The drought outlook valid from March 15, 2018 through June 30, 2018 is based on initial conditions including soil moisture, current snowpack, and reservoir levels, 7-day precipitation forecasts, extended range (6-10/8-14 day) precipitation and temperature outlooks, the CPC April through June (AMJ) precipitation and temperature outlooks, and climatology.
An increasingly dry time of year broadly favors persistence of ongoing drought across Oregon, California, and the Southwest. Despite below-average snow water content across the Sierra Nevada Mountains, development is expected to be limited due to the 2016-17 wet season, most reservoir levels currently near average, and precipitation during the latter half of March.
Drought is likely to intensify across the southern high Plains during the remainder of March. Based on the AMJ precipitation and temperature outlooks, persistence and development are forecast for much of Oklahoma and Texas.
Prospects for improvement or removal are higher across eastern Kansas and Missouri during the next three months. Recent snowfall and an increasingly wet time of year support improvement or removal of drought across the northern Great Plains by the end of June.
Removal is likely across the small drought areas depicted across the mid-Atlantic, while persistence and a slight expansion of drought are forecast across southern Georgia and parts of South Carolina. Although short-term drought is expected to develop across the Florida Peninsula during the early spring, any drought is likely to be short-lived due to the reliably wet June climatology.
Persistence is forecast for the southern Alaska Panhandle, while abnormal dryness is expected to become moderate drought across parts of southern mainland Alaska and the Kenai Peninsula. Hawaii and Puerto Rico are expected to remain drought-free through the end of June.
Forecast confidence for the West is moderate.
- Drought intensity remained steady or intensified by 1-category throughout the West during the past 30 days. According to preliminary information from the National Centers for Environmental Information (NCEI), California had its 2nd driest winter on record with only a third of its average precipitation from December 2017 through February 2018.
- As of March 13, snow water content across the Sierra Nevada Mountains is running 32 to 40 percent of average for this time of year. These snow water content values are likely to increase during the remainder of March as a series of cold storms enter the West.
- Due to the favorably wet conditions during the 2016-17 water year, many of California reservoirs are near or slightly above normal.
- AMJ is an increasingly dry time of year for California and the driest three-month period for the desert Southwest. Based on climatology and an increased chance of above-normal temperatures and below-normal precipitation during AMJ, persistence is forecast for the ongoing drought areas of the West.
- Development is forecast for parts of California, Nevada, and Oregon where snow water content values remain below-average and March precipitation amounts are not expected to be as high as adjacent areas.
Forecast confidence for the High Plains is moderate.
- Severe to extreme drought continues across southern Colorado with abnormal dryness for northern parts of the state. The highest odds for below-normal precipitation during AMJ are forecast across southwest Colorado.
- Given the below-average snow water content values and increased chances for above-normal temperatures during the spring, persistence and development is the most likely outcome for Colorado.
- Short-term drought continues to worsen for much of Kansas with extreme drought (D3) designated in southwest Kansas. Drought is expected to intensify across southwest Kansas during the next few weeks due to continued dryness and periods of high winds.
- AMJ is an increasingly wet time of year for the central Plains and the most likely area to experience improvement is eastern Kansas.
- A wet February resulted in drought improvement across parts of Montana and eastern South Dakota. Snow water equivalent amounts are currently above 2 inches across most of eastern Montana which bodes well for continued improvement this spring.
- AMJ is an increasingly wet time of year for the northern Great Plains with 40 to 50 percent of their annual precipitation typically occurring during this three-month period.
- The seasonal outlook indicates a slight tilt in the odds for above-normal precipitation for much of eastern Montana and the Dakotas.
- Based largely on the wetter climatology during AMJ and beneficial snowfall recently, improvement or removal is expected across the northern Plains by the end of June.
Forecast confidence for the Southern Region is moderate.
- A sharp gradient of precipitation occurred across Oklahoma since mid-February with the southeast corner of the state receiving as much as 15 inches of rainfall with little or no precipitation across the Panhandle. Therefore, drought was eliminated across southeast Oklahoma while drought remained steady or worsened for the western third of the state.
- Drought conditions vary throughout central and west Texas with extreme drought (D3) ongoing across the Texas Panhandle. A lack of precipitation combined with above-normal temperatures and periods of high winds during the remainder of March is likely to result in worsening drought conditions across the southern high Plains.
- Based on the seasonal outlook favoring below-normal precipitation and above-normal temperatures, drought persistence or development is forecast for western Oklahoma along with western and southern Texas.
Forecast confidence for the Midwest is high.
- Small areas of moderate drought (D1) are designated for parts of the middle Mississippi Valley and northern Minnesota.
- During the past 30 days, much of the Midwest received above-normal precipitation with surplus amounts of more than 4 inches across southern parts of Illinois and Missouri.
- Based on this recent wetness and the increasingly wet time of year during AMJ, removal of ongoing drought is expected.
Forecast confidence for the Southeast is moderate.
- Although the Tennessee Valley and southern Appalachians experienced drought removal during the past month, drought remained or slightly expanded across southern Georgia and the South Carolina Lowcountry.
- Without a wet signal among the tools at any time scale, persistence and continued expansion is most likely across these areas.
- Abnormal dryness continues to expand across the Florida peninsula. Although drought development is anticipated during the next month for this region, it is not expected to persist through the end of June due to the high rainfall amounts that typically occur during that month.
- Small areas of drought are noted in parts of the mid-Atlantic. Removal is forecast for these areas since precipitation averaged at or above-normal during the past 30 days and additional precipitation is expected through the end of March.
Forecast confidence for Alaska is low.
- The southern Alaska Panhandle is designated with short-term drought, while abnormal dryness is posted for southern mainland Alaska including the Kenai peninsula. Impacts for these areas include decreasing reservoir levels and reduced hydroelectric output.
- Without a wet signal among the precipitation tools, persistence is forecast for the southern Alaska Panhandle.
- Development is forecast for parts of southern mainland Alaska and the Kenai Peninsula where abnormal dryness coincides with enhanced odds for below-normal precipitation in the seasonal outlook.
- Hawaii and Puerto Rico are drought-free and none is expected to develop through the end of June.