Alert archive / Arizona / Severe Thunderstorm Warnings in 1999
Severe Thunderstorm Warning 101, NWS Tucson, AZ
NWS Tucson, AZ issued this severe thunderstorm warning at Sep 15, 1999, 5:03 PM MST for Pinal County, Arizona. It was in force for 42 min. 1 report came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- Sep 15, 1999, 5:03 PM MST (00:03 UTC)
- Expired
- Sep 15, 1999, 5:45 PM MST
- In force
- 42 min
- Issued by
- NWS Tucson, AZ
- Area
- Whole counties
County Pinal County, AZ
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Sep 15, 5:30 PM MST | Hail 0.75 | Superior, AZ | Large hail was reported throughout the area along with heavy rain. One spotter about 7 miles east of Superior, at Top of the World, reported 1.10 inch in just 25 minutes. |
NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.
The watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Sep 15, 12:30 PM MST | Severe Thunderstorm Watch | SPC | 6 hr |
The nearest sounding before it
Tuscon, AZ (KTUS), launched 00:00Z, 0.1 hours before the alert went out and 92 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
- 180 J/kg
- Mixed-layer CIN
- -272 J/kg
- Mixed-layer LCL
- 2091 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- -41 m²/s²
- 0-3 km storm-relative helicity
- -46 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.2
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KTUS 160005 RRA SVRTUS AZC021-160050- BULLETIN - EAS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE TUCSON AZ 503 PM MST WED SEP 15 1999 THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... NORTH CENTRAL PINAL COUNTY IN SOUTH CENTRAL ARIZONA * UNTIL 545 PM MST * AT 459 PM MST... DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 10 MILES NORTHEAST OF FLORENCE MOVING NORTHEAST 15 MPH. * THE SEVERE TzHUNDERSTORM WILL BE NEAR... KELVIN BY 515 PM HIGHWAY 177 525 PM THIS THUNDERSTORM WILL PRODUCE DAMAGING WINDS AND LARGE HAIL. TAKE COVER AS THE SEVERE THUNDERSTORM APPROACHES.
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 15, 2:10 PM MST, 2 hours 53 minutes earlier.
Area forecast discussion, Sep 15, 2:10 PM MST, 2 hours 53 minutes before
SOUTHEAST ARIZONA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TUCSON AZ 210 PM MST WED SEP 15 1999 SYNOPSIS...SUFFICIENT MOISTURE...HEATING AND INSTABILITY WILL CONTINUE THE THREAT FOR MAINLY AFTERNOON AND EVENING THUNDERSTORMS THROUGH THURSDAY. SOME OF THESE STORMS ARE EXPECTED TO BE QUITE STRONG. DRIER AIR BEGINNING TO MOVE INTO WESTERN PIMA COUNTY WILL SLOWLY WORK ITS WAY EAST THROUGH THE REST OF THE WEEK. EVEN SO...THERE WILL STILL LIKELY BE ENOUGH MOISTURE AROUND THIS WEEKEND FOR A CHANCE OF THUNDERSTORMS OVER THE EASTERN MOUNTAINS. DISCUSSION...STRONG SHEAR PROFILE THIS AFTERNOON FOR WIDESPREAD SEVERE CONVECTION. FOCUS HAS SHIFTED SOUTH AND EAST TO INCLUDE MOST OF THE CWA INCLUDING METRO TUCSON. MAIN ENERGY FROM TROUGH PULLING OUT OF THE GREAT BASIN THE NEXT 24 HRS...BUT A PIECE TRAILS A BIT IN EASTERN ARIZONA AS WELL AS A WEAK IMPULSE CAUGHT IN THE WESTERLIES DOWN AROUND THIS LATITUDE TO HELP FOCUS THINGS. A RELATIVELY WEAK SUBSIDENCE INVERSION SMASHED TO SMITHEREENS WITH BARELY A BACKWARD GLANCE. BRISK WESTERLY FLOW...BUT IMMEDIATE UPSTREAM OF THAT FOR OUR AREA STILL CONTAINS 1 INCH PRECIPITABLE WATER VALUES. WELL START TO SEE SOME DRYING IN THE FAR WEST...BUT NOT MUCH OF THAT INFLUENCING THINGS AROUND HERE THE NEXT COUPLE OF DAYS WITH WEAK SOUTHERLY COMPONENT TO FLOW RETURNING IN EASTERN PORTIONS AS SHORTWAVE RIDGING PUSHES UP OUT OF OLD MEXICO. MEYER .TWC...NONE.
