Drought - May 2013


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Issued 13 June 2013
Contents Of This Report:
Map showing Palmer Z Index

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

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Detailed Drought Discussion

Overview

Weather systems moving in an weather patternjet stream flow propagated several upper-level troughs and ridges across the country during May. Cold fronts and warm fronts moving with these upper-level systems brought migrating spells of cooler-than-normal and warmer-than-normal weather to parts of the country. Some of the systems tapped Gulf of Mexico moisture, resulting in heavy rains from the parts of the Plains to the Midwest and causing extensive flooding, especially in the Midwest. The rain-producing systems largely missed the West and Ohio Valley where dry weather prevailed, and parts of the Mid-Atlantic coast and Gulf of Mexico coast were also drier than normal this month. Drought expanded in the West, where persistent dryness gave California the driest year to date and New Mexico the driest June-May, but drought contracted under beneficial rains in the Plains, Midwest, and Southeast. When the temperature and precipitation are averaged across the country for the entire month, May 2013 ranked as the 40th warmest and 17th wettest May in the 119-year record. The May precipitation helped reduce the moderate-to-exceptional national drought footprint from 46.9 percent at the end of April to 44.1 percent at the end of May. According to the Palmer Drought Index, which goes back to the beginning of the 20th century, 38.0 percent of the contiguous U.S. was in moderate to extreme drought at the end of May, a decrease of about 4 percent compared to last month.

The U.S. Drought Monitor drought map valid June 4, 2013
The U.S. Drought Monitor drought map valid June 4, 2013.

By the end of the month, the core drought areas in the U.S. included:

  • a large area of moderate (D1) to severe (D2) drought stretching from the West, across the Northern and Southern Plains, and into the Upper Midwest, with spots of extreme (D3) drought in the West, and an area of intense extreme to exceptional (D4) drought lingering from the Southwest to the Southern and Central Plains states;
  • Hawaii, where moderate to extreme (D3) drought largely persisted; and
  • spots of moderate drought in the Southeast, Northeast, and Alaska.

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.

Palmer Z Index map Palmer Hydrological Drought Index map

Used together, the Palmer Z Index and PHDI maps show that May short-term dry conditions occurred over long-term dry conditions that existed at the end of April across parts of the West and Southern to Central Plains, exacerbating the drought, and short-term dry conditions occurred over parts of the Ohio Valley to southern Great Lakes, which were neutral to wet at the end of April. Short-term wet conditions happened over long-term dry conditions across much of the Northern and Central Plains to Midwest, further improving drought 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

The 1-month SPI map shows dryness in two distinct dry areas — the Southwest to Southern High Plains and Ohio Valley to southern Great Lakes — as well as spotty areas in the West, Southeast, and Mid-Atlantic coast. It also shows unusual moisture from the Midwest to Northern High Plains and spotty areas in the Pacific Northwest, Southeast, and Northeast. The dryness in the Southwest to Southern Plains is most intense at 2 to 3 months and 12 to 24 months. Much of the West is dry at 2 to 24 months. The eastern portions of the Central to Northern Plains are wet at 1 to 6 months, with the 9-month SPI showing a transition period to dry conditions at 12 to 24 months. The recent wetness in the Midwest is reflected on the 1-month to 9-month SPI maps, and is enough to counter the dryness of last year even on the 12- to 24-month maps. The May wetness in the Northeast is enough to counter earlier dryness, although the 3-month map still shows an area of dryness from New England to the Appalachians. Enough precipitation has fallen in the Southeast to make the region largely wet on the 1- to 12-month maps, with widespread dryness still evident only on the 24-month map.


6-month Standardized Precipitation Index 12-month Standardized Precipitation Index 24-month Standardized Precipitation Index


Agricultural, Hydrological, and Meteorological Indices and Impacts

USDA statewide topsoil moisture percentages short or very short
USDA statewide topsoil moisture percentages short or very short
USGS monthly streamflow percentiles
USGS monthly streamflow percentiles

Drought conditions were reflected in numerous agricultural, hydrological, and other meteorological indicators, both observed and modeled.

