.Pacific storm system to bring heavy snow to the western U.S. along withwindy conditions to the Northwest, central to northern Rockies andadjacent High Plains......Warming trend east of the Rockies with record warmth possible over thecentral U.S. through early week...Relatively tranquil weather over the lower 48 on Saturday will begin tochange on Sunday, beginning in the Pacific Northwest as a fairly strongstorm system approaches from the eastern Pacific and British Columbia. Anupper level disturbance will be preceded by a cold front that will reachWashington late Sunday afternoon. Steady rain will develop for the coastof the Pacific Northwest and lower elevations that are inland whileperiods of heavy snow impact the Cascades to downstream locations of thenorthern Rockies. Snow levels will fall after the cold front moves throughwith a rain/snow mix possible for the Seattle and Portland metropolitanareas Sunday night. Snowfall accumulations of 1 to 3 feet (locally higher)are anticipated for the Cascades and portions of the northern Rockiesthrough Monday night. Heavy snow will begin to impact the central Rockieson Monday. Strong winds will also accompany this storm system with thestrongest winds (gusts over 60 mph) expected for the higher terrain fromWyoming into Montana, however gusty winds of 30 to 50+ mph will also bepossible for some of the adjacent High Plains regions of the U.S. fromNebraska into the Dakotas, extending westward to the foothills of theRockies.Locations east of the Rockies will see low level winds developing fromsouth and west. Westerly flow across the Continental Divide will promotedownslope warming into the Plains, helping bring high temperatures intothe 50s for the northern Plains on Sunday, 60s to 70s for the central tosouthern Plains and 80s for large portions of Texas. By Monday, 80 degreehigh temperatures may spread as far north as Kansas with lower 70s inIowa, about 30-40 degrees above average for late February. This warmthwill likely break some daily high temperature records for portions of thecentral U.S.After a cold start in the eastern U.S. on Sunday, temperatures will climbto near average by mid-day but continue to warm each day through the earlypart of the week. At least through Monday, a lack of moisture will keepmost locations to the east of the Rockies dry, except for some light snowwith a cold frontal passage in New England on Monday.