Alert archive / Arizona / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 85, NWS Tucson, AZ

September 9, 1998Pima County, Arizona

NWS Tucson, AZ issued this severe thunderstorm warning at Sep 9, 1998, 4:52 PM MST for Pima County, Arizona. It was in force for 48 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 9, 1998, 4:52 PM MST (23:52 UTC)
Expired
Sep 9, 1998, 5:40 PM MST
In force
48 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 23:54 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, 11.9 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-pSkew-T log-p diagram, Tuscon, AZ at 12:00Z on 1998-09-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 7 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, Tuscon, AZ at 12:00Z on 1998-09-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -3 square meters per square second.1939Sfc1 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
7 J/kg
Mixed-layer CIN
-251 J/kg
Mixed-layer LCL
2806 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
-3 m²/s²
0-3 km storm-relative helicity
33 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 092354 RRA
SVRTUS
AZC019-100040-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TUCSON AZ
452 PM MST WED SEP 9 1998

THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN PIMA COUNTY IN SOUTHERN ARIZONA
  AJO AND ALONG STATE HIGHWAY 85 NORTH WHY

* UNTIL 540 PM MST

* AT 452 PM MST... DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM
  NEAR AJO. THIS STORM WAS MOVING NORTH AT 20 MPH. STRONG WINDS IN
  EXCESS OF 58 MPH ALONG WITH LOCALLY HEAVY RAINFALL CAN BE EXPECTED
  WITH THIS STORM.

* THE SEVERE THUNDERSTORMS WILL BE NEAR...
  AJO  AT 500 PM MST.

JD

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 9, 2:30 PM MST, 2 hours 22 minutes earlier.

Area forecast discussion, Sep 9, 2:30 PM MST, 2 hours 22 minutes before
SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
230 PM MST WED SEP 9 1998

SYNOPSIS...THE CIRCULATION BETWEEN A TROF OF LOW PRESSURE ALONG THE
CALIFORNIA COAST AND A HIGH PRESSURE IN THE MIDWEST WILL RESULT IN
INCREASED MOISTURE FOR ALL OF ARIZONA FOR THE NEXT SEVERAL DAYS.
THIS WILL INCREASZE THE THUNDERSTORM ACTIVITY AND KEEP TEMPERATURES
A LITTLE COOLER.

DISCUSSION...THUNDERSTORMS DEVELOPING AS EXPECTED WITH STRONGEST
STORMS TO DEVELOP OVER FAR WESTERN PIMA COUNTY IN DEEPER MOISTURE
FIELD. CANT RULE OUT NOCTURNAL STORMS...AND AS LONG AS TROF STAYS TO
THE WEST ADVECTION OF MOISTURE WILL CONTINUE. THINK BEST DAY FOR
SOUTHEAST ARIZONA MAY BE FRIDAY AS CONVERGENCE WILL BE BEST IN THIS
PART OF THE STATE THAT DAY.

THURSDAY SHOULD BE SIMILAR TODAY OUTSIDE OF AREAS THAT SEE MORNING
STORMS. THE EASTERN ZONES SHOULD BE MORE MOIST BY THEN AND HAVE
INCREASED POPS IN THAT AREA ALSO.

STILL DONT SEE AN END TO MONSOON SO WILL KEEP THE CHANCE THROUGH THE
EXTENDED PERIOD. TUS 3345. HOLBROOK

.TWC...NONE.

In the hours before

Special weather statement, Sep 9, 12:45 PM MST, 4 hours 7 minutes before
AZZ019-029>035-100700-
SPECIAL WEATHER STATEMENT...SOUTHEAST ARIZONA CONVECTIVE OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1245 PM MST WED SEP 9 1998...THIS PRODUCT IS NOT UPDATED

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

COCHISE          20           5          10          0    NW 10
GRAHAM           20           5          10          0    NW 10
GREENLEE         40           5          10          0    NW 10
TUCSON/ERN PIMA  40          20          20          5     N 15
TOHONO OODHAM   40          25          30         10     N 20
WESTERN PIMA     40          25          30         10     N 20
SOUTHEAST PINAL  30          20          20         10     N 15
SANTA CRUZ       40          20          20         10     N 15

SYNOPSIS...INCREASING MOISTURE WILL RESULT IN AN INCREASE IN THE
THUNDERSTORM ACTIVITY OVER WESTERN AND CENTRAL PORTIONS OF THE AREA.
THE EAST WILL STILL REMAIN RELATIVELY QUIET TODAY WITH ONLY ISOLATED
THUNDERSTORMS. MID LEVEL WINDS ARE INCREASING AND THUNDERSTORMS WILL
MOVE MORE RAPIDLY NORTH REDUCING THE FLASH FLOOD THREAT ALTHOUGH
STRONG GUSTY WINDS MAY OCCUR WITH STRONGER STORMS.
*****************************************************************
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 12:45 PM 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. CORRESPONDING GRAPHICS MAY BE FOUND ON THE NWS
TUCSON INTERNET PAGE AT
HTTP://NIMBO.WRH.NOAA.GOV/TUCSON/SWO/SWO.SHTML

END/VPH
Special weather statement, Sep 9, 12:45 PM MST, 4 hours 7 minutes before
AZZ019-029>035-100700-
SPECIAL WEATHER STATEMENT...SOUTHEAST ARIZONA CONVECTIVE OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1245 PM MST WED SEP 9 1998...THIS PRODUCT IS NOT UPDATED

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

COCHISE          20           5          10          0    NW 10
GRAHAM           20           5          10          0    NW 10
GREENLEE         40           5          10          0    NW 10
TUCSON/ERN PIMA  40          20          20          5     N 15
TOHONO OODHAM   40          25          30         10     N 20
WESTERN PIMA     40          25          30         10     N 20
SOUTHEAST PINAL  30          20          20         10     N 15
SANTA CRUZ       40          20          20         10     N 15

SYNOPSIS...INCREASING MOISTURE WILL RESULT IN AN INCREASE IN THE
THUNDERSTORM ACTIVITY OVER WESTERN AND CENTRAL PORTIONS OF THE AREA.
THE EAST WILL STILL REMAIN RELATIVELY QUIET TODAY WITH ONLY ISOLATED
THUNDERSTORMS. MID LEVEL WINDS ARE INCREASING AND THUNDERSTORMS WILL
MOVE MORE RAPIDLY NORTH REDUCING THE FLASH FLOOD THREAT ALTHOUGH
STRONG GUSTY WINDS MAY OCCUR WITH STRONGER STORMS.
*****************************************************************
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 12:45 PM 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. CORRESPONDING GRAPHICS MAY BE FOUND ON THE NWS
TUCSON INTERNET PAGE AT
HTTP://NIMBO.WRH.NOAA.GOV/TUCSON/SWO/SWO.SHTML

END/VPH

Nearby

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.