Alert archive / Utah / Flash Flood Warnings in 2003

Flash Flood Warning 32, NWS Salt Lake City, UT

August 21, 2003Utah County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Aug 21, 2003, 5:35 PM MDT for Utah County, Utah. It was in force for 55 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Aug 21, 2003, 5:35 PM MDT (23:35 UTC)
Expired: Aug 21, 2003, 6:30 PM MDT
In force: 55 min
Issued by: NWS Salt Lake City, UT
Area: Counties, with a storm outline in the text

County Utah County, UT

The radar

The Salt Lake City radar (KMTX), 138 km from the middle of the area, began a volume at 23:39 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 12:00Z, 11.6 hours before the alert went out and 69 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 10 J/kg
Mixed-layer CIN: -239 J/kg
Mixed-layer LCL: 2635 m above ground
0-6 km bulk shear: 10 kt
0-1 km storm-relative helicity: 15 m²/s²
0-3 km storm-relative helicity: 48 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 
WGUS55 KSLC 212336
FFWSLC
UTC049-220030-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
535 PM MDT THU AUG 21 2003

THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL UTAH COUNTY IN UTAH

* UNTIL 630 PM MDT

* AT 530 PM MDT...WEATHER SERVICE DOPPLER RADAR INDICATED VERY       
  HEAVY RAIN OVER SPRINGVILLE...OR ABOUT 8 MILES SOUTHEAST OF        
  PROVO. THESE STORMS ARE REFORMING IN THIS AREA.

THIS WARNING IS SPECIFICALLY FOR THE BURN AREAS IN THE BUCKLEY DRAW 
JUST NORTH OF SPRINGVILLE AND IN ROCK CANYON EAST OF PROVO.

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF CREEKS
AND STREAMS...ROADS AND ROADSIDE CULVERTS. THE HEAVY RAINS COULD ALSO
TRIGGER ROCK AND MUDSLIDES IN STEEP TERRAIN.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE. IF YOUR VEHICLE STALLS, ABANDON IT IMMEDIATELY AND SEEK
HIGHER GROUND.

TO REPORT SEVERE WEATHER HAVE THE NEAREST LAW ENFORCEMENT AGENCY
RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE IN
SALT LAKE CITY.

LAT...LON 4026 11160 4015 11162 4014 11148 4028 11147


$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 21, 2:22 PM MDT	Severe Thunderstorm Warning	SLC	Kane	38 min
Aug 21, 2:35 PM MDT	Severe Thunderstorm Warning	SLC	Kane	25 min
Aug 21, 4:33 PM MDT	Flash Flood Warning	SLC	Utah	57 min

Nearby

Flash Flood Warnings in Utah, 2003 Every flash flood warning in 2003

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.