National Drought Summary -- August 14, 2012

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National Drought Summary -- August 14, 2012

The discussion in the Looking Ahead section is simply a description of what the official national guidance from the National Weather Service (NWS) National Centers for Environmental Prediction is depicting for current areas of dryness and drought. The NWS forecast products utilized include the HPC 5-day QPF and 5-day Mean Temperature progs, the 6-10 Day Outlooks of Temperature and Precipitation Probability, and the 8-14 Day Outlooks of Temperature and Precipitation Probability, valid as of late Wednesday afternoon of the USDM release week. The NWS forecast web page used for this section is: http://www.cpc.ncep.noaa.gov/products/forecasts/. This U.S. Drought Monitor week saw a few notable improvements and some serious degradation.  One storm dumped much needed rain through the Midwest improving the drought conditions there from Iowa through Ohio.  Other areas, such as the Southern and Central Plains, were not as lucky and continued to dry out.  Another changed that helped alleviate the drought in some locations was the easing of the heat.  Many areas from the Midwest to the South saw highs in the 80˚s F this week instead of the 100˚s F they had been experiencing.  As of last week, 87% of the U.S. corn crop, 85% of soybeans, 63% of hay, and 72% of cattle areas were experiencing drought.  Over half of the corn and soybean areas are experiencing Extreme (D3) to Exceptional (D4) Drought.  This has led to both reduced yields and earlier harvests. The Southeast: Rains in the Southeast this helped to improve drought conditions through Alabama, Georgia, and South Carolina.  Exceptional Drought (D4) was eradicated in Alabama and reduced in Georgia while Extreme (D3), Severe (D2), and Moderate (D1) Drought were all reduced, as was Abnormal Dryness (D0).  In South Carolina, improvements in areas of Extreme (D3), Severe (D2), Moderate (D1) Drought and Abnormal Dryness (D0) were experienced. Minor changes were made improving Abnormal Dryness (D0) in parts of the south, and expanding Abnormal Dryness (D0) in the north of North Carolina. The Northeast and Mid-Atlantic: Most of this area received enough precipitation that drought conditions held status quo with minor reductions in Abnormal Dryness (D0) in Maine.    The South and Southern Plains:  In Oklahoma, large swaths of Exceptional Drought (D4) were introduced as the impact of the lack of rain and hot temperatures parched the state’s soil moisture.  Texas also saw minor deterioration of conditions with the expansion of Extreme Drought (D3) in the south, Severe Drought (D2) in areas of the center and north, and in Moderate Drought (D1) in the west.  In Louisiana, Severe Drought (D3) expanded in the north. The Central and Northern Plains and Midwest: Widespread rains in the Midwest alleviated some D1-D4 Drought as well as Abnormal Dryness (D0) in a swath from central Iowa, across northern and central Illinois and Indiana, and into western Ohio and southern Michigan.  North and South Dakota also experienced beneficial precipitation, alleviating Abnormal Dryness (D0). Exceptional Drought (D4) expanded in the western and central parts of Nebraska and through central and eastern Kansas and into western and central Missouri. The West: Areas of Exceptional (D4) and Extreme (D3) Drought generally expanded in Colorado where rain showers were largely absent again this week.  In Idaho, Moderate Drought (D1) and Abnormal Dryness (D0) expanded and wildfires were on the rise. Other areas of the West remained status quo. Hawaii, Alaska and Puerto Rico: Drought conditions remained unchanged in Alaska and Puerto Rico and Hawaii this week. Looking Ahead: During the August 16 - 20, 2012 time period, there is an enhanced probability of precipitation from the extreme South, through the Southeast and mid-Atlantic and through New England. From the West through the Great Lakes, there is a suppressed chance of precipitation.  Below normal temperatures are expected from the center of the country eastward.  The West is expected to see above normal temperatures. For the ensuing 5 days (August 21 - 25, 2012), the odds favor normal to below normal temperatures from just east of the Rockies to the east coast and also along the Pacific Coast.  In a narrow band along the Rockies and in New England, the odds favor warmer than normal temperatures. Above normal precipitation is expected from New England, through the South and into the extreme Southern Plains.  Normal to below normal precipitation is expected over the rest of the lower 48 states.  In Alaska, temperatures are expected to be below normal in the south and above normal along the Arctic Ocean while precipitation is expected to be above normal in the south and below normal along the Arctic Ocean. Author: Michael Brewer, National Climatic Data Center, NOAA

Dryness Categories

D0 ... Abnormally Dry ... used for areas showing dryness but not yet in drought, or for areas recovering from drought. Drought Intensity Categories D1 ... Moderate Drought D2 ... Severe Drought D3 ... Extreme Drought D4 ... Exceptional Drought Drought or Dryness Types S ... Short-Term, typically <6 months (e.g. agricultural, grasslands) L ... Long-Term, typically >6 months (e.g. hydrology, ecology) Updated August 15, 2012