AdeeptroughintheupperatmosphereisallowingcoldairtosurgesouthwardfromWashingtonandSouthernCaliforniaandeventuallyintotheSouthwest.Snowlevelsaslowas500feetintheBayArea,andaslowas1500feetintheL.A.BasincanbeexpectedasasignificantblossomingofrainandsnowarriveslatetonightintoSaturday.WithstrongwindsaloftaccompanyingtheSaturdaysystem,blizzardconditions,attimes,canbeexpectedovertheSouthernCaliforniahighcountry.