Agricultural:

According to the U.S. Department of Agriculture (USDA), as of June 4, 47 percent of winter wheat, 46 percent of cattle, 33 percent of hay, 21 percent of corn, and 12 percent of soybeans were in drought. These percentages are less than the corresponding percentages from a month ago. June 2 USDA statistics revealed that 43 percent of the U.S. winter wheat crop was rated in poor to very poor condition, with statewide percentages as high as 79 percent in Texas, 60 percent in Colorado, 58 percent in South Dakota, 54 percent in Oklahoma, and 53 percent in Nebraska. The values were below 50 percent, but still high, in Kansas (45%) and Oregon (32%). June 2 statistics also reveal 25 percent of the nation's pasture and rangeland rated in poor to very poor condition, a drop of 11 percent compared to last month, with statewide values as high as 92 percent in New Mexico, 75 percent in Arizona, 65 percent in California, 58 percent in Nebraska, 57 percent in Nevada, and 54 percent in Colorado. The statewide percentages were above average from Texas to Wyoming from Nebraska to Oregon, and from Oklahoma to California

Map showing NOAA/NWS/CPC modeled monthly soil moisture percentiles
Map showing NOAA/NWS/CPC modeled monthly soil moisture percentiles.

Hydrological:

Map showing USDA NRCS mountain snowpack water equivalent percent of normal
Map showing USDA NRCS mountain snowpack water equivalent percent of normal.

Meteorological:

Map showing year-to-date percent of normal precipitation
Map showing year-to-date percent of normal precipitation.


Regional Discussion

Hawaii: Beneficial rain fell across the Hawaiian Islands during May 2013, improving drought conditions. The May rainfall was still evident on the precipitation anomaly map for the last two months, but abnormally dry conditions were evident at three months and more widespread at longer time scales (last 5, 6, 8, 12, 24, and 36 months). The percent of the state experiencing moderate to extreme drought area fell from 40 percent last month to 33 percent this month.

Alaska: May 2013 was drier than normal from southwestern to central Alaska and wetter than normal in the southeast and along the northwest coast. This pattern generally persisted at the 2- and 3-month time scales and became mixed at longer time scales (5, 6, 8, 12, 24, and 36 months). Abnormal dryness covered about a fifth of the state on the USDM map with a spot of moderate drought continuing in the Koyukuk Basin where water-year-to-date (October-present) precipitation was low.

Puerto Rico: Above-normal precipitation fell over western and northern parts of Puerto Rico during May, with the south central coast drier than normal. The drier-than-normal area extended from the south central coast into the interior at 2 to 3 months, with some dryness also along the east coast. The dry area expanded in size at longer time scales (last 5, 6, and 8 months), but streamflow averaged normal and there was no drought or abnormal dryness on the USDM map.

CONUS State Ranks:

Current month state precipitation ranks Current three-month state precipitation ranks

On a statewide basis, May 2013 was dominated by wet conditions in the northern tier states, but six states (Idaho, Ohio, Delaware, Arizona, New Mexico, and Texas) ranked in their driest third of the historical record. Dryness for the last three months was centered in the West, Southern Plains, and Ohio Valley to Northeast, where 18 states ranked in the driest third of the historical record — two of which (New Mexico [second driest] and California [eighth driest]) had a top ten driest spring (March-May) 2013.

current year-to-date state precipitation ranks California statewide precipitation, January-May, 1895-2013

The year to date (January-May 2013) state precipitation rank pattern was similar to that for spring — 20 states in the West, Southern Plains, and Ohio Valley to New England ranked in the driest third of the historical record. Four of them (California, Nevada, Oregon, and Idaho) were in the top ten driest category, with Connecticut and New Mexico not far behind at eleventh and twelfth driest, respectively. California had the driest January-May in the 119-year record.

