Drought - June 2019

Issued 11 July 2019
Contents Of This Report:
Map showing Palmer Z Index
Percent Area of U.S. in Moderate to Extreme Drought, Jan 1996 to present
Map showing drought in the U.S.-Affiliated Pacific Islands and U.S. Virgin Islands

Please note that the values presented in this report are based on preliminary data. They will change when the final data are processed, but will not be replaced on these pages.


National Drought Overview

[top]


Detailed Drought Discussion


Overview


The U.S. Drought Monitor drought map valid July 2, 2019
The U.S. Drought Monitor drought map valid July 2, 2019.

The upper-level circulation during June was very active with numerous Pacific weather systems moving in the jet stream flow. But upper-level ridging early in the month, and then a northwesterly flow later in the month, over the West meant the Pacific weather systems did not contribute much precipitation to the western CONUS where the month was drier than normal. The fronts and surface lows tapped Gulf of Mexico moisture to bring above-normal precipitation to parts of the Plains to East Coast, but even here there were drier than normal areas (especially in the northern Plains to Upper Midwest). Northern portions of the Micronesia were drier than normal while southern portions were wetter than normal, and in the Caribbean, Puerto Rico and the U.S. Virgin Islands were mostly drier than normal. The circulation pattern shifted a lot, with upper-level troughs helping keep temperatures cooler than normal across much of the CONUS for the month as a whole. The cooler-than-normal temperatures helped keep evapotranspiration down. Ridging and above-normal heights over Alaska brought warmer- and drier-than-normal conditions for much of the state. Precipitation was above normal across much of Hawaii. The rains in Hawaii, southern Micronesia, the Tennessee Valley, and Southeast shrank areas of drought and abnormal dryness. The continued dry conditions expanded or intensified drought and abnormal dryness in parts of Alaska, Puerto Rico and the U.S. Virgin Islands, Pacific Northwest, and northern Plains. Drought contraction outweighed expansion this month, with the USDM-based national moderate-to-exceptional drought footprint across the CONUS shrinking from 5.3 percent of the CONUS at the end of May to 3.2 percent of the CONUS at the end of June (from 5.0 percent to 3.3 percent for the 50 States and Puerto Rico). According to the Palmer Drought Index, which goes back to the beginning of the 20th century, about 3.5 percent of the CONUS was in moderate to extreme drought at the end of June, changing very little from the end of May.

Percent area of the CONUS in moderate to exceptional drought, January 4, 2000 to present, based on the U.S. Drought Monitor

Percent area of the CONUS in moderate to exceptional drought, January 4, 2000 to present, based on the U.S. Drought Monitor.






Drought conditions at the end of June, as depicted on the July 2nd, 2019 USDM map, included the following core drought and abnormally dry areas:



Palmer Drought Index


The Palmer drought indices measure the balance between moisture demand (evapotranspiration driven by temperature) and moisture supply (precipitation). The Palmer Z Index depicts moisture conditions for the current month, while the Palmer Hydrological Drought Index (PHDI) and Palmer Drought Severity Index (PDSI) depict the current month's cumulative moisture conditions integrated over the last several months. While both the PDSI and PHDI indices show long-term moisture conditions, the PDSI depicts meteorological drought while the PHDI depicts hydrological drought. The PDSI map shows less severe and extensive drought (as well as wet spell conditions) in some parts of the country than the PHDI map because the meteorological conditions that produce drought and wet spell conditions are not as long-lasting as the hydrological impacts.

Palmer Z Index map Palmer Hydrological Drought Index map

Used together, the Palmer Z Index and PHDI maps show that short-term wet conditions occurred across parts of the Southeast, eliminating the building drought that had begun to appear as long-term drought on the May maps (PHDI maps for May and June). Short-term wet conditions in the Midwest to Northeast intensified previous long-term wet conditions. Short-term dry conditions occurred in parts of the Pacific Northwest, intensifying long-term dry conditions.



Standardized Precipitation Index


The Standardized Precipitation Index (SPI) measures moisture supply. The SPI maps here show the spatial extent of anomalously wet and dry areas at time scales ranging from 1 month to 24 months.

