This week's National Drought Monitor reflects locally heavy rain provided drought relief to the south-central U.S., while a late-season Pacific storm brought beneficial precipitation to much of the west. However, unseasonable warmth led to high evapotranspiration rates and crop water demands across the Midwest and Northern Plains.
Drought areas of the Midwest — which extend from northwestern Iowa into northern portions of Minnesota and Michigan’s Upper Peninsula — reported record-setting warmth (temperatures 25 to 30°F, or more, above normal) during the past week, states the monitor. :Showers were mainly light (0.5 inch or less, although up to an inch fell in central Wisconsin) and offered little if any drought relief. Although no changes were made to the drought designation in the Midwest this week, the ongoing unseasonable warmth has highlighted the need for rain over the upcoming weeks to prevent drought intensification or expansion," it states.
In the Central and Northern Plains, the monitor states temperatures averaging 20 to 25°F above normal across most of the region. "Drought relief was noted in southeastern Kansas, where 1 to more than 3 inches of rain fell," it says. "In western and northern portions of Kansas, where 90-day rainfall has totaled less than 50% of normal, small increases in drought were made to reflect the impacts of the warmth and dryness. Farther north, the latest 3- and 6-month Standardized Precipitation Indices (SPI) as well as input from the field supported the introduction of Moderate Drought (D1) in southwestern South Dakota. Likewise, additional assessment led to a small reduction of Abnormal Dryness (D0) in southern portions of the state. Elsewhere, no changes were made to the region’s drought designation, although the unseasonable warmth has led to early crop development and increased water demands."
In the Southern Plains, heavy rain resulted in drought reduction, except for in southern Texas and western portions of Kansas and Oklahoma, where more rain is needed. "Over the past 6 months, much of southern Texas has reported less than 60% of normal rainfall, with some areas below 50%; coupled with additional assessment from the field, Severe Drought (D3) was expanded across this portion of the state. Farther north, there were no changes made to the current drought depiction in northern Texas and western Oklahoma as rain was overspreading the area as of mid-week," it states.
In its outlook, the monitor states, "A slow-moving disturbance will produce locally heavy rain across the Mississippi River Valley, while light to moderate showers over the south-central Plains gradually diminish. As the system tracks east, beneficial rain will break out across the Southeast and southern Mid-Atlantic, although mostly dry conditions will prevail in Florida and the Northeast. Meanwhile, another round of rain and mountain snow is expected from southern California northward into the Northwest and northern Rockies. Some precipitation may reach the central Great Basin, although amounts are expected to be light. Mostly dry conditions will persist in the Four Corners Region."
The CPC 6-10 day forecast for March 27-31 calls for above-normal temperatures across most of the nation, with cooler-than-normal conditions confined to the Pacific Coast states. "Below-normal precipitation is anticipated from the Mid-Atlantic to the eastern Gulf Coast, and from the central Rockies into the Southwest. Conversely, wetter-than-normal weather is expected from southern Texas into the Great Lakes and northern New England and across the Northwest," it adds.