Another week of scant rainfall led to widespread expansion of abnormal dryness (D0) and moderate (D1) to severe (D2) drought across the Midwest, Southeast, and Northeast regions. Extreme (D3) drought was introduced near the confluence of the Mississippi and Ohio Rivers, as well as eastern Ohio and portions of West Virginia. Some expansion of drought and abnormal dryness also occurred across portions of Texas, Oklahoma, and the eastern Plains, while moderate to heavy precipitation brought 1-category improvements to localized areas in western Texas, northward through western Nebraska. Along the Rockies, above-average precipitation yielded fairly widespread 1-category improvements. Above-normal rainfall for the time of year fell across northern California and the Intermountain West, resulting in modest 1-category improvements ahead of the new water year. Enhanced monsoonal moisture was focused across New Mexico and southeastern Arizona, sparking a 1-category reduction from exceptional (D4) drought conditions in the area. 7-day temperature anomalies were above-normal across the Northern Tier and Midwest, exacerbating the rapid onset of impacts, while below-normal temperatures across the east helped to slow the deterioration somewhat. Widespread drought conditions continued for Hawaii, with a 1-category deterioration to extreme (D3) drought on the southern Big Island. Alaska and Puerto Rico remain drought free.
Northeast
Outside of light rainfall overspreading eastern Maryland and the Delmarva Peninsula in association with a coastal low, very little rain fell across the Northeast region during the past week. Temperatures ranging from near to below-normal for the time of year helped to slow the worsening short term impacts, but continued worsening of meteorological indices such as 30 to 90-day SPI values, drying soils, and 28-day streamflow values running far below average warranted widespread deterioration of drought conditions and abnormal dryness. Extreme drought (D3) expanded from central New Hampshire into southern Maine, and new areas of extreme drought were introduced to both central West Virginia and the Northern Panhandle. Drying soils and low streamflow values warranted an expansion of abnormal dryness (D0) across eastern Pennsylvania, southern New York, eastern Massachusetts, and the Allegheny Plateau region of Maryland, while moderate drought (D1) expanded across western Pennsylvania.
Southeast
Another week of robust thunderstorm activity across southern Florida resulted in additional reductions of drought conditions, including a complete removal of severe drought (D2) across the South Florida metro area. Elsewhere across the Southeast region, little rainfall was observed during the past week. This resulted in a fairly widespread expansion of moderate drought (D1) and abnormal dryness (D0) across eastern Alabama, western and southern Georgia, and along the Carolina Piedmont region. Moderate drought expanded to cover most of the uplands of central and northern Virginia, while light rainfall helped preclude any degradations across the southern Appalachians. Due to the rapid nature of this drought onset and temperatures ranging near to below normal, impacts have mostly been observed through meteorological indices, including 30 to 90-day SPI values, and drying soil conditions, while streamflow and groundwater levels remain generally close to average.
South
Spotty convection late in the week brought localized rainfall to portions of Arkansas, northern Mississippi, and Louisiana, but accumulations were generally insufficient to change existing drought conditions. Where rain did not fall, expansion of abnormal dryness (D0) and moderate to severe drought (D1 to D2) occurred across the lower Mississippi Valley and the Tennessee Valley. More widespread rainfall, some locally heavy, overspread western and northern Texas, western Oklahoma, and far southern Texas. Most of this precipitation accumulated outside of existing areas of abnormal dryness or drought, though small 1-category improvements occurred across portions of western Texas, and the rainfall helped prevent further degradations. Drier conditions and seasonably warm temperatures warranted some degradations across central, southern, and eastern Texas, as well as the eastern two thirds of Oklahoma.
Midwest
PlaceholderGenerally wet conditions were observed across the upper Midwest, including Minnesota, Wisconsin, Michigan’s upper peninsula, and northern Iowa. 1-category improvements occurred across northern Minnesota and Michigan, while abnormal dryness (D0) expanded across western Minnesota, which missed out on the rainfall during a week of above-normal temperatures. In contrast, rapidly worsening impacts, persistent subnormal rainfall, and increasingly poor 30 to 90-day SPI values warranted widespread degradations across the remainder of the Great Lakes region and the Ohio Valley. Moderate to severe (D1 to D2) drought expanded to cover much of southern Illinois, Indiana, and Ohio, with a small area of extreme drought (D3) developing in far eastern Ohio. Low humidity and warm temperatures maintained high evapotranspirative rates throughout the week, and in addition to meteorological indices such as SPI showing worsening conditions, groundwater and streamflow values continue to fall. Most of the Ohio Valley remained dry though the week, though a swath of rainfall fell across Indiana, resulting in a small area of improvement that bucked the general trend.
