Alert archive / Utah / Severe Thunderstorm Warnings in 2011
Severe Thunderstorm Warning 9, NWS Salt Lake City, UT
NWS Salt Lake City, UT issued this severe thunderstorm warning at Apr 21, 2011, 1:12 PM MDT for 7 counties in Utah. It was in force for 48 min. 12 reports came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- Apr 21, 2011, 1:12 PM MDT (19:12 UTC)
- Expired
- Apr 21, 2011, 2:00 PM MDT
- In force
- 48 min
- Issued by
- NWS Salt Lake City, UT
- Area
- Storm-based polygon
Counties Box Elder County, UT, Cache County, UT, Davis County, UT, Morgan County, UT, Salt Lake County, UT, Tooele County, UT, Weber County, UT
The radar
The Salt Lake City radar (KMTX), 39 km from the middle of the area, began a volume at 19:13 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Apr 21, 1:14 PM MDT | TSTM WND GST 67 | 2 W Salt Lake City, UT | SALT LAKE CITY AIRPORT SENSOR |
| Apr 21, 1:15 PM MDT | TSTM WND DMG | Slc Intl Arpt, UT | LIGHT POLE FELL ON 2 CARS AT SALT LAKE INTERNATIONAL AIRPORT |
| Apr 21, 1:20 PM MDT | TSTM WND DMG | Ogden, UT | MULTIPLE TREES DOWN IN THE OGDEN AREA. |
| Apr 21, 1:20 PM MDT | TSTM WND DMG | Pleasant View, UT | MULTIPLE TREES DOWN. POWERLINES REPORTED DOWN ACROSS THE COUNTY. |
| Apr 21, 1:20 PM MDT | TSTM WND GST 62 | 5 Sw West Valley City, UT | BACCUS SENSOR |
| Apr 21, 1:25 PM MDT | TSTM WND DMG | 2 Wnw Salt Lake City, UT | LARGE TREES DOWN IN ROSE PARK |
| Apr 21, 1:26 PM MDT | TSTM WND DMG | Woods Cross, UT | A PARKED SMALL PRIVATELY OWNED AIR PLANE WAS FLIPPED OVER BY THE STRONG WINDS AT THE BOUNTIFUL AIRPORT. |
| Apr 21, 1:30 PM MDT | TSTM WND DMG | 1 N Salt Lake City, UT | 18-24 INCH DIAMETER TREE SNAPPED AND LANDED ON HOUSE CAUSING MINOR ROOF DAMAGE IN THE AVENUES |
| Apr 21, 1:30 PM MDT | TSTM WND DMG | Huntsville, UT | AT LEAST TWO DOZEN LARGE TREES DOWN IN HUNTSVILLE. SEVERAL OF THE DOWN TREES DAMAGED STRUCTURES WITH ONE HOUSE WITH MODERATE DAMAGE. MANY POWERLINES DOWN. |
| Apr 21, 1:30 PM MDT | TSTM WND GST 62 | 5 Ne Holladay, UT | PARLEYS CANYON AT QUARRY, UT - UTQRY |
| Apr 21, 1:30 PM MDT | TSTM WND GST 104 | 5 Ese Ogden, UT | ODGEN PEAK - OGP 9570 FT |
| Apr 21, 2:02 PM MDT | TSTM WND DMG | 1 Wsw Salt Lake City, UT | SEMI TRUCK BLOWN OVER |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Salt Lake City I, UT (KSLC), launched 12:00Z, 7.2 hours before the alert went out and 71 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.
- Mixed-layer CAPE
- 411 J/kg
- Mixed-layer CIN
- -62 J/kg
- Mixed-layer LCL
- 1122 m above ground
- 0-6 km bulk shear
- 60 kt
- 0-1 km storm-relative helicity
- 87 m²/s²
- 0-3 km storm-relative helicity
- 138 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -1.2
The text
As transmitted, in the capitals the NWS used until 2016.
160
WUUS55 KSLC 211912
SVRSLC
UTC003-005-011-029-035-045-057-212000-
/O.NEW.KSLC.SV.W.0009.110421T1912Z-110421T2000Z/
BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
112 PM MDT THU APR 21 2011
THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR...
