Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 404 AM EDT Mon Sep 11 2017 Valid 12Z Mon Sep 11 2017 - 12Z Wed Sep 13 2017 ...Hurricane Irma will highly impact the Florida peninsula with dangerous storm surge, destructive wind, and heavy rain... ...Hurricane Irma will slowly weaken to a tropical storm... ...There is a slight risk of severe weather over parts of the Southeast Coast... ...Heavy rain possible over parts of the Southeast/Southern Appalachians/Tennessee Valley... Hurricane Irma will advance roughly northwestward over the Florida peninsula moving into Southwestern Georgia while weakening to a tropical storm by Monday evening. This storm is producing life-threatening storm surge, destructive wind, and heavy rain through to Monday evening. The storm will produce heavy rain and high wind over Florida and the Southeast through Monday evening into Tuesday. For the most current information regarding Irma, please see the National Hurricane Center (www.hurricanes.gov). Meanwhile, an upper-level low off the Southern California Coast will slowly move northward to off the Central California Coast by Tuesday evening. Circulation around the low will pull moisture off the Gulf of California/Pacific that will slowly weak by Tuesday evening. The moisture will aid in developing showers and thunderstorms over parts of Southern California into the Southwest that will expand northward into parts of Northern California into the Great Basin by Monday evening. The showers and thunderstorms will have the greatest areal coverage during the late afternoon into the late evening on Monday and Tuesday. In addition, upper-level energy over the Central Rockies/Central High Plains will be quasi-stationary through Tuesday. The energy will aid in triggering showers and thunderstorms over parts of the Central High Plains/Central Rockies through Tuesday evening. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php