Alert archive / Utah / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 64, NWS Salt Lake City, UT

August 4, 2011Utah County, Utah

NWS Salt Lake City, UT issued this severe thunderstorm warning at Aug 4, 2011, 3:41 PM MDT for Utah County, Utah. It was in force for 64 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 4, 2011, 3:41 PM MDT (21:41 UTC)
Expired
Aug 4, 2011, 4:45 PM MDT
In force
64 min
Issued by
NWS Salt Lake City, UT
Area
Storm-based polygon

County Utah County, UT

The radar

The Salt Lake City radar (KMTX), 123 km from the middle of the area, began a volume at 21:45 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, 9.7 hours before the alert went out and 54 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 2011-08-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 228 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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 2011-08-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 23 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
228 J/kg
Mixed-layer CIN
-245 J/kg
Mixed-layer LCL
1745 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
23 m²/s²
0-3 km storm-relative helicity
52 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.

444 
WUUS55 KSLC 042141
SVRSLC
UTC049-042245-
/O.NEW.KSLC.SV.W.0064.110804T2141Z-110804T2245Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
341 PM MDT THU AUG 4 2011

THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTH CENTRAL UTAH COUNTY IN UTAH

* UNTIL 445 PM MDT

* AT 336 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED 8 MILES
  WEST OF OREM...OR 9 MILES WEST OF PROVO...MOVING NORTHEAST AT 15   
  MPH. A SEPERATE STORM NEAR KEARNS ALREADY PRODUCED PING PONG SIZE  
  HAIL.

* LOCATIONS IN THE WARNING INCLUDE...
  AMERICAN FORK... PROVO... OREM... LINDON... PLEASANT GROVE... MT
  TIMPANOGOS AND SUNDANCE

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE HAIL...AND DEADLY CLOUD
TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

&&

LAT...LON 4016 11184 4032 11196 4050 11158 4045 11161
      4042 11158 4036 11156 4034 11145 4030 11145
TIME...MOT...LOC 2140Z 240DEG 12KT 4027 11182

$$

ROGOWSKI
3 follow-up statements
266 
WWUS55 KSLC 042151
SVSSLC

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
351 PM MDT THU AUG 4 2011

UTC049-042245-
/O.CON.KSLC.SV.W.0064.000000T0000Z-110804T2245Z/
UTAH UT-
351 PM MDT THU AUG 4 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 445 PM MDT
FOR NORTH CENTRAL UTAH COUNTY...

AT 345 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS
LOCATED NEAR LINDON...OR ABOUT 8 MILES NORTHWEST OF PROVO...MOVING 
NORTHEAST AT 40 MPH. AT 330 PM...A SIMILAR STORM HAD PING PONG SIZE 
HAIL IN KEARNS.

* LOCATIONS IN THE WARNING INCLUDE...
  INTERSTATE 15 FROM AMERICAN FORK TO PROVO
  MT TIMPANOGOS AND SUNDANCE

LAT...LON 4016 11184 4036 11186 4050 11158 4046 11161
      4042 11158 4036 11156 4034 11145 4030 11145
TIME...MOT...LOC 2150Z 234DEG 36KT 4035 11173

$$

ROGOWSKI
846 
WWUS55 KSLC 042227
SVSSLC

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
427 PM MDT THU AUG 4 2011

UTC049-042245-
/O.CON.KSLC.SV.W.0064.000000T0000Z-110804T2245Z/
UTAH UT-
427 PM MDT THU AUG 4 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 445 PM MDT
FOR NORTH CENTRAL UTAH COUNTY...

AT 424 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS
LOCATED NEAR MT TIMPANOGOS...OR ABOUT 10 MILES NORTH OF PROVO...
MOVING NORTHEAST AT 20 MPH.

* LOCATIONS IN THE WARNING INCLUDE...
  RURAL NORTHERN UTAH COUNTY

LAT...LON 4034 11171 4040 11177 4050 11158 4045 11161
      4043 11159 4042 11158 4036 11156
TIME...MOT...LOC 2227Z 229DEG 16KT 4040 11166

$$

ROGOWSKI
581 
WWUS55 KSLC 042238
SVSSLC

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
438 PM MDT THU AUG 4 2011

UTC049-042248-
/O.EXP.KSLC.SV.W.0064.000000T0000Z-110804T2245Z/
UTAH UT-
438 PM MDT THU AUG 4 2011

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL UTAH COUNTY WILL
EXPIRE AT 445 PM MDT...

THE STORM HAS WEAKENED AND IS NO LONGER SEVERE. THEREFORE THE WARNING
HAS BEEN ALLOWED TO EXPIRE.

LAT...LON 4034 11171 4040 11177 4050 11158 4045 11161
      4043 11159 4042 11158 4036 11156
TIME...MOT...LOC 2238Z 229DEG 16KT 4043 11161

$$

ROGOWSKI

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 3, 6:26 PM MDTSpecial Weather StatementSLCPiute34 min
Aug 3, 8:54 PM MDTSpecial Weather StatementSLCPiute21 min
Aug 3, 10:26 PM MDTFlash Flood WarningSLCPiute, Sevier3 hr
Aug 4, 2:31 PM MDTSevere Thunderstorm WarningSLCJuab, Utah29 min
Aug 4, 3:14 PM MDTFlash Flood WarningSLCPiute3 hr
Aug 4, 3:27 PM MDTSevere Thunderstorm WarningSLCSalt Lake32 min
Aug 4, 3:28 PM MDTFlash Flood WarningSLCWayne4 hr
Aug 4, 3:31 PM MDTSevere Thunderstorm WarningSLCDuchesne59 min
Aug 4, 3:44 PM MDTFlash Flood WarningSLCGarfield, Piute117 min
Aug 4, 3:58 PM MDTFlash Flood WarningSLCWayne2 hr
Aug 4, 4:07 PM MDTSevere Thunderstorm WarningSLCSalt Lake, Utah38 min
Aug 4, 4:11 PM MDTSevere Thunderstorm WarningSLCDuchesne, Wasatch36 min
Aug 4, 4:43 PM MDTSevere Thunderstorm WarningSLCJuab62 min
Aug 4, 4:56 PM MDTSevere Thunderstorm WarningSLCEmery34 min
Aug 4, 5:27 PM MDTSevere Thunderstorm WarningSLCUtah63 min

Nearby

Severe Thunderstorm Warnings in Utah, 2011Every severe thunderstorm warning in 2011

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.