Thunderstorms continued across southern Utah during the last week of August, with a couple of flash floods reported in far southern Utah. A lightning fatality also occurred in northern Utah during this period of time.
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.
Thunderstorms continued across southern Utah during the last week of August, with a couple of flash floods reported in far southern Utah. A lightning fatality also occurred in northern Utah during this period of time.
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 26, 3:15 PM MST, 3 hours 15 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SALT LAKE CITY UT 415 PM MDT WED AUG 26 2015 .SYNOPSIS...A LOW PRESSURE SYSTEM WILL SLOWLY TRANSLATE NORTHEAST OF THE AREA TONIGHT. HIGH PRESSURE WILL RETURN FOR THE LATTER HALF OF THE WEEK INTO THE UPCOMING WEEKEND. && .DISCUSSION...THE MID LEVEL CIRCULATION OF A LOW EMBEDDED WITHIN DEEPLY MOIST SOUTHWESTERLY FLOW HAS SLOWLY TRANSLATED NORTHEAST INTO NORTH CENTRAL UTAH TODAY. THE ASSOCIATED TROUGH AXIS EXTENDS SOUTH ROUGHLY FROM KSLC TO KPUC TO KPGA AND IS SLOWLY TRANSLATING EAST-NORTHEAST AS WELL. SUBSIDENCE IN LEE OF THIS AXIS CAN BE NOTED ACROSS THE MUCH OF THE WESTERN HALF OF THE STATE AS CONVECTION HAS BECOME QUITE SUPPRESSED...THOUGH A MODEST INSTABILITY AXIS EXISTS FROM SOUTHWEST UTAH NORTHWEST INTO NEVADA WHERE SCATTERED CONVECTION IS REFORMING AIDED BY MODEST DIFFERENTIAL HEATING WHERE CLOUDS HAVE THINNED. THOUGH THE BULK OF ONGOING PRECIPITATION EAST OF THE AXIS REMAINS ON THE LIGHT AND SHOWERY SIDE...THE ADDED FORCING ALONG ITS SOUTHERN TAIL BENEATH WEAK DEFORMATION ALOFT HAS SPARKED MULTI CELLULAR CONVECTION FROM LAKE POWELL SOUTH INTO NORTHERN ARIZONA...SOME STRONG. HANGING ONTO TO ONE LAST AREAL FLOOD WARNING ACROSS THE SOUTHEAST BET EXPECT THIS TO EXPIRE ON TIME IN A LITTLE OVER AN HOURS TIME. CONTINUED NORTHEAST PROGRESSION OF THE LOW AND ITS AXIS WILL ALLOW FOR A NET DECREASING TREND IN COVERAGE THIS EVENING AND OVERNIGHT FOR ALL AREAS OUTSIDE OF THE EAST. OVER THE NEXT 24 HOURS THE MID LEVELS WILL BEGIN TO DRY AS HIGH PRESSURE REBOUNDS AND EXPANDS NORTHEAST WITH ITS AXIS STRETCHING FROM THE DESERT SOUTHWEST INTO CENTRAL NEVADA. LACK OF SUBSTANTIAL BOUNDARY LAYER FLOW WILL LIMIT MUCH DRYING OF THE LOW LEVELS HOWEVER...AND EXPECT ISOLATED TO WIDELY SCATTERED CONVECTION TO REDEVELOP TOMORROW AFTERNOON WITH FOCUS OVER AND NEAR THE TERRAIN. UPDRAFTS WILL HAVE TO OVERCOME INCREASED LARGE SCALE SUBSIDENCE DUE TO THE BUILDING RIDGE. TEMPS WILL REBOUND AS SUCH ALLOWING A NET WARMING TREND ALL AREAS. AS THE DEEP UPPER LOW CURRENTLY OFF THE PACNW STATES OPENS AND LIFTS NORTHEAST TOMORROW THROUGH FRIDAY...THE AFOREMENTIONED RIDGE AXIS WILL SHIFT OVERHEAD THEN EAST OF THE AREA ALLOWING A DRYING SOUTHWESTERLY FLOW TO SPREAD ACROSS THE EASTERN GREAT BASIN STATES. A SERIES OF PROGRESSIVE SHORT WAVES WILL CONTINUE TO RELOAD THE PACNW THROUGH THROUGH THE WEEKEND SUPPRESSING THE HIGH SOUTH AND EAST AS THEY LIFT INLAND...THIS LIMITING ANY ISOLATED CONVECTIVE THREATS TO NAMELY AREAS CLOSEST TO THE UPPER JET AS IT SHIFTS INTO NORTHWESTERN UTAH EARLY NEXT WEEK. THE AFOREMENTIONED WARMING TREND WILL CONTINUE THROUGH SATURDAY BEFORE WEAK MID LEVEL CAA ADVECTION LOWERS THEM BACK TO NEAR NORMAL VALUES FOR EARLY NEXT WEEK. && .AVIATION...ERRATIC WINDS WILL CONTINUE AT THE SLC TERMINAL INTO THE EVENING. EXPECT WINDS TO EVENTUALLY BECOME MAINLY SOUTHERLY AFTER 23Z AND REMAIN SO THROUGH THE NIGHT. A FEW SHOWERS WILL REMAIN POSSIBLE...THOUGH THE THREAT OF THUNDERSTORMS IS LOW. && .FIRE WEATHER...A WEAK STORM SYSTEM INTERACTING WITH MONSOON MOISTURE IS RESULTING IN WIDESPREAD SHOWERS AND ISOLATED THUNDERSTORMS ACROSS UTAH TODAY. COVERAGE OF PRECIPITATION WILL DIMINISH THIS EVENING. AN UPPER LEVEL RIDGE BUILDS OVER THE REGION BEGINNING ON THURSDAY WHICH WILL BRING A WARMING AND DRYING TREND TO THE AREA. LINGERING MOISTURE WILL RESULT IN A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS ON THURSDAY AFTERNOON AND