Latest Seasonal Assessment - During the past 3 weeks (since mid-January), weather conditions have been quite variable across the lower 48 States. During the first week, mild and wet weather enveloped the Southeast and mid-Atlantic while cold and dry conditions prevailed in the West. By week 2, temperatures moderated in the West as some precipitation fell, especially in Arizona and along coastal Pacific Northwest; however, much colder and drier conditions returned to the eastern half of the Nation. The most recent week saw above normal readings spread across much of the contiguous U.S., with moderate to heavy precipitation falling on the eastern half of the Nation. Early in the period, mild and wet weather prevailed in Alaska while showers have increased in coverage and intensity across much of Hawaii, especially on Kauai and Oahu and the windward sides of the remaining islands.

Year-to-date precipitation (to February 5) has been subnormal in the Far West, central and northern Plains, New England, and along the eastern Gulf and southern Atlantic States. The greatest deficits (3 to 6 inches, locally more than a foot) have accumulated along the Washington, Oregon, and California coasts, in the Cascade and Sierra Nevada Mountains, and from the Florida Panhandle northeastward into the coastal Carolinas. In contrast, surplus precipitation has fallen on the Four Corners Region, southern Plains, most of the Mississippi, Tennessee, and Ohio Valleys, southern half of the Appalachians, and the mid-Atlantic. January 1-February 5 temperatures have averaged below normal in the West, close to normal in the Plains, upper Midwest, and mid-Atlantic, and above normal in the Southeast and New England.

Accordingly, some drought expansion has occurred over the past 3 weeks in Florida, southern Alabama and Georgia, the coastal Carolinas, and parts of Texas. In contrast, improvement was recorded along the northwestern Southeast drought edge and in the mid-Atlantic. Some improvement was also made in parts of the middle and lower Mississippi Valley (from Wisconsin to Arkansas), in the Four Corners region, southern coastal California, and Hawaii. The worst conditions (D3 to D4) have stubbornly persisted in the middle third of the Plains, and in central Georgia.

The updated monthly temperature and precipitation outlooks for February (released Jan. 31) were different from the initial February outlooks released Jan. 17. The latest monthly outlooks kept the odds for above normal precipitation in the northern Plains and upper Midwest, but expanded it southeastward into the Great Lakes region and upper Ohio Valley. In addition, enhanced chances for wetness were now found in the Four Corners Region. With the latter wet probability, odds for subnormal precipitation in the Southwest were now shifted to the central Pacific Coast and along the Gulf Coast. Above-normal February temperatures were expected across the South, from the southern Rockies eastward to the southern Atlantic Coast, with the best chances for subnormal readings in the middle third of the Far West.

As a reminder, the three month precipitation and temperature outlooks (released Jan. 17) favored a much drier pattern across the southern third of the Nation (from central California to the eastern Gulf Coast). This would limit the prospects for further drought improvements during the latter end of the wet season in California, Nevada, and western Arizona, except that the updated monthly precipitation outlook called for enhanced odds of surplus precipitation. Due to the latter forecast, some improvement is possible, mainly from the expected February precipitation, in the Four Corners region. Further east, this also marks a change from recent wet conditions in the southern Plains and western Gulf Coast as drought development and persistence is forecast for Texas by the end of April. Similarly, drought development and persistence is possible in the eastern Gulf Coast States (and from the updated monthly outlook), but less likely further north (equal chances). In the short and medium term, however, very heavy rains are forecast for the central Gulf Coast. As a result, no development was added here, and instead some improvement was expanded southward into southern Alabama and extreme western Florida. Farther north, enhanced probabilities of surplus precipitation across the northern U.S. (from the northern Rockies eastward to the upper Midwest and into the western Corn Belt) increase the odds for drought improvement. Some improvement is possible across the middle Mississippi Valley and the Piedmont, the latter area from wetness forecasted in the short and medium-term period.

Although CPC odds favored subnormal February and FMA rainfall, rainfall intensity and coverage has increased during the past several weeks across Hawaii, especially on Kauai and Oahu and the windward side of the remaining islands, reducing drought across the state. With the lack of an El Niño event (ENSO neutral) and the normal wet season still ongoing, it is difficult to bet against the wet season, especially in the northern and western islands. Accordingly, some improvement was forecast for the leeward sides of Oahu, Molokai, and Lanai, with persistence remaining on the leeward sides of Maui and the Big Island. In Alaska, with odds for above-normal February precipitation, the Koyukuk Basin of north-central Alaska was kept as some improvement in anticipation of increasing its snow pack for late spring melting.

Forecaster: D. Miskus

Next Outlook issued: February 21, 2013 at 8:30 AM EDT

Seasonal Drought Outlook Discussion