Sharp Divide in Precipitation Leads to Mixed Results to Drought

There was a significant divide in precipitation and temperatures across the U.S. during the monitoring week. The eastern half of the nation remained unusually cool and saw beneficial moisture, while unseasonably hot and dry weather baked the western half. The lack of moisture and hot temperatures, paired with periods of blustery winds, triggered extreme fire danger at times.

West

The West was characterized by unseasonable warmth and widespread dryness across the Pacific Coast and Great Basin, contrasted by cooler, more active conditions in the Rocky Mountains. Coastal and interior basin states recorded less than one-tenth inch of rain.

Exceptional drought (D4) was expanded in southern Idaho, while extreme drought (D3) was introduced in Oregon and expanded in Montana, Idaho and Nevada. Moderate to severe drought (D1-D2) was expanded in Oregon, Idaho and Montana. Severe drought (D2) was also introduced in northern Washington and expanded in northern Nevada. Conditions deteriorated over parts of southwestern Washington and northwestern Oregon, resulting in the expansion of abnormal dryness (D0) in these areas.

Conversely, localized moisture resulted in improvements to abnormal dryness and moderate to severe drought (D0-D2) in southern Arizona. Improvements to moderate drought (D1) occurred in parts of western Nevada.

High Plains

Eastern portions of the High Plains region remained under a persistent late-spring chill this week. However, this area was also exceptionally dry, receiving less than 0.05 inches of rain. At the same time, the western High Plains experienced unseasonable warmth. This warmth was accompanied by an active moisture corridor through the southern High Plains. While northern and eastern portions of the High Plains were dry, portions of Colorado and adjacent areas of southeastern Wyoming and northwestern Kansas recorded 0.7 to 1.6 inches of rain.

Persistent dryness resulted in the expansion of exceptional drought (D4) in southwest Nebraska. Deepening drought impacted many other areas of Nebraska, with 88% of the Cornhusker State now experiencing some level of drought. Moderate to extreme drought (D1-D3) were expanded in northeastern Wyoming, South Dakota and Kansas.

In contrast, the above normal precipitation resulted in the removal of exceptional drought (D4) and reduction of extreme drought (D3) in Wyoming. Improvements were also made to severe to exceptional drought (D2-D4) in Colorado, with a reduction of severe to extreme drought (D2-D3) in western Kansas.

Midwest

Like the High Plains region, there was a mix of temperature and precipitation throughout the Midwest region this week. Temperatures were unseasonably cold across northern portions of the region, especially along the northern border of Minnesota and Wisconsin. More seasonable temperatures were observed in southern parts, including Missouri and Kentucky.

Precipitation was notably sparse across the northern half of the region, including Minnesota, Wisconsin, Iowa and Michigan. Here, totals remained under one-tenth inch. The southern tier saw much more active weather, with precipitation totals ranging from 1.5 to 3 inches.

Moderate to extreme drought (D1-D3) was expanded in portions of central and eastern Kentucky, where rainfall amounts were below normal. Abnormal dryness was also expanded in parts of Minnesota, western Iowa, southern Missouri and in pockets of Indiana and Ohio.

On the contrary, the active weather led to the reduction of severe to extreme drought (D2-D3) in western parts of Kentucky.

South

The Southern region experienced a stark contrast in both precipitation and temperatures during the week, defined by torrential Gulf Coast rains and a significant late-spring chill across the interior. Precipitation was most intense across the central Gulf Coast, particularly in Louisiana and southern Mississippi. Here, precipitation totals for the week reached 7 to 9+ inches. Conversely, drier conditions prevailed in West Texas, Oklahoma and much of the Tennessee Valley.

Exceptional drought (D4) was introduced in southwestern Oklahoma and from the Texas Panhandle into northwestern Oklahoma. Exceptional drought (D4) was also expanded in parts of Arkansas and northern Mississippi. Extreme drought (D3) expanded in northern portions of Texas and western Oklahoma.

As a result of the more active weather, moderate to exceptional drought (D1-D4) was reduced in southern and eastern portions of Texas and in parts of Louisiana, Mississippi and southern Tennessee.

Southeast

Much of the Southeast experienced below normal temperatures this week. The exception was Florida, Georgia and parts of Alabama and South Carolina, where temperatures ended up above the average for this time of year. Beneficial moisture was recorded across much of Alabama and portions of Georgia and the Florida Panhandle. These spots ended up with 1.5 to 3.0 inches. There were even some localized amounts of 4 to 7+ inches. Weekly rainfall totals of 1.5 to 3.0 inches also extended from the southern Appalachian region to south-central North Carolina.

Extreme drought (D3) was expanded in central and southern portions of Viriginia and slightly into a northern pocket of North Carolina.

Meanwhile, exceptional drought (D4) was removed from south-central North Carolina and northeastern Georgia and improved in the Florida Panhandle. Extreme drought (D3) improved across parts of northern Florida, Alabama, Georgia and the Carolinas.

Northeast

The Northeast region experienced a pronounced late-spring chill coupled with a sharp divide in precipitation. Northern and western parts of the region featured a surplus of beneficial moisture, while southern areas stayed largely dry. Heavy precipitation was concentrated in western New York, northwestern Pennsylvania and much of main, where rainfall amounts ranged from 0.5 to 1.8 inches above normal. Conversely, precipitation deficits of 0.5 to 1.5 inches below normal in southern portions.

Severe drought (D2) was expanded in northern Massachusetts, Delaware and southern portions of Pennsylvania, New Jersey and West Viriginia. Moderate drought (D1) was also expanded in Massachusetts, Rhode Island, Connecticut and southern Pennsylvania this week.

Moderate to severe drought and abnormal dryness (D0-D2) improved in Maine.

Looking Ahead

The U.S. will experience a pronounced weather divide between the West and East over the next week. A strong high pressure system is expected to bring unusually hot conditions across the western states, with temperatures climbing well above seasonal averages and potentially setting or tying record highs. This heat will gradually expand into the central Plains by the middle of the week. There will also be periods of rain and mountain snow that impacts the Northwest and Rockies thanks to a series of weather system. This could help abnormally dry and drought conditions or at least slow the drying out process. The Southwest, however, will remain largely dry over the next week, which could continue to worsen drought.

Meanwhile, the eastern half of the country will remain cooler and more unsettled. Multiple frontal systems are forecast to trigger repeated rounds of showers and thunderstorms from the Midwest through the Atlantic Coast, keeping temperatures near or below normal. Improvements to drought conditions will likely occur.

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Source: U.S. Drought Monitor