Alert archive / Arizona / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 84, NWS Tucson, AZ

August 27, 1997Pima County, Arizona

NWS Tucson, AZ issued this severe thunderstorm warning at Aug 27, 1997, 4:30 PM MST for Pima County, Arizona. It was in force for 50 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 27, 1997, 4:30 PM MST (23:30 UTC)
Expired: Aug 27, 1997, 5:20 PM MST
In force: 50 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 23:31 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 12:00Z, 11.5 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 247 J/kg
Mixed-layer CIN: -237 J/kg
Mixed-layer LCL: 1861 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: -49 m²/s²
0-3 km storm-relative helicity: 44 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.4

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KTUS 272330 RRA
SVRTUS
AZC019-280020-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TUCSON AZ
430 PM MST WED AUG 27 1997

THE NATIONAL WEATHER SERVICE IN TUCSON AZ HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 520 PM MST
FOR PEOPLE IN THE FOLLOWING LOCATION...

IN SOUTHERN ARIZONA

   ...SOUTH CENTRAL PIMA COUNTY
 
AT 428 PM MST...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 16
MILES SOUTHEAST OF SELLS OR 9 MILES NORTH NORTHEAST OF SAN MIGUEL
MOVING NORTHWEST AT 5 MPH. THIS STORM WAS CAPABLE OF PRODUCING WIND
GUSTS TO 65 MPH AND ONE INCH DIAMETER HAIL.

OKULSKI

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 27, 2:30 PM MST, 2 hours earlier.

Area forecast discussion, Aug 27, 2:30 PM MST, 2 hours before

SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
230 PM MST WED AUG 27 1997

SEVERAL INTERESTING THINGS GOING ON THIS AFTERNOON. GULF SURGE IN
PROGRESS...AND HAS BEEN FOR LAST 24 HOURS OR SO. UPPER LOW OVER
SOUTHERN GULF HAS NOT DECIDED TO MOVE NORTH YET...AND SINCE
MODELS DONT HANDLE THIS SORT OF THING WELL WE WILL HAVE TO WAIT
AND SEE WHAT IT DOES. THE MAIN TREND OVER THE NEXT COUPLE OF DAYS
IS FOR THE MOISTURE TO SHIFT EAST AND TO SEE SOME DRYING FROM THE
WEST. WITH STEEP LAPSE RATES FROM TUCSON EASTWARD...ANY MOISTURE
THAT ADVECTS OVER THE AREA COULD SET OFF A TSTORM OR TWO EVEN IN
THE MIDDLE OF THE NIGHT. LOOKS LIKE THURSDAY WILL BE MORE ACTIVE
THAN TODAY AS MOISTURE AND HEATING WILL BOTH BE THERE. THE TREND
IS TOWARD THE STANDARD MONSOON FORECAST ON FRIDAY. TUS 2333.
LUDWIG

TUS...NONE

In the hours before

Special weather statement, Aug 27, 11:49 AM MST, 4 hours 41 minutes before

AZZ019-026>030-272300-
SPECIAL WEATHER STATEMENT...SOUTHEAST ARIZONA CONVECTIVE OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1145 AM MST WED AUG 27 1997...THIS PRODUCT IS NOT UPDATED

                AREAL    PROBABILITY   RAIN GREATER THAN   STORM
              COVERAGE    OF SEVERE     1.00       2.00    MOTION

COCHISE          10          30          10          0     NW  10
GRAHAM           10          30          10          0     NW  10
GREENLEE         20          30          20          0     NW  10
TUCSON/ERN PIMA  20          40          30         10     N   10
TOHONO OODHAM   30          20          60         20     N   10
WESTERN PIMA     30          20          70         30     N   10
SOUTHEAST PINAL  20          30          30         10     N   10
SANTA CRUZ       20          30          30         10     N   10

SYNOPSIS...A DISTINCT MOISTURE BOUNDRY EXISTS ACROSS THE AREA
TODAY. THE DRIER AIR IS GENERALLY FROM TUCSON EASTWARD WITH VERY
MOIST AIR TO THE WEST. THE MAIN THREAT FROM STORMS THAT FORM IN
THE DRIER AIR TO THE EAST WOULD BE STRONG GUSTY WINDS WHILE HEAVY
RAIN WILL BE THE PRIMARY THREAT FROM STORMS IN THE WEST.

*****************************************************************
KEY...
AREAL COVERAGE - PERCENT OF COUNTY OR AREA THAT WILL EXPERIENCE
                  THUNDERSTORMS
PROB OF SEVERE - THE PROBABILITY THAT ANY ONE OF THE STORMS WILL
                  REACH SEVERE LEVELS (DAMAGING WIND AND/OR
                  LARGE HAIL)
RAIN GRTR THAN - THE PROBABILITY THAT ANY ONE OF THE STORMS WILL
                  PRODUCE RAIN EXCEEDING 1 INCH OR 2 INCHES IN
                  ANY LOCATION
STORM MOTION   - GENERAL DIRECTION TO WHICH THE STORMS WILL
                  LIKELY MOVE AND SPEED IN MPH

NOTE...
VALID TIME IS FROM 12 NOON TO 12 MIDNIGHT OF THE DAY OF ISSUANCE

THIS PRODUCT IS NOT TO BE USED IN PLACE OF SEVERE THUNDERSTORM OR
FLASH FLOOD WARNINGS OR WATCHES. THIS PRODUCT IS ONLY USED FOR
OUTLOOK PURPOSES.

END/LUDWIG

Nearby

Severe Thunderstorm Warnings in Arizona, 1997 Every 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.