6-month state precipitation ranks 12-month state precipitation ranks

December was a relatively wet month in the West and Northeast, so the six month (December 2012-May 2013) statewide precipitation ranks are not as dry there as with the year to date, but nine states still rank in the driest third of the historical record for December-May. California ranked in the top ten driest category at eighth driest. The last twelve months were the driest June-May on record for New Mexico and ranked in the top ten driest category for five others (Wyoming [third driest], Nebraska [fourth driest], Colorado [seventh driest], Kansas [eighth driest], and California [eighth driest]). An additional eight states in the West and Plains, plus Connecticut, ranked in the driest third of the historical record. New Mexico entered into a dry period beginning about October 2010 and marked the beginning of the recent expansion of drought for the nation. Similar temporal patterns can be seen in the USDM percent area time series for the Southern Plains and, to a lesser extent, the West and Central to Northern Plains. But New Mexico has been an epicenter of the recent surge in drought. The dryness has been so prolonged in the state that October 2010-May 2013 has been the driest such 33-month period in the 119-year record.

New Mexico statewide precipitation, June-May, 1895-2013 New Mexico prcent area in moderate to exceptional drought, 2000-2013

Western U.S.


Percent area of the Western U.S. in moderate to extreme drought, January 1900 to present, based on the Palmer Drought Index
Percent area of the Western U.S. in moderate to extreme drought, January 1900 to present, based on the Palmer Drought Index.

May 2013 was drier than normal for much of the West, especially the Southwest. The last five months have had record dry conditions, especially along the coastal states (as noted above). Water year-to-date (October-present) precipitation was below normal for much of the West, especially the southern portions. Only a few areas, primarily the northern basins, averaged near to above normal. This pattern is evident in both the high elevation (SNOTEL) station percentiles and basin averages, as well as in low elevation station observations and 6- and 9-month SPI. The end of May is past the peak snow season, so snow normals are rapidly decreasing this time of year. Snow pack water content (station and basin percent of normal) was below normal or already melted in most basins. The lack of source meltwater (from the mountain snowpack) was reflected in low streamflows for many western basins. Reservoir storage was near average in Montana and Wyoming, but below average in most other states. Integrated satellite and ground observations of vegetation condition (VegDRI) and modeled vegetation condition (Soil Water Index, Water Requirement Satisfaction Index) indicated widespread stress on vegetation across the West, especially the Southwest. According to the USDM, 72.9 percent of the West was experiencing moderate to exceptional drought at the end of May, an increase over last month. The Palmer Drought Index percent area statistic was 74.4 percent, an increase over last month.


Wheat, Corn, and Soybean Agricultural Belts


Primary Hard Red Winter Wheat Belt precipitation, October-May, 1895-2013
Primary Hard Red Winter Wheat Belt precipitation, October-May, 1895-2013.
Primary Corn and Soybean Belt precipitation, April-May, 1895-2013
Primary Corn and Soybean Belt precipitation, April-May, 1895-2013.

Like last month, eastern and northern parts of the Primary Hard Red Winter Wheat agricultural belt received above-normal precipitation during May 2013, but the western and southern areas continued dry. The region as a whole had the 46th driest May in the 1895-2013 record. For the period since October, this region had the 24th driest October-May in 2013. May 2013 ranked as the 51st warmest May, while October 2012-May 2013 had a median rank of 59th warmest regionwide.

The Primary Corn and Soybean agricultural belt was drier than normal in the eastern sections but very wet elsewhere this month. For the region as a whole, May 2013 ranked as the sixth wettest May in the 1895-2013 record. When April's precipitation is included, the last two months has been the wettest April-May on record. The wetness has been consistent for the growing season to date with March-May 2013 ranking as the third wettest March-May on record. For regional temperature, 2013 had the 55th warmest May and eighth coolest March-May in the 199-year record.

NOAA Regional Climate Centers:


