Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 404 PM EDT Tue Jul 09 2013 Valid 00Z Wed Jul 10 2013 - 00Z Fri Jul 12 2013 ***Heavy showers and thundershowers expected along and ahead of an advancing cold front from the Midwest to the East Coast*** ***Notably cooler and drier air to filter south from Canada across portions of the Midwest and Great Lakes region*** ***Hot temperatures continue from the Desert Southwest out across the Southern Plains*** Hot weather is again expected to remain over the Desert Southwest and will be expanding northward in coverage across the Intermountain West the next couple of days underneath a larger area of high pressure aloft. Some monsoonal moisture will be trapped underneath this ridge of high pressure and will help foster afternoon and evening showers and thunderstorms through the period. Cooler temperatures associated with the arrival of a cold front though will be moving into the Pacific Northwest Thursday and Friday. This front by the end of the week will also begin to break down some of the heat over the Intermountain West. Farther east across the Central and Eastern U.S., a fairly strong cold front for this time of the year will be moving through Midwest and will be accompanied by numerous showers and thunderstorms. These showers and thunderstorms will extend east into the Ohio Valley, and heavy rainfall is expected to be the result, including some areas of potentially excessive totals. The cold front along with a larger scale trough of low pressure aloft will advance toward the East Coast by Thursday and Friday, and the front should settle well to the south down toward the Gulf Coast states. Numerous showers and thunderstorms will accompany the front through the end of the week. Noticeably cooler and drier air will filter south from Canada in behind the front advancing through the Central and Eastern U.S., and this will ultimately break down the very warm and locally hot weather temperatures seen lately. Orrison Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php