Area Forecast Discussion
Issued by NWS Riverton, WY
Issued by NWS Riverton, WY
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625 FXUS65 KRIW 111857 AFDRIW Area Forecast Discussion National Weather Service Riverton WY 1257 PM MDT Sat May 11 2024 .KEY MESSAGES... - Generally quiet weather, with above normal temperatures expected through the week, with weak ridging in place. - A series of weak shortwave will bring afternoon shower chances (15 to 25%) to the higher terrain through the weekend. - Stronger shortwaves early and mid-week will promote more widespread shower and thunderstorm chances. && .DISCUSSION... Issued at 1256 PM MDT Sat May 11 2024 Our weather remains quiet, which means that the mostly clear skies that we had all night will continue through today. The clear skies last night allowed us to view Nature`s light show, and what a show it was. If you didn`t catch the aurora last night, another night of mostly clear skies will allow you another chance tonight. Weak ridging will keep mostly quiet weather and warm temperatures across the region through the weekend and even through much of next week. Temperatures today will be around 5 degrees above normal with widespread 70s east of the Divide and upper 60s to near 70 across lower elevations west of the Divide. Temperatures will be another few degrees warmer Tomorrow and even warmer yet on Monday. Highs on Monday will be close to 15 degrees above seasonal normals across much of the region. A slight cool down back to near normal temps looks to occur mid-week, but temps quickly warm back up late in the week. Flow remains weak, so winds will be light through the week as well. Now, it won`t be perfectly quiet weather, as there are a series of shortwaves that will pass through the region, one per afternoon through Tuesday. Today`s will be limited to a few very isolated showers across thigh northern mountain peaks. Perhaps up to a 20% chance of showers for a brief time this afternoon in the highest peaks of the Bighorns and Absarokas. Tomorrow will be a very similar situation, however, PoPs are more in the 30 to 40% range for the Bighorns. Could even see some showers develop off the Bighorns and slide across Johnson County (20% chance). Overall though, no real impacts. Monday`s shortwave will be a bit more potent, and showers, along with thunderstorms, look to be more widespread across areas east of the Divide, particularly the Bighorn Basin and Johnson and Natrona Counties. Tuesday`s will be even more potent, with showers and thunderstorms looking to be widespread across the region, especially east of the Divide, with showers continuing through the day Wednesday. Thursday and Friday look to be quieter on the precipitation front, though westerly winds do look to increase slightly as the gradient tightens with a messy cluster of low pressure systems to the north over Canada. Details with any of these shortwaves (particularly the more potent ones Monday and Tuesday) are not able to be resolved yet, so strong thunderstorm chances, precipitation amounts, and impacts are still uncertain at this time. && .AVIATION /18Z TAFS THROUGH 18Z SUNDAY/... Issued at 1000 AM MDT Sat May 11 2024 VFR conditions, with SKC skies, and light winds will begin the TAF period. High clouds will stream over the area from the north through the afternoon, as CU develops over southern portions of the forecast area, as well as the Bighorn Mountains. There remains a 10% chance of isolated showers and thunderstorms for these areas and have left VCSH/VCTS mentions out of the forecast, as they are not expected to pose any direct impact to any terminal. The one exception could by gusty outflow winds hitting KBPI/KPNA late this afternoon toward 00Z. Winds will remain light overnight, with mostly clear skies. 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...Hensley AVIATION...LaVoie