Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 358 PM EDT Sun Sep 15 2019 Valid 00Z Mon Sep 16 2019 - 00Z Wed Sep 18 2019 ...There is a slight risk of excessive rainfall over parts of the Southwest... ...Temperatures will be 15 to 20 degrees above average over parts of the Northern High Plains... A front extending from the Northern Mid-Atlantic Coast roughly westward to the Great Lakes then northwestward to the Northern High Plains will move southward to the Southeast while draping north of Tropical Storm HUMBERTO over the Atlantic by Tuesday evening. The western parts of the boundary will have a wave of low pressure and associated front that will move from the Northern Rockies/Northern California eastward to the Northern/Central Plains and extending into the Great Basin by Tuesday. Rain associated with the boundary will develop over parts of the Great Lakes into the Northeast on Sunday evening with showers and thunderstorms developing over parts of the Great Lakes into the Western Ohio Valley overnight Sunday. Rain will return on Monday over parts of the Lower Great Lakes into New England as showers and thunderstorms develop over parts of the Ohio Valley. Overnight Monday the precipitation will end until Tuesday evening as showers and thunderstorms develop over the Ohio/Tennessee Valley. Meanwhile, rain will develop over parts of the Pacific Northwest into Northern California on Sunday evening. Overnight Sunday, the rain will move into Central California then into parts of the Great Basin by Monday evening. Rain with embedded thunderstorms will develop over parts of the interior Pacific Northwest on Monday. Overnight Monday, rain will tapper off over the interior Northwest as rain moves into parts of the Northern Rockies on Tuesday. Furthermore, upper-level energy and monsoonal moisture will aid in producing showers and thunderstorms over parts of the Southwest into the Southern Rockies through to Tuesday morning. Heavy rain associated with the thunderstorms will produce mainly localized scattered flash flooding on Sunday evening. In addition, upper-level ridging will aid in producing temperatures that are 15 to 20 degrees above average over parts of the Northern High Plains. Additionally, the upper-level ridging and dry conditions have spawned Red Flag Warnings over much of the Great Basin into parts of California and the Central Rockies. Tropical moisture and an upper-level disturbance will aid in producing showers and thunderstorms along the Central/Western Gulf Coast through Tuesday. The tropical moisture will also aid in producing showers and thunderstorms over Florida through Sunday evening. Tropical Storm Humberto is forecast to move northeastward out over the Atlantic away from the United States. The National Hurricane Center has most up to date information regarding Humberto. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php