Alert archive / Utah / Flash Flood Warnings in 1991

Flash Flood Warning 9, NWS Salt Lake City, UT

August 6, 1991Carbon County, Emery County, Sanpete County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Aug 6, 1991, 3:15 PM MDT for Carbon County, Emery County, Sanpete County, Utah. It was in force for 60 min.

The area

The counties it named.

The facts

Issued
Aug 6, 1991, 3:15 PM MDT (21:15 UTC)
Expired
Aug 6, 1991, 4:15 PM MDT
In force
60 min
Issued by
NWS Salt Lake City, UT
Area
Whole counties

Counties Carbon County, UT, Emery County, UT, Sanpete County, UT

The nearest sounding before it

Salt Lake City I, UT (KSLC), launched 12:00Z, 9.3 hours before the alert went out and 179 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 12:00Z on 1991-08-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 330 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 12:00Z on 1991-08-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 63 square meters per square second.19395878Sfc1 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
330 J/kg
Mixed-layer CIN
-224 J/kg
Mixed-layer LCL
2437 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
63 m²/s²
0-3 km storm-relative helicity
134 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 062117
FFWSLC
UTC039-007-015-061615-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
315 PM MDT TUE AUG 6 1991
 
THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL 415 PM MDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN CENTRAL UTAH
 
   ...EASTERN SAN PETE COUNTY
 
IN EAST CENTRAL UTAH
 
   ...WESTERN CARBON COUNTY...NORTHWESTERN EMERY COUNTY
 
LOCAL LAW ENFORCEMENT AND NATIONAL WEATHER SERVICE SPOTTERS HAVE
REPORTED HEAVY RAINFALL OF OVER ONE INCH FALLING IN THE WARNING AREA
WITHIN THE LAST HOUR ALONG WITH FLASH FLOODING OF WASHES AND SMALL
STREAMS.
 
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 LOW SPOTS IF WATER COVERS
THE ROADWAY.  NEVER TRY TO CROSS A FLOWING STREAM...EVEN A SMALL
ONE...ON FOOT.  TO ESCAPE RISING WATER MnOVE UP TO HIGHER GROUND.

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

Special weather statement, Aug 6, 9:25 AM MDT, 5 hours 50 minutes before
UTZ008-011>013-061900-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
930 AM MDT TUE AUG 6 1991

 ...THUNDERSTORMS OVER THE SOUTHEAST CORNER OF THE STATE...

THUNDERSTORMS ARE DEVELOPING OVER MUCH OF SOUTHEAST UTAH THIS
MORNING.  BLANDING REPORTED 0.35 INCHES IN ABOUT HALF AN HOUR.  OTHER
AREAS MAY HAVE RECEIVED GREATER AMOUNTS.  SEVERAL SPOTTERS IN
SOUTHERN SAN JUAN COUNTY REPORTED A VERY DARK THUNDERSTORM TO THE
SOUTH...AND SATELLITE PICTURES SUGGEST THAT THE THUNDERSTORM WILL
PASS ACROSS THE SOUTHEAST CORNER OF UTAH DURING THE NEXT SEVERAL
HOURS.  BRIEF HEAVY RAINFALL...FREQUENT LIGHTNING AND SMALL HAIL ARE
POSSIBLE WITH THIS STORM.

DUE TO THE RAINFALL OVER THE PAST FEW HOURS MANY OF THE DRY WASHES
MAY BEGIN TO RUN.  DO NOT ATTEMPT TO CROSS ROADS IF WATER HAS COVERED
THE ROADWAY.  REMEMBER ALSO THAT LIGHTNING IS A PROVEN KILLER.  IF
YOU ARE OUTDOORS WHEN THREATENING WEATHER APPROACHES SEEuK SHELTER
INDOORS OR IN A VEHICLE.

STAY TUNED TO NOAA WEATHER RADIO AND LOCAL OFFICIALS FOR FURTHER
STATEMENTS AND ADVISORIES.

MSL...1522Z
Special weather statement, Aug 6, 12:47 PM MDT, 2 hours 28 minutes before
UTZALL-062300-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1245 PM MDT TUE AUG 6 1991

 ...FLASH FLOOD WATCH UNTIL 630 TONIGHT FOR SOUTHEASTERN UTAH...
 ...THUNDERSTORMS CONTINUE OVER THE SOUTHERN HALF OF THE STATE...

THUNDERSTORMS ARE BEGINNING TO DEVELOP OVER SOUTHWESTERN UTAH AND ARE
SPREADING INTO THE CENTRAL PART OF THE STATE.  MEANWHILE STRONGER
THUNDERSTORMS THAT WERE OVER THE SOUTHEASTERN CORNER OF UTAH THIS
MORNING ARE WEAKENING AND MOVING INTO COLORADO.  HOWEVER...MORE
THUNDERSTORMS ARE DEVELOPING IN NORTHEASTERN ARIZONA.  AS AN UPPER
LEVEL DISTURBANCE MOVES ACROSS THE STATE FROM SOUTH TO NORTH TODAY
THE THUNDERSTORMS ARE EXPECTED TO CONTINUE TO DEVELOP AND SPREAD
NORTHWARD INTO NORTHERN UTAH.

SO FAR TODAY THUNDERSTORMS IN SOUTHEASTERN UTAH HAVE PRODUCED BRIEF
HEAVY RAINFALL AND FREQUENT LIGHTNING.  A FEW REPORTS OF RAINFALL AS
OF NOON INCLUDE 0.49 INCHES AT BLANDING...0.17 INCHES AT GREEN
RIVER...AND 0.25 AT HOLE IN THE ROCK.

THE MAIN THUNDERSTORM THREAT TODAY WILL BE GUSTY WINDS AND FREQUENT
LIGHTNING HOWEVER BRIEF HEAVY RAINFALL HAS CAUSED MANY DRY WASHES TO
RUN.  DO NOT ATTEMPT TO DRIVE THROUGH ANY AREAS WHERE WATER IS
COVERING ROADWAYS.   REMEMBER ALSO THAT LIGHTNING IS A PROVEN KILLER.
IF YOU ARE OUTDOORS WHEN THREATENING WEATHER APPROACHES SEEK SHELTER
INDOORS OR IN A VEHICLE.

STAY TUNED TO NOAA WEATHER RADIO AND LOCAL OFFICIALS FOR FURTHER
STATEMENTS AND ADVISORIES.

SJK/MSL...1845Z

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 5, 6:47 PM MDTFlash Flood WarningSLCEmery58 min
Aug 6, 3:37 PM MDTFlash Flood WarningSLCCarbon, Emery, Sanpete68 min
Aug 6, 3:37 PM MDTFlash Flood WarningSLCDuchesne68 min
Aug 6, 5:00 PM MDTFlash Flood WarningSLCDuchesne, Uintah60 min
Aug 6, 5:15 PM MDTFlash Flood WarningSLCCarbon2 hr

Nearby

Flash Flood Warnings in Utah, 1991Every flash flood warning in 1991

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.