Alert archive / Utah / Severe Thunderstorm Warnings in 1986

Severe Thunderstorm Warning 9, NWS Salt Lake City, UT

September 9, 1986Davis County, Salt Lake County, Tooele County, Utah

NWS Salt Lake City, UT issued this severe thunderstorm warning at Sep 9, 1986, 10:59 AM MDT for Davis County, Salt Lake County, Tooele County, Utah. It was in force for 2 hr.

The area

The counties it named.

The facts

Issued
Sep 9, 1986, 10:59 AM MDT (16:59 UTC)
Expired
Sep 9, 1986, 1:00 PM MDT
In force
2 hr
Issued by
NWS Salt Lake City, UT
Area
Whole counties

Counties Davis County, UT, Salt Lake County, UT, Tooele 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

Salt Lake City I, UT (KSLC), launched 12:00Z, 5.0 hours before the alert went out and 42 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 1986-09-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 80 joules per kilogram.LCLLFCEL10008507005003002001001 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, Salt Lake City I, UT at 12:00Z on 1986-09-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 20 square meters per square second.1939587897Sfc1 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
80 J/kg
Mixed-layer CIN
-213 J/kg
Mixed-layer LCL
1829 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
20 m²/s²
0-3 km storm-relative helicity
127 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 
TTAAOO KSLC 091659
SVRSLC
UTC011-035-057-003-045-091900-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1059 AM MDT TUE SEP  9 1986
 
THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING
EFFECTIVE UNTIL 100 PM MDT FOR PEOPLE IN THE FOLLOWING COUNTIES:
 
IN NORTH CENTRAL UTAH
          ..DAVIS..SALT LAKE..WEBER
IN NORTHWEST UTAH
          ..EASTERN BOX ELDER..NORTHEASTERN TOOELE

MILITARY PERSONNEL AT EAGLE RANGE REPORTED 3/4 TO 1 INCH DIAMETER
HAIL JUST BEFORE 1100 AM MDT. EAGLE RANGE IS ALONG THE WESTERN SHORES
OF THE GREAT SALT LAKE.
 
THIS LINE OF THUNDERSTORMS IS EXPECTED TO MOVE INTO THE WASATCH FRONT
DURING THE NEXT TWO HOURS. IT WILL BE ACCOMPANIED BY STRONG GUSTING
WINDS IN EXCESS OF 55 MPH.. POSSIBLE LARGE HAIL AND BRIEF HEAVY RAIN.
IF YOU ARE CAUGHT OUTSIDE, SEEK SHELTER FROM THE WEATHER IN A
STRONG BUILDING.  DAMAGING WIND, LARGE HAIL, BVERY HEAVY RAIN, AND
DEADLY LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS.  STAY
INSIDE AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED.

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, Sep 9, 6:04 AM MDT, 4 hours 55 minutes before
SPECIAL WEATHER STATEMENT AND UTAH WEATHER SUMMARY
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
600 AM MDT TUE SEP 9 1986

   TASTE OF AUTUMN..ANYONE??

AN UNSEASONABLY COLD LATE SUMMER TROUGH CENTERED OVER THE COLUMBIA
RIVER BASIN OF OREGON AND WASHINGTON IS STILL HEADED TOWARDS UTAH.
THE MAIN BATCH OF COLD AIR IS HAVING TROUBLE GETTING ORGANIZED
IN SOUTHEAST OREGON AND NORTHWEST NEVADA BUT SHOULD GET ITS ACT
TOGETHER DURING THIS MORNING. A COLD FRONT IS EXPECTED TO PASS
THROUGH THE WASATCH FRONT DURING THE AFTERNOON AND THE REMAINDER
OF THE STATE DURING TONIGHT.

MUCH COLDER AIR WILL FOLLOW WITH A PERIOD OF RAIN TONIGHT INTO
EARLY WEDNESDAY. THE SNOW LEVEL WILL BE LOWERING ALSO..GIVING
MUCH OF THE HIGH COUNTY IN NORTHERN UTAH ITS FIRST SNOW OF THE
SEASON. THE MAIN SNOW LEVEL SHOULD HOLD ABOUT 8000FT AND A FEW
INCHES OF ACCUMULATION IS LIKELY ABOVE THAT ZONE. THIS MEANS MOST
OF THE HIGH UINTA LAKES AS WELL AS STRAWBERRY RESERVOIR WILL
GET AN EARLY DEPOSIT OF SNOW.

THE GUSTY SOUTH WINDS OF MONDAY AFTERNOON MAY REAPPEAR TO SOME
EXTENT TODAY ESPECIALLY IN THE SOUTHWEST VALLEYS. GUSTY WINDS FROM
THE NORTHWEST SHOULD ACCOMPANY THE FRONTAL PASSAGE IN SOME AREAS
ALONG WITH INCREASING SHOWERS AND THUNDERSHOWERS.

AROUND THE STATE THIS MORNING..A BAND OF SHOWERS LINGERS OVER THE
EXTREME NORTHWEST WITH A FEW LIGHT SPRINKLES REPORTED. A FEW
SHOWERS OR THUNDERSHOWERS ARE ALSO IN PROGRESS ACROSS THE SOUTHEAST
SECTION AND WILL LIKE)LY INCREASE AS THE DAY WEARS ON. TEMPERATURES
JUST BEFORE DAWN ARE IN THE 50S AND 60S.

KML...1200Z

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 9, 10:59 AM MDTSevere Thunderstorm WarningSLCBox Elder, Weber2 hr
Sep 9, 12:05 PM MDTTornado WarningSLCDavis, Weber55 min
Sep 9, 3:55 PM MDTFlash Flood WarningSLCSan Juan2 hr

Nearby

Severe Thunderstorm Warnings in Utah, 1986Every severe thunderstorm warning in 1986

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.