1-month Standardized Precipitation Index 2-month Standardized Precipitation Index 3-month Standardized Precipitation Index

6-month Standardized Precipitation Index

The SPI maps illustrate how moisture conditions have varied considerably through time and space over the last two years. Much of the Pacific Northwest, and parts of the central to northern Plains, were dry at the 1-month time scale, and parts of the Northwest and northern Plains were dry at most other time scales. Parts of the Southwest were dry at the 1-, 3-, and 24-month time scales. Much of the Southeast was dry at the 6-month time scale, and parts were dry at the 1-, 2-, and 3-month time scales. Otherwise, wet conditions dominated much of the country at the 2- to 12-month time scales, and east of the Rockies at the 1- and 24-month time scales.


9-month Standardized Precipitation Index 12-month Standardized Precipitation Index 24-month Standardized Precipitation Index



Standardized Precipitation Evapotranspiration Index


The SPI measures water supply (precipitation), while the SPEI (Standardized Precipitation Evapotranspiration Index) measures the combination of water supply (precipitation) and water demand (evapotranspiration as computed from temperature). Warmer temperatures tend to increase evapotranspiration, which generally makes droughts more intense.

1-month SPEI for current month
1-month SPEI for current month.
1-month SPI for current month
1-month SPI for current month.

Temperatures during June 2019 were near to below normal across a large part of the CONUS. This reduced evapotranspiration, which made the SPEI comparable to the SPI. With temperatures near to below normal across much of the CONUS for the last several months, the SPEI and SPI maps generally had similar patterns (SPEI maps for last 3 and 6 months) (SPI maps for last 3 and 6 months).

60-month SPEI for current month
60-month SPEI for current month.
60-month SPI for current month
60-month SPI for current month.

Much of the West, especially from California to the central Rockies, experienced drier- and warmer-than-normal conditions for much of the last six years. The persistent and excessive heat increased evapotranspiration and made the drought conditions worse, as seen in a more extreme SPEI compared to SPI during this period (SPEI maps for last 24, 36, 48, 60, 72 months) (SPI maps for last 24, 36, 48, 60, 72 months).



Regional Discussion


Hawaii percent of normal precipitation map, March-June 2019
Hawaii percent of normal precipitation map, March-June 2019.

Hawaii:

June was wetter than normal across much of the Hawaiian Islands, with just a few stations drier than normal. But a dry March, April, and May spread dryness across the Hawaiian Islands for the last 4 to 6 months, with the dry conditions especially obvious for March-June. A mixed precipitation pattern was evident at the 9-month time scale, with wetter-than-normal conditions dominating at the longer time scales (precipitation anomaly maps for the last 1, 2, 3, 4, 6, 9, 12, 24, 36, 48, 60 months). Streamflow was below normal in some areas, especially on Maui and the Big Island. Extreme drought expanded slightly in the southern portion of the Big Island, but abnormally dry to severe drought conditions contracted across other parts of the state, with the drought area shrinking to about 43.3 percent of Hawaii on the July 2nd USDM map; abnormal dryness to extreme drought contracted from 92.4 percent last month to about 67.2 percent this month.



Alaska climate division precipitation rank map, July 2018-June 2019
Alaska climate division precipitation rank map, July 2018-June 2019.

Alaska:

June was drier than normal across much of Alaska except the panhandle, north slopes, and Aleutians. The precipitation anomaly pattern was mixed for the last 2 to 3 months, but dryness in the southeast — especially the panhandle — became evident at the 4-month and longer time scales (low elevation station precipitation maps for the last 1, 2, 3, 4, 6, 9, 12, 24, 36, 48, 60 months) (high elevation SNOTEL station precipitation maps for last 1 and 9 months, and SNOTEL basin map for last 9 months) (gridded precipitation percentile maps for the last 1, 3, 6 months) (climate division precipitation maps for the last 1, 3, 6, 12 months) (Leaky Bucket model precipitation percentile map). Temperatures during June were warmer than normal, with progressively warmer-than-normal temperatures across the state, and some record-warm temperatures, at longer time scales (low elevation station temperature maps for the last 1, 2, 3, 4, 6, 9, 12 months) (gridded temperature percentile maps for the last 1, 3, 6 months) (climate division temperature maps for the last 1, 3, 6, 12 months) (Leaky Bucket model temperature percentile map). Several large wildfires began across the state at mid-month, and quickly grew and multiplied by the end of the month (wildfire maps for June 20, 26, 30). Abnormally dry to extreme drought conditions continued in the panhandle, with abnormal dryness spreading into the eastern interior areas. About 12.4 percent of the state was in abnormally dry to extreme drought conditions on the July 2nd USDM map, roughly double the value at the end of May.



Puerto Rico percent of normal precipitation map, June 2019
Puerto Rico percent of normal precipitation map, June 2019.

