Berthoud Pass was closed for hours south of Winter Park due to a snow slide that was blocking the roadway. S.
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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 BOU wrote it up.
Berthoud Pass was closed for hours south of Winter Park due to a snow slide that was blocking the roadway. U.S. 40 was closed between Henderson Mine Road and Robins Roost from about 1:20 p.m. until just after 5 p.m.
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 Denver/Boulder, CO wrote its last area forecast discussion before the first event at Apr 11, 10:25 AM MST, 2 hours 55 minutes earlier.
Area Forecast Discussion National Weather Service Denver/Boulder CO 1125 AM MDT Tue Apr 11 2023 .UPDATE... Issued at 1124 AM MDT Tue Apr 11 2023 Upper ridging in place over the CWA at this time. There are just a few high clouds around. At the surface, the winds across the CWA are pretty weak. Temperatures are well into the 70s across the plains right now, with 60s in the foothills. Denver's DIA will likely have a new record daily high temperature shortly with the current reading at 79 degrees F and the record for the day sitting at 80 degrees F. Will make some cosmetic changes to the temperature, sky and wind GFE grids based on current conditions and real data. && .SHORT TERM...(Today and tonight) Issued at 248 AM MDT Tue Apr 11 2023 An upper level ridge will remain over the area today with dry conditions and well above normal temperatures. 850-700 mb temps would support highs in the lower to mid 80s across nern CO. Record high at Denver is 80 and can't imagine that won't be broken this aftn. In addition, will likely see other locations with record highs today as well. For tonight it will remain dry with mild lows overnight across the plains. .LONG TERM...(Wednesday through Monday) Issued at 248 AM MDT Tue Apr 11 2023 Another record warm day expected on Wednesday as an increasing southwesterly flow aloft develops over the region ahead of an approaching trough over the Pacific Northwest. The record high temperature of 79 in Denver on the 12th, will be easily broken for Wednesday with the high around 84. There will be a chance of some weak showers in the high country by Wednesday afternoon. Inverted V type profiles for Denver with minimal CAPES but stronger DCAPE values around 1400 j/kg, which could result in virga and gusty outflow winds to 50 mph across the plains. Gusty southerly winds to 35 mph possible especially along the Palmer Divide Wednesday afternoon. On Thursday, the flow aloft increases further with even stronger winds expected across the plains in the afternoon. Increasing mid/upper level moisture from the west, will shave a few degrees off the expected high temperatures, but it will still be close to 15 degrees above the normal. Reference the fire weather section below for additional details for Wednesday and Thursday. A cold front will push across the region Thursday night, with the trough moving across the northern and central Rockies Friday into Friday night. High temperatures will 20-25 degrees cooler by Friday with a showers likely across much of the region. There will be weak instability in the afternoon over the elevated terrain, enough for isolated thunderstorm coverage. Continued cool but drier weather is forecast for Saturday, with a more subsident northwesterly flow aloft over CO. Outside of some scattered snow showers in the mountains northwest facing slopes it will be dry. A ridge will build back over the region starting on Sunday with a trend of dry and warm weather expected through the early part of next week. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) Issued at 1124 AM MDT Tue Apr 11 2023 Models keep normal diurnal wind patterns going at DIA today and tonight. Wind speeds will be on the low side. There will not be any ceiling issues. && .FIRE WEATHER... Issued at 248 AM MDT Tue Apr 11 2023 Elevated fire conditions will be in place this afternoon across portions of the plains due to warm temperatures and low humidity. However, winds should stay below Red Flag criteria in most locations. Critical fire weather conditions will occur Wednesday mainly along the southern foothills, Palmer Divide, and adjacent plains due to low relative humidity as low as 10 percent and gusty southwest winds producing gusts up to 35 mph. These conditions are expected to continue until early Wednesday evening. Thursday, winds will be stronger, with another period of elevated to critical fire weather conditions in the afternoon. No fire weather watch yet, but may again be needed at some point for Thursday afternoon. Cooler temperatures and a good chance of showers will allow for some relief for Friday. && .BOU WATCHES/WARNINGS/ADVISORIES... Fire Weather Watch from Wednesday afternoon through Wednesday evening for COZ216-241-246-247. && UPDATE.........RJK SHORT TERM.....RPK LONG TERM......Cooper AVIATION.......RJK FIRE WEATHER...Cooper
Hazardous Weather Outlook National Weather Service Denver/Boulder CO 1022 AM MDT Tue Apr 11 2023 COZ030>051-121630- Jackson County Below 9000 Feet- West Jackson and West Grand Counties Above 9000 Feet- Grand and Summit Counties Below 9000 Feet- South and East Jackson/Larimer/North and Northeast Grand/ Northwest Boulder Counties Above 9000 Feet- South and Southeast Grand/West Central and Southwest Boulder/ Gilpin/Clear Creek/Summit/North and West Park Counties Above 9000 Feet-Larimer and Boulder Counties Between 6000 and 9000 Feet- Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear Creek/Northeast Park Counties Below 9000 Feet- Central and Southeast Park County- Larimer County Below 6000 Feet/Northwest Weld County- Boulder And Jefferson Counties Below 6000 Feet/West Broomfield County- North Douglas County Below 6000 Feet/Denver/West Adams and Arapahoe Counties/East Broomfield County- Elbert/Central and East Douglas Counties Above 6000 Feet- Northeast Weld County-Central and South Weld County-Morgan County- Central and East Adams and Arapahoe Counties- North and Northeast Elbert County Below 6000 Feet/North Lincoln County- Southeast Elbert County Below 6000 Feet/South Lincoln County- Logan County-Washington County-Sedgwick County-Phillips County- 1022 AM MDT Tue Apr 11 2023 This hazardous weather outlook is for northeast and north central Colorado. .DAY ONE...Today and Tonight Elevated fire weather conditions will be in place across Lincoln and Washington Counties afternoon due to very warm temperatures and low humidity. A few daily record high temperatures are possible as well. .DAYS TWO THROUGH SEVEN...Wednesday through Monday Dry conditions with above normal temperatures expected across the plains Wednesday and Thursday, with a chance of showers each afternoon in the mountains. Winds will increase on Wednesday and will result in elevated to critical fire weather conditions across the plains and possibly South Park. Although temperatures will not be as warm on Thursday, stronger winds are expected across the plains which will again likely bring elevated to critical fire weather conditions to those areas. The next system arrives Friday which may bring increasing chances of precipitation to the region along with much cooler temperatures through Saturday. Drier and warmer weather will return on Sunday. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed today or tonight.
The national radar mosaic for the moment the first event began.
1 avalanche. Local standard time, as filed.
Berthoud Pass was closed for hours south of Winter Park due to a snow slide that was blocking the roadway.
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: 1084364.