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 Aug 23, 2:00 PM MST, 1 hour 20 minutes earlier.
UTAH AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SALT LAKE CITY UT 300 PM MDT SAT AUG 23 2003 .SYNOPSIS...A SOUTHWESTERLY FLOW WILL BE OVER THE AREA THROUGH SUNDAY. THE FLOW WILL BECOME LIGHT WESTERLY SUNDAY AND MONDAY. SOME DRYING WILL WORK INTO WESTERN AND NORTHERN UTAH TODAY. SLOW DRYING WILL CONTINUE OVER THE NORTH SUNDAY AND MONDAY WHILE THE SOUTH STAYS MOIST. .DISCUSSION...WORKING COMPUTER PROBLEMS AND SEVERE WEATHER TODAY. MORE STABLE AIR IS MOVING INTO NORTHERN UTAH WHILE THE SOUTH REMAINS UNSTABLE WITH FLASH FLOODING AND SOME HAIL OCCURRING. MODELS SHOW THE NORTHERN HALF OF THE AREA STABLE TOMORROW AND MONDAY WHILE MOISTURE AND INSTABILITY CONTINUES OVER THE SOUTH. THEN MOISTURE BEGINS TO SURGE NORTH AGAIN MONDAY NIGHT THROUGH MID-WEEK. SLC 2111 CDC 3333 GIBSON .SLC...NONE.
IDZ024-025-UTZ001>021-WYZ021-241300- HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE SALT LAKE CITY UT 309 PM MDT SAT AUG 23 2003 THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE WESTERN TWO-THIRDS OF UTAH...EXTREME SOUTHEAST IDAHO AND EXTREME SOUTHWEST WYOMING .DAY ONE... TODAY THUNDERSTORMS ARE PRODUCING LOCAL HEAVY RAIN OVER SOUTHERN UTAH. FLASH FLOODING IS A POSSIBILITY THROUGH THE EARLY EVENING TONIGHT. STAY TUNES TO NOAA WEATHER RADIO OR YOUR FAVORITE NEWS SOURCES FOR FURTHER INFORMATION ON THUNDERSTORMS TONIGHT. .DAYS TWO THROUGH SEVEN... SUNDAY THROUGH FRIDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
The Cedar City radar (KICX), 48 km away, was scanning. The volume nearest the first event began at 22:19 UTC.
1 flash flood. Local standard time, as filed.
Flash flooding and rock slides were reported over Highway 143 southeast of Parowan.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Utah in 2003Every state in 2003This day in weather historyWarnings in Utah, August 2003
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: 5380219.