Puerto Rico and U.S. Virgin Islands:

June 2019 was drier than normal across most of Puerto Rico and the U.S. Virgin Islands, with wetter-than-normal conditions occurring in northwest Puerto Rico and on the island of St. John. The pattern of dryness, from southwest Puerto Rico to the central areas and north central coast, is fairly consistent for the last 1 to 12 months. The U.S. Virgin Islands are mostly drier than normal for the last 2 to 12 months. Wet conditions dominate Puerto Rico at longer time scales (radar-based precipitation anomaly estimates for the last 1, 2, 3, 6, 9, 12 months) (low elevation station precipitation maps for the last 1, 2, 3, 4, 6, 9, 12, 24, 36, 48, 60 months) (climate engine model percent of normal precipitation map). Soils continued dry across much of Puerto Rico in the south and central to east, and some streams in the southwest and northeast areas had below-normal flow. As seen on the July 2nd USDM map, abnormal dryness and moderate drought expanded, and severe drought developed, with the drought area doubling to about 31.8 percent of Puerto Rico. In the U.S. Virgin Islands, moderate drought developed on St. Crois and St. Thomas, and St. John was abnormally dry, by the end of June.



CONUS State Precipitation Ranks:

Map showing June 2019 state precipitation ranks Map showing January-June 2019 state precipitation ranks

Washington state precipitation, January-June, 1895-2019

June 2019 was drier than normal across much of the West to northern Plains and Upper Midwest, and wetter than normal from the southern Plains to Northeast. Eight states had a rank in the driest third of the 125-year historical record for June. Wet conditions dominated the country for April-June, with only North Dakota ranking in the driest third of the historical record. The wet circulation pattern persisted across much of the CONUS for the last 12 months. Only the corners had significant drier-than-normal conditions. For January-June, South Carolina and North Dakota ranked in the driest third of the historical record, with Washington state having the eighth driest January-June. Only Washington and Montana were in the driest third of the 1895-2019 record for July-June, while at the other end of the spectrum, 18 states (all east of the Rockies) were record wet.


Agricultural Belts


Primary Corn and Soybean Belt precipitation, June, 1895-2019
Primary Corn and Soybean Belt precipitation, June, 1895-2019.
Primary Corn and Soybean Belt precipitation, March-June, 1895-2019
Primary Corn and Soybean Belt precipitation, March-June, 1895-2019.

June 2019 was mostly cooler than normal across the Primary Corn and Soybean agricultural belt, while precipitation was generally wetter than normal in the east and south and drier than normal in the northwest. The month ranked as the 26 th wettest and 49th coldest June, regionwide, in the 1895-2019 record.

March marks the beginning of the growing season for the Primary Corn and Soybean agricultural belt. March-June 2019 was mostly colder and wetter than normal. The 4-month period ranked as the third wettest and 43rd coldest March-June, regionwide, in the 1895-2019 record.


With the reduction of drought in the Southeast this month, drought decreased in the major agricultural regions of the CONUS. As of July 2nd, drought was affecting zero percent of the nation's corn production; one percent of soybean production, hay acreage, and cattle inventory; two percent of winter wheat production; and five percent of spring wheat production. According to June 30th U.S. Department of Agriculture (USDA) reports, 12 percent of the nation's corn crop, 11 percent of soybeans, 18 percent of cotton, ten percent of winter wheat, four percent of spring wheat, and seven percent of pasture and range were in poor to very poor condition, while 12 percent of the nation's topsoil and 11 percent of subsoil were short to very short of moisture (dry to very dry). But these national conditions reflect an average of very wet and very dry areas. The states having the driest soils were in the Northwest, Southwest and Southeast and included (percent area with short to very short topsoil / subsoil): California (80% / 65%), Oregon (50% / 41%), Washington (42% / 34%), Nevada (35% / 30%), New Mexico (67% / 68%), Alabama (49% / 46%), Georgia (41% / 33%), North Carolina (41% / 33%), and Virginia (32% / 18%). About 20 percent or more of the pasture and rangeland was in poor to very poor condition in California (35%), New Mexico (40%), Nevada (20%), and Ohio (21%).


NOAA Regional Climate Centers:


A more detailed drought discussion, provided by the NOAA Regional Climate Centers and others, can be found below.


