Several regions across the U.S. this Drought Monitor week have seen one-category degradations, crossing most of Texas and also affecting northern Mississippi and a pocket of Nevada; meanwhile, improvements were noted in the Northwest, mostly centered on Washington.
David Simeral of the Western Regional Climate Center says most of the significant precipitation accumulations were restricted to drought-free areas of Florida, northern Rockies of Montana, and North Cascades of Washington.
Snow showers and unseasonably cold temperatures persisted across the northern tier, while in the West, an overall dry pattern prevailed with above normal temperatures, he said.
Midwest and Plains region
Temps plunged in the upper Midwest, continuing a pattern of cold conditions in the area. Snow continues to fall in portions of the Great Lakes region and in the High Plains, though drought conditions appear unchanged for the week.
One exception is a small patch of drought in the southeast corner of South Dakota, where a one-category degradation was noted.
Farther south, extreme eastern Oklahoma received about one inch of precipitation in a few isolated pockets, Simeral reports. In western portions of Oklahoma, severe, extreme and exceptional drought has expanded. Moderate drought expanded in Kansas.
Arkansas, southern Louisiana, and central Mississippi saw marginal rains last week while Texas continues to suffer from widespread deterioration of conditions across the western two-thirds of the state.
Looking at the long-term precipitation situation using the National Climatic Data Center Climatological Rankings Tool, Simeral says the Texas Climate Division high plains and low rolling plains both rank first driest on record for the 36-month period from March 2011 to February 2014.
Temperatures were below normal across most of the region during the past week, he adds.
Storms brought snow to the North Cascades and northern Rockies, as well as some portions of Colorado. Meanwhile, dry conditions continued for the rest of the West.
According to the Natural Resource Conservation Service SNOTEL network, Simeral reports, basin average precipitation was below normal across the mountains of Oregon, northern Nevada, Arizona, and New Mexico.
In northwestern Nevada, severely reduced water allocations for agriculture and long-term precipitation deficits led to expansion of exceptional drought. In southeastern Colorado, strong winds continued to degrade topsoil conditions and affect wheat crops leading to expansion of severe drought in Baca County.
In New Mexico, short-term precipitation deficits and dry soil conditions led to expansion of extreme drought in south-central New Mexico and expansion of moderate drought in southeastern New Mexico.
California remained mostly unchanged, save for small pockets of degradation in the far southern tip and along the coast in Santa Barbara and Ventura Counties.
Source: U.S. Drought Monitor