Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 PM EDT Sat Jun 11 2016 Valid 00Z Sun Jun 12 2016 - 00Z Tue Jun 14 2016 ...Heat and humidity on the East Coast today will be replaced by a surge of cool air Sunday into Monday... ...Good chance of thunderstorms in the northern Plains through Monday... Summer heat has overspread the mid-Atlantic region today as many places are recording temperatures in the 90's for the first time this year. The heat will be short-lived however, as a cool air mass from eastern Canada and New England is forecast to surge southward through much of the Eastern Seaboard in the next couple of days. Some showers and thunderstorms can be expected with the passage of the cold front. But it appears that many places will not see much rain at all due to a relative lack of available moisture associated with this front. Showers and thunderstorms will persist across the Gulf Coast and Florida along a lingering boundary. This boundary is expected to drift northward and dissipate. A strong ridge anchored over the central U.S. will keep hot and dry conditions over the next few days for the central Plains and portions of the Deep South. Out West, an upper-level low approaching from the Pacific Northwest will trigger the formation of a low pressure system in the northern High Plains near a stationary boundary. Showers and thunderstorms developing ahead of the low are expected to be quite strong over the High Plains today. As the low moves eastward, these thunderstorms will spread across the northern Plains towards the upper Midwest on Monday. Residual instability combined with daytime heating is expected to trigger showers and thunderstorms across portions of the central and southern Rockies from late afternoon into the evening through Monday. Rain associated with the next upper-level trough is expected to move into the coastal Pacific Northwest later on Monday. Kong Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php