As summarized by the High Plains Regional Climate Center, temperatures and precipitation varied throughout the region during June but did not deviate very far from normal. Agriculture continued to be negatively impacted by spring and early summer conditions. But these impacts were mostly due to unusual wetness, not drought. The percent of corn and soybeans that emerged had nearly caught up to the 5-year average throughout the region by the end of June. However, only about half of the corn and soybean crop in South Dakota and Kansas was in good to excellent condition, according to the July 2nd USDA Weekly Weather and Crop Bulletin. Wet conditions have contributed to increased disease issues, the prevalence of weeds due to the delayed application of spring weed control, and the likely need for additional drying. Late-planted crops will be at risk for a damaging freeze in the fall if they have not yet reached maturity.

Despite much of the region remaining free of drought and dryness during June, drought developed and intensified in North Dakota. According to the USDM, the area in the High Plains experiencing drought or abnormal dryness (D0-D4) increased from four percent to six percent over the course of the month. While no areas were experiencing drought (D1-D4) at the end of May, about two percent of the region was in drought by the end of June, which was down from three percent around the middle of the month. Northern North Dakota had a dry spring, receiving less than 50 percent of normal precipitation from March-May, causing impacts to agriculture. As a result, moderate drought (D1) spread across this area, and severe drought (D2) was introduced as well. Only recently did this area receive some relief, as the latter half of June brought beneficial precipitation to the area, improving drought conditions. Impacts that have been reported included curling corn leaves, distressed wheat and pastureland, replanting issues due to deficits in subsoil moisture, culling herds, and low water supplies. It is worth noting that this is the third consecutive summer that this region has experienced drought, which has taken a toll on agriculture in the area. As for improvements, several pockets of D0 were removed from Wyoming due to a favorably wet pattern in May and June. The only pocket of D0 that remained was along the western border. Elsewhere, abundant moisture kept the rest of the High Plains region free of drought and dryness.

As explained by the Southern Regional Climate Center, precipitation values for the month of June were above normal across a broad portion of the Southern region. Monthly temperatures exhibited a weak north-to-south pattern across the region, with above-normal temperatures in the south and below-normal temperatures in the north. At the end of June, drought conditions both improved and deteriorated across the Southern region. Severe drought classifications developed in far southern Texas, while moderate drought classifications expanded in far southern Texas. There were no drought conditions in Oklahoma, Tennessee, Louisiana, Mississippi, and Arkansas. There was a decrease in the overall area experiencing abnormally dry conditions, as areas in central Tennessee, coastal Mississippi, and western and southern Texas saw improvement or removal. However, abnormally dry conditions developed or expanded across parts of western and southeastern Tennessee, northeastern Mississippi, and southeastern Louisiana.

As described by the Midwest Regional Climate Center, June temperatures averaged near to slightly below normal in the Midwest. June precipitation for the Midwest ranged from less than half of normal in parts of Upper Michigan to more than twice normal in parts of southern Indiana, central Kentucky, and northeastern Ohio. Rain in Kentucky in June was enough to offset developing dryness coming into the month. Drier-than-normal conditions in Iowa, southern Minnesota, and Wisconsin eased the excessive wetness from earlier in the year. Northern Minnesota had been drier and the lack of moisture there expanded the dry areas.

The Midwest remained completely free of drought through June. This marked the six-month point of the streak (27 straight weeks as of July 2, 2019) which began at the beginning of 2019. The streak is easily the longest such streak for the Midwest since the inception of the USDM in 2000. There was some dryness in Kentucky and northern Minnesota as June began but generous rains in Kentucky led to the removal of all abnormally dry regions in the state during the month. Areas of abnormally dry conditions in northern Minnesota expanded in June.

As noted by the Southeast Regional Climate Center, temperatures were near average across the Southeast and Puerto Rico for the month of June, except the Florida peninsula, which was above average. Precipitation was highly variable across the Southeast region during June, which is common during the summer. The driest locations were found across southern and eastern North Carolina, northern South Carolina, northern and southern areas of Alabama, southern Florida, and north-central Puerto Rico. Monthly precipitation totals were 70 to less than 25 percent of normal in these areas. Guayama, PR (1911-2019) only reported 0.89 inch (23 mm) of precipitation for the month of June, which was 4.29 inches (109 mm) below normal making it the 3rd driest June on record. In contrast, the wettest locations were found across eastern Virginia, western North Carolina, southern South Carolina, and central Georgia.

