Tools used in the U.S. Monthly Drought Outlook (MDO) included the Climate Prediction Center (CPC) updated temperature and precipitation outlooks for November, 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), the Week 3-4 outlooks and tools from CPC, dynamical models at the monthly time scale, the 384-hour total precipitation forecasts from several runs of the GFS, and climatology for November. Recent precipitation deficits were also considered. La Nina conditions are present in late October, and are likely (~85%) to continue through the Northern Hemisphere winter, and into spring 2021 (~60% during February-April). The forecaster consensus favors a moderate or even strong La Nina during the peak November-January season, given the latest model guidance and significant atmosphere-ocean coupling already in place.


Northeast: A wide range of drought conditions is evident in the Northeast, from no drought to extreme drought (D3). Moderate to heavy precipitation amounts (0.5-4.0 inches, locally greater) were observed during the past two weeks. With the high water demands of summer (from high heat and high evapotranspiration), and most of the growing season now past, the autumn season typically provides a period of soil moisture recharge. The Week-1 precipitation forecast from WPC predicts up to a half-inch of precipitation throughout most of the Northeast, though 1.0-1.5 inches is possible in eastern Maine and downwind of Lake Ontario. Relative warmth and wetness is predicted by CPC during the Week-2 period. The Week 3-4 precipitation outlook favors above normal precipitation for approximately the northern half of the Northeast region, while the 30-day update has Equal Chances (EC) of below, near, and above normal precipitation. Based on the aforementioned factors, areas of expected improvement and/or drought removal include southern New England, Maine, parts of New York state and western Pennsylvania.


Forecast confidence for the Northeast is moderate.


Southeast: No drought currently exists across the Southeast, thanks to the proximity of stalled fronts and a very active hurricane season. All that remains is an area of lingering dryness (D0) straddling portions of Georgia and South Carolina. This area appears as a relative minimum in rainfall dating back at least 6 months. November climatology favors continuing dryness in this area. The predicted lack of rainfall shown by the various precipitation outlooks at different time scales, and a dry climatology, favor potential drought development in this area in November.


Forecast confidence for the Southeast is moderate to high.


South: Severe to exceptional drought (D2 to D4) exists in western Oklahoma, and western and south-central portions of Texas, with most of the remaining portion of the Southern Region currently drought-free. Percent of Normal Precipitation (PNP) for the last 30-days across Texas and much of Oklahoma varies widely from 5-75 percent of normal, with the lowest values confined primarily to the southern half of Texas. November precipitation climatology favors increasing odds of dryness from east to west across Texas and Oklahoma. Little to no precipitation is expected over the South during the next 7-days, and there is a mix of precipitation anomalies predicted across the region during Week-2. Odds of below normal precipitation are enhanced across the entire Southern Region for both Week 3-4 and the month of November. Therefore, persistence is likely for most areas currently in drought, and some drought development is possible in central Texas. Incidentally, very localized areas of improvement and/or drought removal are indicated along the Oklahoma/Kansas border, based on very recent precipitation, including a significant ice storm.


Forecast confidence for the South is moderate to high.


Midwest: Though much of the Midwestern states are currently free of drought, there are several notable exceptions which include western Iowa (D2 and D3), parts of Minnesota and Missouri (primarily D1), and long swaths of moderate drought (D1) in Illinois and Indiana. During the past two weeks, southern Missouri, and southern portions of both Illinois and Indiana, and Ohio, received anywhere from 2-6 inches of precipitation, locally greater. Other areas, such as the Arrowhead of Minnesota and western Iowa generally received about 0.50-1.25 inches of precipitation. November climatology favors dryness most notably in Iowa and Minnesota, with little to no help from climatology for the vicinity of the Lower Ohio Valley and Michigan. The Week-1 outlook depicts about a half-inch of precipitation for Ohio and Michigan. According to the Week-2, Week 3-4, and updated monthly outlooks, parts of the Middle Mississippi and Ohio Valleys stand the best chance of getting significant precipitation (and therefore improvement and/or drought removal), while other sections of the Region are more likely to receive substantially lower precipitation amounts (which supports drought persistence).


