Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 329 AM EDT Fri May 8 2015 Valid 12Z Fri May 8 2015 - 12Z Sun May 10 2015 ***Heavy rain and severe storms for the Plains*** ***Scattered showers and storms for the western U.S.*** ***Tropics getting an early start*** Severe thunderstorms and heavy rainfall are expected to make weather headlines over the next couple of days from Texas to the Midwest states. Multiple thunderstorm complexes are forecast to develop in the vicinity of a slow-moving frontal boundary that will be situated across the central Plains and extending over the Upper Midwest. 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., a rather potent upper level low currently over southern California will bring badly needed rain to parts of that state through Friday evening, along with snow for the highest elevations of the Sierra Nevada range. By Saturday, this low is forecast to track eastward across the Intermountain West and result in enough instability for scattered to perhaps widespread showers and storms, with snow for the higher mountain ranges. Temperatures will be above average for most areas east of the Rockies. The nearly stationary area of low pressure off the South Carolina coast has developed enough to become subtropical storm Ana as of late Thursday evening. This is a hybrid between a true tropical storm and a mid-latitude low pressure system. This feature is expected to slowly meander towards the southeast coast this weekend, with periods of heavy rain and gusty winds. The National Hurricane Center and local weather forecast offices have additional information on subtropical storm Ana. Hamrick Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php