Drought conditions decreased across the region for the month of June. At the beginning of the month, severe drought (D2) covered 2.8 percent of the region, including a small area of southern South Carolina and southern Georgia. By the end of the month, D2 conditions were limited to 0.5 percent of the region. There was a significant decrease in moderate drought (D1) and abnormally dry (D0) conditions during the month, with decreases from 29.8 percent to 6.4 percent of the region and 54.7 percent to 29.2 percent to 15.5 % of the region, respectively. Puerto Rico saw an increase in moderate drought conditions from 15.5 percent of the region at the beginning of the month to 32.2 percent of the region by the end of the month. Heavy rainfall at the beginning of the month contributed to the flooding of fields and increased weed and disease pressure on crops, especially across parts of the western Carolinas and northern Georgia. Farther to the south and east, dryness and heat at the end of the month led to stressed crop fields, livestock pastures, and hayfields in portions of Alabama and the southern coast of North Carolina. Georgia's watermelon season has begun, and growers report that after two years of unpredictable and extreme weather patterns, this growing season is off to a productive start.

As explained by the Northeast Regional Climate Center, the Northeast had its 16th wettest June since 1895 with 4.94 inches (125.48 mm) of precipitation, which was 117 percent of normal. The region's June average temperature of 64.5 degrees F (18.1 degrees C) was 0.7 degrees F (0.4 degrees C) colder than normal. There was no drought or abnormal dryness on the USDM in the Northeast this month.

As summarized by the Western Regional Climate Center, precipitation was below normal across much of the West; however, June is typically one of the driest months of the year for some parts of the region. Temperatures were above normal in coastal states and near to slightly below normal elsewhere in the region. Much of the Pacific Northwest and Intermountain West observed drier-than-normal conditions this month. On the USDM, some areas of improvement were seen along the northern border of New Mexico and Arizona. Western Oregon, western Washington, and several areas along the northern border of the western states saw expansion of drought conditions this month. At the end of the month, roughly 55% of Washington was designated as in moderate to severe drought, as compared to 44% at the beginning of the month. In June, roughly 80% of USGS gauged streams in Washington were running below normal. Outlooks favor warmer-than-normal conditions for the summer season, which may exacerbate drought conditions.

Much of Alaska experienced warmer- and drier-than-normal conditions during June. Anchorage reported its all-time warmest and driest June in a 68-year record. Temperatures averaged to 60.5 F (15.8 C), 5.2 F (2.9 C) above normal. Precipitation totaled 0.06 in (2 mm), 6% of normal. In the northwestern part of the state, Kotzebue reported an average temperature of 56.8 F (13.8 C), 11.1 F (6.2 C) above normal and set the record for warmest June by 3.4 F (1.9 C). Records for Kotzebue began in 1897. Although a few southeastern Alaska stations reported above normal precipitation this month (e.g., Ketchikan reported 7.97 in/202 mm, 120% of normal), moderate to extreme drought conditions persist in this region. Roughly 3% of the state is experiencing drought conditions, all in the Panhandle. Ketchikan anticipates needing backup generators through at least October as reservoirs remain too low to generate hydropower. In Alaska, 38 large wildfires have burned over 418,000 acres (169,000 hectares) this year. While the number of acres burned is above normal, it is not yet approaching a record. Wildfires across Alaska have created air quality impacts in the Fairbanks and Anchorage areas and have threatened some neighborhoods, prompting evacuations. Well above normal temperatures and dry weather have created conditions favorable for large wildfires.

Above-normal temperatures dominated in Hawaii, driven primarily by above-normal sea surface temperatures in the Central Pacific. Many areas of the state observed above-normal precipitation. In contrast, the windward side of the Big Island reported well below-normal precipitation. Drought improvement occurred on the windward sides of the islands in Hawaii and Maui Counties, with more island-wide improvement for Oahu and Kauai. Moderate to extreme drought conditions remain to some degree on the leeward sides of all islands.


U.S.-Affiliated Pacific Islands


The NOAA National Weather Service (NWS) offices, the Pacific ENSO Applications Climate Center (PEAC), and partners provided reports on conditions across the Pacific Islands.

In the U.S. Affiliated Pacific Islands (USAPI) (maps — Federated States of Micronesia [FSM], Northern Mariana Islands, Marshall Islands [RMI], Republic of Palau, American Samoa, basinwide), June 2019 was drier than normal in the northern portions of Micronesia and wetter than normal in the southern portions near the equator. Drier-than-normal stations included Koror, Guam, Saipan, and Kwajalein, and wetter-than-normal stations included Yap, Chuuk, Lukonor, Pohnpei, Kapingamarangi, Kosrae, Majuro, and Pago Pago.

