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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 2021-10-26 38.58 61.42 34.88 9.55 0.00 0.00 106
Last Week 2021-10-19 22.97 77.03 45.06 14.05 0.00 0.00 136
Three Months Ago 2021-07-27 28.85 71.15 55.38 29.95 0.00 0.00 156
Start of Calendar Year 2020-12-29 37.84 62.16 36.35 17.59 4.03 0.00 120
Start of Water Year 2021-09-28 24.40 75.60 55.16 18.26 0.00 0.00 149
One Year Ago 2020-10-20 19.20 80.80 47.35 34.98 4.48 0.00 168

DISCUSSION

A series of strong Pacific weather systems moved across the contiguous U.S. (CONUS) during this U.S. Drought Monitor (USDM) week. The first system early in the week spread precipitation across Wyoming to the Upper Mississippi Valley, then left scattered showers over the Northeast before moving off into the Atlantic. The second brought precipitation to northern California and the Pacific Northwest. Its surface low weakened as it crossed the Rockies, but it was re-energized over the Plains and generated precipitation across the central Plains, Great Lakes, and Northeast. The third system slammed into the West Coast near the end of the week. Fed by an atmospheric river of Pacific moisture, its surface low and front left heavy precipitation across California with widespread rain and some high elevation snow from California and the Pacific Northwest to the Great Basin. According to the National Weather Service Weather Prediction Center, as the third low pressure system approached the Pacific Northwest coast, it set a pressure record, testifying to the strength of the system. The October 24th pressure was 942.5 mb, which is a record low pressure for the Pacific Northwest. The end result of these weather systems was above-normal precipitation for the week across much of the West, including the Pacific Northwest, California, Nevada, and the central to northern Rocky Mountains; across eastern portions of the northern and central Plains, the southern Great Lakes, and western and southern portions of the Northeast; and a band of precipitation from southeast Kansas to eastern Kentucky. The precipitation improved short-term conditions, especially in the West, with soil moisture, streamflow, and 1-month to 6-month Standardized Precipitation Index (SPI) indicators sliding into the wet categories. Other drought indicators, such as vegetation-based VHI and VegDRI, were slower to respond. Groundwater, reservoir levels, and longer-term (9-month to 72-month) SPI indicators still indicated very dry long-term drought conditions in the West and northern Plains. The rest of the CONUS was drier than normal, with little to no precipitation falling across much of the Southwest, central and southern Plains, Lower Mississippi Valley to Southeast, northern reaches of the Upper Mississippi Valley, and northern Maine. Weekly temperatures were warmer than normal in the Pacific Northwest to northern and central Rockies, the southern Plains to Gulf of Mexico coast, and along the eastern seaboard. Temperatures averaged cooler than normal in California and the northern Plains to Upper Mississippi Valley. Drought contracted or was reduced in intensity in parts of the West and Midwest, but expanded or intensified in the southern Plains, central High Plains, and Southeast.

Forecast

A frontal low pressure system will complete its trek across the central to eastern CONUS during the next USDM week. For October 26-November 2, up to 3 inches of precipitation is expected from the eastern edge of the Plains to the Mississippi Valley, in parts of the Mid-Atlantic region, and along coastal New England, with 1 to 2 inches widespread in the South, Southeast, and Ohio Valley. Coastal Washington and northwest Oregon could receive 1 to over 5 inches, while the northern Rockies may receive a couple inches of precipitation. Much of the West outside of the Pacific Northwest and northern Rockies, western parts of the Great Plains, and the northern Great Lakes should receive little to no precipitation. Temperatures are expected to average near to above normal. The outlook for November 2-6 shows drier-than-normal weather favored over the Southwest and Upper Mississippi Valley, with wetter-than-normal weather favored from the Pacific Northwest to southern Plains and eastward to the East Coast (except New England). Odds favor colder-than-normal weather for most of the CONUS east of the Rockies. The outlook shows drier-than-normal weather in northeast Alaska and wetter than normal in the south, with warmer-than-normal temperatures for most of the state.

Midwest

Much of the southern and central portions of the Midwest received heavy precipitation, with a band of 2 to locally 4 inches measured from Iowa and northeast Missouri to southern Michigan and northwest Ohio. Areas to the south and north had 0.5 to 2.0 inches, except for a dry spot in southeast Minnesota to central Wisconsin and a dry swath in central Missouri. The northern half of Minnesota received no precipitation. D0 to D2 contracted in Iowa and Illinois, D0-D1 were reduced in Missouri, and D0 was shaved in southwest Minnesota. But D0 and D1 expanded in parts of Wisconsin.