Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 338 AM EDT Sun Jul 11 2021 Valid 12Z Sun Jul 11 2021 - 12Z Tue Jul 13 2021 ...Heavy rain and potential flooding for parts of the Northeast and the Deep South... ...Heat wave continues for much of the western U.S. through Monday... More unsettled weather returns to the Northeast U.S. over the next couple of days as a slow moving warm front advances northward and leads to widespread moderate to heavy rain with embedded thunderstorms. It appears the heaviest rainfall will likely be across northern Pennsylvania and central portions of upstate New York, where some patchy 2 to 4 inch totals are possible through Tuesday morning. This may lead to some potential flooding and rises on area rivers, especially over river basins that have received above average rainfall over the past several days. Portions of the Deep South are also expected to have bad weather for Sunday and persisting into Monday as deep moisture from the western Gulf of Mexico surges northward ahead of a slow moving frontal boundary. The heaviest rain is anticipated from eastern Texas to northern Alabama, and some 3+ inch rainfall totals are within the realm of possibility where repeated rounds of thunderstorms develop. There is also a Slight Risk of severe storms across some of these same areas on Sunday, with high winds and hail being the main threats with the storms that develop. Excessive heat will continue to make weather headlines across the western third of the nation, especially for California and the lower elevations of Nevada and Arizona. A stubborn upper level high anchored over the Desert Southwest is the primary factor in the ongoing heat wave, and this is expected to slowly erode some going into the beginning of the week. Additional record highs are likely on Sunday, with excessive heat warnings in effect from California to southern Idaho and western Utah. It is also worth noting that overnight lows have also been impressive with this heat wave, with lows failing to drop below the lower 90s for the normally warmer locations of the Desert Southwest. Some localized relief from the extreme heat may arrive in the form of monsoonal showers and storms each day across portions of Arizona and New Mexico. Hamrick Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php