The Ohio Valley, Midwest, South, and East: Two recent storm systems produced more than 4 inches of rain from northeastern Texas to the lower Ohio Valley, eliminating short-term dryness and easing long-term drought. In the East, the most recent storm dropped more than an inch of precipitation in many areas, except in the southern Atlantic States, where only scattered showers fell. Dryness continues to gradually intensify in the southern Atlantic States, with a core severe drought area (D2) centered over western Georgia. The heaviest rain fell north of the core severe drought area (D2) that extends from western Texas through Louisiana.

Due to heavy December rainfall, the area of severe hydrological drought (D2) in the lower Ohio Valley has diminished in size and intensity. According to the USGS, 28 percent of the streamflow gauges in the Ohio Valley were indicating flows in the lowest quarter of historical observations for December 14, down from 83 percent on November 24. As of December 9, however, water shortage warnings remained in effect for 43 of 119 counties in Kentucky. Meanwhile, dry weather (except for light snow showers the last few days) has prevailed recently north and west of a line from northern Missouri to southeastern Wisconsin, resulting in a gradual intensification of abnormal dryness (D0) and first-stage drought (D1). A small area of severe drought (D2) extends southwestward from southwestern Minnesota.

Outlook: During the next 10 days, a series of storm systems will continue to provide generally beneficial, dryness/drought-easing precipitation to the eastern half of the nation, especially from the western Gulf Coast region to the Ohio Valley.

The Plains: Late last week, beneficial rain and snow further eased autumn dryness across southeastern Kansas, much of Oklahoma, and the northern panhandle of Texas. Abnormally dry (D0) conditions persist from western Kansas northward. A core area of first-stage (D1) to severe drought (D2) exists across portions of the middle Missouri Valley, including eastern Nebraska. Although temperatures remain generally above normal, winter wheat has entered dormancy across the northwestern half of the Plains. From now until spring, precipitation that falls on the Plains will protect against winterkill by preventing soil erosion and possibly insulating the crop against possible severe cold outbreaks.

Outlook: Mostly dry weather is forecast during the next 10 days on the central and southern Plains. Some light rain or snow is expected across the northern and eastern Plains as several storm systems traverse the region.

The West: La Nina-driven dryness continues across the Southwest. On the Mongollon Rim of Arizona, Flagstaff recorded an 82nd consecutive day without measurable precipitation on December 15, second only to a 93-day dry spell in April-July 1974. Flagstaff's longest autumn dry spell on record was 77 days in October-December 1903. Precipitation deficits are not yet hydrologically significant, but topsoils are very dry and range/pasture conditions continue to decline. Abnormal dryness (D0) continues to cause agricultural concerns in southern portions of Arizona and New Mexico, and heighten the risk of wildfire activity in southern California. Farther north, the area of abnormal agricultural dryness has been removed due to the continuation of light precipitation in key winter wheat areas.

Outlook: Most dry weather will prevail during the next 10 days in California and southern portions of New Mexico and Arizona. Snow is possible elsewhere in the Four Corners region. A lull in the 8-week wet spell is anticipated in the Pacific Northwest.

Hawaii, Alaska, and Puerto Rico: Heavy rains recently drenched portions of Hawaii, easing drought in those areas affected by long-term moisture deficits. From December 9-12, rainfall reached 10 to 20 inches at several locations on the Big Island, and 3 to 6 inches at numerous locations on Kauai and Oahu. Significant rainfall on Maui, 1 to 4 inches, was limited to windward locations, with only light amounts observed over leeward areas. There are no significant dryness problems in Alaska or Puerto Rico.

Outlook: Hawaii should experience gradual improvement over the next few months as seasonal rains continue.