Tools used in the U.S. Seasonal Drought Outlook (SDO) include the Climate Prediction Center (CPC) temperature and precipitation outlooks for November and November-December-January (NDJ), various short- and medium-range forecasts and models such as the 7-day quantitative precipitation forecast (QPF) totals from the Weather Prediction Center (WPC), the 6-10 day and 8-14 day CPC extended-range forecasts (ERFs), dynamical models at the monthly and seasonal time scale, climatology for NDJ, and initial conditions such as soil moisture. The U.S. Drought Monitor valid on October 17, 2023 was used for initial drought conditions.

The West is beginning the 2023-2024 water year with its lowest drought coverage since 2019. California and much of the Great Basin is drought-free. Based on initial conditions and the lack of a dry signal in the NDJ precipitation tools, no development is expected for these areas. The NDJ outlook favors below-normal precipitation and above-normal temperatures for interior Pacific Northwest, Northern Intermountain West, and Northern Rockies where persistence or development is forecast. To the west of Cascades, the NDJ precipitation outlook forecasts equal chances of below, near, or above-normal precipitation. Based on a wet start to the fall and a wet climatology, improvement/removal are forecast for coastal Oregon and Washington. Although increased chances of below-normal precipitation are forecast for Montana, above-normal precipitation during the past 30 to 90 days makes development unlikely during the next few months. Following the suppressed 2023 Monsoon, broad-scale persistence is favored across much of Arizona and New Mexico where seasonal precipitation tools offer mixed signals. Hurricane Norma is forecast to track northward to the southern Gulf of California during the next week. Heavy precipitation, associated with the remnants of Norma ahead of an amplified trough over the West, could overspread southeastern Arizona and southern/eastern New Mexico. Based on the GEFS and ECMWF ensemble mean, the most likely area to receive drought-improving precipitation would be southeastern New Mexico. Therefore, improvement is forecast for this region.

Forecast confidence for the Western Region is moderate.

For the High Plains region, the most widespread and intense drought remains across parts of Kansas and Nebraska. An amplified 500-hPa trough over the West along with an entrainment of tropical moisture from the East Pacific is expected to bring heavy precipitation to parts of the Central Great Plains during the final week of October. This heavy precipitation along with elevated chances of above-normal precipitation forecast during NDJ favors improvement or removal of drought across Kansas. It should be noted that much of the central to eastern Kansas is long-term which lowers forecast confidence for widespread improvement. Farther to the north, an increasingly dry climatology during the winter and consistent with the NDJ precipitation outlook, persistence is forecast for much of Nebraska and the Dakotas. Forecast confidence is also low for ongoing drought across western Colorado and southwestern Wyoming. Based on the past 30 to 90 days being drier-than-normal and mixed signals in the NDJ precipitation tools, persistence is forecast for these areas.

Forecast confidence for the High Plains is low.

A rapid onset and intensification of drought occurred across the Southern Great Plains, Western Gulf Coast, Lower Mississippi Valley, and Tennessee Valley during the late summer and early fall. Widespread precipitation with locally heavy amounts is expected from the Southern Great Plains east to the Ozarks and Lower Mississippi Valley by late October, as a cold front progresses southeastward. This precipitation along with El Nino composites and the NDJ precipitation outlook favors improvement or removal throughout the Southern Region from late October 2023 through January 2024. It should be noted that although forecast confidence is high for improving drought, hydrological impacts may persist.

Forecast confidence for the South is high.

Short-term drought expanded across Kentucky, Indiana, and Ohio during the late summer and early fall, while recent heavy precipitation resulted in drought improvement throughout the Upper Mississippi Valley. The most widespread, intense drought is focused across Iowa and Missouri. During the final week of October, a strong cold front is forecast to progress through the Midwest and is likely to bring a swath of heavy precipitation to parts of Iowa, Minnesota, Missouri, Illinois, and Wisconsin. Deterministic model solutions continue to differ on the specific area for the heaviest precipitation. Therefore, a consensus between the GEFS and ECMWF ensemble means was used in defining an area that is most likely to receive heavy precipitation and associated drought improvements by the end of October. Beyond this time, the NDJ precipitation outlook depicts equal chances for below, near, or above-normal precipitation for much of the Midwest with slightly elevated probabilities for below-normal precipitation limited to northwest Minnesota and Michigan. Late October and November is a favorable time of year for soil moisture recharge, but drought improvement becomes increasingly less likely by the winter due to a drier climatology. For example, during January, the median percent of annual precipitation is less than 3.5 percent for Iowa, Minnesota, and Wisconsin. Based on the precipitation forecast during late October, the NDJ precipitation tools, and climatology, the highest chance for widespread improvement or removal is across the Eastern Corn Belt, Ohio Valley, and Middle Mississippi Valley. Farther to the north, broad-scale persistence is more likely for northwest Iowa, Minnesota, and northern to central Wisconsin.

Forecast confidence for the Midwest is low.

Drought expanded northward and eastward to the Tennessee Valley and Southern Appalachians during September and early October. CPC’s week-2 (Oct 26-Nov 1) favors above-normal precipitation across the Southeast due to an amplified trough shifting eastward by the end of October. This precipitation may bring minor improvements. During NDJ, forecast confidence is high for drought improvement renewal based on El Nino composites, the NDJ precipitation outlook, and the late fall/early winter is a favorable time of year for soil moisture recharge. The NDJ precipitation outlook depicts large probabilities (more than 50 percent) across the Coastal Plain of the Southeast and part of the Lower Mississippi Valley. Since year-to-date precipitation deficits exceed 12 inches across southwestern Mississippi and southeastern Louisiana, hydrological impacts such as low rivers, streams, ponds and groundwater may persist even if there is soil moisture improvement. Moderate to extreme drought continues in the Ft Myers-Naples area of Florida where year-to-date precipitation deficits exceed 15 inches along the immediate coast. Similar to the Lower Mississippi Valley, long-term hydrological impacts may be slower to improve.

Forecast confidence for the Southeast is high.

Much of the Northeast remains drought-free with only small areas of drought across western parts of New York and West Virginia. Based on the lack of a dry signal on the seasonal time scale and the late fall/early winter is a favorable time of year for soil moisture recharge, drought removal or improvement is forecast for the small existing drought areas of the Northeast.

Forecast confidence is high for the Northeast Region.

Alaska is likely to remain drought-free through the end of January with the NDJ precipitation outlook depicting either equal chances of below, near, or above-normal precipitation or elevated above-normal precipitation probabilities for the North Slope.

Forecast confidence is high for Alaska.

Drought expanded and intensified across Hawaii since August. Based on the NDJ precipitation outlook, persistence or additional development is forecast through January 2024.

Forecast confidence is high for Hawaii.

Tropical Storm Tammy could bring heavy rain to Puerto Rico during the next week. This increased chance of heavy precipitation, a relatively wet climatology through November, and the NMME depicting elevated probabilities for above-normal precipitation during NDJ favors removal for ongoing drought across Puerto Rico.

Forecast confidence is moderate for Puerto Rico.

Tropical Storm Tammy could bring heavy rain to the U.S. Virgin Islands during the next week. This increased chance of heavy precipitation, a relatively wet climatology through November, and the NMME depicting elevated probabilities for above-normal precipitation during NDJ favors drought improvement for St Croix and St Thomas. St John is expected to remain drought-free.

Forecast confidence is moderate for the U.S. Virgin Islands.

Forecaster: Brad Pugh

Next Seasonal Drought Outlook issued: November 16, 2023 at 8:30 AM EST