Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 418 AM EDT Sun May 10 2015 Valid 12Z Sun May 10 2015 - 12Z Tue May 12 2015 ***Heavy rain and severe storms for the Plains and Midwest*** ***Late season snow for the Rockies and Dakotas*** ***Tropical storm Ana begins to weaken*** Severe thunderstorms and heavy rainfall are expected to make weather headlines through the beginning of the work week from Texas to the southern Great Lakes. Multiple thunderstorm complexes are forecast to develop in the vicinity of a cold front and strong surface low that will be tracking across the central Plains to Michigan. A dry line over western Texas will also provide enough forcing for thunderstorm development. Localized flash flooding will also be a concern where these thunderstorm complexes become the most persistent. Within the large scale trough over the western U.S., unseasonably cold conditions from the Great Basin to the northern Plains can be expected through Monday as an upper level low passes overhead. Heavy snow is likely for parts of Colorado, Wyoming, and western Nebraska and the Dakotas as deep moisture is advected westward on the northern side of the main surface low. The opposite is true for the eastern half of the country this weekend where temperatures will be above average for early May. The first named tropical storm of the year, Ana, is expected to weaken as it moves over North Carolina on Sunday and gradually become absorbed with the larger scale trough to its west by Monday. There will be periods of heavy rain and gusty winds as the rain bands move inland, but this will mainly be a nuisance type event as far as tropical systems go. The National Hurricane Center and local weather forecast offices have additional information on this storm. Hamrick Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php