Heavy rain fell over Capitol Reef National Park on August 10th, causing flash flooding in multiple parts of the park.
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.
Heavy rain fell over Capitol Reef National Park on August 10th, causing flash flooding in multiple parts of the park.
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 Aug 10, 10:02 AM MST, 2 hours 48 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SALT LAKE CITY UT 1102 AM MDT FRI AUG 10 2012 .SYNOPSIS...HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH THE WEEKEND. A WEAK SYSTEM WILL GRAZE NORTHERN UTAH AND SOUTHWEST WYOMING TODAY AND TONIGHT. && .DISCUSSION...THE MODERATELY MOIST AIRMASS IN PLACE WILL ONLY BECOME MORE SO TODAY IN ADVANCE OF APPROACHING TROUGH. SAID TROUGH CURRENTLY RESIDES ALONG THE OREGON COASTLINE WILL PASS NORTHERN UTAH OVERNIGHT TONIGHT INTO SATURDAY MORNING. WITH PWAT INCREASING TO OVER 2 STANDARD DEVIATIONS ABOVE THE NORM LATE TODAY AND TONIGHT ACROSS THE NORTH AND REMAINING NEAR NORMAL ACROSS THE SOUTH AREAL EXTENT OF CONVECTION WILL BE ON THE RISE OVER THE NEXT 24 HOURS...ESPECIALLY ACROSS THE NORTH. WEAK DISTURBANCES WITHIN RETURN FLOW FROM DOMINANT HIGH TO OUR SOUTHEAST WILL AID TO TRIGGER CONVECTION TODAY BEFORE PHASING WITH THE TROUGH TONIGHT. ALREADY HAVE WEAK CONVECTION ASSOCIATED WITH THESE WAVES OVER WEST-CENTRAL AND NORTHWESTERN UTAH THIS MORNING AS AN INDICATION OF WAVE PRESENCE. ACROSS THE NORTHERN HALF OF THE AREA AFTERNOON CONVECTION WILL BE AIDED BY DYNAMIC SUPPORT FROM SAID WAVES WHILST TERRAIN BASED CELLS WILL DOMINATE THE SOUTHERN HALF OF THE AREA. CONTINUED SUPPORT TONIGHT WITH TROUGH PASSAGE SHOULD RETAIN NOCTURNAL CONVECTION ACROSS THE NORTH WITH AID OF MID LEVEL AXIS PASSAGE AND MORE FAVORABLE JET SUPPORT ALOFT. WARM AIRMASS IN PLACE WILL RETAIN ABOVE CLIMO TEMPS AREAWIDE TODAY BUT PORTIONS OF THE NORTH/WEST...INCLUDING THE WASATCH FRONT...SHOULD SEE SLIGHTLY COOLER VALUES DUE TO EXPANSIVE CLOUD COVER IN PLACE. GOING FORECAST IN FINE SHAPE. EARLIER AND MINIMAL UPDATE WAS TO DECREASE CLOUD COVER ACROSS THE SOUTHWEST DUE TO RAPID CLEARING. PREVIOUS DISCUSSION FOLLOWS... THE PACNW TROF PASSES EARLY SAT WITH GOOD SUBSIDENCE AND DRYING BEHIND IT ACROSS THE N BUT CENTRAL AND SRN UT SHOULD BE ACTIVE AGAIN SAT. THE CLOUDS AND SHOWERS COULD KNOCK A FEW DEGREES OFF THE HIGHS ACROSS THE NORTH ALTHO THIS MAY BE OFFSET SOMEWHAT BY A WARM START. THE NORTH REMAINS SUPPRESSED INTO SUN WHILE THE REST OF THE AREA IS ACTIVE ONCE AGAIN THEN MOISTURE RETURNS TO THE N SUNDAY NIGHT AND MON SHOULD BE AN ACTIVE DAY CWA-WIDE. THERE IS ENOUGH MOISTURE IN PLACE FOR AN ISOLATED FLASH FLOOD THREAT ACROSS MAINLY THE MORE FLOOD PRONE LOCATIONS IN SRN AND CENTRAL UT TODAY RIGHT THROUGH THE FIRST PART OF THE WEEK. THE HIGH BEGINS TO ELONGATE NWWD TUE AS ANOTHER STRONGER SHORT WAVE TROF CROSSES THE NRN ROCKIES AND MOVES INTO THE PLAINS. MODELS ARE NOT IN VERY GOOD AGREEMENT HOWEVER ON HOW THE HIGH RESPONDS TO THIS WAVE AND HOW MUCH DRYING OCCURS OVER THE CWA NORTH OF THE NW-SE ORIENTED RIDGE AXIS. HAVE TRENDED FORECASTS SOMEWHAT DRIER AFTER MID