Alert archive / Arizona / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 94, NWS Tucson, AZ

September 1, 1997Pima County, Arizona

NWS Tucson, AZ issued this severe thunderstorm warning at Sep 1, 1997, 2:04 PM MST for Pima County, Arizona. It was in force for 46 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 1, 1997, 2:04 PM MST (21:04 UTC)
Expired: Sep 1, 1997, 2:50 PM MST
In force: 46 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 21:05 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 12:00Z, 9.1 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: 91 J/kg
Mixed-layer CIN: -191 J/kg
Mixed-layer LCL: 1989 m above ground
0-6 km bulk shear: 16 kt
0-1 km storm-relative helicity: 2 m²/s²
0-3 km storm-relative helicity: 20 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 
TTAA00 KTUS 012105 RRA
SVRTUS
AZC019-012150-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TUCSON AZ
204 PM MST MON SEP 1 1997

THE NATIONAL WEATHER SERVICE IN TUCSON AZ HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 250 PM MST
FOR PEOPLE IN THE FOLLOWING LOCATION...

IN SOUTHERN ARIZONA

   ...EASTERN PIMA COUNTY
 
AT 202 PM MST...TUCSON DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM
3 MILES SOUTH SOUTHEAST OF GREEN VALLEY MOVING NORTHWEST AT 20 MPH.

SOME LOCATIONS IN THE PATH OF THIS STORM ARE...
GREEN VALLEY            BY 204 PM MST
SAHUARITA               BY 211 PM MST


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 Sep 1, 9:50 AM MST, 4 hours 14 minutes earlier.

Area forecast discussion, Sep 1, 9:50 AM MST, 4 hours 14 minutes before

SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
945 AM MST MON SEP 1 1997

A NUMBER OF INTERESTING FACTORS TO CONSIDER THIS MRNG. DEBRIS
CLDS AND EMBEDDED SHRA/TS ONCE AGAIN ACRS THE FCST AREA. THIS
TIME THEY ARE OVR THE WRN ZNS. A VORT MAX WAS MOVING INTO NRN
BAJA AT 16Z WITH ANOTHER SYS ASSOCD WITH A DYING MCS IN THE SRN
GULF OF CA. DYNAMICS WITH BAJA VORT WL RUN INTO THE DEBRIS CLDS
SO NOT SURE HOW MUCH IT WL ENCHANCE AFTN/EVE CONVECTION IN ZN26.

FURTHER E...STG SUBSIDENCE AND MID LVL DRYG EVIDENT ON WV IMAGERY
AND 12Z H7 PLOT. 12Z EPZ SNDG NOT AS DRY AS LAST NGT...BUT PW
STILL BLO 1.00 INCH. APPEARS THAT THE MOVMNT OF THIS AIR MASS IS
TO THE NNW AND WL GIVE THE ERN ZNS A GLANCING BLOW. WL HAVE TO
WATCH DUG DEW PTS AND CU DVLPMNT THIS AFTN TO SEE HOW MUCH THE
DRY AIR HAS INTRUDED.

ALL THIS BEING SAID...BELIEVE THE BEST AREA FOR STG CONVECTION
IN THE TUS CWA THIS AFTN WL BE SANTA CRUZ AND CNTRL PIMA
COUNTIES. THIS AREA WL SEE SEVERAL HRS OF CLRG BEFORE THE AFTN
HRS AND WL RMN FAIRLY CLOSE TO THE DP MSTR BNDRY. TUS METRO AREA
WL ONCE AGAIN BE ON THE ERN EDGE OF THE STGST ACTIVITY.

HI ALF TO MOV N INTO ERN CO TUE. FLOW ALF BEGINS TO VEER AND
SHOULD GIVE AT LEAST THE ERN ZNS A BREAK FM THE NON STOP STREAM
OF TROP MSTR. TUS 333. OKULSKI

TUS...NONE

In the hours before

Special weather statement, Sep 1, 11:43 AM MST, 2 hours 21 minutes before

AZZ019-026>030-012300-
SPECIAL WEATHER STATEMENT...SOUTHEAST ARIZONA CONVECTIVE OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1145 AM MST MON SEP 1 1997...THIS PRODUCT IS NOT UPDATED

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

COCHISE          25          10          25         10     NW 12
GRAHAM           25          10          25         10     NW 12
GREENLEE         30          10          25         10     NW 12
TUCSON/ERN PIMA  30          20          40         20     NW 15
TOHONO OODHAM   35          20          45         25     NW 15
WESTERN PIMA     40          20          45         25     NW 15
SOUTHEAST PINAL  30          20          40         20     NW 15
SANTA CRUZ       40          25          45         25     NW 15

SYNOPSIS...MOISTURE CONTINUES TO STREAM UP FROM MEXICO INTO
SOUTHWESTERN ARIZONA. SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS WILL CONTINUE INTO THE AFTERNOON AND EVENING HOURS
ACROSS WESTERN PIMA COUNTY. SKIES HAVE CLEARED IN SOUTHEAST
ARIZONA AT MIDDAY. DRIER AIR HAS MOVED INTO EASTERN COCHISE AND
GRAHAM COUNTIES FOR LESS THUNDERSTORM ACTIVITY. SANTA CRUZ AND
CENTRAL PIMA COUNTIES WILL SEE THE BEST CHANCE FOR STRONG
THUNDERSTORMS THIS AFTERNOON AND EVENING WITH HEAVY RAIN AND
STRONG GUSTY WINDS.

*****************************************************************
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/OKULSKI

The office that day

Everything else NWS Tucson, AZ issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 1, 2:44 PM MST	Severe Thunderstorm Warning	TWC	Pima	46 min
Sep 1, 3:37 PM MST	Severe Thunderstorm Warning	TWC	Pima	2 hr

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.