Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 210 PM EST Thu Mar 02 2017 Valid 00Z Fri Mar 03 2017 - 00Z Sun Mar 05 2017 ...Heavy snow possible over the Northern Cascades... ...Heavy rain possible over the Pacific Northwest Coast... ...Heavy rain and flash flooding possible across south Texas this weekend... The Pacific Northwest will be in an active wet pattern over the next few days as a Pacific cold front pushes inland and continues eastward into the Intermountain West. Nearly continuous onshore flow will keep rain over the coastal areas of Washington and northwest Oregon-- with snow, likely heavy at times, in the Cascades. Snow will spread eastward toward the Northern Rockies as the front advances inland. Over the Northern Plains/Mid-Mississippi valley a clipper system will slide through bringing light snow over portions of the Northern Plains and Upper Great Lakes this afternoon, to the Great Lakes/Ohio Valley by this evening,into parts of the Lower Great Lakes/Central Appalachians by Friday morning then through parts of the Northern Mid-Atlantic by Friday evening. Lake effect snow will develop by Friday morning for the favored areas downwind of the Great Lakes. Rain and a few thunderstorms are forecast along the Southeast Coast and Florida as a cold front surges southward. This front will weaken by Friday, however a few lingers showers will be possible for south Florida. Further north, a deep low pressure center over Northern Maine will move northeastward into Southeastern Canada during the overnight hours. Rain is expected to transition over to snow this afternoon over Maine. Light snow will taper off over the the Lower Great Lakes/Central Appalachians and the interior Northeast this evening/early Friday morning. Showers and thunderstorms are forecast to develop over Texas and portions of the Gulf of Mexico/Gulf Coast by Friday afternoon and persist into the weekend. South Texas potentially could have significant rainfall totals or higher rainfall rates that may lead to flash flooding. A slight risk for excessive rainfall in effect for this area, please refer to the WPC excessive rainfall outlook for additional information on the threat for flash flooding. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php