Forecast confidence for the Midwest is low to moderate.


High Plains: Over 98 percent of the High Plains climate region is either in abnormal dryness (D0) or drought (D1-D4), and almost half (47.34 percent) of the region is in severe, extreme, or exceptional drought (D2 to D4). In general, the worst conditions are in the western half of the High Plains. Areas that received at least one inch of precipitation in the last 2 weeks include the southeastern half of Kansas, northern Wyoming, and from southern North Dakota to northern Nebraska. A comparison between October and November climatologies shows an increased likelihood of dryness as autumn progresses. According to WPC, little if any precipitation is forecast in this region during the next 7-days. CPC’s Week-2 precipitation outlook favors a slight tilt toward wetness over the High Plains region. The Week 3-4 and updated 30-day outlooks depict increasing odds for below normal precipitation from north to south. Despite anticipated precipitation during November, persistence is deemed the best bet for nearly all of this Region, except for far southern Kansas as noted earlier in the section on “The South”. Even if adequate precipitation falls in November across the High Plains Region, the benefits of that precipitation are expected to be delayed due to the inability of water to percolate into frozen soil.


Forecast confidence for the High Plains is low to moderate.


West: The vast majority of the West is either in abnormal dryness (D0) or drought (D1-D4). Extreme to exceptional drought (D3 to D4) is widespread across the Four Corners states, Nevada, and from near San Francisco, CA to south-central Washington. In sharp contrast, western Washington, parts of the Northern Rockies, and the southern coast of California are currently drought-free. The widespread coverage and greater intensity of drought across the Southwest is due, in large part, to the lackluster summer monsoon season, which leaves this region particularly vulnerable to the effects of La Nina this cold season, by effectively prolonging and/or intensifying dryness and drought. From October to November, there is a dramatic increase climatologically in the likelihood for above normal precipitation over the Pacific Northwest, northern California, and the Northern Rockies. The Week-1 precipitation outlook favors little to no precipitation for areas of the West already in drought. For the remaining time-scales out to a month in advance, the precipitation outlooks favor significant precipitation only across the Pacific Northwest and Northern Rockies, places that are already mostly free of drought. Therefore, most of the West can expect drought persistence through November, with the likely exceptions of the Pacific Northwest, and to a lesser extent, the Northern Rockies. Some drought development is possible in southern interior California during November, though this is very tricky. Any delay in the onset of the rainy season can have significant impacts on the fisheries industry and the management of rangelands.


Forecast confidence for the West is moderate to high.


Alaska: South-central and northwestern portions of Alaska are currently experiencing abnormally dry conditions, with a localized area of moderate drought (D1) in the vicinity of Kotzebue in the northwest part of the state. The updated 30-day precipitation outlook depicts elevated odds of above normal precipitation in northwestern Alaska, warranting drought removal in November.


Forecast confidence for Alaska is moderate.


Hawaii: The Aloha state continues to experience widespread dryness and drought, with the most intense conditions (D3, extreme drought) in western Molokai, and tiny portions of Maui and the Big Island. With the climatological rainy season and La Nina now in play, the drought outlook for improvement and/or removal should be straightforward. However, the more significant rainfall associated with the rainy season and La Nina typically comes during the winter, not November. Therefore this outlook is considered a toss-up between drought improvement and drought persistence; with only a slight edge given to improvement/removal.


Forecast confidence for Hawaii is moderate.


Puerto Rico: The Commonwealth continues to remain drought free, due in part to the close approach of a tropical cyclone (Isaias) this summer. All that remains are several localized areas of D0. As the climatological rainy season gives way to the dry season in November, it is considered unlikely for significant drought to develop in such a short time..


Forecast confidence for Puerto Rico is moderate.


Forecaster: Anthony Artusa


Next Monthly Outlook issued: November 30, 2020 at 3 PM EST