Area Forecast Discussion
Issued by NWS Riverton, WY
Issued by NWS Riverton, WY
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509 FXUS65 KRIW 020643 AFDRIW Area Forecast Discussion National Weather Service Riverton WY 1243 AM MDT Tue Jul 2 2024 .KEY MESSAGES... - Continued rain showers and isolated thunderstorms Tuesday, mainly the northern half of the CWA. - Warmer and dryer the remainder of the week and weekend with increasing fire weather risk. && .DISCUSSION... Issued at 1229 AM MDT Tue Jul 2 2024 IR currently depicts the main shortwave pushing across the northern Rockies filling with warmer cloud tops as it loses its diffluence aloft up the longwave pattern towards the upper Great Plains. Radar still shows some light rain showers ongoing for the northern Bighorns and eastern counties that will continue its eastward progression through the morning hours. Otherwise, the backside of the low with a weaker mid level support trough with spark more isolated storms (30-40% coverage) Tuesday afternoon across the northern half of the CWA. Short term models are in fair agreement of redevelopment by 1-2PM from Yellowstone to the northern Bighorn Basin pushing east through the afternoon and early evening. These will diminish towards sunset once the atmosphere losing daytime heating and the instability. As such, severe weather is not expected outside of some gustier outflows through the basin and towards the I-25 corridor of Johnson County. Otherwise, expect the cooler than average temperatures to continue for Tuesday until the longwave trough pushes east and the main finger of the PFJ retreats back to the north. A strong upper level high will being to build from the desert Southwest with increasing convergence aloft toward the end of the week and especially over the weekend. Wednesday will see the highest winds as the gradient as a weaker front pushes through with another shortwave. Isolated higher elevation activity is expected with more of a limited coverage due to lack of low level moisture, and as such, lower humidity values are expected into the longer term forecast as well. Beyond Wednesday, some isolated chances for higher terrain onward into the weekend with mainly dry conditions and a warming trend expected for the entire CWA. 90s back into the fold east of the Divide and 80s to the west as the aforementioned high center to the southwest continues to build and extend through the upper Rockies. No other significant weather is forecasted at this time into the longer term outlook. && .AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/... Issued at 1046 PM MDT Mon Jul 1 2024 Ongoing convection over central Wyoming should diminish between 08Z- 10Z/Tuesday, but may linger until 12Z. Elsewhere, a shortwave taking shape across northwest Wyoming will track east-southeast through the state until around 15Z/Tuesday. An area of showers and a thunderstorm or two will accompany the wave and primarily impact KCOD, KWRL, and then KCPR as it traverses the region. Conditions remain VFR at all terminals despite this convection. Cloud cover decreases from west-to-east late tonight through Tuesday morning. A few weak showers develop over the far north Tuesday afternoon, but it appears isolated and nature and have no terminal impacts in this forecast. West to northwest surface wind increases at the southwest terminals between 16Z-19Z/Tuesday, but it takes a bit longer to mix at KCPR and KRIW. Winds and cloud cover decrease at sunset Tuesday. 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...Lowe AVIATION...Hattings