Alert archive / Utah / Severe Thunderstorm Warnings in 1987
Severe Thunderstorm Warning 6, NWS Salt Lake City, UT
NWS Salt Lake City, UT issued this severe thunderstorm warning at Jul 21, 1987, 12:50 PM MDT for Summit County, Utah. It was in force for 40 min. 1 report came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- Jul 21, 1987, 12:50 PM MDT (18:50 UTC)
- Expired
- Jul 21, 1987, 1:30 PM MDT
- In force
- 40 min
- Issued by
- NWS Salt Lake City, UT
- Area
- Whole counties
County Summit County, UT
The radar
The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 21, 1:30 PM MDT | Hail 1.5 | Summit, UT |
NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.
The nearest sounding before it
Salt Lake City I, UT (KSLC), launched 12:00Z, 6.8 hours before the alert went out and 80 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
- 31 J/kg
- Mixed-layer CIN
- -185 J/kg
- Mixed-layer LCL
- 859 m above ground
- 0-6 km bulk shear
- 66 kt
- 0-1 km storm-relative helicity
- 63 m²/s²
- 0-3 km storm-relative helicity
- 351 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.
What forecasters said that day
The local office's own words before this severe thunderstorm 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 21, 10:04 AM MDT, 2 hours 46 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY
1000 AM MDT TUE JUL 21 1987
...MORE THUNDERSTORMS AND WIND...
A HUGE COLD UPPER TROUGH ALONG THE WEST COAST CONTINUES TO CAUSE A
STRONG...MOIST...SOUTHERLY FLOW OF AIR OVER UTAH. THIS IS ALLOWING
SCATTERED SHOWERS AND THUNDERSTORMS AT TIMES WHICH ARE LIKELY TO
CAUSE SOME LOCAL STRONG WINDS AND POSSIBLE HEAVY RAINFALL AND SMALL
HAIL.
ALREADY THIS MORNING PEA SIZED HAIL HAS BEEN REPORTED AT HILL AFB...
OGDEN AND CEDAR CITY. WIND GUSTS TO 35 MPH HAVE ACCOMPANIED SOME OF THE
STORMS. KAYSVILLE HAS RECEIVED .77 INCH OF RAIN NORTH OGDEN .78 AND
.96 AT SNOWBIRD IN THE MOUNTAINS EAST OF SALT LAKE CITY.
DRIER AND MORE STABLE AIR IS EXPECTED TO BEGIN MOVING INTO THE STATE
FROM THE SOUTHWEST LATE TODAY AND TONIGHT. HOWEVER UNTIL THEN PEOPLE
SHOULD BE PREPARED FOR RAIN...LIGHTNING AND POSSIBLE HAIL AT TIMES.
FURTHER STATEMENTS WILL BE ISSUED AS NECESSARY.
DH/DJ/GS 21/1600ZThe office that day
Everything else NWS Salt Lake City, UT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 21, 12:50 PM MDT | Severe Thunderstorm Warning | SLC | Davis, Salt Lake | 40 min |
| Jul 21, 1:38 PM MDT | Severe Thunderstorm Warning | SLC | Utah, Wasatch | 52 min |
| Jul 21, 5:36 PM MDT | Severe Thunderstorm Warning | SLC | Emery, Grand | 54 min |
Nearby
Severe Thunderstorm Warnings in Utah, 1987Every severe thunderstorm warning in 1987
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.