California and National Drought Summary for November 8, 2016
Summary
November 10, 2016 - Mild weather once again dominated the majority of the U.S. this past week. Temperatures of at least 10 degrees warmer than normal dominated much of the Plains, Midwest, and Mid-South. Near to slightly below-normal temperatures were confined to New England and south Florida. The drought-stricken areas of the Southeast, southern California, the Intermountain West, and the northwestern Plains received little, if any, precipitation resulting in the persistence or deterioration of drought conditions in these areas. Meanwhile, the coastal Northwest, the south-central U.S., parts of the Midwest, and New England saw rainfall with the passage of a cold front through those areas.The Northeast
Rainfall totals in the Northeast last week were predominantly near to slightly below normal resulting in status quo for the majority of the region. Western New York saw a removal of severe drought (D2) near Lake Erie as rains over the last month have been enough to ease drought in this area. Southeastern New York and eastern Pennsylvania have missed out on the heaviest rains causing low streamflows and resulting in the expansion of D0.Midwest and Lower Ohio Valley
Much of the Midwest continued to remain drought-free, though southern Ohio saw an expansion of D0. Continued rainfall shortages combined with above-normal temperatures have caused continued dryness across Kentucky and Tennessee. Severe drought (D2) was introduced into south-central Kentucky and moderate drought (D1) was expanded to the western part of the state due to precipitation deficits, wildfire activity, and low soil moisture. In Tennessee, severe drought (D2) was expanded in the central part of the state and exceptional drought (D4) crept eastward.The Southeast
Once again, the drought-stricken areas of Alabama and Georgia were warm and dry with temperatures up to 10 degrees warmer than normal and precipitation at or near zero. Exceptional drought (D4) was introduced along the Mississippi and Alabama border and was also expanded in eastern Alabama, northern Georgia, and western North Carolina. Other changes in the Southeast include a southward expansion of severe drought (D2) in Alabama; a southeastward expansion of abnormal dryness (D0) and moderate drought (D1) and a southwest expansion of extreme drought (D3) in Georgia; a slight southward expansion of abnormal dryness (D0) and moderate drought (D1) in South Carolina; and a general one-class deterioration of drought conditions in western North Carolina. Areas of abnormally dry conditions (D0) were introduced into parts of western Virginia and in the Florida Panhandle.The South
Much of the South received precipitation over the last week. In the driest regions, rainfall totals were not enough to overcome long-term deficits and resulted in the expansion of drought. Severe drought (D2) was expanded across northern Louisiana, southwest Arkansas, and southeastern Oklahoma. Moderate drought (D1) also expanded to cover the remainder of the Arkansas-Louisiana border. In general, east Texas saw a one-category reduction in drought along the western fringes of the drought areas in that part of the state. The parts of the Panhandle and south Texas that missed the heaviest rains saw slight expansions of moderate drought (D1). Mississippi remained status quo.The Plains
Most of last week’s rain stayed to the east of the regions’ drought-inflicted areas. Temperatures ranging from 8 to 16 degrees above normal caused continued drying in these regions and resulted in an expansion of moderate drought (D1) over southwest Kansas and abnormally dry (D0) conditions across north central South Dakota and south-central North Dakota.The West
Changes in the West this week were mixed. Abnormal dryness (D0) expanded westward in the Upper Colorado River Basin over western Colorado, eastern Utah, and south-central Wyoming in response to warmer-than-normal temperatures and short-term precipitation deficits. Colorado also saw a south and southwestward expansion of moderate drought (D1) due to the continued dryness in the region and impacts on soil moisture and vegetation. A re-examination of data due to rains over the last 30 days resulted in a trimming of moderate (D1) and severe (D2) drought over northeast California and northwest Nevada. These rains have been enough to improve long-term rainfall deficits, streamflow, and soil moisture. Likewise, a one category improvement was made in drought conditions over western Wyoming,Alaska, Hawaii, and Puerto Rico
Outside of the CONUS, Alaska saw a removal of D0 from the southeastern part of the state as streamflow has been increasing and reservoirs have been filling. Hawaii saw a deterioration in drought conditions with an expansion of moderate (D1) and severe (D2) drought in Kauai and an increase in abnormally dry conditions in Oahu, Molokai, Lanai, Maui, and the Big Island due to rainfall shortages and agricultural impacts. Puerto Rico remains at status quo for the week.Looking Ahead
The National Weather Service medium range forecast calls for continued warmth and dryness over much of the interior U.S. The highest temperature anomalies are expected over the western and central states while East Coast temperatures are forecast to return to more seasonable values. The highest probabilities for precipitation once again is in the Northwest. Forecast models also indicate a possibility for rain along parts of the Gulf and East Coast.Author(s):
Deborah Bathke, National Drought Mitigation Center
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 DroughtD2 ... 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)
Source: National Drought Mitigation Center