NORTHEASTERN BOX ELDER COUNTY IN UTAH
WESTERN CACHE COUNTY IN UTAH
DAVIS COUNTY IN UTAH
WESTERN MORGAN COUNTY IN UTAH
NORTHERN SALT LAKE COUNTY IN UTAH
EAST CENTRAL TOOELE COUNTY IN UTAH
WEBER COUNTY IN UTAH
* UNTIL 200 PM MDT
* AT 108 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. THESE STORMS WERE
LOCATED ALONG A LINE EXTENDING FROM 6 MILES NORTH OF HOWELL TO
WARREN TO STANSBURY PARK...MOVING EAST AT 35 MPH.
* LOCATIONS IN THE WARNING INCLUDE...
HOOPER... THATCHER... PLAIN CITY... WEST WEBER... WEST POINT...
BOTHWELL... FARR WEST... SLATERVILLE... CLINTON... SYRACUSE...
WILSON... WEST HAVEN... PLEASANT VIEW... WILLARD AND CORINNE
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.
WIND GUSTS TO 70 MPH HAVE BEEN REPORTED WITH THIS LINE OF
THUNDERSTORMS.
&&
LAT...LON 4142 11156 4069 11171 4057 11245 4126 11223
4192 11259 4202 11216 4201 11191
TIME...MOT...LOC 1911Z 253DEG 32KT 4187 11242 4129 11211
4066 11227
$$
CRK2 follow-up statements
929
WWUS55 KSLC 211918
SVSSLC
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
118 PM MDT THU APR 21 2011
UTC003-005-011-029-035-045-057-212000-
/O.CON.KSLC.SV.W.0009.000000T0000Z-110421T2000Z/
TOOELE UT-BOX ELDER UT-SALT LAKE UT-WEBER UT-DAVIS UT-CACHE UT-
MORGAN UT-
118 PM MDT THU APR 21 2011
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 200 PM MDT
FOR WESTERN MORGAN...WESTERN CACHE...EASTERN DAVIS...CENTRAL WEBER...
NORTHERN SALT LAKE...NORTHEASTERN BOX ELDER AND EAST CENTRAL TOOELE
COUNTIES...
AT 117 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER
SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. THESE STORMS
WERE LOCATED ALONG A LINE EXTENDING FROM 6 MILES SOUTHWEST OF
WASHAKIE TO SNOWBASIN TO KEARNS...MOVING EAST AT 35 MPH.
* LOCATIONS IN THE WARNING INCLUDE...
WEST VALLEY CITY... TREMONTON... KEARNS... GARLAND... BRIGHAM
CITY... HONEYVILLE... SNOWBASIN... FARMINGTON... PINEVIEW
RESERVOIR... ELWOOD... WOODS CROSS... NORTH SALT LAKE... LIBERTY...
PORTAGE AND DEWEYVILLE
LAT...LON 4142 11156 4069 11171 4059 11232 4122 11212
4195 11246 4202 11216 4201 11191
TIME...MOT...LOC 1918Z 253DEG 32KT 4190 11230 4118 11187
4064 11205
$$
CRK125
WWUS55 KSLC 211928
SVSSLC
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
128 PM MDT THU APR 21 2011
UTC045-211938-
/O.CAN.KSLC.SV.W.0009.000000T0000Z-110421T2000Z/
TOOELE UT-
128 PM MDT THU APR 21 2011
...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL TOOELE COUNTY IS
CANCELLED...
LAT...LON 4201 11191 4142 11156 4069 11171 4061 11219
4123 11201 4197 11236 4202 11217
TIME...MOT...LOC 1928Z 253DEG 32KT 4193 11218 4120 11176
4066 11194
$$
UTC003-005-011-029-035-057-212000-
/O.CON.KSLC.SV.W.0009.000000T0000Z-110421T2000Z/
BOX ELDER UT-SALT LAKE UT-WEBER UT-DAVIS UT-CACHE UT-MORGAN UT-
128 PM MDT THU APR 21 2011
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 200 PM MDT
FOR WESTERN MORGAN...WESTERN CACHE...EASTERN DAVIS...CENTRAL WEBER...
