Skip Navigation Links www.nws.noaa.gov 
NOAA logo - Click to go to the NOAA home page National Weather Service   NWS logo - Click to go to the NWS home page
Climate Prediction Center

Outlooks
   Discussion
   Archive
   U.S. Monthly Temp.
      & Prec.

   U.S. Seasonal Temp.
     & Prec.

   Verification

Monitoring and Data
   GIS Data
   U.S. Weekly Drought       Monitor
   Drought
   Soil Moisture

About Us
   Our Mission
   Who We Are

Contact Us
   CPC Information
   CPC Web Team

 
 HOME > Expert Assessments > Drought Information > Seasonal Drought Outlook Summary
 
 
 
United States Seasonal Drought Outlook Graphic - click on image to enlarge
(Click on image to enlarge)
 
PDF Version of Seasonal Drought Outlook Graphic Adobe PDF Reader
 

Latest Seasonal Assessment - Since the previous seasonal outlook release on July 16, unseasonable warmth and subnormal rainfall (e.g. no measureable rain at DFW, TX, since July 9) have expanded short-term drought across parts of the southern Great Plains, lower Mississippi Valley, and parts of the Southeast. After a very wet June and July in the Northeast, rains have also been spotty, slightly increasing abnormal dryness in New England. Similarly, small areas of short-term dryness were found in the upper Midwest. In contrast, improvement occurred in parts of Florida and southern Georgia from heavy rains, and in portions of the Rockies and central and northern Plains from a strong flow of Pacific monsoonal moisture. Record July rains fell on parts of southern California thanks to remnant moisture from Hurricane Delores (e.g. 1.69 inches at San Diego, CA, on July 18-19), but this did not make a dent in the long-term drought. Short-term drought lingered across parts of Alaska, but rains have increased lately. Short-term drought continued on the leeward sides of the Hawaiian Islands as remnant tropical moisture in early August from TS Guillermo kept windward sides drought free. Meanwhile, the drought worsened across the eastern half of Puerto Rico (and much of the Caribbean) as the quiet 2015 Atlantic tropical season continued, although San Juan did receive its greatest daily total (1.82 inches) of the year on Aug. 16. The current El Niño event is one of the strongest on record at this time of the year, and is expected to continue through the winter (90 percent chance) and into the spring (70 percent chance).

The drought outlook valid from August 20, 2015 through the end of November 2015 is based primarily on initial conditions, the CPC seasonal (September-October-November (SON)) and monthly (September) precipitation and temperature outlooks, climatology, and El Niño composites. Although some drought improvement is expected across parts of the Southwest due to increased chances of enhanced September monsoon rainfall and then later from possible enhancement of the autumn subtropical Pacific jet from the strong El Niño, long-term hydrological drought is likely to continue in the Far West. Since SON is a climatologically dry for most of the lower 48 States (although November is wet in the Pacific Northwest), persistence is likely for most of California, except some possible improvement in the southeastern desert. Persistence and intensification of drought (due to increased chances of above-normal temperatures and subnormal precipitation during SON) is expected across the Pacific Northwest and into western Montana.

Due to the very wet spring and early summer across most of the central and eastern U.S., most of the Nation east of the Rockies was drought-free. However, very dry and warm weather during the past 30 days in the southern Plains, lower Mississippi Valley, Great Lakes region, and Northeast have developed or expanded short-term abnormal dryness and drought, especially from the southern Great Plains eastward into the Carolinas. September precipitation odds favor sub-median rainfall along the eastern Gulf and southern Atlantic Coast States, along with above-normal temperatures. Since October and November are climatologically drier than September, and an enhanced sub-tropical jet would most-likely favor areas farther to the west, drought that persists or develops early in the SON period in eastern sections (Georgia-Carolinas-Florida) should linger to the end of November. In contrast, the increased odds for above-median precipitation in western areas (Texas-Louisiana-Arkansas) are due to September monsoonal moisture and a possible El Ni&mtilde;o enhanced sub-tropical jet later, allowing for more and earlier chances of moisture to improve the drought during the SON period. In Florida, a normally wet September combined with sub-median precipitation probabilities (and quiet Atlantic tropical season) favors drought continuation and expansion. In the Northeast, dryness is favored during SON based upon strong El Niño analogs, hence drought persistence and expansion was made.

Drought removal is expected across Alaska as September is climatologically wet and the monthly precipitation outlook favors above-median totals (as does SON along the southern coast). The areas of moderate drought along the leeward sides of the Hawaiian Islands is forecast to persist as above-median September rainfall should be limited to the windward, east-facing slopes. This should eliminate some small D1 areas on Maui's and Kauai's windward sides. Concerns for expansion of Hawaiian drought during the winter and spring months are possible as strong El Ni&mtilde;os tend to bring reduced rainfall. In Puerto Rico, suppression of summer convection has continued, including minimal tropical cyclone activity across the Caribbean region which is typical during El Niño summers. Therefore, barring any unforeseen tropical system(s), drought persistence with some expansion is the most likely outcome across Puerto Rico.

Forecaster: D. Miskus

Next Seasonal Drought Outlook issued: September 17, 2015 at 8:30 AM EDT

Seasonal Drought Outlook Discussion


NOAA/ National Weather Service
National Centers for Environmental Prediction
Climate Prediction Center
5830 University Research Court
College Park, Maryland 20740
Page Author: Climate Prediction Center Internet Team
Page last modified: August 20, 2015
Disclaimer
Information Quality
Credits
Glossary
Privacy Policy
Freedom of Information Act (FOIA)
About Us
Career Opportunities