A Stormy pattern to end February and begin March for the West Coast,inland into the Cascades, Sierra, Great Basin and Northern Rockies.Very heavy snows likely through the Sierra, while lower elevation heavyrains expected from coastal California into the coastal PacificNorthwest..eavy rains expected from the Central Gulf Coast, across the SouthernAppalachians and into the Mid-Atlantic.A  warming trend from the Southern Plains to the East coast, while belowaverage temperatures will persist along the West Coast.A deep upper vortex off the Southwestern Canadian/U.S. Pacific Northwestwill be moving slowly east southeastward over the next few days.  Thiswill support a stormy weather pattern for the West coast, inland throughthe Cascades, Sierra, Great Basin and into the Northern Rockies.  A leadcold front that is moving inland Thursday across the Pacific Northwestwill continue to push eastward into the Northern Rockies and southeastwardthrough northern to central California. This will be followed by a second cold front moving across the same regions later Friday into Saturday.  Thecombination of the two fronts will produce widespread heavy precipitationfrom the coastal Pacific Northwest, south into northern California, theSierra and as far to the south as the central to southern California coastranges.  The most persistent onshore southwesterly flow level flow in thisstormy pattern will be directed into northern to central California.  Veryheavy snows likely through the Sierra over the next two days, with snowtotals of 4 to 6 feet forecast.  While not as great, heavy snowfall alsolikely through the Northern Rockies of Idaho, Montana, Wyoming, throughthe Cascades of Oregon and Washington, the Olympic Range and coast rangesof Washington and Oregon.  Lower elevation heavy rains also likely acrossthe coastal Pacific Northwest, south into the coastal regions ofCalifornia.  Much of California has seen above average precipitation overthe past month, with additional heavy rains increasing the risk ofisolated flash flooding.  At the moment, the greatest likelihood offlooding is across northwestern California and in the foothills of theNorthern Sierra.Wet weather also likely from the Central Gulf Coast, northeastward acrossthe Southern Appalachians and much of the Mid-Atlantic.  Heavy rain isexpected to develop tonight across the Central Gulf coast and spread eastnortheastward in association with fast moving areas of low pressure thatare forecast to move from the northern Gulf of Mexico, northeastward andof the Carolina coast Friday into Saturday.  While widespread moderate toheavy rainfall totals are expected across these regions, the fast movementof the storm and the fact that much of this region has been dry over thepast few weeks, allowing stream flows to fall and soil moisture values todecrease, will be a detriment to widespread flooding issues.   The core of the much above average temperatures areforecast across the Plains into the Upper Mississippi Valley, where hightemperatures are forecast to be 20 to 30+ degrees above average for theend of the week going into the weekend.  A few record high maximumtemperatures possible across the Upper Mississippi Valley Friday andSaturday, with more widespread record highs possible by the end of theweekend across the Upper to Middle Mississippi Valley and across portionsof the Central and Southern Plains.