Alert archive / Utah / Flash Flood Warnings in 1998

Flash Flood Warning 60, NWS Salt Lake City, UT

September 11, 1998Washington County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Sep 11, 1998, 10:56 AM MDT for Washington 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
Sep 11, 1998, 10:56 AM MDT (16:56 UTC)
Expired
Sep 11, 1998, 1:00 PM MDT
In force
2 hr
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

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 4.9 hours before the alert went out and 250 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, Flgstf/Belemont, AZ at 12:00Z on 1998-09-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Flgstf/Belemont, AZ at 12:00Z on 1998-09-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 31 square meters per square second.193958Sfc1 km3 km6 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1435 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
31 m²/s²
0-3 km storm-relative helicity
158 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 111702
FFWSLC
UTC053-111900-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1056 AM MDT FRI SEP 11 1998

THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY HAS BEEN EXTENDED

   * FLASH FLOOD WARNING FOR...
     EASTERN WASHINGTON COUNTY IN UTAH
     

   * UNTIL 100 PM MDT

   * ONLY LIGHT RAIN CONTINUES BUT RUNOFF FROM THE HEAVY RAIN THIS MORNING
WILL CONTINUE TO BRING RAPID RISES TO SMALL WASHES AS WELL AS THE 
VIRGIN RIVER AND TRIBUTARIES THROUGH EARLY AFTERNOON.



LAT...LON 3702 11333 3701 11290 3749 11289 3746 11325

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 10, 8:45 PM MDTSevere Thunderstorm WarningSLCSan Juan45 min
Sep 11, 8:39 AM MDTFlash Flood WarningSLCWashington2 hr
Sep 11, 10:15 AM MDTFlash Flood WarningSLCWashington45 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.