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

SoutheastSouthMidwestNortheastHigh Plains
WestPacific Islands

As described by the High Plains Regional Climate Center, May 2013 was a month of extremes for the High Plains region with a wide variety of weather ranging from record-breaking rainfall, record-breaking snowfall, record-breaking heat, and severe storms with flash-flooding, extremely large hail, high winds, and tornadoes. Much of the temperature story is washed out by the monthly averages which do not capture the wide swings in temperature. Monthly averages indicated that the eastern portion of the region, along with central Colorado, had temperatures just below normal, while the western portion of the region had average monthly temperatures which were just above normal. In regards to precipitation, by the end of the month, it was generally a story of the "haves" and the "have nots", with most locations receiving either well above or well below normal precipitation and not too many in between. Those missing out on the heavy precipitation this month included the western half of Kansas, eastern and southern Colorado, southern and eastern Wyoming, and just a few pockets of South Dakota and Nebraska where precipitation totals were less than 70 percent of normal. Much of southeastern Colorado and southwestern Kansas received less than 25 percent of normal precipitation. This lack of precipitation hit eastern Colorado and western Kansas especially hard since portions of that area have been dealing with drought issues since 2011. Overall, the cool, wet conditions this spring resulted in a slow start to corn and soybean planting; however, once the conditions improved, producers were able to make significant progress to catch up. Unfortunately, winter wheat was still suffering as nearly half the crop remained in poor to very poor condition in Colorado, Kansas, Nebraska, and South Dakota.

There were significant changes to the USDM over the past month. At the end of May, approximately 73 percent of the region was in moderate (D1) to exceptional (D4) drought, down from 85 percent at the end of April. Ample, and in some cases excessive, precipitation helped reduce or eliminate drought in portions of each state. North Dakota is now virtually drought free, with only 0.01 percent of the state in the D1 designation. Significant improvements were also made to the extreme drought conditions (D3) in both South Dakota and Nebraska. Drought free areas have begun to emerge or grow in eastern South Dakota, southeastern Nebraska, and eastern Kansas. While much of the region had heavy rains, portions of eastern Colorado and western Kansas missed out and D4 conditions persisted there. Like last month, Kansas had the largest area of D4 coverage with 22 percent, up just a bit from the 20 percent at the end of April.

As explained by the Southern Regional Climate Center, unlike April, the month of May was generally a cooler than normal month for most of the Southern region. With the exception of the north western corner of the region, temperature averages for the month ranges from 0 to 4 degrees F (0 to 2.22 Degrees C) below normal. In the Texas and Oklahoma panhandles, temperature averages were only slightly higher than normal. May precipitation in the Southern region varied significantly, with a patchy spatial pattern including areas of extreme dryness and areas of intense saturation. Within the Southern region, anomalously high precipitation totals were observed in: south east Louisiana, north eastern Arkansas, north western Mississippi, south western Tennessee, and small pockets in central Texas. Conversely, areas of dryness included: north western Texas, western Oklahoma, northern Louisiana, and along much of the northern Gulf coast of Texas. Prolonged dryness in the north western area of Texas and in western Oklahoma over the past month has led to a significant increase in the amount of extreme and exception drought conditions. Elsewhere, drought conditions have improved as a result of some much needed rainfall. Areas of improvement include central and southern Texas, southeastern Arkansas, and central Oklahoma.

As summarized by the Midwest Regional Climate Center, May temperatures were generally above normal in eastern parts of the Midwest and below normal in western parts. Daily temperature records alternated between record highs and record lows as weather moved across the region during the month. The warmer temperatures in the east brought spring (March to May) temperatures close to normal while the cool temperatures in the west continued the cool spring pattern.

May precipitation also varied across the Midwest in May. Like temperature, precipitation varied from west to east with wet weather in the west and dry conditions in the east. A large area that included parts of Missouri, Illinois, Iowa, Minnesota, and Wisconsin had more than 7 inches (178 mm) of precipitation and totals exceeded 15 inches (381 mm) at some stations in central Iowa. Using data that extends back to 1895, Iowa set a new statewide precipitation record for both the month and the spring season. The cool spring weather had suppressed severe weather in the region through April but that all changed in May. An active weather pattern which brought sufficient warmth to support strong thunderstorms contributed to a big increase in severe weather reports in May. Spring planting was well behind the 5-year average at the beginning of May but some periods of favorable weather allowed farmers to get in the fields. Working quickly when they had their opportunities, allowed farmers planting corn to catch up nearly to average while soybean planting also made good progress in May. The May rains continued to erode away the remaining drought areas in the Midwest. By the end of the month, the area of the Midwest in drought dropped to less than 4 percent and severe drought area fell below 1 percent. The heavy rains in 2013 have restored much of the soil moisture, stream flow, and small lake level deficits from 2012. River levels on the Mississippi River went from near record low levels in January to major flooding in May. Major flooding affected numerous river systems in the western half of the region from Missouri to western Michigan and areas to the west.

As noted by the Southeast Regional Climate Center, mean temperatures in May were below average across much of the Southeast region. The greatest departures were found across parts of Alabama, Georgia, South Carolina, and northeastern Florida, where monthly temperatures were 2 to 3 degrees F (1.1 to 1.6 degrees C) below average. Temperatures across the rest of the region were 1 to 2 degrees F (0.5 to 1.1 degrees C) below average, except across eastern portions of Virginia and North Carolina, where monthly temperatures were as much as 2 degrees F (1.1 degrees C) above average. Monthly temperatures were also above average across Puerto Rico, while temperatures were generally below average across the U.S. Virgin Islands.

Monthly precipitation totals were above normal across a large portion of the Southeast in May. The wettest locations were found across southern and northeastern Florida, as well as northern sections of Alabama, Georgia, and South Carolina, western sections of North Carolina, and the northern shores of Puerto Rico, where monthly precipitation totals were as much as 300 percent of normal. San Juan, PR recorded its 3rd wettest May with 14.54 inches (369.3 mm) of rain (period of record: 1898-2013). In contrast, May was a relatively dry month across the western Panhandle of Florida, southern sections of Alabama and Georgia, and eastern North Carolina, where monthly precipitation totals were less than 50 percent of normal.

Only minor changes in the USDM were noted across the Southeast in May. Areas of moderate (D1) and severe (D2) drought were reduced slightly across north-central Florida, while abnormally dry conditions (D0) were eliminated across South Carolina, marking the first time the state has been drought-free since April 2010. Abnormally dry conditions continued to persist across eastern North Carolina, while areas of moderate drought re-emerged across extreme northwest Florida and southern Alabama. Although conditions in these areas continued to limit forage growth, the dry weather and soils aided in the planting and harvesting of many summer crops. Saturated soils combined with cool spring temperatures delayed the planting and harvesting of crops across much of North Carolina and Virginia. The most significant agricultural impacts were noted across western North Carolina, where heavy rains flooded fields and washed away crops. The cool, wet conditions in May were also associated with a complete absence of ground-level ozone violations in the Atlanta, GA metropolitan area.

As explained by the Northeast Regional Climate Center, with an average temperature of 57.7 degrees F (14.3 degrees C), the Northeast was 1.3 degrees F (0.7 degrees C) above normal for May. The region was slightly above normal for spring. After four dry months in a row, the Northeast was slightly wetter than normal in May. The region received 4.09 inches (103.89 mm) of precipitation, 102 percent of normal. The states were split with six wetter than normal and six drier. Despite a wet May in some states, all states ended spring drier than normal. Rhode Island was the driest state at 59 percent of normal, making it their 17th driest spring in 119 years. Connecticut, with 62 percent of normal precipitation, had their 20th driest spring on record. Departures for the rest of the states ranged from 74 percent of normal in Pennsylvania to 99 percent of normal in Vermont.

At the beginning of May, a continuing lack of precipitation caused most of New England to be under abnormally dry (D0) or moderate drought (D1) conditions according to the USDM. Rains during the second half of the month helped ease dryness, but areas of D0 and D1 remained. Though D1 conditions eased, abnormal dryness lingered in parts of New York. At the start of the month around two-thirds of Pennsylvania was abnormally dry, but improving conditions lowered that to one-fourth by month's end. Despite improvement in other parts of Pennsylvania, conditions deteriorated to D1 in the southwest corner. Much of West Virginia was under abnormally dry or moderate drought conditions at the start of the month and although conditions improved slightly, areas of D0 and D1 remained. In New Jersey and western Maryland, dry conditions were eased.

As summarized by the Western Regional Climate Center, most locations in the West varied in temperature from well above to well below normal throughout May, averaging near normal for the month. A closed low pressure system mid-month brought helpful but insufficient precipitation to Southern California, the Sierra Nevada, and the western Great Basin. During the last third of May, a persistent low pressure system set up over the Pacific Northwest bringing cool temperatures and ample precipitation to the area. Late May also brought very wet conditions to eastern Montana.

