Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 351 AM EDT Tue Sep 29 2020 Valid 12Z Tue Sep 29 2020 - 12Z Thu Oct 01 2020 ...Heavy showers and thunderstorms with localized flash flooding potential along the East Coast today... ...A pair of cold fronts look to bring below normal temperatures in across much of the central and eastern U.S... ...Fire weather danger in California to persist through mid-week, dry conditions and record heat along the West Coast... A cold front advancing across the eastern U.S. will generate a swath of showers and thunderstorms from the Gulf Coast to New England today. Heavy rainfall rates are likely to occur within the more intense showers and storms thanks to ample Atlantic and Gulf moisture ahead of the front. Some thunderstorms could also be severe, most notably in the eastern Carolinas and southeast Virginia. The Weather Prediction Center has issued a Slight Risk for flash flooding from the Carolinas to the northern Mid-Atlantic with a marginal risk extending from northern Florida to northern New England. The cold front will clear the Mid-Atlantic Tuesday night but slowly push its way into New England Wednesday morning. After a wet morning, drier conditions should return to the Northeast Wednesday afternoon. Farther west, scattered showers are likely to form across the Great Lakes on Wednesday as another frontal system tracks through the region. The aforementioned cold front swinging through the East today is accompanied by a cooler than normal air-mass swinging through the southern Plains and the Mississippi/Ohio Valleys. The below normal temperature regime reaches the East Coast by Wednesday while temperatures rebound to above normal levels in parts of the southern and central Plains. Meanwhile to the north, another cold front is escorting yet another chilly Canadian air-mass across the North Central U.S. mid-week, causing temperatures on Thursday to hover around levels more commonly observed in late October rather than the start of October. The cold front will then head south and east and by Thursday morning is forecast to track over the Mid-South providing a reinforcing shot of below normal temperatures to the Mississippi and Ohio Valleys. The wildfire ravaged portions of the West Coast continue to contend with hotter and drier than normal conditions through mid-week. Some improvement is expected on Tuesday and Wednesday for northern California as the high pressure center weakens and winds gradually subside. However, the Transverse Ranges of southern California remain under an elevated fire weather threat into at least the middle of the week as humidity levels remain quite dry and gusty conditions prevail over the region. Hot temperatures are also be common along the West Coast into Thursday. Heat Advisories have been issued for the Los Angeles and San Diego metro areas and record heat is possible as far north as the Willamette Valley through Wednesday. Mullinax Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php