Alert archive / Arizona / Severe Thunderstorm Warnings in 1998
Severe Thunderstorm Warning 71, NWS Tucson, AZ
NWS Tucson, AZ issued this severe thunderstorm warning at Aug 21, 1998, 7:01 PM MST for Pima County, Arizona. It was in force for 34 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
- Aug 21, 1998, 7:01 PM MST (02:01 UTC)
- Expired
- Aug 21, 1998, 7:35 PM MST
- In force
- 34 min
- Issued by
- NWS Tucson, AZ
- Area
- Whole counties
County Pima County, AZ
The radar
The Tucson radar (KEMX), 112 km from the middle of the area, began a volume at 02:05 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
Tuscon, AZ (KTUS), launched 00:00Z, 2.0 hours before the alert went out and 84 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
- 18 J/kg
- Mixed-layer CIN
- -29 J/kg
- Mixed-layer LCL
- 3025 m above ground
- 0-6 km bulk shear
- 11 kt
- 0-1 km storm-relative helicity
- -19 m²/s²
- 0-3 km storm-relative helicity
- -8 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KTUS 220201 RRA SVRTUS AZC019-220235- BULLETIN - EAS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE TUCSON AZ 701 PM MST FRI AUG 21 1998 THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... NEAR KITT PEAK EAST CENTRAL PIMA COUNTY IN SOUTHERN ARIZONA * UNTIL 735 PM MST * AT 700 PM MST... DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 24 MILES EAST OF SELLS OR 9 MILES SOUTHEAST OF KIT PEAK MOVINGj WEST AT 15 MPH. * THE SEVERE THUNDERSTORM WILL BE NEAR... KIT PEAK BY 713 PM MST JRG
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.
NWS Tucson, AZ wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 21, 2:30 PM MST, 4 hours 31 minutes earlier.
Area forecast discussion, Aug 21, 2:30 PM MST, 4 hours 31 minutes before
SOUTHEAST ARIZONA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TUCSON AZ 230 PM MST FRI AUG 21 1998 SYNOPSIS...MOISTURE HAS RETURNED TO SOUTHEAST ARIZONA. SCATTERED THUNDERSTORMS THIS EVENING WILL BE FOLLOWED BY A LITTLE LESS ACTIVITY SATURDAY AS CONDITIONS OUT AHEAD OF AN EASTERLY DISTURBANCE MOVING IN FROM TEXAS BRIEFLY STABLIZES THE ATMOSPHERE. THIS SAME DISTURBANCE WILL MOVE IN ALONG WITH EVEN MORE MOISTURE SUNDAY FOR ANOTHER STRONG THUNDERSTORM DAY FOLLOWED BY SCATTERED THUNDERSTORMS TO START THE WORK WEEK. DISCUSSION...AGAIN A DECAYING CLOUD SHIELD TO DEAL WITH...EDGES DISSIPATING MORE SLOWLY TODAY WITH SOME THUNDERSTORM DEVELOPMENT FINALLY UNDERWAY. GOING TO NEED A FEW MORE DEGREES TO REALLY GET GOING IN SANTA CRUZ VALLEY AND I JUST DONT HAVE A GOOD FEEL FOR THE NEXT 6 HOURS. ILL GO AHEAD AND KNOCK A FEW PERCENT OFF THE POPS AND MENTION CONDITIONAL PROBABILITIES RATHER THAN AREAL COVERAGE. HEAVY RAINFALL STILL A POTENTIAL CONCERN. WESTERN AREAS MAY SEE INTERESTING DEVELOPMENT WITH RATHER STRONG STORMS POSSIBLE NEAR THE TIGHT MOISTURE GRADIENT CREATED BY A DRIER SOUTHWESTERLY FLOW IN WESTERN ARIZONA. VERY CLEAR EASTERLY DISTURBANCE SHOWING UP ON WATER VAPOR IMAGERY MOVING THROUGH WEST TEXAS TOWARD NORTHERN MEXICO. BRIEF DRYING WITH SUBSIDENCE WRAPPING AHEAD OF THIS FEATURE TO INHIBIT THUNDERSTORM DEVELOPMENT DURING THE DAY SATURDAY...BUT JUST THE OPPOSITE FOR SUNDAY AS THE FEATURE NEARS SOUTHEAST ARIZONA. MEYER 3235. .TWC...NONE.
In the hours before
Local storm report, Aug 21, 5:54 PM MST, 1 hour 7 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TUCSON ARIZONA
554 PM MST FRI AUG 21 1998
TIME(MST) .....CITY LOCATION..... STATE ...EVENT/REMARKS...
....COUNTY LOCATION....
0534 PM GREEN VLY AZ 60 MPH TSTM GUST
08/21/98 PIMA TREES DOWNEDNearby
Severe Thunderstorm Warnings in Arizona, 1998Every severe thunderstorm warning in 1998
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.