Alert archive / Utah / Flash Flood Warnings in 1998

Flash Flood Warning 11, NWS Salt Lake City, UT

July 24, 1998Summit County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Jul 24, 1998, 6:29 PM MDT for Summit County, Utah. It was in force for 2 hr. 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
Jul 24, 1998, 6:29 PM MDT (00:29 UTC)
Expired
Jul 24, 1998, 8:30 PM MDT
In force
2 hr
Issued by
NWS Salt Lake City, UT
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Summit County, UT

The radar

The Salt Lake City radar (KMTX), 103 km from the middle of the area, began a volume at 00:30 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Salt Lake City I, UT (KSLC), launched 00:00Z, 0.5 hours before the alert went out and 41 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, Salt Lake City I, UT at 00:00Z on 1998-07-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 408 joules per kilogram.LCLLFCEL10008507005003002001001 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, Salt Lake City I, UT at 00:00Z on 1998-07-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 15 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
408 J/kg
Mixed-layer CIN
-21 J/kg
Mixed-layer LCL
1293 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
15 m²/s²
0-3 km storm-relative helicity
62 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSLC 250036
FFWSLC
UTC043-250230-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
629 PM MDT FRI JUL 24 1998

THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY HAS ISSUED A

   * FLASH FLOOD WARNING FOR...
     SOUTHWESTERN SUMMIT COUNTY IN UTAH

   * UNTIL 830 PM MDT

   * AT 624 PM MDT WEATHER SERVICE DOPPLER RADAR AND SPOTTER         
     REPORTS INDICATE VERY HEAVY RAIN FALLING ALONG I-80 IN          
     SOUTHWEST SUMMIT COUNTY.  A WEATHER SERVICE SPOTTER IN THE
     KIMBALL JUNCTION AREA REPORTS 1.60 INCHES OF RAIN HAS FALLEN 
     IN LESS THAN AN HOUR.  RADAR ESTIMATES INDICATE AS MUCH AS 3    
     INCHES OF RAIN HAS FALLEN JUST SOUTH OF I-80 IN WHITE PINE      
     CANYON AREA. 

     NORMALLY DRY WASHES AND SMALL STREAMS WILL BE RUNNING FULL. 

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY.
MOVE TO HIGHER GROUND.


LAT...LON 4074 11162 4067 11149 4073 11114 4091 11121

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

In the hours before

Local storm report, Jul 24, 1:00 PM MDT, 5 hours 29 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE  SALT LAKE CITY UT
100 PM MDT FRI JUL 24 1998

TIME(MDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

1120 AM    NEWCASTLE                 UT   TORNADO
07/23/98   IRON                           TORNADO BRIEFLY TOUCHED
                                          DOWN OFF OF HIGHWAY 56
                                          SOUTHEAST OF NEWCASTLE.
                                          NO APPARENT DAMAGE.

0740 PM    NATURAL BRIDGES NM        UT   FLASH FLOODING
07/23/98   SAN JUAN                       FLASH FLOOD IN SEVERAL
                                          CANYONS AND SMALL STREAMS
                                          WITHIN PARK BOUNDARIES.

END

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 25, 3:14 AM MDTFlash Flood WarningSLCWeber3 hr

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; radar from the NEXRAD Level II archive.