Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 313 AM EDT Wed Sep 02 2015 Valid 12Z Wed Sep 02 2015 - 12Z Fri Sep 04 2015 ...Temperatures will be 15 to 20 degrees above average over parts of the Northern/Central Plains... A front extending from the Northern Rockies to parts of the Great Basin will move eastward to the Northern Plains then extend roughly southwestward to parts of the Great Basin through Thursday evening. The boundary will aid in producing rain over parts of the Northern Rockies on Wednesday evening expanding into parts of the Northern High Plains by Thursday. Additionally, onshore flow from the Pacific will aid in producing rain over parts of the Pacific Northwest through Thursday. A second front over Eastern Canada will move southward into the Great Lakes/Northeast on Thursday morning that will continue to move southward to the Northern Mid-Atlantic to parts of the Ohio Valley/Great Lakes by Thursday evening. Rain will develop along parts of the front from the Great Lakes to parts of the Northeast on Thursday. Meanwhile, high moisture content air over the Gulf Coast and upper-level impulses will trigger showers and thunderstorms from parts of the Western Gulf Coast eastward to parts of the Southeast through Thursday evening. In addition, upper-level energy over the Ohio Valley will move eastward to off the Southern Mid-Atlantic Coast by Thursday. The energy will aid in producing showers and thunderstorms over parts of the Southern Mid-Atlantic/Central Appalachians on Wednesday evening. Elsewhere, monsoonal moisture and daytime heating will aid in developing showers and thunderstorms over parts of the Southern/Central Rockies and parts of the Great Basin/Southwest on Wednesday and Thursday afternoon into late evening. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php