A Pacific low pressure system will move into the state of Wyoming today and will then strengthen over the region this weekend.  There will be plenty of moisture and atmospheric energy that is transferred into the state during this time.  For today, expect thickening clouds, breezy to gusty winds, and developing showers and thunderstorms.  Temperatures will be cooler across western and central Wyoming, with highs in the 50's and 60's.  Meanwhile, unseasonably mild temperatures continue in eastern Wyoming, with highs in the 60's and 70's.  We will then see cloudy to mostly cloudy skies with significantly cooler and near or slightly below normal temperatures on Saturday and Sunday.  Rain, thunderstorms, and mountain snow will be likely statewide.  Heavy rain and mountain snow is also expected.  The first round of heavy precipitation will occur in northwestern and central Wyoming late tonight into Saturday morning.  The next round of heavy precipitation will then arrive in southeastern Wyoming late on Saturday through mid-day on Sunday.  There will also be potential for hail, strong winds, and frequent lightning with any thunderstorm that develops, especially in eastern portions of the state.