High Plains
Widespread rainfall overspread western Kansas, Nebraska, western South Dakota, and North Dakota during the past week, resulting in modest reductions of abnormal dryness (D0) and moderate drought (D1) across western Kansas and central Nebraska. The highest rainfall totals fell across the Dakotas in regions that are currently drought-free. Drier conditions and warm temperatures prevailed across portions of eastern Kansas and northeastern Nebraska, with declining SPI values warranting some expansion of abnormal dryness (D0). Across Colorado and Wyoming, widespread precipitation fell across the mountainous regions, prompting some drought relief across northwestern Wyoming and much of western Colorado, including reductions in coverage of extreme to severe (D3 to D2) drought conditions.
West
Fairly widespread early season precipitation prompted modest reductions to drought coverage across the Northwest, where widespread severe to extreme (D2 to D3) drought conditions remain entrenched. While much above normal for the time of year, accumulations were fairly modest compared to amounts that can occur during the core weeks of the wet season during the winter. Across the Southwest, robust monsoonal moisture warranted a small reduction in coverage of exceptional drought (D4) across southeastern Arizona and southwestern New Mexico. Further west, improving conditions due to early season precipitation across southern California warranted a reduction of abnormal dryness (D0) across Imperial County. Elsewhere, the drought depiction remained largely unchanged.
Alaska, Hawaii, and Puerto Rico
Heavy precipitation fell across Puerto Rico during the past week, with the highest accumulations occurring west of the areas currently experiencing abnormal dryness (D0). A band of heavy rainfall across northeastern Puerto Rico did warrant a small reduction of D0. Elsewhere, the drought depiction was maintained.
No changes to the depiction of abnormal dryness (D0) across southeastern Alaska were warranted this week. No drought conditions are currently present.
Dry weather during the past week led to worsening agricultural impacts across Hawaii, with reports of degrading field conditions for cattle grazing across the Ka’u region of the Big Island. An area of extreme drought (D3) was introduced across the southern portion of Ka’u in response to these worsening conditions.
Pacific Islands
In the U.S.-Affiliated Pacific Islands, an active weather pattern prevailed during the drought-monitoring period. A developing area of disturbed weather (Invest 90W) contributed to heavy rain across portions of the Marianas, while an active Intertropical Convergence Zone (ITCZ) delivered widespread, locally heavy showers across the Republic of Palau, much of the Federated States of Micronesia (FSM), and portions of the Republic of the Marshall Islands (RMI). In the RMI, lingering abnormal dryness (D0) is limited to northern atolls, including Utirik, Wotje, and Kwajalein. Meanwhile, the FSM remained free of dryness-related concerns, except near the equator, where Kapingamarangi has received less than an inch of rain in four of the last 5 weeks, and has been categorized as being abnormally dry (D0). American Samoa had been trending dry, but significant rain fell at the end of the drought-monitoring period, with 1.56 inches reported at Pago Pago International Airport on September 15-16. Therefore, American Samoa remains free of abnormal dryness.
Virgin Islands
Mostly dry weather in the month since Hurricane Erin passed north of the U.S. Virgin Islands has resulted in short-term dryness (D0) returning across the northern islands of St. Thomas and St. John, while moderate drought (D1) persists on St. Croix. Standardized Precipitation Index (SPI) values, along with increasing depths to water at U.S. Geological Survey wells, are supportive of those designations of dryness and drought. Most vegetation in the territory is not yet exhibiting significant stress, but depth to water at the Adventure 28 well on St. Croix has increased to nearly 19 feet, greatest since November 9, 2024.
Looking Ahead
A frontal system is forecast to help generate widespread precipitation across the Plains states and portions of the Midwest along and west of the Mississippi River during the upcoming week. This rainfall has a potential to bring much needed relief to regions that have experienced rapidly worsening drought conditions. In contrast, lighter rainfall is forecast for the Ohio Valley and East, which, coupled with warmer temperatures, may further exacerbate conditions in areas that have been experiencing rapid drought onset. Another week of heavy rainfall is favored for southern Florida, with drier conditions favored across the Piedmont region of the Southeast. Wet conditions early in the week across the Southwest will give way to a drier pattern overall through the end of the week, though chances of rain will increase by the end of the week across the Northwest.
The Climate Prediction Center’s 6-10 day outlook valid for September 23 – 27 favors above-normal temperatures across the entire contiguous United States, with the highest probabilities extending across the north-central states. Above-normal precipitation is favored across the West Coast and Intermountain West, and across much of Texas and the lower Mississippi Valley and lower Ohio Valley. In contrast, below-normal precipitation is favored along the Rockies and eastward across much of the Great Plains, upper-Midwest, and the western Great Lakes region. Across Alaska, below-normal temperatures are favored for the western half of the state, with above-normal favored for the Panhandle. Near to below-normal precipitation is forecast. For Hawaii, both above-average temperatures and above-average precipitation are favored.
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