Inter-Tropical Convergence Zone (ITCZ) precipitation kept rainfall amounts above the monthly minimum needed to meet most water needs (8 inches) in Palau and southern parts of the FSM and RMI, but El Niño- and post-El Niño-like conditions kept northern portions dry. Monthly rainfall totals exceeded 8 inches at Koror (Palau); Yap, Woleai, Chuuk, Lukonor, Nukuoro, Kapingamarangi, Pohnpei, Mwoakilloa, Pingelap, Kosrae (FSM); Ailinglapalap, Majuro, and Mili (RMI). But the North Pacific subtropical ridge (North Pacific High) sent dry trade-winds across the northern regions, resulting in a dry month in terms of drought at the rest of the stations in Micronesia — Guam, Rota, Saipan (Marianas); Fananu (FSM); Jaluit, Kwajalein, Utirik, and Wotje (RMI). At these stations the June rainfall amounts were below the minimum thresholds (4 or 8 inches) required to meet most monthly water needs. It was a dry month (below the minimum threshold of 8 inches) at Pago Pago in American Samoa, where South Pacific Convergence Zone rainfall stayed mostly just to the north and west of the islands. The 4- and 8-inch thresholds are important because, if monthly precipitation falls below the threshold, then water shortages or drought become a concern.


X
  • Percent of Normal Precip
  • Precipitation
  • Normals
Pacific Island Percent of 1981-2010 Normal Median Precipitation
Station Name Jul
2018
Aug
2018
Sep
2018
Oct
2018
Nov
2018
Dec
2018
Jan
2019
Feb
2019
Mar
2019
Apr
2019
May
2019
Jun
2019
Jul-
Jun
Chuuk107%96%158%93%142%76%183%122%175%48%42%125%106%
Guam NAS146%149%183%78%61%152%106%228%39%45%77%46%101%
Kapingamarangi142%67%128%158%223%93%195%44%197%127%169%172%128%
Koror87%N/A63%119%140%111%96%40%84%94%57%93%N/A
Kosrae106%159%65%34%58%49%93%98%143%137%152%103%86%
Kwajalein90%193%81%63%107%99%49%183%52%22%159%69%95%
Lukonor123%83%96%89%78%70%148%71%103%126%32%127%84%
Majuro142%102%94%67%69%112%93%74%102%35%160%103%95%
Pago Pago192%181%132%128%117%176%83%200%107%108%154%117%122%
Pohnpei130%166%93%100%74%100%134%79%143%66%45%159%102%
Saipan88%146%172%90%83%137%70%59%28%35%243%58%109%
Yap105%100%109%46%136%125%249%30%107%52%91%109%99%
Pacific Island Precipitation (Inches)
Station Name Jul
2018
Aug
2018
Sep
2018
Oct
2018
Nov
2018
Dec
2018
Jan
2019
Feb
2019
Mar
2019
Apr
2019
May
2019
Jun
2019
Jul-
Jun
Chuuk12.7712.3318.5510.6615.028.5318.498.8714.566.004.7414.62145.14
Guam NAS14.8421.8923.178.874.517.754.246.900.811.152.612.8599.59
Kapingamarangi20.155.4712.6712.9820.719.1317.874.0622.5617.3320.4623.68187.07
Koror16.19N/A7.3714.1215.9212.379.793.456.246.896.7816.30N/A
Kosrae15.8322.609.193.708.097.9215.5812.6223.0223.9626.9115.08184.5
Kwajalein8.8818.818.657.0512.126.581.544.821.221.1410.714.7686.28
Lukonor19.6611.709.7910.067.127.8912.416.339.5814.303.7514.80127.39
Majuro15.8811.9610.468.539.2912.717.235.096.743.3416.1411.31118.68
Pago Pago10.689.768.6011.8311.9022.5911.1024.0411.4710.1714.916.24153.29
Pohnpei20.1123.6111.7015.3110.9716.1317.687.5718.8412.238.9423.56186.65
Saipan7.8819.1217.399.594.645.281.761.540.530.935.782.1176.55
Yap15.8114.8214.655.5612.0310.6815.901.574.882.927.1513.14119.11
Pacific Island 1981-2010 Normal Median Precipitation (Inches)
Station Name Jul
2018
Aug
2018
Sep
2018
Oct
2018
Nov
2018
Dec
2018
Jan
2019
Feb
2019
Mar
2019
Apr
2019
May
2019
Jun
2019
Jul-
Jun
Chuuk11.9812.8611.7111.5110.6111.2510.107.258.3212.4711.3011.66136.77
Guam NAS10.1414.7412.6611.447.385.114.013.032.072.533.406.1899.09
Kapingamarangi14.158.139.938.199.279.849.159.2711.4313.6412.0813.78145.85
Koror18.5313.5011.7711.8411.3911.1610.188.567.447.3211.8317.48152.90
Kosrae14.9114.2214.2210.9413.8316.1116.6712.9316.0617.5117.7514.64213.87
Kwajalein9.879.7410.7411.1811.286.663.162.642.355.266.726.9390.41
Lukonor15.9314.0410.1511.329.0811.278.418.939.2611.3111.6911.65151.36
Majuro11.1711.6911.1712.7313.4411.397.746.886.589.4210.1111.01125.25
Pago Pago5.555.386.539.2610.1412.8413.3412.0010.689.399.665.33125.57
Pohnpei15.4314.2612.5515.2714.8316.0813.189.5513.1718.4119.9614.81182.36
Saipan8.9113.1310.0910.625.613.852.532.591.892.632.383.6270.25
Yap15.0814.8213.5012.188.838.516.395.194.565.637.8512.04120.31

