Pulses of monsoonal moisture paired with passing mid-level disturbances led to several days of orographic showers and thunderstorms across western Colorado. Some storms produced heavy rain which led to localized flooding and debris flows across some southwest and west-central counties, including over the Lake Christine Fire burn scar.
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.
Pulses of monsoonal moisture paired with passing mid-level disturbances led to several days of orographic showers and thunderstorms across western Colorado. Some storms produced heavy rain which led to localized flooding and debris flows across some southwest and west-central counties, including over the Lake Christine Fire burn scar.
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 Aug 3, 10:16 AM MST, 4 hours 44 minutes earlier.
Area Forecast Discussion National Weather Service Grand Junction CO 1116 AM MDT Sat Aug 3 2019 .SHORT TERM...(Today through Sunday) Issued at 313 AM MDT Sat Aug 3 2019 Enough moisture is lingering down south, allowing for isolated storms to continue through the early morning hours across the eastern San Juans and nearby valleys including Pagosa Springs. The 00Z GJT sounding yesterday still indicated 0.87 inches of precipitable water (PW). Expect this to be the trend again today with water vapor satellite imagery showing enough low and mid level moisture moving around the high into southeast Utah and southwest Colorado up towards the central Colorado divide. Much of east- central to northeast Utah and west- central to northwest Colorado remains much drier, where mostly sunny skies and warm temperatures similar to yesterday will prevail. Expect isolated to scattered storms to develop this afternoon over the San Juans, favoring eastern and southern portions, up towards the central Colorado divide mountains. Storms could drift into southern valleys late in the day. Another push of monsoonal moisture will work in from the southwest on Sunday, helped along by a shortwave rotating around the high and across our area. PW values climb above an inch towards 1.3 inches near the Four Corners, so do anticipate the moisture in combination with the forcing from the shortwave to allow for an increase in thunderstorm activity and coverage. Locally heavy rain is expected with the stronger cells. Temperatures will be a good 5 to 10 degrees cooler on Sunday compared to today, due to the increase in clouds and showers. .LONG TERM...(Sunday night through Friday) Issued at 313 AM MDT Sat Aug 3 2019 The shortwave pushing through to the east of the area Sunday night will allow the high pressure ridge to shift back to the west by Monday. Anticipate a downturn in storm activity Monday afternoon and Tuesday, as this shift will cut off the moisture feed from the southwest. However, enough moisture (PW values still around 0.75 inches Monday with a bit less on Tuesday) will be recycled underneath and around the high to allow for afternoon storms favoring the high terrain. The lower elevations should warm up and dry out though with temperatures returning to above normal levels early next week. A trough off the west coast will nudge inland by mid week, allowing the high pressure ridge to shift eastward, opening the door to another monsoonal moisture push. PW values increase above an inch by Wednesday with the peak Thursday into Friday as PW values approach 1.5 Thursday evening in some areas. This may be overdone, but the overall trend of increasing moisture mid to late week will allow for increasing thunderstorm chances and coverage. An embedded shortwave looks to move through Thursday evening, which may allow for overnight convection given the moisture increase as well. Model solutions can change looking that far out, so while low confidence exists in the details, the overall trend is for a more active period mid to late week with cooler, below normal temps as well. && .AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon) Issued at 1115 AM MDT Sat Aug 3 2019 Isolated to scattered storms will occur through 03Z this evening, mainly over the higher terrain. Breezy conditions expected late this afternoon into the early evening. Conditions will mainly be VFR for most TAF sites, with brief MVFR possible at the sites mentioned above in passing thunderstorms with gusty outflow winds to 40 kts possible. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...None. UT...None. && SHORT TERM...MDA LONG TERM...MDA AVIATION...JDC
Hazardous Weather Outlook National Weather Service Grand Junction CO 244 AM MDT Sat Aug 3 2019 COZ001>014-017>023-UTZ022>025-027>029-040845- 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- 244 AM MDT Sat Aug 3 2019 This hazardous weather outlook is for eastern Utah and western Colorado. .DAY ONE...Today and Tonight Isolated to scattered storms will focus over southwest Colorado and central Colorado divide mountains this afternoon with dry and warmer weather across the rest of the area. Storms may drift into southern valleys late in the day. Locally heavy rain, gusty outflow winds and lightning are the main hazards from these storms. .DAYS TWO THROUGH SEVEN...Sunday through Friday Another surge of monsoonal moisture is expected Sunday, allowing for an increase in thunderstorm coverage. A bit of a downturn is expected Monday and Tuesday with afternoon storms mainly over high terrain. Moisture will increase once again Wednesday through Friday, with increasing storm chances and coverage through the end of the week. Main hazards will continue to be local heavy rain and lightning. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed.
Special Weather Statement National Weather Service Grand Junction CO 309 PM MDT Sat Aug 3 2019 COZ019-023-032200- Southwest San Juan Mountains CO-San Juan River Basin CO- 309 PM MDT Sat Aug 3 2019 ...SIGNIFICANT WEATHER ADVISORY FOR EASTERN ARCHULETA COUNTY UNTIL 400 PM MDT... At 309 PM MDT, Doppler radar was tracking a strong thunderstorm 9 miles southeast of Pagosa Springs, or 19 miles north of Dulce, moving northeast at 5 mph. Dime size hail and winds in excess of 40 mph will be possible with this storm. This storm will remain over mainly rural areas of eastern Archuleta County. This includes U.S. Highway 84 in Colorado between mile markers 12 and 26. PRECAUTIONARY/PREPAREDNESS ACTIONS... Heavy rainfall is also occurring with this storm, and may lead to localized flooding. Do not drive your vehicle through flooded roadways. && LAT...LON 3708 10692 3724 10702 3735 10675 3714 10664 TIME...MOT...LOC 2109Z 239DEG 5KT 3720 10688 KJS
The national radar mosaic for the moment the first event began.
2 debris flow. Local standard time, as filed.
Showers and thunderstorms produced heavy rain which led to multiple mudslides along County Road 30 near Cinnamon Pass. The road was closed for an extended period of time. Several vehicles were stuck behind the mudslide and the occupants had to be rescued by Search and Rescue.
Numerous mudslides occurred 1 to 3 miles east of Basalt along Frying Pan Road as well as in the northwest side of town along Cedar and Pinion Drives in the Lake Christine Fire burn scar. The mud and debris closed several neighborhood roads with water flows estimated at 6 feet above normally dry channels, creeks, and washes. Drainage culverts were overwhelmed by mud and rocks flowing off the burn scar with 1 to 3 feet of ash-filled mud covering lawns and surrounding a few homes. Portions of Frying Pan Road were closed and, while the mud and debris flows that occurred were not associated with the Lake Christine Fire burn scar itself, the steep terrain and heavy rainfall still resulted in several vehicles being trapped by the flows. United States Geological Survey (USGS) rain gauges recorded about 1.60 inches of rain fell over the area in less than 2 hours.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2019Every state in 2019This day in weather historyWarnings in Colorado, August 2019
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: 835028, 836240.