Deep moisture returned to Utah on August 16th, picking up where it left off earlier in the month by causing widespread flash flooding and strong gusty winds.
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.
Deep moisture returned to Utah on August 16th, picking up where it left off earlier in the month by causing widespread flash flooding and strong gusty winds.
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 16, 9:55 AM MST, 4 hours 5 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SALT LAKE CITY UT 1055 AM MDT MON AUG 16 2010 .SYNOPSIS...A WEAK TROUGH OF LOW PRESSURE...WITH ASSOCIATED MOISTURE...WILL CROSS THE REGION THIS AFTERNOON AND EVENING. DRYER AIR WILL FILTER IN BEHIND THIS SYSTEM TONIGHT. MOISTURE WILL INCREASE AGAIN OVER THE AREA TUESDAY NIGHT AND WEDNESDAY...IN ADVANCE OF AN APPROACHING PACIFIC TROUGH. && .DISCUSSION...MORNING SATELLITE IMAGERY INDICATES A WEAK UPPER LEVEL DISTURBANCE...EMBEDDED IN UPPER TROUGH...OVER CENTRAL UTAH. SHOWER AND THUNDERSTORM ACTIVITY IN ASSOCIATION WITH THIS DISTURBANCE STILL PRESENT OVER EAST CENTRAL SECTIONS OF UTAH. ANOTHER DISTURBANCE IN WESTERLY FLOW SHOULD ENHANCE CONVECTIVE ACTIVITY OVER EAST CENTRAL AND SOUTHEAST SECTIONS THIS AFTERNOON...WHERE MOIST AIRMASS...WITH PRECIPITABLE WATER VALUES IN EXCESS OF AN INCH...REMAINS IN PLACE. LOW LEVEL CONVERGENCE ZONE OVER CENTRAL UTAH...SHOULD FOCUS DEVELOPMENT. STORM MOTION LOOKS TO BE AROUND 20 KNOTS...SO ANY FLASH FLOODING WOULD NEED TO BE IN ASSOCIATION WITH CELLS TRAINING ACROSS AN AREA. INSTABILITY LOOKS TO BE SOMEWHAT LIMITED...BUT WITH SHEAR VALUES NEAR 40 KTS...AN ISOLATED SEVERE STORM IS POSSIBLE. WITH RIDGE BUILDING INTO REGION...ANY EVENING CONVECTIVE ACTIVITY SHOULD DIMINISH QUICKLY. WILL UPDATE ZONE FORECAST TO INCREASE CHANCES FOR PRECIPITATION EAST CENTRAL AND SOUTHEAST SECTIONS THIS AFTERNOON. && .AVIATION...VFR CONDITIONS WILL CONTINUE AT THE KSLC TERMINAL THROUGH THE FORECAST PERIOD. CALM OR LIGHT SOUTHEAST WINDS ARE EXPECTED TO SHIFT TO THE NORTHWEST BY 19Z. THERE IS A 20 PERCENT FOR ERRATIC WINDS IN ASSOCIATION WITH CONVECTIVE ACTIVITY THIS AFTERNOON AND EVENING. && .FIRE WEATHER...A WEAK WEATHER DISTURBANCE PASSING THROUGH THE AREA WILL CONTINUE TO BRING SCATTERED SHOWERS AND THUNDERSTORMS TO PORTIONS OF CENTRAL AND EAST CENTRAL UTAH THROUGH THIS EVENING. HIGH PRESSURE IS EXPECTED TO BRIEFLY STRENGTHEN ACROSS THE AREA TUESDAY...BEFORE A STRENGTHENING SOUTHWESTERLY FLOW ALLOWS MOISTURE TO QUICKLY SPREAD NORTH ACROSS MOST OF UTAH WEDNESDAY...BRINGING A GOOD CHANCE FOR SHOWERS AND THUNDERSTORMS. A STORM SYSTEM PASSING THROUGH THE AREA LATE WEDNESDAY WILL SWEEP MUCH OF THIS MOISTURE OUT OF THE AREA BY LATE IN THE WEEK. && .SLC WATCHES/WARNINGS/ADVISORIES... UT...NONE. WY...NONE. && AVIATION...YOUNG FIRE WEATHER...SEAMAN PUBLIC...BARJENBRUCH 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)
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SALT LAKE CITY UT 1236 PM MDT MON AUG 16 2010 UTZ020-518-161900- SOUTH CENTRAL UTAH UT-SOUTHERN UTAH MOUNTAINS UT- 1236 PM MDT MON AUG 16 2010 ...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL GARFIELD COUNTY UNTIL 100 PM MDT... AT 1228 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM NEAR ESCALANTE...MOVING EAST AT 25 MPH. WIND GUSTS OF 40 TO 55 MPH ARE EXPECTED WITH THIS STORM...ALONG WITH HEAVY RAIN...DANGEROUS LIGHTNING AND SMALL HAIL. * LOCATIONS IMPACTED INCLUDE... ESCALANTE... THIS STORM IS CAPABLE OF PRODUCING GUSTY WIND...BRIEF HEAVY RAIN...DANGEROUS LIGHTNING AND SMALL HAIL. IF THREATENING WEATHER APPROACHES YOUR AREA...TAKE SHELTER IN A STURDY BUILDING. LAT...LON 3796 11120 3771 11115 3767 11173 3784 11177 TIME...MOT...LOC 1835Z 260DEG 20KT 3777 11164 YOUNG
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
136 PM MDT MON AUG 16 2010
UTZ013-020-518-162000-
SAN RAFAEL SWELL UT-SOUTH CENTRAL UTAH UT-SOUTHERN UTAH MOUNTAINS UT-
136 PM MDT MON AUG 16 2010
...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL GARFIELD COUNTY UNTIL 200
PM MDT...