NORTHERN SALT LAKE AND NORTHEASTERN BOX ELDER COUNTIES...
AT 126 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER
SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. THESE STORMS
WERE LOCATED ALONG A LINE EXTENDING FROM WASHAKIE TO SNOWBASIN TO
TAYLORSVILLE...MOVING EAST AT 35 MPH.
A WIND GUST TO 67 MPH WAS REPORTED AT THE SALT LAKE CITY AIRPORT
WITH THIS LINE OF THUNDERSTORMS.
* LOCATIONS IN THE WARNING INCLUDE...
BOUNTIFUL... COLLINSTON... TAYLORSVILLE... PLYMOUTH...
HUNTSVILLE... SALT LAKE CITY... SOUTH SALT LAKE... PETERSON...
NORDIC VALLEY... SUGARHOUSE... MENDON... WELLSVILLE... UNIVERSITY
OF UTAH... POWDER MOUNTAIN AND HOLLADAY
LAT...LON 4201 11191 4142 11156 4069 11171 4061 11219
4123 11201 4197 11236 4202 11217
TIME...MOT...LOC 1928Z 253DEG 32KT 4193 11218 4120 11176
4066 11194
$$
CRKThe office that day
Everything else NWS Salt Lake City, UT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 21, 10:41 AM MDT | Wind Advisory | SLC | 10 hr | |
| Apr 21, 11:03 AM MDT | Special Weather Statement | SLC | Tooele | 57 min |
| Apr 21, 11:12 AM MDT | Severe Thunderstorm Warning | SLC | Box Elder, Tooele | 48 min |
| Apr 21, 11:39 AM MDT | Special Weather Statement | SLC | Rich | 51 min |
| Apr 21, 11:55 AM MDT | Special Weather Statement | SLC | Tooele | 50 min |
| Apr 21, 12:12 PM MDT | Severe Thunderstorm Warning | SLC | Box Elder, Tooele | 48 min |
| Apr 21, 12:25 PM MDT | High Wind Warning | SLC | 6 hr | |
| Apr 21, 12:29 PM MDT | Severe Thunderstorm Warning | SLC | Box Elder | 46 min |
| Apr 21, 12:33 PM MDT | Special Weather Statement | SLC | Rich | 27 min |
| Apr 21, 12:37 PM MDT | Severe Thunderstorm Warning | SLC | Juab, Tooele | 23 min |
| Apr 21, 12:43 PM MDT | Severe Thunderstorm Warning | SLC | Davis, Weber | 17 min |
| Apr 21, 12:52 PM MDT | Severe Thunderstorm Warning | SLC | Box Elder, Cache, Davis, Morgan, Tooele, Weber | 23 min |
| Apr 21, 12:55 PM MDT | Severe Thunderstorm Warning | SLC | Juab, Morgan, Salt Lake, Tooele, Utah | 35 min |
| Apr 21, 1:24 PM MDT | Severe Thunderstorm Warning | SLC | Juab, Salt Lake, Tooele, Utah | 36 min |
| Apr 21, 1:45 PM MDT | Severe Thunderstorm Warning | SLC | Box Elder, Cache, Davis, Morgan, Rich, Salt Lake and 3 more | 30 min |
| Apr 21, 1:55 PM MDT | Special Weather Statement | SLC | Utah, Wasatch | 50 min |
| Apr 21, 2:10 PM MDT | Special Weather Statement | SLC | Carbon | 50 min |
| Apr 21, 2:14 PM MDT | Severe Thunderstorm Warning | SLC | Cache, Morgan, Rich, Summit | 46 min |
| Apr 21, 2:16 PM MDT | Severe Thunderstorm Warning | SLC | Carbon | 29 min |
| Apr 21, 2:41 PM MDT | Severe Thunderstorm Warning | SLC | Rich | 35 min |
| Apr 21, 2:44 PM MDT | Severe Thunderstorm Warning | SLC | Carbon | 16 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.