A Mix of Improvements, Degradations to Drought Depiction
Despite an overall drier, quieter weather pattern nationwide, beneficial rain and snow occurred in localized areas last week, leading to some improvements to the drought depiction.
West
There were the haves and the have nots in terms of precipitation throughout the West this week.
Areas of moderate to isolated heavy rain and snow affected the Sierra Nevada, southwestern California, western Washington and some of the higher elevations across Arizona, Utah, eastern Nevada and southern Nevada. The Olympic Peninsula in Washington and parts of the Sierra Nevada reported anywhere from 3 to 8 inches of liquid precipitation for the week! Moderate drought (D1) was removed from a portion of northwestern Washington.
However, the rest of the Western region stayed fairly dry, recording several tenths of an inch or less. Like the South, parts of New Mexico are experiencing rapid dryness and drought, and a large part of the state deteriorated by one category this week. This includes a larger area of extreme drought (D3) along the southern tier of the state, with a small area of exceptional drought (D4) that introduced in the state’s southwestern interior.
The rest of the region remained status quo this week. While no intensification occurred, there is still a broad area of extreme and exceptional drought (D3-D4) that persists across southern California, southern Nevada and much of Arizona. From central portions of Utah and Nevada southward to the Mexican border and southern California, less than half of normal precipitation has fallen since mid-December, with the lowest totals extending across the southern Four Corners area.
High Plains
Light to moderate rain and snow fell over parts of the western High Plains last week, while fairly dry weather persisted across the rest of the region.
Abnormal dryness and moderate to extreme drought (D1-D3) were reduced in coverage across parts of Wyoming, adjacent northern Colorado, north-central Nebraska and a small part of northwestern Kansas. Recent precipitation and some localized heavy rain this week allowed coverage of abnormal dryness and moderate drought (D1) to shrink across eastern Kansas.
At the same time, dryness and moderate drought (D1) worsened across parts of southern Colorado into western and central Kansas. The depiction across the Dakotas did not change this week.
Midwest
Precipitation was hit-or-miss across the Midwest last week. It stayed fairly dry in northwestern Ohio, central and southern Indiana and adjacent Illinois. Moderate to heavy precipitation occurred in northwestern Indiana, central and northern Illinois, central and southern Iowa and much of Missouri. Parts of the Great Lakes also saw beneficial moisture last week, but most precipitation missed Minnesota. Moderate precipitation covered most of Kentucky, which is one of two states completely free of dryness and drought.
Abnormal dryness and moderate drought (D1) shrunk in coverage across most of Iowa and Missouri, with severe drought (D2) shrinking across northeastern Missouri into west-central Illinois. West-central Minnesota and east-central Illinois saw a small area of severe drought (D2) added this week. The rest of the region remained status quo.
South
A low pressure system brought beneficial moisture to eastern portions of the South this week. Western areas, however, stayed largely dry.
Most of the areas that picked up rain this week were already free of drought, including Louisiana which is one of two states completely free of dryness and drought. Arkansas, Mississippi and Tennessee all remained status quo this week. Dryness and moderate drought did shrink in coverage for northern Texas and southern Oklahoma. The southern Red River Valley saw dryness and moderate to severe drought (D1-D2) decrease.
Moderate drought (D1) did expand north across northern Oklahoma though. Dryness and drought worsened as well from the San Antonio area up into the Hill County of Texas. This includes a new area of exceptional drought (D4) that was added. With dry weather, increasing temperatures and periods of high winds, conditions could deteriorate rapidly across central and northwestern Texas into parts of adjacent Oklahoma.
Southeast
Near or above normal precipitation was observed across most of the Southeast last week. The exception was far northern areas (Virginia) and far southern areas (central/southern Florida Peninsula).
Beneficial moisture led to improvement of dryness and drought for isolated parts of Alabama, most of Georgia and parts of the Carolinas. This includes widespread removal of abnormal dryness from southern Georgia. An area of severe drought (D2) decreased in coverage across the eastern Carolinas.
Conversely, there was some degradations to dryness and moderate drought (D1) in northern Virginia, parts of western North Carolina and northernmost Georgia. Central and southern parts of the Florida Peninsula also saw an expansion of dryness and moderate to severe drought (D1-D2).
Northeast
Moderate to heavy rain fell on the eastern tier of the Northeast region last week, with 1 to 2 inches reported in areas. Meanwhile, amounts were more variable farther west.
Dryness and drought eased over parts of southern and eastern New England, including the removal of severe drought (D2) in interior southern New England. Some isolated improvements were also observed over central Pennsylvania.
At the same time, there was the expansion of abnormal dryness and moderate drought (D1) over northwestern Maryland and northern West Virginia. Despite the increase in precipitation, the southern and eastern parts of the region remain the driest, with extreme drought (D3) covering southeastern New Jersey and severe drought (D2) in place from central Maryland and Delaware northward through southeastern Pennsylvania and most of southern New Jersey.
Looking Ahead
The Western U.S. will see a series of weather systems move across the region this week. This will bring heavy rain and mountain snow to the Northwest, the northern half of California, the northern Rockies and parts of the Great Basin. Widespread improvements are likely in most areas this week as a result. While missing out on the heaviest precipitation, southern California into the Four Corners will also likely see rain and mountain snow at times. This could lead to some improvements to dryness and drought or at least slow down the degradation that has been occurring this winter.
As these storms in the West move east, they will likely bring precipitation to the rest of the U.S. The greatest chance for precipitation will occur by the middle to end of the forecast period when a severe weather event looks to take place. In addition to dangerous thunderstorms, this system also looks to bring heavy rain. Improvements will likely occur in the Midwest, eastern parts of the Southern region, Southeast and Northeast. The High Plains and western parts of Southern region likely miss out though and degradation of dryness and drought will likely take place.
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Source: U.S. Drought Monitor
