Tools used in the Seasonal Drought Outlook (SDO) included the Climate Prediction Center (CPC) temperature and precipitation outlooks for December and December-January-February (DJF), 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 scales, climatology for the DJF season, La Niña composites, and initial conditions such as soil moisture. The U.S. Drought Monitor (USDM), valid on November 15, was used for initial drought conditions.
Drought conditions covered nearly 70 percent of the Western Region as of the November 8th USDM, which is a modest decrease from mid-October as some early season precipitation overspread portions of the Midwest and northern California. Overall, however, there was little change to the drought depiction following a robust summer monsoon season and ahead of the core of the wet season across the Pacific coast states. Following two lackluster winter wet seasons across California due to La Niña conditions, drought conditions are long entrenched across the Southwest, with impacts felt across the soil, groundwater, and reservoir systems. A third consecutive winter of La Niña conditions is strongly favored, which increases the chances for another below-average wet season across the southern half of the Western Region. Therefore, drought persistence is favored for central and southern California and the Southwest. Drought expansion is not anticipated across Arizona and New Mexico due to lingering impacts from the robust monsoon, with above-normal moisture showing up on 6- and 12-month analyses. In contrast, a northward displaced mean storm track favors above-average moisture across the Northwest. Therefore, drought improvements are anticipated for northern California, the Pacific Northwest, and the northern Rockies. The December monthly outlook even favors above-average precipitation across northern Utah, but December precipitation is unlikely to have a substantial impact on the long term drought conditions in this region. Drought persistence is also favored for eastern Montana, where a much drier winter climatology and frozen soils and streams preclude substantive changes to drought impacts until the spring thaw.
Forecast confidence is moderate to high for the Western Region.
Drought coverage has expanded steadily across the Great Plains region since late summer, with just over 76 percent of the region experiencing drought conditions as of November 8th. The broad expansion of drought during the early autumn months was unusual, and occurred due to persistent dry and warm conditions. During early November, a frontal system brought widespread precipitation to eastern Kansas, resulting in some drought relief, while early season moisture across the central Rockies resulted in spotty improvements to western Colorado. More recently, a winter storm brought snow and ice to the Dakotas, which may yield some additional relief as moisture works into the ground. Over the next two weeks, only light precipitation is forecast, yielding little opportunity for any additional late autumn recharge. The DJF season is climatologically dry and cold across the High Plains, with soils and streams gradually freezing over, and any precipitation that does fall resulting in snow cover that does not immediately absorb into the ground. Therefore, despite a seasonal outlook indicating enhanced chances for above-median precipitation across the northern Plains, drought persistence is the most likely outcome across almost the entire High Plains Region. The lone exception is western Wyoming in the central Rockies, where climatological precipitation is considerably higher than across the Plains.
Forecast confidence is high for the High Plains Region.
Persistent warm, dry conditions resulted in widespread drought expansion across the Midwest, with nearly 50 percent of the region experiencing drought, versus close to 10 percent at the beginning of September. Over the last 4 weeks, drought conditions expanded most rapidly across the Ohio River Valley, while a strong frontal system brought widespread precipitation to the parts of the Middle and Upper Mississippi Valley, resulting in some drought reductions across Missouri and Iowa. Further drought reductions during DJF across the Mississippi Valley are less likely, as climatological precipitation decreases substantially and soils and streams freeze over. During typical La Niña winters, a favored storm track tends to set up along the Ohio River Valley. Therefore, the CPC seasonal outlook for DJF favors above-normal precipitation for the Ohio Valley and Great Lakes regions. Based on this outlook, drought improvement is favored for southeastern Missouri, Kentucky, Illinois, Indiana, Ohio, and Michigan.
Forecast confidence is moderate for the Midwest Region.
Extensive drought conditions are also in place across the Southern Region, with just over 70 percent coverage as of November 8th. Rapid drought expansion occurred across eastern Louisiana over the last 30 days, while a strong frontal system brought substantial relief to northeastern Texas and Arkansas. Over the next 7 days, moderate precipitation is forecast to overspread the western and central Gulf Coast area, which may result in modest drought improvements. La Niña winters tend to be drier and warmer than average across much of the south-central CONUS, which favors a gradual expansion of drought conditions across parts of eastern Texas and the Lower Mississippi Valley. Drought development is less likely to occur across western Texas due to increased moisture supply from the robust summer monsoon pattern. Continued improvements during the winter are also favored for northeastern Arkansas due to the favored storm track during La Niña winters.
Forecast confidence is moderate for the Southern Region.
Hot, dry conditions during the first half of autumn resulted in widespread drought degradation across the Southeast Region, with flash drought occurring across the Florida Panhandle, and rapid development across Georgia and the southern Appalachians. Mostly dry conditions are favored over the next 7 days, while the CPC 8-14 day outlook features a slight tilt towards above-normal precipitation. There is a strong signal favoring below-average precipitation and above-average temperatures across the Southeast during La Niña winters, and this signal is borne out in both the CPC December monthly outlooks and the DJF seasonal outlooks. Based on the continued drying initial conditions and the long range forecast, significant expansion of drought is forecast for the Southeast. Uncertainty increases across Northern Alabama due to potential winter storm intrusions. Drought development is possible across South Florida, but the remainder of the Florida Peninsula is favored to remain drought free through the end of February due to abundant moisture in place following Hurricanes Ian and Nicole.
Forecast confidence is moderate to high for the Southeast Region.
The remnants of Hurricane Nicole merged with a frontal system and brought abundant recharging moisture to the Northeast, resulting in continued drought reductions. Spotty drought remains entrenched across parts of the Hudson Valley and southern New England, where groundwater became quite scarce during the summer drought. A second winter storm this week is favored to continue providing good recharge, followed by drier and much colder conditions. The DJF outlook maintains equal chances for below-, near-, and above-normal precipitation across the remaining drought areas of the Northeast; however, a generous winter climatology should provide enough opportunities for continued recharge to further erode the lingering drought. Absent a clear wet signal, however, areas continuing to experience severe drought conditions will likely remain in drought through the end of February.
Forecast confidence is moderate for the Northeast Region.
Increased moisture across Hawaii over the past few weeks has resulted in substantial drought reductions, with drought coverage dropping from more than 90 percent of the islands in late September to 30 percent as of November 8th. La Niña winters tend to be wet across Hawaii, with the core of the wet season commencing in January and February. Based on this outlook, continued drought improvement and removal are forecast.
Forecast confidence is high for Hawaii.
No drought or abnormal dryness is currently in place across Alaska and Puerto Rico, and drought is not favored to develop in either location during the DJF period.
Forecast confidence is high for Alaska and Puerto Rico.
Forecaster: Adam Allgood
Next Seasonal Outlook issued: December 15, 2022 at 8:30 AM EST