As measured by percent of normal precipitation, Kwajalein was drier than normal in the short term (June and the last 3 months [April-June 2019]) and long term (year to date [January-June] and last 12 months [July 2018-June 2019]). Saipan, Guam, and Koror were drier than normal for June, April-June, and January-June, but near to wetter than normal for July-June (the 12-month time period was missing for Koror). Lukonor was wetter than normal for June but drier than normal for the other three time scales. Pohnpei and Yap were drier than normal at the 3- and 6-month time scales, but near to wetter than normal at the 1- and 12-month time scales. Majuro was near to wetter than normal in the short-term, but drier than normal in the long-term. Chuck was drier than normal at the 3-month time scale, and Kosrae was drier than normal at the 12-month time scale, but both were near to wetter than normal for the other three time scales. Kapingamarangi and Pago Pago were wetter than normal for all four time periods. It should be noted that the monthly normal precipitation amount can vary significantly from month to month due to the strong seasonality of equatorial Pacific precipitation.

Percent of normal precipitation for current month for the Marianas Islands
Percent of normal precipitation for current month for the Marianas Islands.
Percent of normal precipitation for current month for the Marshall Islands
Percent of normal precipitation for current month for the Marshall Islands.

In the Marianas Islands, precipitation mostly has been drier than normal regionwide for the last one to nine months. A mixed precipitation anomaly pattern exists at longer time scales (percent of normal precipitation maps for the last 1, 2, 3, 4, 6, 9, 12, 24, 36, 48, 60 months). In the Marshall Islands, the spatial pattern of precipitation consists generally of drier-than-normal conditions in the north and west and near- to wetter-than-normal conditions in the southeast (percent of normal precipitation maps for the last 1, 2, 3, 4, 6, 9, 12, 24, 36 months).



The USAPI U.S. Drought Monitor drought map valid for the end of June 2019
The USAPI U.S. Drought Monitor drought map valid for the end of June 2019.

According to the end-of-June USDM produced for the USAPI, exceptional drought (D4) continued at Utirik and Wotje in the northern RMI; extreme drought (D3) continued at Guam, Rota, and Saipan in the Marianas; moderate drought (D1) continued at Kwajalein and developed at Jaluit; Fananu improved to moderate drought; abnormally dry (D0) conditions continued at Majuro and developed at Ailinglapalap; Palau and Yap improved to abnormally dry; and drought or abnormally dry conditions ended at Woleai, Chuuk, Lukonor, and Nukuoro. Storage in the Majuro reservoirs improved during the last half of the month, and ended June at about 29.9 million gallons, or about 83 percent of maximum, which is above the 80 percent threshold for concern. Water restrictions at Majuro have been greatly reduced, but some continue due to the large population and variable rainfall, and this is reflected by the D0 status. According to reports relayed by the Guam NWS office (June 13, June 27), health issues related to water problems have been reported at Ebeye in the Marshall Islands, discarded cigarettes caused some fires on Majuro, and draw-down of fresh water resources continues to be a concern in the Marianas; wildfires are a continuing risk in the Marshalls and Marianas.

