At the end of the first week of July, monsoon moisture moved into the state from the south. Thunderstorms developed in this moist airmass, producing the first flash floods in what would become a very active month for flash flooding.
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.
At the end of the first week of July, monsoon moisture moved into the state from the south. Thunderstorms developed in this moist airmass, producing the first flash floods in what would become a very active month for flash flooding. While this additional moisture did not end the wildfire season completely, it reduced the explosive fire behavior that had been observed in the last week of June and first week of July.
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 6, 8:59 AM MST, 4 hours 1 minute earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SALT LAKE CITY UT 959 AM MDT FRI JUL 6 2012 .SYNOPSIS...A SOMEWHAT MOIST AIRMASS WILL LINGER INTO THE UPCOMING WEEKEND AS HIGH PRESSURE ALOFT DEVELOPS OVER THE REGION. A WARMING TREND IS EXPECTED NEXT WEEK. && .DISCUSSION...THE WEATHER ACROSS UTAH IS SIGNIFICANTLY DIFFERENT THAN IT WAS 24 HOURS AGO...WITH YESTERDAYS RAIN AND OVERCAST SKIES REPLACED BY SUNNY SKIES IN MOST LOCATIONS. THE MAIN EXCEPTION TO THIS IS SOME ISOLATED FOG AND STRATUS THAT FORMED OVERNIGHT IN THE VERY MOIST BOUNDARY LAYER. SOME OF THIS FOG AND STRATUS HAS ERODED BETWEEN 13Z AND 16Z...AND THE REST IS EXPECTED TO DISSIPATE BY 18Z. A LARGE RIDGE REMAINS CENTERED OVER THE CENTRAL CONUS...WITH THE INTERMOUNTAIN WEST ON THE WESTERN FRINGES OF THAT RIDGE. THE SHORTWAVE THAT MOVED THROUGH THE CWA YESTERDAY CONTINUED TO MOVE NORTHEASTWARD OVERNIGHT...AND IS EXITING THE DAKOTAS THIS MORNING. HOWEVER...DEEPER MOISTURE STILL REMAINS IN PLACE OVER THE STATE...WITH THIS MORNINGS SLC SOUNDING STILL INDICATING A PRECIPITABLE WATER VALUE OF 1.09 INCHES. THOUGH THIS VALUE IS EXPECTED TO DECREASE A BIT OVER THE NEXT DAY OR TWO...THIS ADDITIONAL MOISTURE SHOULD HELP TO FUEL AFTERNOON CONVECTION TODAY AND HEADING INTO THE WEEKEND. WITH RELATIVELY LITTLE FORCING OR STEERING FLOW...EXPECT MOST OF THESE SHOWERS AND THUNDERSTORMS TO REMAIN TIED TO THE HIGHER TERRAIN. NO UPDATES TO THE FORECAST ARE PLANNED FOR THIS MORNING. && .AVIATION...VFR CONDITIONS WILL PREVAIL AT THE KSLC TERMINAL THROUGH THE FORECAST PERIOD. CUMULUS BUILDUPS ARE EXPECTED OVER THE SURROUNDING HIGHER TERRAIN AFTER 19Z. THESE BUILDUPS SHOULD REMAIN OVER/NEAR THE TERRAIN WITH LITTLE OR NO IMPACT ON THE TERMINAL AREA THROUGH 03Z. LIGHT AND VARIABLE WINDS THROUGH 17Z WILL GRADUAL TAKE ON A PREVAILING NORTHWEST DIRECTION BETWEEN 18-19Z. && .FIRE WEATHER...THE DEEP-LAYER MOISTURE PLUME OVER THE FIRE DISTRICTS THIS MORNING WILL REMAIN INTACT ACROSS EASTERN UTAH THROUGH THE WEEKEND. OVER THE WESTERN DISTRICTS MODEST DRYING WILL OCCUR...THOUGH EVEN THERE THE AVAILABLE MOISTURE WILL BE HIGHER THAN IS TYPICAL THIS TIME OF YEAR. THE BOTTOM LINE WILL BE THAT AFTERNOON AND EVENING CONVECTION WILL DEVELOP OVER THE HIGHER TERRAIN THROUGH THE WEEKEND...WILL SOME DRIFT INTO THE ADJACENT VALLEYS LATE IN THE DAY. ANY MOVEMENT OF THE SHOWERS/THUNDERSTORMS WILL BE SLOW AS THE MEAN LAYER WINDS LOOK TO BE ON THE LIGHT SIDE...ESPECIALLY OVER THE WEEKEND. THE LARGE DOME OF HIGH PRESSURE ALOFT OVER THE MIDWEST WILL RETURN TO THE INTERIOR WEST BY EARLY NEXT WEEK. WEAK FLOW AND TRAPPED MOISTURE WILL LEAD TO A CONTINUATION OF AFTERNOON/EVENING MOUNTAIN CONVECTION AROUND THE PERIPHERY OF THE HIGH PRESSURE. TEMPERATURES WILL BE SEASONALLY WARM WITH HUMIDITY VALUES LOW...BUT NOT EXTREMELY LOW AS THEY WERE DURING THE PAST SEVERAL WEEKS. && .SLC WATCHES/WARNINGS/ADVISORIES... UT...NONE. WY...NONE. && PUBLIC...SCHOENING FIRE WEATHER/AVIATION...CONGER FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT... HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE) FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION VISIT... HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE SALT LAKE CITY UT 245 AM MDT FRI JUL 6 2012 UTZ001>016-019>021-517-518-WYZ021-071300- 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- 245 AM MDT FRI JUL 6 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE WESTERN TWO THIRDS OF UTAH AND SOUTHWEST WYOMING. .DAY ONE...TODAY AND TONIGHT SCATTERED THUNDERSTORMS WILL DEVELOP MAINLY ALONG THE MOUNTAINS WITH A LOWER CHANCE OF IMPACT ACROSS ADJACENT VALLEYS. HOWEVER WITH MOISTURE REMAINING ELEVATED ACROSS THE REGION...CANNOT DISCOUNT THE CHANCE FOR LOCALIZED HEAVY RAIN OR FLASH FLOODING IN PRONE AREAS. .DAYS TWO THROUGH SEVEN...SATURADAY THROUGH THURSDAY SCATTERED THUNDERSTORMS WILL DEVELOP DAILY MAINLY ALONG THE MOUNTAINS WITH A LOWER CHANCE OF IMPACT ACROSS ADJACENT VALLEYS. HOWEVER WITH MOISTURE REMAINING ELEVATED ACROSS THE REGION...CANNOT DISCOUNT THE CHANCE FOR LOCALIZED HEAVY RAIN OR FLASH FLOODING IN PRONE AREAS. A WARMING TREND IS EXPECTED...WITH TEMPERATURES TOPPING OUT BETWEEN 95 AND 105 DEGREES EXPECTED SUNDAY THROUGH NEXT WEEK. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. ROGOWSKI FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT... HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE) FOR INFORMATION ON POTENTIAL TRAVEL IMPACTS VISIT... HTTP://WWW.UDOTTRAFFIC.UTAH.GOV/ROADWEATHERFORECAST.ASPX
The Cedar City radar (KICX), 36 km away, was scanning. The volume nearest the first event began at 19:59 UTC.
2 flash flood. Local standard time, as filed.
Flash flooding was reported in the Subway, a popular slot canyon in Zion National Park.
A debris flow occurred on the Seeley burn scar following heavy rains. The flooding originated from near Engineer Canyon, and crossed State Route 31.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Utah in 2012Every state in 2012This day in weather historyWarnings in Utah, July 2012
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: 403491, 403497.