A combination of heavy rain and mountain snow melt brought minor flooding along the Wind River. The flooding remained in the low lying areas near the river and caused no property damage or road closure.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS RIW wrote it up.
A combination of heavy rain and mountain snow melt brought minor flooding along the Wind River. The flooding remained in the low lying areas near the river and caused no property damage or road closure.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Riverton, WY wrote its last area forecast discussion before the first event at Jun 20, 3:48 AM MST, 3 hours 12 minutes earlier.
Area Forecast Discussion National Weather Service Riverton WY 448 AM MDT Tue Jun 20 2023 .DISCUSSION...Today through Monday Issued at 249 AM MDT Tue Jun 20 2023 A frontal boundary continues to be stalled across western Wyoming with areas of showers continuing to ride northeastward along it. This front will finally get kicked to the east today and sweep across the area through the day and evening and increase the chance of showers and thunderstorms east of the Divide today. The best jet forcing continues to be across northern Wyoming, so this is where the most numerous storms will most likely form. The Storm Prediction Center does have areas roughly east of Greybull and north of Worland and Kaycee in a marginal risk of severe weather today as well. It does not look like widespread severe weather, but there could be a few strong storms. These storms should end, as the front moves east of the area later tonight. However, the active pattern will continue for a few days as a trough remains to the west, keeping southwest flow over the area with a ridge building across the Desert Southwest. This trough will swing across the area on Wednesday and bring another round of showers and thunderstorms. And, with the northern portions of the area closer to the jet, this will again be the area of the greatest coverage (noticing a trend here). Drier air filtering into southern and western portions of the area should keep coverage to a minimum to none though. Thursday may start out mainly dry, but another shortwave approaching from the southwest will bring another chance of showers and storms. Coverage looks to be more widespread this day, as an upper level low moves toward California, possibly turning low level flow to the east or southeast, bringing in more moisture. The GFS has an interesting solution as well, with a mesolow forming in central Wyoming that may bring a period of moderate to possibly heavy rain Thursday evening. The other models are not as impressed though. The potential is there but pinpointing a small scale feature like this 60 hours out is sketchy at best. Nevertheless, it looks more active across most of the area. On Friday, the upper level low should open up and move northward toward the area. This will, again, lead to a rather active day across much of the area. The wild card is that there will be a dry push of air coming in from the south that could suppress convection. For now, we have tapered the PoPs from north to south as again, with the jet near northern Wyoming, this will be best area for the potential of stronger storms and steadier rain. As we head into the weekend, things should finally begin to become less active. The ridging over the southwest will begin to push northward and the jet will also move northward. This should begin to restrict the chance for convection. The main concern for Saturday will be the potential for some moisture to wrap around the low as it moves into the Northern Plains. The best chance will again be across the north, but less than previous days. On Sunday, ridging will be in place and bring a warmer day with any convection limited to and near the mountains with high elevation heat source generation. Uncertainty really increases early next week. For example, the ECMWF model keeps Wyoming near the top of the ridge in the ring of fire position with daily chances of thunderstorms. Other models really pump the ridge over the Northern Rockies early next week, blocking an upper level low over the Pacific Northwest and keeping convection north and west of the area. This could also lead to the first look at heat across the area, with some areas possibly seeing the first 90 degree highs of the summer. However, confidence for either solution is really a coin flip at this time. We do have high confidence in the active pattern continuing at least through the workweek. && .AVIATION...For the 12Z TAFS through 12Z Wednesday Issued at 447 AM MDT Tue Jun 20 2023 VFR conditions throughout the period for all TAF sites, with MVFR ceilings expected to linger at KJAC. Winds will increase in speed with daytime heating and mixing of the boundary layer to the surface after 18-19Z, gusting up to 25-30 kt again mostly with a westerly component to the directions at all TAF sites. CPR will see the strongest gusts with other locations possible higher with any storm outflows. VCTS carried for all but RKS and CPR, with low confidence for on station outside of COD and LND closer to the higher terrain-induced development. Expect improved skies and diminishing winds after 01- 02Z with sunset and nighttime cooling setting up a weak inversion near the surface lasting through the end of the period. Please see the Aviation Weather Center and/or CWSU ZDV and ZLC for the latest information on smoke, icing, and turbulence forecasts. && .FIRE WEATHER... Issued at 249 AM MDT Tue Jun 20 2023 A cold front will slowly cross the area today and spread showers and thunderstorms to more locations, but again the most numerous storms will be across northern Wyoming. A gusty breeze will develop across southern and portions of central Wyoming, but wind will be less than the previous days. Relative humidity should remain above critical levels. Mixing and smoke dispersal will range from fair to poor across the north to very good to excellent in southern Wyoming. && .RIW WATCHES/WARNINGS/ADVISORIES... NONE. && DISCUSSION...Hattings AVIATION...LaVoie/Lowe FIRE WEATHER...Hattings
Hazardous Weather Outlook National Weather Service Riverton WY 254 AM MDT Tue Jun 20 2023 WYZ001>020-022>030-211300- Yellowstone National Park-Absaroka Mountains-Cody Foothills- North Big Horn Basin-Southwest Big Horn Basin- Southeast Big Horn Basin-Owl Creek and Bridger Mountains- Bighorn Mountains West-Bighorn Mountains Southeast- Northeast Johnson County-Southeast Johnson County- Teton and Gros Ventre Mountains-Jackson Hole- Wind River Mountains West-Wind River Mountains East- Upper Wind River Basin-Wind River Basin-Lander Foothills- Green Mountains and Rattlesnake Range- Natrona County Lower Elevations-Casper Mountain-Star Valley- Salt River and Wyoming Ranges-Upper Green River Basin Foothills- Upper Green River Basin-South Lincoln County- Rock Springs and Green River-Flaming Gorge-East Sweetwater County- 254 AM MDT Tue Jun 20 2023 This Hazardous Weather Outlook is for Western and Central Wyoming. .DAY ONE...Today and tonight. Scattered showers and thunderstorms, especially in the afternoon and evening. Locally stronger storms are possible in northern Wyoming this afternoon and evening. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Wednesday through Saturday...Scattered afternoon and evening showers and thunderstorms, especially northern Wyoming. At this point, Thursday and Friday look to be the most active, with Wednesday and Saturday somewhat less active. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to Standard Operating Procedures.
The national radar mosaic for the moment the first event began.
2 flood. Local standard time, as filed.
Minor flooding occurred along the Wind River near Riverton. The flooding remained in low lying areas near the river and caused no damage.
Minor flooding occurred along the Wind River near Kinnear. No damage or road closures occurred. However, water was close to running over Highway 132 due to a clogged culvert.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2023Every state in 2023This day in weather historyWarnings in Wyoming, June 2023
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1113384, 1113385.