The dryness in parts of the RMI and the Marianas was significant. Only 1.51 inches of rain fell at Rota in June, 2.11 inches at Saipan, and 2.85 inches at Guam. These are about half of the June normal for Guam and Saipan, and rank June 2019 as the seventh driest June out of 63 years of data for Guam and 39 years of data for Saipan. Kwajalein's 4.76 inches of rain gave June 2019 a rank of eighth driest out of 68 years, and Jaluit had the fifth driest June out of 35 years. June 2019 was wetter than normal at some stations, but dry conditions across most of Micronesia began late last year. Even with the wet June at some stations, the cumulative effect of the prolonged dryness resulted in the fourth driest October-June for Saipan, sixth driest May-June for Lukonor, fifth driest July-June for Woleai, sixth driest April-June for Chuuk, fourth driest March-June for Guam, sixth driest July-June for Ailinglapalap, second driest July-June for Jaluit, driest March-June for Utirik, sixth driest September-June for Wotje, and eighth driest September-June for Kwajalein.

The following analysis of historical data for the USAPI stations in the Global Historical Climatology Network-Daily (GHCN-D) dataset, augmented with fill-in data from the 1981-2010 Normals, helps put the current data into historical perspective by computing ranks based on the period of record. The table below lists the precipitation ranks for June 2019, January-June 2019 (the year to date), and July 2018-June 2019 (the last 12 months). Some stations have a long period of record and their dataset is fairly complete, while other stations have a shorter period of record and the dataset has some missing data.

Rank, Number of Years with data, and Period of Record for USAPI stations for June 2019, January-June 2019, and July 2018-June 2019.
Rank of 1 = driest.
Station Jun 2019
Rank
Jun
No. of Years
Jan- Jun 2019
Rank
Jan- Jun
No. of Years
Jul 2018- Jun 2019
Rank
Jul- Jun
No. of Years
Period of Record
Pago Pago 32 54 45 53 49 53 1966-2019
Saipan 7 39 8 38 23 30 1981-2019
Kapingamarangi 28 29 23 23 16 16 1962-2019
Kosrae 26 52 26 41 11 33 1954-2019
Lukonor 28 35 12 35 8 22 1981-2019
Nukuoro 33 37 13 36 12 34 1981-2019
Pingelap 22 37 MSG 34 MSG 32 1981-2019
Woleai 35 37 8 29 5 22 1968-2019
Yap 45 68 30 68 26 68 1951-2019
Pohnpei 64 68 29 68 33 68 1951-2019
Chuuk 51 68 40 68 35 68 1951-2019
Guam 7 63 10 62 32 62 1957-2019
Koror 36 68 12 68 MSG 67 1951-2019
Ailinglapalap 19 36 13 36 6 33 1981-2019
Jaluit 5 35 4 35 2 33 1981-2019
Mili 31 35 21 35 MSG 31 1981-2019
Utirik 11 15 2 9 1 5 1985-2019
Wotje 12 35 7 35 MSG 31 1981-2019
Kwajalein 8 68 15 67 13 67 1952-2019
Majuro 33 66 26 65 16 65 1954-2019

Precipitation amount for current month for U.S. Affiliated Pacific Island stations

Percent of normal precipitation for current month for U.S. Affiliated Pacific Island stations

Percent of normal precipitation for last 3 months for U.S. Affiliated Pacific Island stations

Percent of normal precipitation for the year to date for U.S. Affiliated Pacific Island stations

Percent of normal precipitation for last 12 months for U.S. Affiliated Pacific Island stations

SPI values for seven time periods for Pacific Islands, computed by the Honolulu NWS office.
SPI values for seven time periods for Pacific Islands

[top]


State/Regional/National Moisture Status
A detailed review of drought and moisture conditions is available for all contiguous U.S. states, the nine standard regions, and the nation (contiguous U.S.):

States
alabama arizona arkansas california colorado connecticut
delaware florida georgia idaho illinois indiana
iowa kansas kentucky louisiana maine maryland
massachusetts michigan minnesota mississippi missouri montana
nebraska nevada new hampshire new jersey new mexico new york
north carolina north dakota ohio oklahoma oregon pennsylvania
rhode island south carolina south dakota tennessee texas utah
vermont virginia washington west virginia wisconsin wyoming

Regional
northeast u. s. east north central u. s. central u. s.
southeast u. s. west north central u. s. south u. s.
southwest u. s. northwest u. s. west u. s.

National
Contiguous United States

[top]


Contacts & Questions
For additional, or more localized, drought information, please visit:

Citing This Report

NOAA National Centers for Environmental Information, State of the Climate: Drought for June 2019, published online July 2019, retrieved on September 22, 2019 from https://www.ncdc.noaa.gov/sotc/drought/201906.

Metadata