Heavy Snow spreads into Great Basin, Intermountain West and Rockies.Severe Weather and Excessive Rainfall impacts shift into the SouthernPlains on Friday.Mild temperatures persist across central part of the country throughthis weekend.A powerful low pressure system will spread winter, severe and rain hazardsacross western and central parts of the country. Tonight, heavy rain andsnow impacts will come to an end over California, while tropical andsubtropical moisture converge to spread snow over the Great BasinIntermountain West and Rockies. This snow will continue while the lowpressure system tracks across the Four Corners region on Friday. The stormsystem will reorganize over the Central/Southern High Plains on Fridaywhile it begins to tap moisture and instability from the Gulf of Mexico.This moisture will interact with a prominent jet streak aloft and strongconvergence at the surface along a cold front and dryline. Thiscombination may produce severe thunderstorms across Oklahoma/Texas and theLower Mississippi Valley beginning in the late afternoon on Friday. ASlight Risk (level 2/5) of Severe Thunderstorms is in effect for portionsof South-Central Texas where large hail, tornadoes and strong wind gustswill be possible. The focus for Heavy Rainfall and thunderstorms willshift into the Lower Mississippi Valley and central Gulf Coast on Saturdaywhere the deep redeveloped low pressure system will move into. As aresult, a Slight Risk (level 2/4) of Excessive Rainfall is in effect forportions eastern Texas, southern Arkansas, Louisiana and southernMississippi on Saturday.An omega block ridge over the Central U.S. will support mild temperaturesfrom the Great Plains to the East Coast through this weekend. Portions ofthe Northern/Central Plains into the Upper/Middle Mississippi Valley willexperience low temperatures from the upper 20s to low 50s through earlynext week, which may tie or break existing records. Temperatures in theSouthern Plains will moderate a bit beneath the deepening upper-level lowon Saturday.