Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 337 AM EDT Mon Sep 15 2014 Valid 12Z Mon Sep 15 2014 - 12Z Wed Sep 17 2014 ...Temperatures will be 10 degrees below average from parts of the Northern/Central Plains to the Great Lakes... A developing front over the Central Plains will move southward to the Southern Plain while extending eastward to the Southeast Coast by Tuesday evening. The boundary will trigger showers and thunderstorms over parts of the Central Plain/Middle Mississippi Valley on Monday moving into parts of the Ohio Valley by Monday evening. Showers and thunderstorms will ignite again over parts of the Southern Plains into the Southern Rockies Monday night into Tuesday morning. In addition, upper-level energy over the Upper Mississippi Valley will move eastward to off the Northeast Coast by Tuesday. The energy will produce rain over parts of the Upper Mississippi Valley/Upper Great Lakes on Monday moving eastward to the Northeast/Mid-Atlantic Coast by Tuesday morning. Meanwhile, an old front along the Southeast Coast/Eastern Gulf Coast will aid in producing showers and thunderstorms over parts of the Southeast and the Gulf Coast through Tuesday. Elsewhere, monsoonal moisture and additional moisture surging northward out of the Gulf of California will aid in producing shower and thunderstorms over parts of the Southwest Monday afternoon into Tuesday evening. Additionally, high pressure over the Northern Plains will move southeastward to the Ohio Valley by Tuesday evening. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php