1 flash flood, as filed by the National Weather Service.
Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. 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 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 Sep 12, 3:17 PM MST, 43 minutes earlier.
UTAH AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
417 PM MDT THU SEP 12 2002
.SYNOPSIS...AN UPPER LOW OVER CENTRAL UTAH WILL SLOWLY MOVE EAST OF
THE AREA BY FRIDAY AFTERNOON. A RIDGE OF HIGH PRESSURE WILL DEVELOP
OVER THE AREA FOR THE WEEKEND.
.DISCUSSION...UPPER LEVEL CIRCULATION OVER CENTRAL UTAH WITH MOST
AND UNSTABLE AIRMASS IN PLACE. FLASH FLOOD WATCH CONTINUED UNTIL 100
AND EXPANDED TO INCLUDE WASATCH MOUNTAINS SOUTH OF I-80 AND BOOK
CLIFFS. SLOW MOVING SHOWERS CONTINUE IN THAT AREA AND RECENT BURN
AREAS WILL BE AFFECTED.
UPPER LOW WILL BEGIN TO SHIFT EAST FRIDAY WITH LINGERING INSTABILITY
MOUNTAIN AND EAST. RIDGE BUILDS IN FOR SATURDAY AND SUNDAY. WINDS
MAY INCREASE WESTERN VALLEYS SUNDAY AS NEXT SYSTEM APPROACHES. 12Z
AVN SHOWS A TROF ROTATING NORTHEAST ACROSS THE NORTHERN GREAT BASIN
MONDAY MORNING. THIS MAY PUSH A MAINLY DRY BUT WINDY COLD FRONT INTO
UTAH. NEW AVN ALSO DEEPER WITH FOLLOWING SHORTWAVE FOR TUESDAY.
ADDED A SHOWER THREAT FOR MONDAY AND TUESDAY NORTHERN SECTIONS WITH
THESE SYSTEMS. DRY FOR WEDNESDAY AND THURSDAY AND COOL.
SLC 5210 CDC 4211 GIBSON
.SLC...FFASLC...FLASH FLOOD WATCH MOST OF CENTRAL AND SOUTHERN
UTAH UNTIL 1000 PM.The Grand Junction radar (KGJX), 214 km away, was scanning. The volume nearest the first event began at 23:02 UTC.
1 flash flood. Local standard time, as filed.
A cloudburst (1.48 inches in an hour) produced flash flooding in Sunnyside. City Hall was flooded with water up to 3 feet deep, and numerous homes and businesses were flooded.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Utah in 2002Every state in 2002This day in weather historyWarnings in Utah, September 2002
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: 5324783.