Alert archive / Arizona / Severe Thunderstorm Warnings in 1998
Severe Thunderstorm Warning 84, NWS Tucson, AZ
NWS Tucson, AZ issued this severe thunderstorm warning at Sep 6, 1998, 4:10 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
- Sep 6, 1998, 4:10 PM MST (23:10 UTC)
- Expired
- Sep 6, 1998, 5:00 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 23:12 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, 11.2 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
- 21 J/kg
- Mixed-layer CIN
- -359 J/kg
- Mixed-layer LCL
- 2503 m above ground
- 0-6 km bulk shear
- 14 kt
- 0-1 km storm-relative helicity
- 16 m²/s²
- 0-3 km storm-relative helicity
- 97 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
121 WUUS1 KTUS 062311 RRA SVRTUS AZC019-062355- BULLETIN - EAS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE TUCSON AZ 410 PM MST SUN SEP 6 1998 THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... SOUTHEASTERN PIMA COUNTY IN SOUTHERN ARIZONA INCLUDING ARIVACA JUNCTION AND GREEN VALLEY * UNTIL 500 PM MST * AT 408 PM MST... DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 10 MILES SOUTH OF GREEN VALLEY OR 2 MILES NORTHWEST OF ARIVACA JUNCTION MOVING NORTH AT 10 MPH. WINDS TO 60 MPH ARE POSSIBLE WITH THIS STORM ALONG WITH FREQUENT LIGHTNING AND HEAVY RAIN. WJM
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 6, 2:30 PM MST, 1 hour 40 minutes earlier.
Area forecast discussion, Sep 6, 2:30 PM MST, 1 hour 40 minutes before
SOUTHEAST ARIZONA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TUCSON AZ 230 PM MST SUN SEP 6 1998 SYNOPSIS...DRIER AIR WORKING ITS WAY INTO SOUTHEAST ARIZONA FROM THE EAST WILL BRING A DECREASE IN THUNDERSTORM ACTIVITY FOR THE NEXT COUPLE OF DAYS. DISCUSSION...THUNDERSTORMS FIRING OFF THIS AFTERNOON ALONG RESIDUAL MOISTURE BOUNDRY FROM ABOUT TUCSON WESTWARD. DRIER AIR HAS WORKED ITS WAY INTO THE EASTERN AREAS...IE GRAHAM AND COCHISE COUNTIES EASTWARD...WHERE ONLY A FEW FLAT CUMULUS HAVE DEVELOPED SO FAR. EVEN FARTHER EAST IN NEW MEXICO SKIES ARE CLOUD FREE. SO NOT EXPECTING MUCH IN THE EAST THIS EVENING. THIS DRIER AIR WILL ADVECT INTO ALL OF SOUTHEAST ARIZONA ON LABOR DAY RESULTING IN LITTLE IF ANY THUNDERSTORM ACTIVITY. GUT FEELING IS THAT THE EASTERN HALF WILL SEE NO THUNDERSTORM ACTIVITY WITH A SLIGHT CHANCE AT BEST OUT WEST WHERE ENOUGH RESIDUAL MOISTURE COULD STILL EXIST FOR A THUNDERSTORM. BUT WILL KEEP MINIMAL 10 PERCENT POPS IN ALL AREAS BUT MAINLY OVER THE MOUNTAINS AS ITS HARD TO RULE THUNDERSTORMS OUT COMPLETELY THIS TIME OF YEAR. NOT MUCH CHANGE ON TUESDAY AS DRIER AIR CONTINUES OVER SOUTHEAST ARIZONA ACCORDING TO THE MODELS. IN THE 3-5 DAY PERIOD WILL GO WITH STANDARD MONSOON FORECAST OF A CHANCE OF AFTERNOON AND EVENING THUNDERSTORMS AS MRF MODEL TRIES TO BRING TROPICAL STORM UP ALONG THE WEST COAST OF BAJA AND WITH UPPER TROUGH PASSING THROUGH THE GREAT BASIN ON WEDNESDAY IT COULD SUCK SOME OF THIS MOISTURE INTO SOUTHEAST ARIZONA THEN FOUR-CORNERS HIGH REESTABLISHES ITSELF ON THURSDAY AND FRIDAY. TUS 2111. COLLINS .TWC...NONE.
In the hours before
Special weather statement, Sep 6, 12:45 PM MST, 3 hours 25 minutes before
AZZ019-029>035-070700-
SPECIAL WEATHER STATEMENT...SOUTHEAST ARIZONA CONVECTIVE OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1245 PM MST SUN SEP 6 1998...THIS PRODUCT IS NOT UPDATED
*CONDITIONAL* *CONDITIONAL*
AREAL PROBABILITY RAIN GREATER THAN STORM
COUNTY COVERAGE OF SEVERE 1.00 2.00 MOTION
COCHISE 10 10 10 0 NW 15
GRAHAM 10 10 10 0 NW 15
GREENLEE 15 10 10 0 NW 15
TUCSON/ERN PIMA 20 15 20 5 N 15
TOHONO OODHAM 25 20 30 10 N 15
WESTERN PIMA 25 20 30 10 NE 15
SOUTHEAST PINAL 25 20 30 10 N 15
SANTA CRUZ 20 15 20 5 N 15
SYNOPSIS...DRIER AIR MOVING IN FROM THE EAST WILL BRING A DOWNTURN
IN ACTIVITY FROM TUCSON EASTWARD. GREATER MOISTURE AND LIFT WEST OF
TUCSON WILL BRING BETTER CHANCES OF THUNDERSTORMS THAT AREA.
*****************************************************************
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/CECSpecial weather statement, Sep 6, 12:45 PM MST, 3 hours 25 minutes before
AZZ019-029>035-070700-
SPECIAL WEATHER STATEMENT...SOUTHEAST ARIZONA CONVECTIVE OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1245 PM MST SUN SEP 6 1998...THIS PRODUCT IS NOT UPDATED
*CONDITIONAL* *CONDITIONAL*
AREAL PROBABILITY RAIN GREATER THAN STORM
COUNTY COVERAGE OF SEVERE 1.00 2.00 MOTION
COCHISE 10 10 10 0 NW 15
GRAHAM 10 10 10 0 NW 15
GREENLEE 15 10 10 0 NW 15
TUCSON/ERN PIMA 20 15 20 5 N 15
TOHONO OODHAM 25 20 30 10 N 15
WESTERN PIMA 25 20 30 10 NE 15
SOUTHEAST PINAL 25 20 30 10 N 15
SANTA CRUZ 20 15 20 5 N 15
SYNOPSIS...DRIER AIR MOVING IN FROM THE EAST WILL BRING A DOWNTURN
IN ACTIVITY FROM TUCSON EASTWARD. GREATER MOISTURE AND LIFT WEST OF
TUCSON WILL BRING BETTER CHANCES OF THUNDERSTORMS THAT AREA.
*****************************************************************
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/CECNearby
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.