Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 515 AM EDT Thu Sep 10 2015 Valid 12Z Thu Sep 10 2015 - 12Z Sat Sep 12 2015 ...Severe thunderstorms possible for portions of the central plains on today... ...Heavy rain possible for portions of north-central Maryland and central Pennsylvania on Saturday... Temperatures across the West are expected to stay near or above seasonal average over the next few days as a ridge of high pressure settles over the area. As the ridge strengthens over the West, the upper-trough and associated cold front will propagate to the east. The trailing end of the cold front will slow its forward movement from the southern plains into the Tennessee valley. As a result, scattered to numerous showers and thunderstorms are expected from the southern plains into the Southeast, Mid-Atlantic, Appalachians, and Northeast today. A wave of low pressure is expected to form near the cold front in the Mid-Atlantic today and track northeastward along the coastline-- this will likely prolong the rain and thunderstorm activity eastern New England into the first part of Friday. Rainfall amounts of 1 to 2 inches are forecast from portions of the northern Mid-Atlantic into eastern New England through early Friday -- and localized flash flooding may be possible, especially near central Maryland/Pennsylvania. A secondary cold front will spill down the Front Range and in push south into the Central Plains/Midwest. Conditions will be favorable over much of the Central Plains today for strong to severe thunderstorms to develop. The Storm Prediction Center has this region highlighted with a slight risk. Rain amounts of 1 to 2 inches possible, primarily over Kansas and Missouri. Isolated higher amounts may be possible in that vicinity. This system will bring much cooler and drier air with it--many locations will see a 5 to 10 degree drop in temperatures in the wake of the front on Friday. Campbell/Ryan Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php