A storm system moved across the Great Basin, triggering numerous thunderstorms.
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 SLC wrote it up.
A storm system moved across the Great Basin, triggering numerous thunderstorms.
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 Salt Lake City, UT wrote its last area forecast discussion before the first event at Jul 27, 9:16 AM MST, 3 hours 24 minutes earlier.
Area Forecast Discussion National Weather Service Salt Lake City UT 1016 AM MDT Mon Jul 27 2020 .SYNOPSIS...An upper level trough will move across the Great Basin today through tonight from southwest to northeast. High pressure aloft will strengthen over the interior west beginning midweek, bringing hot and dry conditions through the end of the week. && .DISCUSSION...A weak disturbance moving northeast across the southern Wasatch Front at sunrise created a swath of clouds and a few showers but has now mostly moved into southwest Wyoming. Clouds have been decreasing in Wasatch Back and this trend is expected to continue into southwest Wyoming by midday. Made an update earlier to reflect this change. Farther south, the leading edge of the upper level trough swinging across the Great Basin is creating a few showers and thunderstorms along the Nevada/Utah border west of Cedar City this morning. As this trough moves northeast into Utah this afternoon showers and thunderstorms will become more widespread. However, there is somewhat of a subsidence layer between 460-500mb that was observed on the SLC and Flagstaff 12Z sounding this morning which will inhibit most convection east of I-15 through midday. As the trough moves into southwestern Utah early this afternoon this cap is expected to dissolve over the southwest initially and then west central and the south this afternoon and into northern Utah late this afternoon through tonight. The 300 mb trough becomes more negatively tilted by this evening creating more widespread and stronger lift. Current forecast looks reasonable with higher PoPs moving into northern Utah tonight, although may have to expand the likely PoPs beyond midnight across the north. Also, the trend of lowering PoPs across the south is on target as well with the subsidence behind the trough likely to kill the convection rather rapidly this evening. Have lowered the PoPs across the southwest and south for this morning due to the aforementioned reasoning. Rest of package in good shape. && .AVIATION...Light southerly flow should switch to a light northerly flow around 21z. Vicinity showers by 00z will develop along the higher terrain. Scattered clouds along the terrain may obscure the mountains after 00z. There is a 30% change for some embedded thunderstorms that may bring additional hazards to the terminal beginning around 02z. && .SLC WATCHES/WARNINGS/ADVISORIES... UT...None. WY...None. && PUBLIC...Struthwolf AVIATION...Woodward For more information from NOAA's National Weather Service visit... http://weather.gov/saltlakecity For frequently asked questions about the Area Forecast Discussion visit... http://weather.gov/saltlakecity/general/afd_faqs.php
Hazardous Weather Outlook National Weather Service Salt Lake City UT 619 AM MDT Mon Jul 27 2020 UTZ001>016-019>021-517-518-WYZ021-281200- Cache Valley/Utah Portion-Northern Wasatch Front- Salt Lake and Tooele Valleys-Southern Wasatch Front- Great Salt Lake Desert and Mountains-Wasatch Mountain Valleys- Wasatch Mountains I-80 North-Wasatch Mountains South of I-80- Western Uinta Mountains-Wasatch Plateau/Book Cliffs- Western Uinta Basin-Castle Country-San Rafael Swell- Sanpete/Sevier Valleys-West Central Utah-Southwest Utah- Utahs Dixie and Zion National Park-South Central Utah- Glen Canyon Recreation Area/Lake Powell-Central Mountains- Southern Mountains-Southwest Wyoming- 619 AM MDT Mon Jul 27 2020 This Hazardous Weather Outlook is for the western two thirds of Utah and southwest Wyoming. .DAY ONE...Today and Tonight A weather system will bring showers and thunderstorms to much of the area today. Lightning and strong gusty winds will be the main threats with these storms, with locally heavy rainfall also possible. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday Showers and thunderstorms will remain possible Tuesday across northern Utah and southwest Wyoming. Otherwise high pressure will bring hot and dry conditions to the outlook area through the remainder of the week and into the upcoming weekend. .SPOTTER INFORMATION STATEMENT... Spotter activation may be needed. Please relay any information about observed severe weather to the NWS while following all local, state, and CDC guidelines. For more information from NOAA/s National Weather Service visit... http://weather.gov/saltlakecity For information on potential road travel impacts visit... http://www.udottraffic.utah.gov/roadweatherforecast.aspx
The Cedar City radar (KICX), 93 km away, was scanning. The volume nearest the first event began at 19:37 UTC.
8 thunderstorm wind, 1 flash flood. Local standard time, as filed.
A peak wind gust of 58 mph was recorded by the Milford sensor.
Sulphur Creek in Capitol Reef National Park rose 3 feet near Holt Draw on the west edge of the Park. In addition, state Route 24 was closed at milepost 82 due to flooding.
A peak wind gust of 66 mph was measured by the U.S. Army Dugway Proving Ground Target S sensor.
A peak wind gust of 59 mph was measured by the Flux sensor.
A peak wind gust of 65 mph was recorded by the I-80 at MP 81 Dolomite sensor.
A peak wind gust of 58 mph was recorded by the I-80 at MP 79 Timpie sensor.
A peak wind gust of 60 mph was recorded by the Beach sensor.
A peak wind gust of 67 mph was recorded by the Fremont Island sensor.
A peak wind gust of 63 mph was recorded by the Hat Island sensor.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Utah in 2020Every state in 2020This day in weather historyWarnings in Utah, 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: 908037, 913272, 908038, 908040, 908041, 908042, 908043, 908044, 908045.