The precipitation helped to alleviate drought conditions in a few locations along the northern tier of the West. Drought conditions worsened in New Mexico, Arizona, and northern California, where below normal precipitation was observed this month. According to the USDM, the area of the West with no drought designation decreased from 20% to 14% in May. Areas in extreme drought status rose from 4% to 6%. This increase occurred in southeastern Colorado and New Mexico. Several large fires occurred throughout the month in Alaska, California, New Mexico, and Arizona. One of the most destructive was the Springs Fire in Ventura County, California. Ignited on May 2, the blaze spread quickly due to strong Santa Ana winds and dry fuels. Over 24,000 acres (9,700 hectares) were consumed, 10 outbuildings destroyed and 12 structures damaged. No homes were destroyed. Radiosonde observations from Boise recorded only 0.05 in (1.3 mm) precipitable water on May 23, the driest atmosphere recorded on any day in Boise since radiosonde observations began.

In Alaska, April?s below normal temperatures continued through the final week of May for the interior. Portions of southern Alaska saw abundant precipitation and snowfall this month. Colder than normal temperatures this spring has slowed melting of ice along the rivers of Alaska?s interior. This has resulted in ice damming and flooding at some locations. On May 27, an ice jam on the Yukon River caused flooding in the town of Galena, prompting evacuation of many of the town's 470 residents.

Pacific Islands: According to reports from National Weather Service offices, the Pacific ENSO Applications Climate Center (PEAC), and partners, conditions varied across the Pacific Islands.

As noted by the National Weather Service office in Honolulu, the month of May produced above average rainfall totals in many areas of the state. This anomalous boost in rainfall during what should be the start of the dry season brought welcome drought relief to portions of Maui county and the Big Island. Extreme drought, or the D3 category in the USDM map, finally eased to the severe drought category, which corresponds to the D2 level. Areas of extreme drought have persisted through five consecutive wet seasons on the Big Island and it ironically took dry season rainfall to remove it. The area of severe drought coverage was also reduced and is currently confined to a portion of the Pohakuloa region in the Hamakua district and the upper elevations of the north Kona and south Kona districts. Former areas of severe drought have been replaced with the moderate drought designation, or D1 level conditions. These areas include most of the south Kohala district, leeward areas of the north Kohala district, and portions of the Kau district. Conditions on the island of Maui also improved but not to the extent as on the Big Island. Extreme drought reduced in coverage but has remained stubbornly in place over the lower southwest slope of Haleakala in the area of Kihei, Kamaole, and Kaonoulu. Areas of severe drought continued to cover lower leeward elevations from Lahaina to Maalaea, and upcountry Maui near Ulupalakua. On Molokai, severe drought persists for agriculture areas served by the Kualapuu reservoir due to continued low supply levels. Reservoir water levels have increased slowly over the past several months but have not risen to pre-drought conditions. Recent improvements to drought conditions may be short-lived as the dry season has started in earnest across the Hawaiian Islands. Minimal amounts of precipitation have fallen since the late May heavy rainfall.

Some drought impacts impacts in Hawaii include the following:

KAUAI.
THERE ARE CURRENTLY NO DROUGHT AREAS ON KAUAI.

OAHU.
THERE ARE CURRENTLY NO DROUGHT AREAS ON OAHU.

MOLOKAI.
SATELLITE-BASED VEGETATION HEALTH DATA SHOW GOOD CONDITIONS OVER
MOST AREAS OF THE ISLAND.  RECENT GROUND OBSERVATIONS CONFIRMED THAT
PASTURES WERE FINE NEAR HOOLEHUA.

THE STATE OF HAWAII DEPARTMENT OF AGRICULTURE MAINTAINED A MANDATORY
REDUCTION IN IRRIGATION WATER CONSUMPTION OF 20 PERCENT FOR FARMERS
SERVED BY THE KUALAPUU RESERVOIR.  THE RESTRICTION WAS REDUCED FROM
30 PERCENT TO 20 PERCENT ON APRIL 2 2013.

