Accelerated snowmelt from a near-record snowpack due to above normal temperatures produced high and fast flow on drainages in Gunnison County. As a result, flooding compromised and led to the failure of a culvert which led to flooding near Bear Creek.
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 GJT wrote it up.
Accelerated snowmelt from a near-record snowpack due to above normal temperatures produced high and fast flow on drainages in Gunnison County. As a result, flooding compromised and led to the failure of a culvert which led to flooding near Bear Creek.
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 Grand Junction, CO wrote its last area forecast discussion before the first event at Apr 30, 10:30 AM MST, 2 hours 30 minutes earlier.
Area Forecast Discussion National Weather Service Grand Junction CO 1130 AM MDT Sun Apr 30 2023 .SHORT TERM...(Today through Monday) Issued at 406 AM MDT Sun Apr 30 2023 Per previous discussions, the forecast area will be under an amplified high pressure ridge sandwiched between a closed low off the coast of the Pacific Northwest and another over the Great Lakes region. Warm air advection with few clouds will drive afternoon highs to around 10 degrees above normal. However, a weak disturbance in northwest flow may generate isolated thunderstorms over the Elkhead Mountains and Park Range. Diurnal cooling will cause the limited cloud cover to dissipate in the evening. Despite strong radiational cooling during the night, overnight lows are expected to be milder than normal. On Monday the low off the Northwest Coast will sink southward to a position along the northwest California coast by late afternoon. The repositioning of this system will cause the ridge axis to shift eastward while taking on a negative tilt allowing low-level moisture to move northward over the Continental Divide. Continued unseasonable warmth combined with this moderate moisture feed is expected to bring isolated to scattered showers and thunderstorms during the afternoon with the central Colorado mountain ranges favored. Snow levels will largely be above 10,000 feet and accumulating snow should be light and localized. .LONG TERM...(Monday night through Saturday) Issued at 406 AM MDT Sun Apr 30 2023 From Monday night into Tuesday the low along the West Coast moves farther south settling just off the southern California Coast late Tuesday afternoon. Little changes across the forecast area as the prevailing southerly flow continues to deliver moisture over the mountains along the Continental Divide. However, shower and thunderstorm activity increases as moisture deepens over the easternmost ranges of the forecast area on Tuesday. Model solutions indicated a slight downturn in diurnally driven moist convection Wednesday afternoon though the low stays quasi- stationary from Tuesday night into Wednesday. Models appeared to be in better agreement in ejecting a vort lobe northeastward from the southern California low which will pass over the Desert Southwest Wednesday night before pushing over eastern Utah and western Colorado during peak heating on Thursday afternoon. Mid and upper level forcing combines with instability and a stronger surge of moisture from the south to bring more widespread showers and thunderstorms over the mountains and scattered activity over the valleys. Subsidence and drying behind the disturbance suggests decreased activity Thursday night and Friday with the north favored during this period. However, model blends (NBM) seemed tilted in the direction of the Canadian solution which stands as an outlier compared to the GFS and ECMWF solutions which were in very good agreement in suggesting a dry slot will move over the area Friday. However, an uptick in activity is expected Saturday as a second wave moves northeastward across the area. Temperatures are expected to remain around 10 to 15 degrees above normal through midweek before increased clouds and shower activity cools temperatures to levels closer to normal Thursday through Saturday. && .AVIATION...(For the 18Z TAFS through 18Z Monday afternoon) Issued at 1130 AM MDT Sun Apr 30 2023 VFR conditions will prevail over the next 24 hours. Some afternoon breezes could approach 25 mph at some TAF sites but only for a few hours. && .HYDROLOGY... Issued at 406 AM MDT Sun Apr 30 2023 Warming temperatures will continue to accelerate at least the mid elevation snowpack and river forecasts are responding. Many of the tributaries of the upper Yampa Basin will be seeing increasing flows by early next week and likely some of these will exceed bankfull. The Dolores River and associated tributaries will also be on the rise due to releases from a reservoir and the anomalous snowpack in that Basin. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...None. UT...None. && SHORT TERM...NL LONG TERM...NL AVIATION...TGJT HYDROLOGY...15
Hazardous Weather Outlook National Weather Service Grand Junction CO 408 AM MDT Sun Apr 30 2023 COZ001>014-017>023-UTZ022>025-027>029-011015- Lower Yampa River Basin-Central Yampa River Basin- Roan and Tavaputs Plateaus-Elkhead and Park Mountains- Upper Yampa River Basin-Grand Valley-Debeque to Silt Corridor- Central Colorado River Basin-Grand and Battlement Mesas- Gore and Elk Mountains/Central Mountain Valleys- Central Gunnison and Uncompahgre River Basin- West Elk and Sawatch Mountains-Flat Tops- Upper Gunnison River Valley-Uncompahgre Plateau and Dallas Divide- Northwest San Juan Mountains-Southwest San Juan Mountains- Paradox Valley/Lower Dolores River- Four Corners/Upper Dolores River-Animas River Basin- San Juan River Basin-Southeast Utah-Eastern Uinta Mountains- Eastern Uinta Basin-Tavaputs Plateau-Arches/Grand Flat- La Sal and Abajo Mountains-Canyonlands/Natural Bridges- 408 AM MDT Sun Apr 30 2023 This hazardous weather outlook is for eastern Utah and western Colorado. .DAY ONE...Today and Tonight Isolated thunderstorms are possible over the Elkhead Mountains and Park Range this afternoon/evening. .DAYS TWO THROUGH SEVEN...Monday through Saturday Increased thunderstorm activity is expected each afternoon/evening Monday through Wednesday with increased coverage likely Thursday. Meanwhile, warmer than normal temperatures are likely to bring lowland flooding to some areas in western Colorado and eastern Utah during the week ahead. Of particular concern is the Dolores River where releases from the McPhee Dam will add to snow melt in the basin. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed.
The national radar mosaic for the moment the first event began.
1 flood. Local standard time, as filed.
A culvert failed due to excess runoff along Colorado Highway 133 in Bear Creek, or near mile marker 16.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2023Every state in 2023This day in weather historyWarnings in Colorado, April 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: 1086394.