Area Forecast Discussion
Issued by NWS Riverton, WY
Issued by NWS Riverton, WY
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833 FXUS65 KRIW 132115 AFDRIW Area Forecast Discussion National Weather Service Riverton WY 315 PM MDT Thu Jun 13 2024 .KEY MESSAGES... - Rivers will continue to run high due to snowmelt, but most have already reached their highest level for the snowmelt season, and will be decreasing over the coming week. - Temperatures continue to run 10 to 15 degrees above seasonal normals through the day Saturday. Most areas will stay dry. - Breezy winds are expected on Saturday combined with temperatures well above normal, leading to elevated fire weather conditions. - Temperatures begin cooling on Sunday, and below average temperatures are expected by Tuesday as the next weather system moves through. && .DISCUSSION... Issued at 250 PM MDT Thu Jun 13 2024 This evening, a shortwave trough moving across the Four Corners region will spread enough mid-level moisture to support isolated showers and thunderstorms for southern and central Wyoming. The main threat with these storms will be brief gusty outflow winds 45 to 55 mph. Showers could (20 % chance) linger well into the day Friday, as the modest supporting lift is slow to exit the region. Gusty winds would again be the main concern with any showers on Friday afternoon. The region remains under the influence of a longwave ridge over the next few days, which brings warm temperatures about 10 to 15 degrees above normal through Saturday. Sustained winds increase slightly on Friday, but will still be relatively light by Wyoming standards. On Saturday the winds become strong and gusty for most locations, and this combined with the heat and dry air in place will lead to elevated fire weather conditions. Thankfully fuels are still relatively moist from spring green- up. Despite the warm temperatures and rapid high elevation snowmelt, most rivers and streams across the region have leveled off, and many are showing signs of slowly falling. The Bear River in southwestern Wyoming is one exception, where peak flows look to occur in the next week or so. The lack of widespread precipitation through the weekend should allow most other rivers to continue to slowly decrease their flow rates. The next large weather system to impact the region will move in Monday into Tuesday. A majority of the lift with this system will be over Montana, leaving Wyoming mostly dry. The northern Wyoming border could (20% chance) see light rainfall during this timeframe. Other areas will stay mostly dry. Temperatures moderate to near normals by the end of next week. && .AVIATION /18Z TAFS THROUGH 18Z FRIDAY/... Issued at 1128 AM MDT Thu Jun 13 2024 VFR conditions are expected at all terminals through the period. There is a slight chance of isolated convection (mainly virga showers) this afternoon; 10% chance at KRKS, KLND, and KRIW; 30% chance at KCPR. A PROB30 group has been included at KCPR, where the best chance for thunderstorms exists. A 10% chance of convective shower activity continues through much of the night at the aforementioned terminals, but no impacts are expected. Winds will remain mostly light (gusts less than 20kts), though a gusty thunderstorm outflow late this afternoon across the southwest or Wind River Basin cannot be ruled out. Any breezy conditions will diminish towards sunset and winds will be light through the night, though will begin to tick back up again Friday morning at several terminals. Please see the Aviation Weather Center and/or CWSU ZDV and ZLC for the latest information on smoke, icing, and turbulence forecasts. && .RIW WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...VandenBoogart AVIATION...Hensley