Tools used in the U.S. Seasonal Drought Outlook (SDO) included the official Climate Prediction Center (CPC) temperature and precipitation outlooks for February 2016 and February - April (FMA) 2016, various short- and medium-range forecasts and models such as the 7-day quantitative precipitation forecast (QPF) totals from the Weather Prediction Center (WPC), the 6-10 day and 8-14 day CPC extended-range forecasts (ERFs), the NAEFS (North American Ensemble Forecast System) precipitation outlooks, the soil moisture tools based on the Constructed Analog on Soil Moisture (CAS), dynamical models (CFSv2, NMME, IRI, IMME, and ECMWF), the 384-hour total precipitation forecasts from several runs of the GFS, the four-month Palmer drought termination and amelioration probabilities, climatology for the FMA season, and initial conditions. An El Nino (ENSO) Advisory remains in effect, with the January 14, 2016 ENSO Diagnostic Discussion indicating that the strong El Nino is expected to weaken during the spring and transition to ENSO-neutral during the late spring or early summer. Therefore, climate anomalies associated with El Nino played a substantial role in this outlook.

During the past 30 days, above average precipitation fell across northern, central, and far southern California, as well as southern Oregon and parts of the Great Basin. In contrast, below average precipitation was observed across parts of southern California and Arizona. The precipitation resulted in drought improvements across much of Oregon, parts of northern California, the Desert Southwest, and the central Great Basin. As of January 19, snow water equivalent (SWE) values over the Sierra Nevadas generally ranged between 110 and 175 percent of normal; a good start to the water year. Above-normal snowpack levels were also observed across Nevada, Arizona, and southwestern Utah, although below normal SWEs persisted across parts of northern Utah, coincident with lingering areas of moderate to severe drought. The FMA period is a wet time of year across California and the Great Basin, although climatological precipitation drops quickly by the end of March. Climate anomalies associated with El Nino support enhanced precipitation during the late part of the wet season across California. Consequently, CPC's monthly and seasonal guidance both favor above-median precipitation across California, the Great Basin, and the Southwest, with the highest probabilities across southern California. Based on these outlooks, drought improvement or removal is anticipated across southern Oregon, California, the Great Basin, and the Desert Southwest. Additionally, forecast guidance through the next two weeks indicates a very wet pattern across northern California and Oregon. Therefore, removal of severe drought (D2) by the end of the period in this region is likely.
Forecast confidence for California, southern Oregon, the Great Basin, and the Desert Southwest is moderate to high.

Widespread December precipitation resulted in significant drought reduction across the Northwest, with no drought or abnormal dryness (D0) remaining along or west of the Cascades in Washington. The only remaining area of severe drought (D3) is along the front range of the northern Rockies, where SWEs remain below 75 percent of normal in western Montana. El Nino episodes favor abnormally dry conditions across the Northwest, with the strongest signal over the northern Rockies. Wet conditions can push farther north, however, during strong El Nino events. The CPC monthly and seasonal outlooks both favor below-median precipitation across Washington, northern Oregon, northern Idaho, and Montana. In contrast, the WPC 7-day QPF forecast depicts widespread heavy precipitation and high elevation snowfall across the Pacific Northwest, Intermountain West, and northern Rockies. The CPC 8-14 Day Outlook maintains a wet pattern through the Week-2 period as well. Based on recent wetness and the wet forecasts through the end of January, no additional drought development is anticipated west of the Rockies, although drought persistence is indicated in this outlook due to the monthly and seasonal forecasts. Drought development is possible along and east of the front range of the Rockies in Montana.
Forecast confidence for the Northwest and Northern Rockies is moderate.

Across the Plains, only a small drought area remains over south-central North Dakota, while moderate short-term drought conditions developed over southeastern Montana and north-central Wyoming. El Nino related climate anomalies favor below-normal precipitation and above-normal temperatures across the northern Plains, and this is reflected in the CPC monthly and seasonal forecasts. The WPC 7-day QPF forecast indicates widespread light snowfall across the northern Plains, and the CPC 8-14 day outlook forecasts enhanced chances for above-median precipitation. Additionally, there is a well established snowpack across the northern Plains, with SWE values exceeding an inch across northern Montana and North Dakota. Based on the existing snowpack and short range forecasts favoring additional precipitation, no additional drought development is anticipated across the northern Plains; however, persistence is favored for the extant drought areas due to the potential for a dry signal on the seasonal time scale.
Forecast confidence for the Northern Plains is moderate.

Above-normal precipitation during early January alleviated drought conditions across northeastern Pennsylvania and northern New Jersey; however, moderate drought (D1) conditions persisted across southeastern New England. Precipitation forecasts at all time scales during the period favor above-normal precipitation across the mid-Atlantic and Northeast seaboard. Therefore, drought removal remains the favored outcome by the end of April.
Forecast confidence for the Northeast is moderate to high.

El Nino events are associated with suppressed rainfall across Hawaii, due to large scale subsidence north of the enhanced convective envelope near the equator. During the past several weeks, moderate drought (D1) developed across parts of the Big Island and Maui. The CPC monthly and seasonal outlooks for Hawaii favor below-median precipitation and above-median temperatures. Therefore, drought development is anticipated across Hawaii by the end of the period.
Forecast confidence for Hawaii is high.

El Nino conditions favor a wetter than average dry season across Puerto Rico. Forecasts from the CFS favor wet conditions across the Caribbean during Weeks 1 and 2, with a mixed signal during Weeks 3 and 4. The CFS generally favors above-normal precipitation at the seasonal time scale. Based on these dynamical model forecasts, continued drought relief is anticipated across Puerto Rico; however, since it is a relatively dry time of year, drought removal is less likely over the northeastern and southwestern parts of the island, where long-term rainfall deficits are the highest.
Forecast confidence for Puerto Rico is low to moderate.

Forecaster: Adam Allgood

Next Seasonal Drought Outlook issued: February 18, 2016 at 8:30 AM EST