Alert archive / Utah / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 116, NWS Salt Lake City, UT
NWS Salt Lake City, UT issued this severe thunderstorm warning at Sep 20, 1997, 4:43 PM MDT for San Juan County, Utah. It was in force for 62 min. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Sep 20, 1997, 4:43 PM MDT (22:43 UTC)
- Expired
- Sep 20, 1997, 5:45 PM MDT
- In force
- 62 min
- Issued by
- NWS Salt Lake City, UT
- Area
- Whole counties
County San Juan County, UT
The radar
The Grand Junction radar (KGJX), 212 km from the middle of the area, began a volume at 22:47 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
Grand Junction, CO (KGJT), launched 12:00Z, 10.7 hours before the alert went out and 202 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
- 197 J/kg
- Mixed-layer CIN
- -94 J/kg
- Mixed-layer LCL
- 696 m above ground
- 0-6 km bulk shear
- 64 kt
- 0-1 km storm-relative helicity
- 121 m²/s²
- 0-3 km storm-relative helicity
- 209 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 1.6
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KSLC 202245 RRA SVRSLC UTC037-202345- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE SALT LAKE CITY UT 443 PM MDT SAT SEP 20 1997 THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY UT HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 545 PM MDT FOR PEOPLE IN THE FOLLOWING LOCATION... IN SOUTHEASTERN UTAH ...NORTHERN SAN JUAN COUNTY AT 439 PM MDT...A SEVERE THUNDERSTORM WAS INDICATED BY DOPPLER RADAR 31 MILES NORTHWEST OF MONTICELLO OR 25 MILES WEST OF LA SAL MOVING NORTHEAST AT 40 MPH. HEAVY RAINFALL...FREQUENT LIGHTNING...LARGE HAIL...AND STRONG GUSTY WINDS IN EXCESS OF 57 MPH ARE POSSIBLE WITH THIS STORM. THIS STORM IS EXPECTED TO MOVE OVER THE CANYONLANDS NATIONAL PARK AREA WITHIN THE NEXT HOUR. WHEN THUNDERSTORMS ARE OCCURRING...PEOPLE SHOULD MOVE INSIDE A STRONG BUILDING. DO NOT STAND BY WINDOWS. DO NOT USE TELEPHONES OR ELECTRICAL APPLIANCES UNLESS IN AN EMERGENCY UNTIL THE STORM HAS PASSED. MOTORISTS SHOULD NOT DRIVE INTO LOW WATER CROSSINGS.
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 20, 1:50 PM MDT, 2 hours 53 minutes before
UTZ009>013-018-021>027-210100- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SALT LAKE CITY UT 150 PM MDT SAT SEP 20 1997 ...CONDITIONS FAVORABLE FOR LARGE HAIL AND MICROBURST WINDS WITH THUNDERSTORMS THIS AFTERNOON AND EVENING IN EASTERN UTAH... SCATTERED THUNDERSTORMS CONTINUE TO DEVELOP OVER EASTERN UTAH THIS AFTERNOON AND ARE EXPECTED TO CONTINUE INTO THE EVENING. CONDITIONS ARE FAVORABLE FOR SOME OF THESE STORMS TO BE ACCOMPANIED BY STRONG GUSTY WINDS...FREQUENT LIGHTNING...AND LARGE HAIL. WIND GUSTS IN EXCESS OF 50 MPH OR MORE AND LARGE HAIL IN EXCESS OF 1 1/2 INCHES ARE POSSIBLE. IF YOU ARE PLANNING OUTDOOR ACTIVITIES SUCH AS PICNICKING OR CAMPING, BE ALERT FOR RAPIDLY DETERIORATING WEATHER CONDITIONS. PEOPLE SHOULD BE ALERT FOR THE POSSIBILITY OF THESE STRONG WINDS AND LARGE HAIL. TAKE PRECAUTIONS TO TIE DOWN LOOSE OBJECTS THAT CAN BECOME AIRBORNE IN STRONG THUNDERSTORM WINDS OR BRING THEM INDOORS. BOATERS SHOULD WATCH THE WEATHER CLOSELY AND MOVE TO SAFE HARBOR IF THUNDERSTORMS THREATEN AS STRONG WINDS COULD CAUSE VERY ROUGH WATER. JN...1950Z
Special weather statement, Sep 20, 1:53 PM MDT, 2 hours 50 minutes before
UTZ009>013-018-021>027-210100- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SALT LAKE CITY UT 150 PM MDT SAT SEP 20 1997 ...CONDITIONS FAVORABLE FOR LARGE HAIL AND MICROBURST WINDS WITH THUNDERSTORMS THIS AFTERNOON AND EVENING IN EASTERN UTAH... SCATTERED THUNDERSTORMS CONTINUE TO DEVELOP OVER EASTERN UTAH THIS AFTERNOON AND ARE EXPECTED TO CONTINUE INTO THE EVENING. CONDITIONS ARE FAVORABLE FOR SOME OF THESE STORMS TO BE ACCOMPANIED BY STRONG GUSTY WINDS...FREQUENT LIGHTNING...AND LARGE HAIL. WIND GUSTS IN EXCESS OF 50 MPH OR MORE AND LARGE HAIL IN EXCESS OF 1 1/2 INCHES ARE POSSIBLE. IF YOU ARE PLANNING OUTDOOR ACTIVITIES SUCH AS PICNICKING OR CAMPING, BE ALERT FOR RAPIDLY DETERIORATING WEATHER CONDITIONS. PEOPLE SHOULD BE ALERT FOR THE POSSIBILITY OF THESE STRONG WINDS AND LARGE HAIL. TAKE PRECAUTIONS TO TIE DOWN LOOSE OBJECTS THAT CAN BECOME AIRBORNE IN STRONG THUNDERSTORM WINDS OR BRING THEM INDOORS. BOATVERS SHOULD WATCH THE WEATHER CLOSELY AND MOVE TO SAFE HARBOR IF THUNDERSTORMS THREATEN AS STRONG WINDS COULD CAUSE VERY ROUGH WATER. JN...1950Z
Nearby
Severe Thunderstorm Warnings in Utah, 1997Every severe thunderstorm warning in 1997
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.