Alert archive / Utah / Flash Flood Warnings in 1989

Flash Flood Warning 2, NWS Salt Lake City, UT

July 27, 1989Washington County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Jul 27, 1989, 5:20 PM MDT for Washington County, Utah. It was in force for 115 min.

The area

The counties it named.

The facts

Issued
Jul 27, 1989, 5:20 PM MDT (23:20 UTC)
Expired
Jul 27, 1989, 7:15 PM MDT
In force
115 min
Issued by
NWS Salt Lake City, UT
Area
Whole counties

County Washington County, UT

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Mercury/Desert R, NV (KDRA), launched 12:00Z, 11.3 hours before the alert went out and 234 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 12:00Z on 1989-07-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 12:00Z on 1989-07-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 38 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
0 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
38 m²/s²
0-3 km storm-relative helicity
-24 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 272322
FFWSLC
UTC053-280115-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
520 PM MDT THU JUL 27 1989
 
THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL  715 PM MDT
FOR PEOPLE IN THE FOLLOWING COUNTY...
 
IN SOUTHWEST UTAH
          ...EASTERN WASHINGTON COUNTY
 
THE UTAH HIGHWAY PATROL REPORTS FLOODING ACROSS HIGHWAY 9 BETWEEN
ROCKVILLE AND SPRINGDALE IN WASHINGTON COUNTY. WATER HAS COVERED THE
ROADWAY IN THIS AREA AND MOTORISTS SHOULD AVOID DRVING INTO THIS
SITUATION. SEVERAL OF THE NORMALLY DRY WASHES THAT FEED THE VIRGIN
RIVER HAVE FILLED TO CAPACITY AND ARE OVERFLOWING.
 
SPOTTERS IN THE AREA HAVE ALSO REPORTED HEAVY RAIN AND SMALL HAIL.
ONE SPOTTER IN SPRINGDALE RECEIVED 0.90 INCHES OF RAIN IN LESS THAN
HALF AN HOUR.
 
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.
 
MOST DEATHS IN FLASH FLOODING 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.

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, Jul 27, 5:07 PM MDT, 13 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
505 PM MDT THU JUL 27 1989

           ...HEAVY THUNDERSTORMS OVER THE SOUTHWEST...

SPOTTERS IN EASTERN WASHINGTON COUNTY INCLUDING ZION NATIONAL PARK HAVE
REPORTED HEAVY RAINFALL FROM A CLUSTER OF THUNDERSTORMS THAT HAS MOVED
NORTHWARD INTO THE STATE.  A SPOTTER IN SPRINGDALE RECEIVED 0.90 INCHES
OF RAIN IN LESS THAN 30 MINUTES.  SMALL HAIL HAS ACCOMPANIED THE HEAVY
RAINFALL.  THE PARK SERVICE IN ZION NATIONAL PARK REPORTED HEAVY
RAINFALL AND SMALL HAIL ALSO.  A SMALL ROCK SLIDE HAD OCCURRED OVER ONE
OF THE ROAD WAYS IN THE PARK.

RADAR INDICATES THAT THESE STORMS CONTINUE TO SHOW HEAVY RAINFALL AND
ARE MOVING SLOWLY NORTHWARD.  PERSONS DRIVING THROUGH THIS AREA OF THE
STATE... OR INVOLVED IN OUTDOOR ACTIVITIES SHOULD BE PREPARED FOR BRIEF
HEAVY RAINFALL AND SMALL HAIL.

ROCK SLIDES AND ROADWAYS COVERED WITH WATER MAY ALSO BE ENCOUNTERED.

ADDITIONAL STATEMENTS WILL BE ISSUED AS NEEDED.

DMC...2305Z

Nearby

Flash Flood Warnings in Utah, 1989Every flash flood warning in 1989

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.