Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 238 PM EST Fri Feb 01 2019 Valid 00Z Sat Feb 02 2019 - 00Z Mon Feb 04 2019 ...Excessive rain likely over parts of the California Coast... ...Heavy snow likely over the Sierra Nevada... ...Above normal temperatures spread to East Coast by Sunday... Upper-level energy over the Upper Mississippi Valley/Upper Great Lakes will move eastward off the Northeast Coast by late Friday night. The energy is responsible for light snow over parts of the Northern Mid-Atlantic that will end by Friday evening. Cold high pressure over the Great Lakes into the Northeast will slowly move eastward out over the Western Atlantic by Saturday evening. This will allow for southerly flow and warmer temperatures along the East Coast by the end of the weekend. Meanwhile, multiple areas of upper-level energy will flow over the Gulf Coast through Sunday. Moisture from the Gulf of Mexico will flow northward over the Gulf Coast through Sunday. The energy will also aid in producing rain over parts of the Southeast and Lower Mississippi Valley through Monday. A front developing over the Upper Great Lakes on Saturday will move eastward into the Northeast by Saturday evening and off the Northeast Coast by Sunday. On Saturday, snow will develop over parts of the Northeast waning overnight Saturday. A wave of low pressure over the Northern Plains on Friday evening will slowly move northeastward into the Upper Great Lakes by Sunday. Rain will develop over parts of the Middle Mississippi Valley on Saturday that will move into the Upper Great Lakes/Ohio Valley by Sunday morning. By Monday, a wave of low pressure will develop across the Central Plains and a cold front will usher in arctic air to the northern Plains. The result will be a swath of snow across the Northern Plains and Upper Midwest on Monday. In the meantime, a deep upper-level trough over the Eastern Pacific is moving onshore over the West Coast on Friday with an upper-level low moving into California on Saturday into Sunday. The trough will contain a plume of moisture that will move into the California Coast on Saturday that will begin to wane on Sunday. The precipitation across the Pacific Northwest and northern California will move inland to the Northern Intermountain Region by Saturday morning, producing rain and higher elevation snow. The rain will also move into central and southern California by Friday Evening. On Saturday, higher elevation snow will develop over the Sierras. Overnight Saturday, the snow levels will lower as higher elevation snow develop over parts of the Great Basin as rain moves into parts of the Southwest. The precipitation will increase significantly on Saturday bringing heavy rain along the California Coast along with very heavy snowfall for the Sierra Nevada. Flash flooding and debris flows will be a high concern, particularly near burn scar areas in parts of California. An upper-level trough will remain over the western U.S. Sunday and Monday, leading to more mountain snow, coastal rain, and widespread below average temperatures. Snell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php