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MONITOR

Latest drought monitor over the midwest

OUTLOOKs



Monthly drought outlook


CHANGE OVER TIME

One Week US Drought Monitor Class Change

PRECIP. NEEDED TO END

Amount of precipitation needed to end drought

PALMER DROUGHT INDEX

Drought severity index by division

DEPARTURES

4 month precipitation departures

VEGETATION (VegDri)

Vegetation Drought Response Index (VegDRI), complete, Iowa

STANDARD PRECIP INDEX

Standard precipitation index

TOPSOIL MOISTURE

USDA Topsoil Moisture by Short-VeryShort

STATISTICS

Week Date None Abnormally Dry Moderate Severe Extreme Exceptional DSCI
Current 2024-05-21 66.42 33.58 20.91 0.00 0.00 0.00 54
Last Week 2024-05-14 52.54 47.46 27.43 16.09 0.00 0.00 91
Three Months Ago 2024-02-20 4.19 95.81 78.22 56.37 18.58 0.00 249
Start of Calendar Year 2024-01-02 2.77 97.23 83.41 65.09 35.18 0.00 281
Start of Water Year 2023-09-26 0.01 99.99 95.65 67.41 25.00 1.17 289
One Year Ago 2023-05-16 45.62 54.38 25.78 2.44 0.65 0.00 83

DISCUSSION

This U.S. Drought Monitor (USDM) week saw widespread improvement in drought-related conditions on the map across areas of the South, Plains, Midwest, Mid-Atlantic, and the West. In the Plains and Midwest, locally heavy rainfall accumulations (up to 7 inches) were observed in drought-affected areas of Oklahoma, Kansas, Nebraska, Missouri, and Iowa leading to continued improvements of conditions on the ground (vegetation health, soil moisture, surface water) as well as reductions in the longer-term precipitation deficits. Likewise, above-normal precipitation during the past several months led to removal of areas of drought on the map in Michigan’s Upper Peninsula as well as in southern Wisconsin. In the South, isolated areas of central and west-central Texas saw minor improvements in response to recent rains and improving conditions during the past 30-day period. In the Mid-Atlantic, 1-6-inch accumulations were observed in areas of North Carolina and Virginia this week leading to removal of areas of Abnormally Dry (D0). Out West, some minor improvements were logged in central and northern Arizona where precipitation has been above normal since January 1. In southeastern Montana, recent rains erased Water Year (since October 1) deficits and have improved soil moisture conditions and vegetation health. Across the border in the Bighorn Mountains of north-central Wyoming, areas of Moderate Drought (D1) were removed in response to above-normal snowpack conditions observed in its associated drainage basins. In California, the state’s reservoirs are above normal levels moving into the dry season with the state’s two largest reservoirs (Lake Shasta and Lake Oroville) at 115% and 126% of their historical average for the date (May 21), respectively. In the Southwest, Lake Powell is currently 33% full (58% of typical storage level for the date) and Lake Mead is 35% full (62% of average) with the total Lower Colorado system at 42% full as of May 20 (compared to 37% full at the same time last year), according to the U.S. Bureau of Reclamation. In Arizona, the Salt River Project is reporting the Salt River system reservoirs at 95% full, the Verde River system at 70% full, and the total reservoir system at 92% full (compared to 99% full a year ago). In New Mexico, the state’s largest reservoir along the Rio Grande is currently at 23% full (59% of average). In the Pacific Northwest, Washington’s Franklin D. Roosevelt Lake is at 87% full (176% of average for the date). In terms of degradations on the map this week, the only noteworthy ones were made in areas of South Florida where areas of Moderate Drought (D1) expanded in response to dry conditions during the past 60-day period with reports of various impacts including burn bans, lake levels dropping at Lake Okeechobee, reduced soil moisture, and some minor impact in the recreation sector due to low surface water levels. Overall, looking at the broader drought situation across the conterminous U.S., the total percentage of drought coverage is at its lowest since 2020.

Forecast

The NWS Weather Prediction Center (WPC) 7-Day Quantitative Precipitation Forecast (QPF) calls for moderate-to-heavy rainfall accumulations ranging from 2 to 5 inches across areas of the eastern portions of the Southern Plains (Oklahoma), South (northeastern Texas, Arkansas, northern Mississippi, Tennessee, Kentucky) and the Midwest (Illinois, Indiana, Ohio) while lesser accumulations (1 to 2.5 inches) are expected in areas of the Upper Midwest, Mid-Atlantic, Northeast, and out West in isolated areas of the Northern Rockies, and eastern plains of Montana. Dry conditions are expected across California, the Great Basin, the Southwest, and the southern extent of the Intermountain West. Likewise, much of the Gulf Coast region is expected to experience relatively dry conditions. The Climate Prediction Center (CPC) 6-10-day Outlook calls for a moderate-to-high probability of above-normal temperatures across much of the South, Southeast, lower Mid-Atlantic, and northern portions of the Northeast. Likewise, above-normal temperatures are expected across most of the western U.S., with the exception of the Far West coastal areas from California to Washington where near-normal temperatures are expected. Conversely, below-normal temperatures are expected in eastern portions of the Central Plains and across much of the Midwest. In terms of precipitation, there is a low-to-moderate probability of above-normal precipitation across the South, Southeast, Mid-Atlantic, and Northeast, while below-normal precipitation is expected across most of the western U.S., Northern Plains, and areas of the Upper Midwest.

Midwest

On this week’s map, there were reductions in areas of drought across portions of Iowa, Missouri, Wisconsin, and Michigan. In Iowa, this week’s heavy rainfall (2 to 6+ inches) combined with improvements in conditions over a broader time scale led to reductions in areas of lingering drought across the state. Similarly, conditions have been trending towards improvement in drought-affected areas of southern Wisconsin and Michigan’s Upper Peninsula. According to the USDA (May 19), statewide pasture and range conditions rated good to excellent are as follows: Minnesota 61%, Iowa 72%, Missouri 71%, Wisconsin 59%, Illinois 85%, Michigan 83%, Indiana 76%, Kentucky 85%, and Ohio 88%. According to the NOAA NCEI’s climatological rankings for the March-April 2024 period, the Upper Midwest Climate Region observed its 10th wettest (+1.57 anomaly) and 12th warmest (+4.8 deg F anomaly) on record.