LANAI.
SATELLITE-BASED VEGETATION HEALTH DATA SHOW IMPROVEMENTS OVER THE
PAST MONTH...ESPECIALLY IN THE INTERIOR OF THE ISLAND.   NO RECENT
GROUND-BASED OBSERVATIONS HAVE BEEN RECEIVED TO CONFIRM THIS.

MAUI.
RECENT REPORTS INDICATED THAT PASTURES IN THE UPPER ELEVATIONS OF
UPCOUNTRY MAUI HAVE SHOWN MODEST IMPROVEMENTS BUT THE LOWER
ELEVATIONS REMAIN IN POOR CONDITION.  THESE LOWER PASTURES WERE
DESTOCKED MANY MONTHS AGO.  THE MAUI COUNTY DEPARTMENT OF WATER
SUPPLY HAS MAINTAINED THEIR LONG-STANDING REQUEST FOR A 10 PERCENT
REDUCTION IN WATER USE BY CENTRAL AND SOUTH MAUI RESIDENTS.

BIG ISLAND.
NEAR TO ABOVE AVERAGE RAINFALL HAS IMPROVED PASTURE CONDITIONS IN
MANY AREAS BUT THERE ARE STILL AREAS OF STUBBORN DRYNESS AND DROUGHT
IMPACTS.  IN THE SOUTH KONA DISTRICT...THE UPPER ELEVATIONS HAVE
BEEN GETTING JUST LIGHT PRECIPITATION SO FARMERS HAVE STILL BEEN
HAULING WATER TO MEET OPERATIONAL NEEDS.  SIMILARLY...THE LOWER
ELEVATIONS OF THE KAU DISTRICT NEAR SOUTH POINT HAVE BEEN GETTING
SOME RAINFALL BUT NOT ENOUGH TO SHOW SIGNIFICANT IMPROVEMENT. 

SPI values for seven time periods for Hawaiian Island stations, computed by the Honolulu NWS office.
SPI values for seven time periods for Hawaiian Island stations

On other Pacific Islands (maps — Micronesia, Marshall Islands, basinwide), May was drier than normal at Yap, Chuuk, Lukonor, Pohnpei, Kosrae, Majuro, and Pago Pago, and much drier than normal at Kwajalein and Kapingamarangi. May rainfall amounts were below 4 inches at Guam, the northern Marshall Island stations of Kwajalein, Utirik, and Wotje, Ulithi in Yap state, and Rota in the Northern Mariana Islands; May rainfall amounts were below 8 inches at Yap, Saipan, Kapingamarangi, Majuro, and Pago Pago. (This is still the dry season for some of these stations, so even low rainfall amounts may show up as high percent of normals.) Majuro and Pohnpei have been below normal for 10 of the last 12 months, and Kwajalein for 8 of the last 12 months. Twelve-month (June 2012-May 2013) rainfall totals for Koror, Lukonor, Pohnpei, Kwajalein, and Majuro were below normal.

According to NWS reports, extreme dryness continued for parts of the northern Marshall Islands, but showers helped moderate the dry weather in the Commonwealth of the Northern Mariana Islands and Guam. The Republic of the Marshall Islands Cabinet on May 6 issued a state of disaster for the northern Republic of the Marshall Islands (RMI), which was elevated from the previous state of emergency declared on February 19. The drought there was affecting over 6,300 people. As of June 11, the Majuro reservoir was near half full, but severe drought conditions have likely damaged or destroyed agriculture on many atolls to the north with most of the well water in the northern islands too salty for human consumption, as reported by drought assessment teams from the government of the RMI, USAID (report, map), and the media.


