Tools used in the U.S. Seasonal Drought Outlook (SDO) included the official Climate Prediction Center (CPC) temperature and precipitation outlooks
for February 2014, the long lead forecast for February - April 2014, various short- and medium-range forecasts and models such as the 5-day and 7-day precipitation totals
from the Weather Prediction Center, 6-10 day and 8-14 day CPC forecasts, the NAEFS 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 four-month Palmer drought termination and amelioration probabilities, climatology, and initial conditions. ENSO conditions continue to be and are
forecast to remain neutral.
A persistent, upper-level ridge across the east Pacific resulted in an unusually dry start to the wet season for the West Coast. According to AHPS, 90-day
precipitation deficits exceed 16 inches across coastal areas of northern California and the Pacific Northwest along with the Sierras. Winter is a critical time to
build an adequate snowpack for water resources across these areas. The Sierra Nevada Mountains have a near historically low snowpack for this time of year. According
to the Western Regional Climate Center, river basin snow water content values as of January 13 are running at the lowest 5th percentile across the Sierras and
southern Cascades. Model guidance on January 15 indicates that a highly amplified ridge will remain anchored along the West Coast during the next two weeks, which
strongly favors little or no precipitation. Due to the extremely dry initial conditions and likely continuation of dry weather during the remainder of January,
persistence or intensification of drought is forecast for the Pacific Northwest and California. Even if a pattern change with much-needed precipitation occurs along
the West Coast during February, precipitation deficits and an inadequate snowpack are anticipated to persist throughout the remainder of this outlook period. Forecast
confidence is lower across the Pacific Northwest than California where the CPC seasonal outlook calls for enhanced odds of below-median precipitation.
Forecast confidence ranges from high across California to moderate across the Pacific Northwest.
Forecast reasoning for the ongoing drought areas of the West and expansion of drought across the Southwest is similar to the West Coast addressed in the previous
paragraph. Although 90-day precipitation deficits are not as extreme across the interior West, river basin snow water content values are running below-average across
most of Idaho, Nevada, Utah, and the Southwest. The persistent ridge along the West Coast is likely to result in little or no precipitation during the next two weeks
across these areas. The CPC seasonal precipitation outlook calls for enhanced odds for below-median precipitation across the Southwest with equal chances to the north
across the northern Great Basin. A lack of a wet signal among the tools and initially dry conditions support persistence or development of drought across the interior
West and Southwest. In addition, enhanced odds for above normal temperatures forecast during FMA raises the chances for an early season snow melt.
Forecast confidence for the interior West and Southwest is moderate.
The CPC seasonal outlook calls for equal chances of above, near, or below-median precipitation across the central and southern Great Plains during FMA. The upstream
ridge along the West Coast is likely to maintain a dry pattern across the central and southern Great Plains at least through the next ten days. Persistence is
forecast across the central and southern Great Plains, but forecast confidence is tempered due to weak signals among the seasonal precipitation tools and increasing
wet climatology during April.
Forecast confidence for the central and southern Great Plains is low.
Persistence is the most likely category across the ongoing drought areas of Texas but confidence is low due to weak signals among the seasonal precipitation tools.
30-day precipitation deficits support a small expansion of drought across west and southeast Texas. Also, the CPC February outlook calls for enhanced odds for
below-median precipitation across southeast Texas. Development is not forecast across south Texas due to 30-day precipitation surpluses for this area. Meanwhile,
development across southern Louisiana is based on increasing short-term precipitation deficits along with increased chances of below-median precipitation in CPC’s
monthly and seasonal precipitation outlooks.
Forecast confidence for Texas and southern Louisiana is low.
Drought coverage and intensity remained steady during the past month across the Midwest which is typical for winter as soil moisture recharge is limited. Since
precipitation begins to increase during the early spring across southeast Iowa, Missouri, and Illinois, drought removal or improvement (where drought levels are D2)
are forecast for these areas. Climatology is slightly drier to the north across Minnesota and Wisconsin where persistence is forecast.
Forecast confidence for the Midwest is low.
Long-term moderate drought conditions continue across small parts of the Northeast. Precipitation averaged near to above-normal during the past 60 days across the
Northeast with only long-term drought indicators supporting the current drought status. Since the drought level is moderate and the tools offer no dry signal, drought
is expected to end before the end of April across the Northeast.
Forecast confidence for the Northeast is high.
A small area of moderate drought continues in east-central Alaska. Since the 6-10 and 8-14 day outlooks favor above-median precipitation for Alaska and equal chances
are forecast by the CPC seasonal outlook, drought removal is most likely.
Forecast confidence for Alaska is high.
Since the CPC February precipitation outlook favors above-median precipitation, improvement or removal of drought is forecast across the Hawaiian Islands. It should
be noted that precipitation typically decreases later during this outlook period.
Forecast confidence for Hawaii is high.
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