With a few exceptions, dry weather dominated the contiguous 48 states this past week, particularly in areas already experiencing dryness and drought. Heavy precipitation fell on the orographically-favored areas in the West (specifically, the Sierra Nevada, windward slopes of the Cascades, and much of the coastline from northern California to the Canadian border). Anywhere from 4 to locally 12 inches doused much of these areas. Between 2 and 4 inches fell from central and eastern Illinois eastward across central and northern sections of Indian and Ohio, Michigan, and northwestern Pennsylvania, and similar amounts were more isolated across the higher elevations of the northern Idaho Panhandle, south-central Idaho, western Wyoming and adjacent areas, and a few scattered areas in northern sections of Nevada and Utah. Southern New England and eastern Maine recorded 1 to locally 3 inches of precipitation. Elsewhere - the vast majority of the country from the Great Basin and Southwest eastward across most of the Rockies and Plains, the Mississippi Valley, the Southeast, and the mid-Atlantic region – only a few tenths of an inch of precipitation was recorded, if any.
The next 5 days (November 22-26) look similar to this past week, with most of the contiguous 48 states expecting little if any precipitation. Marginal relief may come to northern Florida and southeastern Georgia, where up to 1.5 inches of precipitation are forecast, and similar amounts should moisten the dry areas of eastern Maine. Moderate precipitation is also possible in far northwestern Montana and adjacent Idaho, but for the rest of the country, including the vast majority of the Nation’s dry areas, little or no precipitation is anticipated. In addition, the dry weather may be exacerbated by well-above-normal temperatures from the Plains westward to the Pacific Coast. Temperatures are expected to average at least 9 degrees F above normal across the western half of the 48 states, reaching as high as 20 to 24 degrees F in central and northern sections of the Rockies and High Plains, as well as the central Intermountain West.
During the 6-10 day period (November 27- December 1), abnormally light precipitation once again looks to dominate the 48 states. Odds favor below-median precipitation in the Southwest, central and southern sections of the Rockies and High Plains, most of the Great Plains and Mississippi Valley from South Dakota and central Minnesota southward to the Gulf Coast, and throughout the Nation east of the Mississippi River, save part of the northwestern Great Lakes Region. Odds favor above-normal precipitation in North Dakota and Montana, which would bring some needed moisture into the broad areas of D2 and D3 covering much of those states. The warmth observed in the central and western U.S. is expected to spread eastward to cover the entire country west of the Appalachians, though the intensity of the abnormal warmth may modify.
The swath from central and northern Ohio westward through central Illinois was one of the few wet areas last week, with 2 to 4 inches of precipitation common. This brought an end to the small area of moderate drought in western Indiana, and eliminated abnormal dryness in northeastern Ohio and part of central Illinois. Farther west, dryness and drought were unchanged in southeastern Iowa.