Latest Monthly Assessment -
The January 2014 Drought Outlook is based on initial conditions, short and medium range forecasts, the CPC updated monthly outlooks for temperature and precipitation, and
climatology. During December 2013, the Drought Monitor showed improvement in a few areas across the Rockies and Intermountain West, north-central Texas, the Mississippi
Valley, and the East Coast away from the Gulf of Mexico. In contrast, the depiction deteriorated in the Pacific Northwest west of the Cascades, parts of the central Plains and
Texas Panhandle, southern Texas, a small area near the central Gulf Coast, peninsular Florida, central east-central Alaska, northwestern Hawaii, and a few parts of Hawaii’s Big
Island.
From the upper Mississippi Valley westward to the Pacific Coast, drought is expected to persist or worsen where it exists, with some expansion northward along the West Coast
and into western Utah, the desert Southwest, and northern and western parts of Texas is anticipated. Outside the northern and eastern tiers of this region, the odds favor
subnormal precipitation on all time scales through the month. The odds tilt slightly toward a wetter than normal second week of January in parts of the south-central Great
Plains, including west-central Texas and the Texas Panhandle, but climatological considerations – specifically, that this is a relatively dry time of year, and one during
which surface moisture usually declines – argue against improvement in these regions.
California is one area where, for time scales ranging from a few days to the full month of January, almost all indicators favor below-normal precipitation. Drought persistence
and potential deterioration is forecast here with high confidence.
Above-normal precipitation, potentially including significant snowfall, should lead to the removal of remaining drought areas in the Northeast. Farther south, parts of the
Southeast and Florida are drier than normal, but moderate precipitation should fall on many of these areas during the next couple of weeks, and there is significant uncertainty
in how conditions will unfold across Florida. As a result, no expansion or development of drought is expected in these regions during January.
There are enhanced chances for above-normal precipitation in a swath from southern Texas northeastward through much of Missouri and central Illinois during the second week of
January. In addition, January is a month of neutral or increasing surface moisture climatologically. Drought improvement (removal in areas where the Drought Monitor depicts D1
conditions) is forecast in these areas.
The January outlook calls for enhanced chances of above-normal precipitation throughout Hawaii. Slow drought improvement is expected to continue.
In Alaska, the odds slightly favor below-normal precipitation for the first half of the month in eastern parts of the state, with no discernable tilt of the odds
thereafter. Thus the small area of drought is expected to persist.
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Tools used in the monthly U.S. Drought Outlook (MDO) included the official CPC temperature and precipitation outlooks
for January 2014, various short- and medium-range forecasts and models such as the 6-10 day and 8-14 day forecasts, the NAEFS and ESRL precipitation
outlooks, the soil moisture tools based on the Constructed Analog on Soil (CAS)
moisture, dynamical models (CFSv2, NMME, and IMME), the 384-hour total precipitation forecasts from several runs of the
GFS, the 7-day quantitative precipitation forecast from the NCEP Weather Prediction Center (WPC), climatology, and
initial conditions. ENSO-Neutral conditions are expected to continue through the winter season, the Atlantic and Caribbean hurricane season are over, and few mid-latitude impacts from the current MJO pattern are expected.
In the Northeast, between one and two inches of precipitation (potentially including a heavy snow event) are expected in the areas of drought during the first week
of January, and odds favor above-normal precipitation during the second week of January as well. In addition, even though this is a slightly dry month of the year
climatologically, surface moisture historically increases during the month. Drought is forecast to be removed from the Drought Monitor by the end of the month.
Forecast confidence for the Northeast is high.
Dryness affects scattered areas across the Southeast and Florida, but no areas of full-fledged drought exist as of this writing. Outside of Florida, this is usually a
month of moisture budget recharge, and odds favor light to moderate precipitation in most of the area for the first week or two of the month. The climatology of
Florida is drier than for the rest of the Southeast, and this tends to be a month of moisture depletion rather than recharge in central and southern parts of the
Peninsula. On the whole, climatology, antecedent conditions, and the array of precipitation forecasts do not seem to favor drought development, and none is forecast
(though it is a close call).
Forecast confidence for the Southeast is low in Florida, moderate elsewhere.
From southern Texas northeastward through the middle Mississippi Valley (south and east of Iowa), drought is expected to improve or (in current D1 areas) be removed.
The first few days of the forecast period will be wet in southern Texas. Farther north, the odds favor a wet second week of the month throughout the swath where
improvement is forecast. Otherwise, the short term is dry, and there is no discernable tilt of the odds toward either precipitation extreme later in the month.
Climatologically, this area is transitional, with January typically featuring moisture recharge farther east, and declining moisture farther north and west. Overall,
some improvement seems the most likely outcome, but without much confidence.
Forecast confidence for central and southern Texas, northeastern Texas, northern Missouri, and central Illinois is low.
Across the remainder of the Plains and Mississippi Valley – specifically, from northern and western Texas and eastern New Mexico northward through Nebraska, and
across the drought areas in Iowa, Minnesota, Wisconsin, and adjacent locales – drought is expected to persist, with some expansion in the Texas Panhandle, the Texas
Big Bend, and southeasternmost New Mexico. Most considerations are similar to those farther east in central and southern Texas and the middle Mississippi Valley
(see above); however, [a] the odds for a wet second week of the month are lower; [b] climatologically, January is one of the drier months of the year; and [c]
historically, soil and surface moisture declines during the month. These three factors favor drought persistence and limited expansion, rather than the improvement
forecast farther east.
Forecast confidence for the High Plains, central Great Plains, and upper Mississippi Valley is moderate to high.
For the areas of drought from the Rockies westward to the Pacific Coast, conditions should persist or worsen, and some expansion is possible into areas where [a] D0
currently exists, and [b] precipitation deficits have increased during the last few weeks. These include areas along the central New Mexico/Arizona border, parts of
the desert Southwest, southwestern Utah, and central and western Oregon. Most or all indicators - on all time scales - point toward drier than normal conditions.
Confidence is high.
Forecast confidence for the West is high.
Drier than normal conditions are favored for at least part of January in the small area of Alaskan drought. In the absence of any other compelling information,
persistence is forecast.
Forecast confidence for Alaska is moderate.
The odds favor wetness fairly substantially across Hawaii during January 2014, so slow drought improvement is expected to continue.
Forecast confidence for Hawaii is high.
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