Scattered afternoon thunderstorms moved over Gunnison, Colorado with lightning striking near a campground. The lightning directly impacted a local campground where 3 campers were injured.
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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 GJT wrote it up.
Scattered afternoon thunderstorms moved over Gunnison, Colorado with lightning striking near a campground. The lightning directly impacted a local campground where 3 campers were injured.
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 Jul 17, 1:48 PM MST, 57 minutes earlier.
Area Forecast Discussion National Weather Service Grand Junction CO 248 PM MDT Fri Jul 17 2020 .SHORT TERM...(Tonight through Saturday night) Issued at 224 PM MDT Fri Jul 17 2020 Scattered showers and thunderstorms have developed over the higher terrain as a result of peak heating. The increased moisture across the region has caused low-level RH to be higher and LCLs to be lower. It is also keeping the temperatures today a little closer to normal. The PWAT values range from 0.50 inches across the north where westerly winds are slightly drier to 0.80 inches closer to the Four Corner region. Weak southwesterly flow has been sufficient enough to keep cells propagating, but cells seem to be collapsing after a short amount of time. Can not rule out a few training cells in localized terrain features and given the moisture moderate to heavy rainfall could occur. The instability is roughly around 500 J/kg in spots and may also support brief small hail. Wind gusts from storm outflows may be as high as 30 mph through the late afternoon, they will allow the precipitation to move and develop over some of the valleys. Showers and storms will gradually dissipate this evening, but may continue for the San Juan and maybe the Elk mountains. Tomorrow the midlevel high pressure is still expected to split from the plains and move over the region, which means deeper westerlies into our area and drier air as the moisture plume is forced to the east. Residual moisture is likely to support some mountain showers and storms during the heating of the day though the best chances will be along the southern Divide area. The drier conditions will again push afternoon temperatures upward with upper 90s to triple digits returning to the lower deserts. .LONG TERM...(Sunday through Friday) Issued at 224 PM MDT Fri Jul 17 2020 By Sunday and Monday not much will change to the pattern besides dry air becomes slightly more entrenched over our area. This will keep a majority of the showers along and east of the Divide. Temperatures will run warmer than normal with highs in the 90s to 100s in the lower valleys to mid 70s to 80s in the mountain towns. The chances for moderate to heavy rainfall will trend downward with the dry air intrusion. The midlevel trough over the northern plains will continue drifting eastward early next week allowing the high to build back over the southern and central plains. At the same time the weak low pressure off the coast of California will interact with the trough deepening over the Pacific Northwest. This seems to keep the low in place for several days. As a result the sub-tropical moisture fetch will return out of the south-southwest perhaps as early as Tuesday. The models are struggling with the evolution of this weak cut off low pressure over the West Coast, which is fairly typical. The position and strength of this low will likely play role in exactly where this plume of tropical moisture sets up. If it gets too far over the Great Basin it opens the potential for dry air from the west, which does not seem to be the case at this point. Not to jump the gun but late in the week the models are generating fairly widespread QPF. A direct result of the expansive cloud cover and precipitation will be temperatures around normal or slightly below by mid to late week. Another thing to note is most of this warm season we have been dealing with a narrow plume of sub-tropical moisture mainly on the western periphery of the high. The models are now showing the potential for a broader plume overtaking the Desert Southwest and Four Corner region, which is a classic monsoon pattern given these synoptic feature placements. && .AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon) Issued at 1126 AM MDT Fri Jul 17 2020 Showers and thunderstorms firing off higher terrain will increase in coverage this afternoon, favoring the southern and central mountain ranges. Brief periods of heavy rain, gusty outflow winds and lightning are the main concerns with stronger storms. KTEX, KMTJ, KRIL, KASE, and KEGE may experience brief MVFR conditions due to passing rain showers, while other TAF sites along and south of the I-70 corridor will be impacted by gusty and erratic winds. Shower coverage will decrease after sunset, however, some nocturnal showers are still possible over higher terrain in southwest Colorado. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...None. UT...None. && SHORT TERM...KJS LONG TERM...KJS AVIATION...ERW
Hazardous Weather Outlook National Weather Service Grand Junction CO 504 AM MDT Fri Jul 17 2020 COZ001>014-017>023-UTZ022>025-027>029-181115- 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- 504 AM MDT Fri Jul 17 2020 This hazardous weather outlook is for eastern Utah and western Colorado. .DAY ONE...Today and Tonight Thunderstorm development will again occur with the heating of the day Gusty outflow winds be the main threat from storms. Brief moderate to heavy rainfall rates are possible with isolated storms in Southwest Colorado. Runoff from recent burn scars will need to be monitored. .DAYS TWO THROUGH SEVEN...Saturday through Thursday Thunderstorm development can be expected each day through Thursday with the best coverage remaining over the Colorado mountains through the weekend. Storm coverage could increase through the middle of next week. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed.
Special Weather Statement
National Weather Service Grand Junction CO
1247 PM MDT Fri Jul 17 2020
COZ020-UTZ028-171930-
Paradox Valley/Lower Dolores River CO-La Sal and Abajo Mountains UT-
1247 PM MDT Fri Jul 17 2020
...SPECIAL WEATHER STATEMENT...
At 1246 PM MDT, Doppler radar was tracking a strong thunderstorm 19
miles northeast of La Sal, moving northeast at 10 mph.
Half inch hail and winds in excess of 30 mph will be possible with
this slow moving storm.
This storm will remain over mainly rural areas of .
This includes Colorado 141 between mile markers 93 and 99, and near
mile marker 101.
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 3844 10908 3847 10913 3851 10913 3862 10897
3848 10884
TIME...MOT...LOC 1846Z 244DEG 8KT 3852 10903
ERWThe Grand Junction radar (KGJX), 125 km away, was scanning. The volume nearest the first event began at 21:43 UTC.
1 lightning. Local standard time, as filed.
Three individuals camping near Gunnison Colorado were struck by lightning as a thunderstorms passed through. All three were injured, with one 15 year old male seeking medical treatment.
As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.
| Event | Date | Age | Sex | Where | Kind |
|---|---|---|---|---|---|
| Lightning, Gunnison | 2020-07-17 | 50 | Female | Camping | Direct |
| Lightning, Gunnison | 2020-07-17 | 15 | Male | Camping | Direct |
| Lightning, Gunnison | 2020-07-17 | 15 | Male | Camping | Direct |
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2020Every state in 2020This day in weather historyWarnings in Colorado, July 2020
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: 946983.