Alert archive / Utah / Flash Flood Warnings in 1998

Flash Flood Warning 44, NWS Salt Lake City, UT

August 30, 1998Washington County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Aug 30, 1998, 6:57 PM MDT for Washington County, Utah. It was in force for 63 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued
Aug 30, 1998, 6:57 PM MDT (00:57 UTC)
Expired
Aug 30, 1998, 8:00 PM MDT
In force
63 min
Issued by
NWS Salt Lake City, UT
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Washington County, UT

The nearest sounding before it

Mercury/Desert R, NV (KDRA), launched 00:00Z, 1.0 hours before the alert went out and 222 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Mercury/Desert R, NV at 00:00Z on 1998-08-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1125 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Mercury/Desert R, NV at 00:00Z on 1998-08-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 136 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1125 J/kg
Mixed-layer CIN
-41 J/kg
Mixed-layer LCL
3052 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
136 m²/s²
0-3 km storm-relative helicity
170 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.7

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KSLC 310102
FFWSLC
UTC053-310200-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
657 PM MDT SUN AUG 30 1998

THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY HAS ISSUED A

   * FLASH FLOOD WARNING FOR...
     CENTRAL WASHINGTON COUNTY IN UTAH
     INCLUDING ST GEORGE

   * UNTIL 800 PM MDT

   * AT 649 PM MDT THE PUBLIC REPORTED FLASH FLOODING IN THE ST 
     GEORGE AND WASHINGTON CITY AREA. 

   * OTHER LOCATIONS IN THE WARNING INCLUDE TOQUERVILLE...SANTA 
     CLARA...GUNLOCK AND HURRICANE

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF SMALL 
CREEKS AND STREAMS...HIGHWAYS AND UNDERPASSES. ADDITIONALLY...OTHER 
LOW LYING AREAS ARE SUBJECT TO FLASH FLOODING.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS OCCURRING OR IS 
IMMINENT. MOST FLASH FLOOD DEATHS OCCUR IN AUTOMOBILES. DO NOT 
ATTEMPT TO CROSS BRIDGES...DIPS...OR OTHER LOW SPOTS IF WATER COVERS 
THE ROADWAY. NEVER TRY TO CROSS A FLOWING STREAM...EVEN A SMALL 
ONE...ON FOOT. TO ESCAPE RISING WATER MOVE UP TO HIGHER GROUND.

TO REPORT FLASH FLOODING HAVE THE NEAREST LAW ENFORCEMENT AGENCY
RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY.
STAY TUNEDr TO LOCAL TELEVISION...RADIO...CABLE TV...OR NOAA WEATHER
RADIO FOR UPDATES.

LAT...LON 3701 11377 3703 11330 3729 11328 3730 11380

The office that day

Everything else NWS Salt Lake City, UT issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 30, 6:28 PM MDTSevere Thunderstorm WarningSLCWashington32 min
Aug 30, 7:46 PM MDTFlash Flood WarningSLCWashington74 min

Nearby

Flash Flood Warnings in Utah, 1998Every flash flood warning in 1998

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive.