Area Forecast Discussion
Issued by NWS Riverton, WY
Issued by NWS Riverton, WY
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000 FXUS65 KRIW 160417 AFDRIW Area Forecast Discussion National Weather Service Riverton WY 1017 PM MDT Wed May 15 2024 .KEY MESSAGES... - Isolated mountain showers going forward each afternoon and evening. - Elevated fire weather Friday and over the weekend. - Next system will come in Sunday night into early next week. && .DISCUSSION... Issued at 1216 PM MDT Wed May 15 2024 Current IR depicts the shortwave that affected the CWA pushing southeast into the high plains. Improved skies and upper level ridging has begun to extend across the upper Rockies. The high is centered off the west coast continuing to build with increasing convergence aloft. Being a more zonal flow across the CWA with the main finger of the PFJ well to the north into Canada. More of a westerly flow induced rain showers this afternoon across the Divide and points west with no impacts expected. Less wind and warmer temperatures will continue through the weekend with a series of weak shortwaves skimming the northern CWA. Weak showers and a couple isolated storms possible for the higher terrain but overall quieter weather pattern. Friday and over the weekend will see the warmest temperatures along with increasing southwest winds ahead of the next system. Wind gusts will exceed 30 mph in the wind prone areas that will increase fire weather risk to elevated for these areas as humidity drops due to these increasing temperatures. However, with green-up still ongoing, minor impacts expected but keeping an eye out for the situation at hand. Sunday night will see a deepening trough over the Pacific northwest dropping down from the GOA. Increasing divergence aloft will allow it do deepen quite a bit as it extends southward through the Sierra Nevadas. Impacts for western zones will start as early as Monday morning with mountain snow and valley rain before spreading eastward later in the day. Longer term models indicate the trough to close off and spin a series of shortwaves through the upper Rockies through much of next work week before kicking off to the east by next Friday and into the following weekend. Based upon this, it seems to be due to the jet cutting off to the north pinching off the PVA into the low as it fills and gets embedded into the southern portions of the jet stream. Time will tell, but this looks to be the next system of interest. With it, will come more seasonable to just under average temperatures and wetter conditions to come. Stay tuned for updates in the coming days as specifics are for sure uncertain at this time. && .AVIATION /06Z TAFS THROUGH 06Z FRIDAY/... Issued at 1016 PM MDT Wed May 15 2024 FEW/SCT100-200 clouds will hang around some terminals to start the period, mainly across the northern half of Wyoming. Prevailing VFR conditions will remain in place through the majority of the TAF period. Winds remain light through the overnight and morning hours on Thursday. Wind will begin to increase at most terminals by the early afternoon hours Thursday, with gusts around 15-20 knots. Wind gusts may near 25 knots, especially near KCOD and KCPR, during the mid-late afternoon. Winds decrease by sunset becoming light and mainly westerly for the overnight hours. SKC conditions are expected to develop by the end of the TAF period across most terminals. Please see the Aviation Weather Center and/or CWSU ZDV and ZLC for the latest information on icing and turbulence forecasts. && .RIW WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Lowe AVIATION...Dziewaltowski/LaVoie