X
  • Percent of Normal Precip
  • Precipitation
  • Normals
Pacific Island Percent of 1981-2010 Normal Median Precipitation
Station NameJun
2012
Jul
2012
Aug
2012
Sep
2012
Oct
2012
Nov
2012
Dec
2012
Jan
2013
Feb
2013
Mar
2013
Apr
2013
May
2013
Jun 2012-
May 2013
Chuuk131%141%169%86%128%144%116%99%146%192%49%79%116%
Guam NAS107%66%179%126%92%74%55%128%97%191%45%103%92%
Kapingamarangi179%146%192%147%138%167%74%197%154%199%77%48%124%
Koror95%88%102%111%78%67%103%72%92%56%103%109%84%
Kosrae99%124%144%109%113%119%110%98%146%64%95%76%89%
Kwajalein117%120%95%57%73%45%230%39%17%74%178%29%87%
Lukonor125%82%73%148%74%178%62%60%134%122%71%92%87%
Majuro81%68%87%67%46%154%53%31%152%78%69%65%78%
Pago Pago115%105%59%195%54%181%143%137%87%93%144%66%102%
Pohnpei100%92%96%90%82%109%71%83%54%67%59%52%77%
Saipan118%77%135%101%172%31%89%191%78%127%63%203%111%
Yap99%84%128%187%140%121%102%90%113%130%50%69%109%
Pacific Island Precipitation (Inches)
Station NameJun
2012
Jul
2012
Aug
2012
Sep
2012
Oct
2012
Nov
2012
Dec
2012
Jan
2013
Feb
2013
Mar
2013
Apr
2013
May
2013
Jun 2012-
May 2013
Chuuk15.2716.9221.7810.0414.6815.3013.0910.0010.6016.006.118.93158.72
Guam NAS6.636.7426.4215.9810.565.452.815.122.953.951.143.5191.26
Kapingamarangi24.6820.6515.5714.5611.3215.447.2518.0214.2522.7910.515.84180.88
Koror16.5416.3613.7213.019.237.6811.527.297.914.137.5712.87127.83
Kosrae14.5618.5520.4615.5212.3316.4917.7516.2718.8910.2016.7113.41191.14
Kwajalein8.0811.839.236.178.185.0915.331.220.461.739.341.9778.63
Lukonor14.5313.0810.2615.028.3916.187.005.0511.9311.348.0610.77131.61
Majuro8.897.5410.157.475.8420.696.092.4210.445.136.466.6097.72
Pago Pago6.135.843.1912.734.9918.3418.3118.2710.489.9713.526.35128.12
Pohnpei14.8614.2113.6211.2712.5916.1811.3710.885.148.7810.9210.44140.26
Saipan4.266.8617.7310.2418.311.753.444.832.032.401.654.8278.32
Yap11.9512.7418.9225.1917.0810.678.685.725.865.952.815.41130.98
Pacific Island 1981-2010 Normal Median Precipitation (Inches)
Station NameJun
2012
Jul
2012
Aug
2012
Sep
2012
Oct
2012
Nov
2012
Dec
2012
Jan
2013
Feb
2013
Mar
2013
Apr
2013
May
2013
Jun 2012-
May 2013
Chuuk11.6611.9812.8611.7111.5110.6111.2510.107.258.3212.4711.30136.77
Guam NAS6.1810.1414.7412.6611.447.385.114.013.032.072.533.4099.09
Kapingamarangi13.7814.158.139.938.199.279.849.159.2711.4313.6412.08145.85
Koror17.4818.5313.5011.7711.8411.3911.1610.188.567.447.3211.83152.90
Kosrae14.6414.9114.2214.2210.9413.8316.1116.6712.9316.0617.5117.75213.87
Kwajalein6.939.879.7410.7411.1811.286.663.162.642.355.266.7290.41
Lukonor11.6515.9314.0410.1511.329.0811.278.418.939.2611.3111.69151.36
Majuro11.0111.1711.6911.1712.7313.4411.397.746.886.589.4210.11125.25
Pago Pago5.335.555.386.539.2610.1412.8413.3412.0010.689.399.66125.57
Pohnpei14.8115.4314.2612.5515.2714.8316.0813.189.5513.1718.4119.96182.36
Saipan3.628.9113.1310.0910.625.613.852.532.591.892.632.3870.25
Yap12.0415.0814.8213.5012.188.838.516.395.194.565.637.85120.31

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

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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

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Drought Indicators
The following indicators illustrate the drought conditions this month:

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

Citing This Report

NOAA National Climatic Data Center, State of the Climate: Drought for May 2013, published online June 2013, retrieved on December 20, 2014 from http://www.ncdc.noaa.gov/sotc/drought/2013/5.