with an average 51.9 F (11.0 C). This was also the warmest calendar year on record at Fresno. In northern California, Mount Shasta observed an average 41.1 F (5.1 C), 6.0 F (3.3 C) above normal and the 2nd warmest December since records began in 1948. Calendar year 2014 was by a very large margin (1.8 F/1.0 C) the warmest on record since 1895 for California (61.5 F/16.4 C), also warmest for Arizona (62.3 F/16.8 C), and Nevada (53.0 F/11.7 C), and the second warmest for Oregon (49.6 F/9.8 C).
- Several areas of the West received above normal precipitation this month. A series of storm systems during the first half of the month brought significant precipitation to California and the Pacific Northwest and helped to alleviate drought conditions in localized areas. San Francisco recorded 11.7 inches (297 mm) this month, 257% of normal and the 5th wettest December in a 166-year record. Further south, Monterey, California observed its wettest December on record with 8.9 in (226 mm). This is 380% of normal and 2.76 in (70 mm) greater than the previous record set in 2002. Records at Monterey began in 1968. In southern California, San Diego recorded 4.5 in (114 mm), 294% of normal and the 6th wettest in a 76-year record. Unfortunately, snow levels were generally high during these storms thus did not contribute significantly to the development of Sierra Nevada and Cascade snowpack. At month's end, Sierra Nevada snow water equivalent (SWE) stood at 40-60% of normal. The southern Cascades were generally in the 30-40% of normal SWE range. The northern Cascades saw SWE values in roughly the 40-70% of normal range. Further east, mountain ranges of the northeastern Great Basin and the Rocky Mountains ended the month with near to above normal SWE. Many locations in the Rocky Mountain states also recorded above normal precipitation this month. Helena, Montana logged 0.81 in (21 mm), 203% of normal and 12th wettest in a 77-year record. In central Wyoming, Lander recorded 1.82 in (46 mm) precipitation. This is 313% of normal and the 2nd wettest since records began in 1946. The Southwest saw areas of above normal precipitation as well. Flagstaff, Arizona observed 3.44 in (87 mm) this month, 184% of normal. Despite above normal precipitation in many areas this month, 54% of the West is experiencing moderate to exceptional drought. A large area of drought improvement was seen in northern California this month as well as small areas of improvement elsewhere in California, Oregon and Washington. Extreme to exceptional drought persists in a large area of California, western Nevada, and southeast Oregon.
- Precipitation across Hawaii was generally below normal. In southwestern Oahu, Kalaeloa received 0.76 in (19 mm) precipitation, 22% of normal. On the Big Island, Hilo received 6.10 in (155 mm), 53% of normal. At month's end, 29% of the state was abnormally dry and 3% was in moderate drought. Further north, temperatures throughout Alaska were warmer than normal. The greatest departures from normal were observed in the Southcentral and Interior regions. Fairbanks (8.0 F/-13.3 C) and McGrath (10.7 F/-11.8 C) both observed their warmest average December temperatures on record. Records in Fairbanks and McGrath began in 1929 and 1941, respectively. Anchorage reported its second warmest December in a 101-year record at an average 25.3 F (-3.7 C). Precipitation was variable across the state, though much of the Southcentral and Southeast regions observed below normal precipitation.
- December 12: Landslide in Camarillo, California: Following a heavy precipitation event, the hillside above a Camarillo neighborhood gave way and left 13 homes uninhabitable. A brush fire occurred in the region in 2013 and destroyed much of the vegetation that previously anchored the soil. Approximately 9 miles (14 km) away from the landslide, mudslides closed the Pacific Coast Highway and trapped several drivers. Minor flooding and associated damage was also observed elsewhere in the state.
- December 30-31: Snow in southern California mountains prompts driver rescues: Heavy snow in the San Bernadino Mountains prompted the rescue of over 100 drivers on the evening of the 30th on Highway 138. Several other mountain highways in the region experienced severe traffic backups due to the storm. In some cases, motorists had to be rescued from their vehicles. Other highways, such as Interstate 15 from Los Angeles to Las Vegas, were closed due to heavy snow.
- For more information, please go to the Western Regional Climate Center Home Page.