AT 127 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 10 MILES SOUTHEAST OF BOULDER...OR 17 MILES EAST
OF ESCALANTE...MOVING EAST AT 20 MPH.
PENNY TO NICKEL SIZE HAIL IS EXPECTED WITH THIS STORM...ALONG WITH
BRIEF HEAVY RAIN AND FREQUENT DANGEROUS LIGHTNING.
* LOCATIONS IMPACTED INCLUDE...
RURAL CENTRAL GARFIELD COUNTY...
THIS STORM IS CAPABLE OF PRODUCING PENNY TO NICKEL SIZE HAIL. IF
THREATENING WEATHER APPROACHES YOUR AREA...TAKE SHELTER IN A STURDY
BUILDING.
LAT...LON 3772 11137 3790 11137 3796 11084 3768 11081
3768 11084 3767 11083 3766 11084
TIME...MOT...LOC 1935Z 270DEG 16KT 3781 11126
YOUNGSPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SALT LAKE CITY UT 248 PM MDT MON AUG 16 2010 UTZ013-020-021-162130- GLEN CANYON RECREATION AREA/LAKE POWELL UT-SAN RAFAEL SWELL UT-SOUTH CENTRAL UTAH UT- 248 PM MDT MON AUG 16 2010 ...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN KANE AND SOUTHEASTERN GARFIELD COUNTIES UNTIL 330 PM MDT... AT 240 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM 15 MILES NORTHWEST OF BULLFROG...OR 37 MILES EAST OF ESCALANTE...MOVING EAST AT 15 MPH. THIS CELL MAY BECOME STRONGER IN THE NEXT HOUR. PENNY TO NICKEL SIZE HAIL IS EXPECTED WITH THIS STORM. * LOCATIONS IMPACTED INCLUDE... BULLFROG... TICABOO... IF THREATENING WEATHER APPROACHES YOUR AREA...TAKE SHELTER IN A STURDY BUILDING. THIS STORM IS CAPABLE OF PRODUCING PENNY TO NICKEL SIZE HAIL. IF THREATENING WEATHER APPROACHES YOUR AREA...TAKE SHELTER IN A STURDY BUILDING. LAT...LON 3775 11049 3740 11077 3752 11108 3769 11105 TIME...MOT...LOC 2048Z 259DEG 15KT 3762 11091 YOUNG
The Cedar City radar (KICX), 173 km away, was scanning. The volume nearest the first event began at 21:01 UTC.
15 flash flood, 4 thunderstorm wind. Local standard time, as filed.
Flash flooding occurred in numerous slot canyons in the Glen Canyon National Recreation Area, including Moody Wash, East Moody Canyon, and Middle Moody Canyon. In addition, multiple roads were made impassable due to the flooding.
The Bullfrog Marina sensor recorded a maximum wind gust of 59 mph.
Strong thunderstorm winds caused damage in Richmond, snapping trees and telephone poles.
Multiple slot canyons were flooded on the western edge of Glen Canyon National Recreation Area, including Coyote Gulch. Roads were impassable near Coyote Gulch and Sunset Flats, and Hole-in-the-Rock road sustained damage.
Flash flooding occurred in Twenty-five Mile Wash. In addition, roads were impassable in the surrounding area, including damage to Hole-in-the-Rock road, further north than the road was damaged earlier in the day.
Heavy rain caused a flash flood at the Ivie Creek rest area, located at mile post 87 along I-70, with water and debris flowing into the rest area.
Flash flooding occurred in Grand Wash in Capitol Reef National Park, with water 6 to 8 feet deep in Grand Wash, as well as water from Grand Wash flowing across the Scenic Drive.
After 1.5 to 2.0 inches of rain fell near Parowan, flash flooding occurred on SR-143, with two feet of water and debris crossing the road.
Flash flooding was reported southwest of Green River, with rainfall of up to 5 inches recorded in the area.
Heavy rain over Johnson Pass caused mud and debris to flow across Highway 199, temporarily closing the road.
The English Village sensor in the Dugway Proving Ground mesonet recorded a wind gust of 59 mph.
The Fish Springs sensor in the Dugway Proving Ground mesonet recorded a maximum wind gust of 60 mph.
Flash flooding occurred in the early morning hours along the North Fork of the Virgin River, with the gauge there rising from 92 cfs to 1378 cfs in one hour.
Heavy rain caused a debris flow from the south end of the Corner Canyon burn scar, damaging about 20 homes with mud and debris. Highland Drive was closed, and the police station, courts, and city hall were all flooded.
Heavy rain caused flash flooding in Buckskin Gulch, with water flowing over nearby US-89.
Heavy rain caused flash flooding across the northern portions of Capitol Reef National Park, including Cathedral Valley, further damaging roads that were already in disrepair from previous flash flooding. In addition, several washes east of the park were flooded, and water was flowing over SR-24.
Flash flooding occurred along the Scenic Drive of Capitol Reef National Park, as well as the Grand Wash and several roads further south in the park.
Heavy rain caused flash flooding in Little Wild Horse Canyon, with water there estimated to be 10 feet deep. Several roads in the area were also washed out.
Multiple roads at the southern end of Capitol Reef National Park were flooded and damaged, most notably the Notom-Bullfrog road.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Utah in 2010Every state in 2010This day in weather historyWarnings in Utah, August 2010
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: 257975, 257682, 257686, 257977, 257976, 257979, 257981, 257983, 257987, 257985, 257683, 257684, 257993, 258852, 258009, 258011, 258013, 258016, 258019.