EVENING ACROSS NEARLY ALL OF SOUTHERN UTAH AND THE MOUNTAINS OF NORTHERN UTAH. WINDS ON THURSDAY ARE EXPECTED TO BE PRIMARILY TERRAIN DRIVEN. A STORM SYSTEM WILL MOVE INTO THE PACIFIC NORTHWEST LATE IN THE WEEK INTO THE WEEKEND AND THIS WILL RESULT IN THE DEVELOPMENT OF STRONGER SOUTH WINDS ACROSS THE AREA BY SATURDAY. && .SLC WATCHES/WARNINGS/ADVISORIES... UT...NONE. WY...NONE. && MERRILL/KRUSE/GRAHAM 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 423 AM MDT WED AUG 26 2015 UTZ001>016-019>021-517-518-WYZ021-271200- 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- 423 AM MDT WED AUG 26 2015 THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE WESTERN TWO THIRDS OF UTAH AND SOUTHWEST WYOMING. .DAY ONE...TODAY AND TONIGHT A WEATHER SYSTEM WILL SLOWLY CROSS THE OUTLOOK AREA TODAY BRINGING NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS. LOCALLY HEAVY RAINFALL WILL BE POSSIBLE WITH THE STRONGEST STORMS...WITH ISOLATED INSTANCES OF FLASH FLOODING POSSIBLE IN SLOT CANYONS...NORMALLY DRY WASHES AND SLICKROCK AREAS. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY HIGH PRESSURE WILL RETURN THURSDAY BRINGING A WARMING AND DRYING TREND THROUGH THE REMAINDER OF THE WEEK. LOCALLY BREEZY CONDITIONS ARE POSSIBLE OVER THE WEEKEND ACROSS WESTERN UTAH...WHICH COULD RESULT IN LOCAL CRITICAL FIRE WEATHER CONDITIONS. .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 ROAD TRAVEL IMPACTS VISIT... HTTP://WWW.UDOTTRAFFIC.UTAH.GOV/ROADWEATHERFORECAST.ASPX
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SALT LAKE CITY UT 240 PM MDT WED AUG 26 2015 UTZ020-021-262130- GLEN CANYON RECREATION AREA/LAKE POWELL UT-SOUTH CENTRAL UTAH UT- 240 PM MDT WED AUG 26 2015 ...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN SAN JUAN AND SOUTH CENTRAL KANE COUNTIES UNTIL 330 PM MDT... AT 238 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM OVER BIG WATER...OR 14 MILES NORTHWEST OF PAGE... MOVING NORTHEAST AT 15 MPH. HALF INCH HAIL AND WINDS IN EXCESS OF 40 MPH WILL BE POSSIBLE. THIS THUNDERSTORM MAY CREATE ROUGH CONDITIONS ON LAKE POWELL. A SIGNIFICANT AMOUNT OF SMALL HAIL IS FALLING WITH THIS STORM...AND MAY ACCUMULATE ON AREA ROADWAYS INCLUDING US 89 FROM BIG WATER TO THE UTAH AND ARIZONA BORDER. LOCATIONS IMPACTED INCLUDE... BIG WATER. PRECAUTIONARY/PREPAREDNESS ACTIONS... THIS STORM IS CAPABLE OF PRODUCING A SIGNIFICANT AMOUNT OF HAIL. HAIL MAY ACCUMULATE ON AREA ROADS RESULTING IN DANGEROUS TRAVEL CONDITIONS. IF ON OR NEAR LAKE POWELL...GET OUT OF THE WATER AND MOVE INDOORS OR INSIDE A VEHICLE. REMEMBER...LIGHTNING CAN STRIKE OUT TO 15 MILES FROM THE PARENT THUNDERSTORM. IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE STRUCK BY LIGHTNING. MOVE TO SAFE SHELTER NOW. DO NOT BE CAUGHT ON THE WATER IN A THUNDERSTORM. && LAT...LON 3709 11177 3727 11143 3700 11127 3700 11173 TIME...MOT...LOC 2038Z 244DEG 13KT 3704 11166 CRK
The Cedar City radar (KICX), 43 km away, was scanning. The volume nearest the first event began at 01:28 UTC.
2 flash flood, 1 lightning. Local standard time, as filed.
Park rangers reported flash flooding in the Pine Creek slot canyon, with extreme used to described the flooding.
A family was having a picnic in a park in Lehi, Utah, when a thunderstorm moved across the area. Lightning struck a nearby tree, and critically injured a 50-year-old woman. No one else in the party was seriously injured, but the victim passed away in a hospital a few days later.
Very heavy rain caused a massive flash flood along Wahweap Creek. The flood wave was caught on video and it carried full size dead trees left over from previous smaller floods, along with boulders the size of cars.
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, Utah | 2015-08-30 | 50 | Female | Under Tree | Direct |
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Utah in 2015Every state in 2015This day in weather historyWarnings in Utah, August 2015
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: 599451, 602095, 599452.