WEEK ALTHO NOT AS MUCH AS THE EC WOULD INDICATE. && .AVIATION...SOUTHEAST WINDS AT KSLC ARE EXPECTED THROUGH THE MORNING AND INTO THE EARLY AFTERNOON HOURS...WITH A 30 PERCENT CHANCE THAT THEY REMAIN IN PLACE THROUGH 22Z. THIS SAID...EXPECTING A SWITCH TO THE NORTHWEST IN THE 19-21Z WINDOW. INCREASED SHOWER AND THUNDERSTORM ACTIVITY WILL MOVE IN FROM THE SOUTH AND WEST THIS AFTERNOON AND REMAIN IN PLACE THROUGH TONIGHT. IN THE SHORT TERM A 40 PERCENT CHANCE EXISTS THAT STORMS WILL DIRECTLY IMPACT THE TERMINAL BETWEEN 23-03Z THIS EVENING...WITH A 70 PERCENT CHANCE FOR GUSTY OUTFLOW WINDS AT THE LEAST. STORMS COULD INTERMITTENTLY IMPACT THE TERMINAL THROUGH TONIGHT. && .FIRE WEATHER...A DISTURBANCE MOVING ACROSS THE PACIFIC NORTHWEST TODAY WILL MOVE THROUGH THE NORTHERN ROCKIES AND ENHANCE THE POSSIBILITY OF THUNDERSTORMS ACROSS MAINLY THE NORTHERN HALF OF UTAH TODAY THROUGH SATURDAY MORNING. THESE THUNDERSTORMS WILL PRODUCE LIGHTNING AND GUSTY WINDS BUT WILL LIKELY BE ACCOMPANIED BY RAIN AS WELL SO HAVE OPTED TO HOLD OFF ON A RED FLAG WARNING. AS THIS DISTURBANCE MOVES EAST...THE CONVECTIVE THREAT WILL DECREASE ACROSS THE FAR NORTH FOR SATURDAY INTO SUNDAY BUT WILL CONTINUE OVER THE REMAINDER OF THE AREA. WINDS OUTSIDE OF CONVECTION WILL BE MAINLY TERRAIN DRIVEN. && .SLC WATCHES/WARNINGS/ADVISORIES... UT...NONE. WY...&& MERRILL/KRUSE/WILENSKY 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 615 AM MDT FRI AUG 10 2012 UTZ001>016-019>021-517-518-WYZ021-111200- 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- 615 AM MDT FRI AUG 10 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE WESTERN TWO THIRDS OF UTAH AND SOUTHWEST WYOMING. .DAY ONE...TODAY AND TONIGHT SHOWERS AND THUNDERSTORMS WILL INCREASE IN COVERAGE TODAY AND CONTINUE THROUGH THE EVENING...WITH A FEW STORMS PERSISTING PAST MIDNIGHT. GUSTY WINDS AND LIGHTNING WILL ACCOMPANY THE THUNDERSTORMS. THERE IS ALSO A THREAT OF HEAVY RAIN WITH SOME OF THE STRONGER STORMS...AND ISOLATED FLASH FLOODING CANNOT BE RULED OUT...MAINLY ACROSS SOUTHERN AND EASTERN UTAH. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY THE HIGH WILL REMAIN LOCKED IN ACROSS THE GREAT BASIN THROUGH THE WEEKEND AND INTO THE FIRST PART OF NEXT WEEK KEEPING TEMPERATURES VERY WARM. AFTERNOON AND EVENING THUNDERSTORMS ARE POSSIBLE EACH DAY WITH A CONTINUED THREAT OF HEAVY RAIN AND ISOLATED FLASH FLOODING...MAINLY ACROSS THE EAST AND SOUTH. THE HIGH IS FORECAST TO SHIFT WEST TOWARDS THE MIDDLE PART OF NEXT WEEK CUTTING OFF THE MOISTURE SUPPLY AND STARTING A GRADUAL DRYING TREND. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. 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), 156 km away, was scanning. The volume nearest the first event began at 19:50 UTC.
1 flash flood. Local standard time, as filed.
Flash flooding was reported by the park rangers at Capitol Reef National Park. This flooding primarily occurred along the Scenic Drive, closing the Grand Wash and Capitol Gorge areas.
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, August 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: 409067.