Country’s midsection receives good dose of rain

Heavy rain again fell on parts of the nation’s midsection along a strong quasi-stationary front during the past week.

A swath of heavy amounts (over 2 inches) extended from central Texas northeastward through eastern Oklahoma, southeastern Kansas, northwestern Arkansas, and much of Missouri. The largest amounts (4 to locally 8 inches) covered a band from the Middle Red River (south) Valley into central Missouri. Farther north, 2 to 4 inches also soaked much of southeastern Nebraska and eastern Iowa.

More widely scattered amounts of 2 to 4 inches affected southeastern Texas. Existing dryness and drought improved in most areas because of heavy precipitation, in addition to portions of the central Rockies where less robust precipitation compounded frequently above-normal totals during the past several weeks.

Meanwhile, subnormal amounts propelled intensifying drought and dryness along parts of southern Texas, parts of the central and northern Plains, and both the northern and southern tiers of the Rockies and adjacent lower elevations. In many areas that observed worsening conditions, unusually warm weather (temperatures generally 3 to 6 degrees Fahrenheit above normal) have prevailed for the past four weeks, particularly across the southern half of the Great Plains.

The U.S. Drought Monitor is jointly produced by the National Drought Mitigation Center at the University of Nebraska-Lincoln, the U.S. Department of Agriculture and the National Oceanic Atmospheric Administration. (Map courtesy of NDMC.)

South

Entrenched drought is limited to areas from east-central Texas and central Oklahoma westward, despite heavy precipitation in a narrow band from the Middle Red River Valley into west-central Texas. Significant eastward expansion of dryness and drought was prominent across east-central Texas, with smaller areas of deterioration noted elsewhere.

For the past 90 days, precipitation totals have been 4 to 7 inches below normal across a broad area from south-central through east-central Texas (specifically, from Walker, Grimes, and Brazos Counties southwestward through Lavaca County and some adjacent areas).

Midwest

Conditions varied considerably across this region, as has been the case for the past several weeks. Moderate to heavy rain (generally over 1.5 inches) fell on a sizeable area covering most of Missouri, central and eastern Iowa and southeastern Minnesota.

The heaviest amounts (4 to 8 inches) were fairly widespread across central and southwestern Missouri. Any dryness or drought in most of these areas improved notably with the exception of a portion of interior northeastern Iowa, where 60- and 90-day amounts remained below normal.

This week’s deluging rainfall in Missouri removed most of the large abnormally dry area that had covered most central, northern, and western parts of the state. Drought coverage increased in northern Minnesota, which was missed by the heavier precipitation. In the far northwestern part of the state, areas near the Canadian border have received only about half of normal precipitation for the past one to two months.

High Plains

Moderate to locally heavy precipitation (over 0.5 inch, with isolated amounts topping 2 inches) fell on some of the higher elevations of Colorado and Wyoming. On the other side of the region, heavy rains, amounting to several inches in some places, doused southeastern Kansas.

Elsewhere, amounts exceeded 0.5 inch in several scattered areas mostly in the High Plains and central Kansas, but most other locales recorded a few tenths at best. Dryness and drought broadly improved by one category across a broad section of southeastern Kansas, and more localized improvement was noted in some of the wetter areas of the higher elevations.

Conditions were mostly unchanged across the rest of the High Plains, but a few localized areas worsened enough to increase one category on the map. Extreme drought continued to affect much of southeastern Colorado and portions of adjacent southwestern South Dakota and western Nebraska.

Less than half of normal rainfall was reported over the past 90 days in some areas of west-central and north-central South Dakota, northeastern and southeastern Nebraska, and central through southern Kansas.

West

Moderate to locally heavy rain (generally 1 to 2.5 inches) fell on south-central Montana, but only scattered to isolated moderate amounts approaching an inch were noted elsewhere in the state.

In other locations, several tenths of an inch of precipitation fell on and near some of the higher elevations, but most places reported little or none. Despite the moisture observed in part of the state, the eastern and western sections of Montana saw some D0 and D1 expansion, though the more severely affected areas (D2 to D3) were unchanged.

Along the southern tier of the region, expansion of the broad-scale severe to extreme drought was noted in parts of New Mexico. The most intense levels of drought (D3 and D4) now cover a broad area including western New Mexico and the Texas Big Bend into south-central parts of the state.

Looking ahead

During April 23 to 28, substantial portions of the contiguous United States are expecting at least moderate precipitation (several tenths), with scattered heavy amounts over 2 inches. This includes a swath from northwestern Wyoming across southern Montana and most of the Dakotas.

Heavy amounts could be most widespread in the Red River (south) Valley, central Oklahoma, and from the central Plains into Iowa. In addition, most of the central and southern Great Plains should receive several tenths of an inch to near 2 inches. In the West, a few tenths to about 1.5 inches of precipitation are forecast for western Montana.

Meanwhile, little or no precipitation is forecast for most of the Four Corners region and southern Texas.

Daily high temperatures are expected to average 8 to 10 degrees above normal and many locations in and around South Dakota.

The Climate Prediction Center’s six- to 10-day outlook valid April 29 to May 3, favors wetter than normal conditions southeastern Rockies eastward through the Middle and Lower Mississippi. Meanwhile, subnormal precipitation is most likely across the northern Plains, central and western Rockies, and the Intermountain West.

Warm weather should prevail across the contiguous United States outside the southern High Plains and adjacent Rockies. The greatest odds for warmth extend from California and the Great Basin through the northern Rockies and Intermountain West.

Richard Tinker works with the National Oceanic Atmospheric Administration, National Weather Service, Climate Prediction Center, and National Centers for Environmental Prediction.