Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 235 PM EDT Sat Jul 12 2014 Valid 00Z Sun Jul 13 2014 - 00Z Tue Jul 15 2014 ...Heavy rain and severe weather possible from the Front Range eastward to the Ohio valley... ...Heat to continue in the Pacific Northwest... ...Much cooler air to plunge southward through the Plains and Great Lakes region tomorrow and Monday... A very active weather pattern is in store for the US over the next few days. A frontal boundary draped across the central Plains as well as through the upper Midwest will move eastward tonight and into Sunday. Showers and thunderstorms along and ahead of the boundary will work through the Great Lakes region with locally heavy rainfall possible. See the latest WPC excessive rainfall discussion (QPFERD) and SPC convective outlook for more information. The west will remain hot with well above normal temperatures continuing in Washington, Oregon, and Idaho -- above 100F -- but the southwest should remain quite summery as well. Along and east of the central Rockies (and including much of Arizona), monsoonal moisture will again help fire off mainly afternoon showers and thunderstorms which could produce heavy rainfall especially over southeastern Colorado. To the north, a Canadian cold front will plunge southward through the Dakotas and Minnesota tonight, bringing in much cooler than normal temperatures. Daytime temperatures will be about 10-20 degrees F cooler than average Sunday and especially Monday. This cold front will become the dominant weather maker for much of the central/eastern states early next week. With a typical hot and humid summertime airmass ahead of a more spring or fall-like airmass behind the front, severe weather will be possible Sunday into Monday from the Ohio valley eastward into the Mid-Atlantic states. Fracasso Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php