In the hours before
Special weather statement, Sep 15, 12:05 PM MST, 4 hours 58 minutes before
AZZ019-029-030-032-033-035-160100- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE TUCSON AZ 1205 PM MST WED SEP 15 1999 ...SEVERE THUNDERSTORM WATCH UNTIL 6 PM MST FOR PORTIONS OF SOUTHEAST ARIZONA... A SEVERE THUNDERSTORM WATCH IS IN EFFECT UNTIL 6 PM FOR SOUTHEAST PINAL...GRAHAM...GREENLEE...CENTRAL PIMA...EASTERN PIMA AND NORTHERN COCHISE COUNTIES. THIS INCLUDES LOCATIONS SUCH AS METROPOLITAN TUCSON...SELLS...GREEN VALLEY...ORACLE...SAFFORD...CLIFTON... BENSON...AND WILLCOX. A SEVERE THUNDERSTORM WATCH MEANS THAT CONDITIONS ARE FAVORABLE FOR THE DEVELOPMENT OF SEVERE THUNDERSTORMS. THIS INCLUDES DAMAGING WINDS IN EXCESS OF 60 MPH AND LARGE HAIL. IN ADDITION AREA OF BLOWING DUST ARE POSSIBLE AWAY FROM STORMS AND LOCALLY HEAVY RAINFALL WILL BE EXPERIENCED WITH STORMS. MEYER
Special weather statement, Sep 15, 12:05 PM MST, 4 hours 58 minutes before
AZZ019-029-030-032-033-035-160100- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE TUCSON AZ 1205 PM MST WED SEP 15 1999 ...SEVERE THUNDERSTORM WATCH UNTIL 6 PM MST FOR PORTIONS OF SOUTHEAST ARIZONA... A SEVERE THUNDERSTORM WATCH IS IN EFFECT UNTIL 6 PM FOR SOUTHEAST PINAL...GRAHAM...GREENLEE...CENTRAL PIMA...EASTERN PIMA AND NORTHERN COCHISE COUNTIES. THIS INCLUDES LOCATIONS SUCH AS METROPOLITAN TUCSON...SELLS...GREEN VALLEY...ORACLE...SAFFORD...CLIFTON... BENSON...AND WILLCOX. A SEVERE THUNDERSTORM WATCH MEANS THAT CONDITIONS ARE FAVORABLE FOR THE DEVELOPMENT OF SEVERE THUNDERSTORMS. THIS INCLUDES DAMAGING WINDS IN EXCESS OF 60 MPH AND LARGE HAIL. IN ADDITION AREA OF BLOWING DUST ARE POSSIBLE AWAY FROM STORMS AND LOCALLY HEAVY RAINFALL WILL BE EXPERIENCED WITH STORMS. MEYER
Special weather statement, Sep 15, 12:45 PM MST, 4 hours 18 minutes before
AZZ019-029>035-160500-
SPECIAL WEATHER STATEMENT...SOUTHEAST ARIZONA CONVECTIVE OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1245 PM MST WED SEP 15 1999...THIS PRODUCT IS NOT UPDATED
...SEVERE THUNDERSTORM WATCH UNTIL 6 PM MST FOR SOUTHEAST PINAL...
CENTRAL PIMA...EASTERN PIMA...GRAHAM...GREENLEE...AND NORTHERN
COCHISE COUNTIES...
*CONDITIONAL* *CONDITIONAL*
COUNTY AREAL PROBABILITY RAIN GREATER THAN STORM
COVERAGE OF SEVERE 1.00 2.00 MOTION
COCHISE 40 20 35 5 E 15
GRAHAM 50 30 45 5 E 20
GREENLEE 65 30 45 5 E 20
TUCSON/ERN PIMA 40 25 45 5 E 15
TOHONO OODHAM 35 20 45 5 E 12
SOUTHEAST PINAL 40 25 45 5 E 15
WESTERN PIMA 20 5 45 5 ESE10
SANTA CRUZ 40 10 45 5 ESE10
SYNOPSIS...MOIST AND VERY UNSTABLE THIS AFTERNOON. WIND SHEAR
PROFILE INDICATES STRONG SEVERE WEATHER SIGNATURES. FAST MOVING
SO FLOODING IS NOT A BIG CONCERN. EASTERN AREAS COULD SEE
ACTIVITY SUSTAINED WELL INTO THE EVENING.
*****************************************************************
KEY...
AREAL COVERAGE - PERCENT OF COUNTY OR AREA THAT WILL EXPERIENCE
THUNDERSTORMS
PROB OF SEVERE - THE PROBABILITY THAT AN INDIVIDUAL STORM WILL
REACH SEVERE LEVELS (DAMAGING WIND AND/OR
LARGE HAIL)
RAIN GRTR THAN - THE PROBABILITY THAT AN INDIVIDUAL STORM 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/Special weather statement, Sep 15, 12:45 PM MST, 4 hours 18 minutes before
AZZ019-029>035-160500-
SPECIAL WEATHER STATEMENT...SOUTHEAST ARIZONA CONVECTIVE OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1245 PM MST WED SEP 15 1999...THIS PRODUCT IS NOT UPDATED
...SEVERE THUNDERSTORM WATCH UNTIL 6 PM MST FOR SOUTHEAST PINAL...
CENTRAL PIMA...EASTERN PIMA...GRAHAM...GREENLEE...AND NORTHERN
COCHISE COUNTIES...
*CONDITIONAL* *CONDITIONAL*
COUNTY AREAL PROBABILITY RAIN GREATER THAN STORM
COVERAGE OF SEVERE 1.00 2.00 MOTION
COCHISE 40 20 35 5 E 15
GRAHAM 50 30 45 5 E 20
GREENLEE 65 30 45 5 E 20
TUCSON/ERN PIMA 40 25 45 5 E 15
TOHONO OODHAM 35 20 45 5 E 12
SOUTHEAST PINAL 40 25 45 5 E 15
WESTERN PIMA 20 5 45 5 ESE10
SANTA CRUZ 40 10 45 5 ESE10
SYNOPSIS...MOIST AND VERY UNSTABLE THIS AFTERNOON. WIND SHEAR
PROFILE INDICATES STRONG SEVERE WEATHER SIGNATURES. FAST MOVING
SO FLOODING IS NOT A BIG CONCERN. EASTERN AREAS COULD SEE
ACTIVITY SUSTAINED WELL INTO THE EVENING.
*****************************************************************
KEY...
AREAL COVERAGE - PERCENT OF COUNTY OR AREA THAT WILL EXPERIENCE
THUNDERSTORMS
PROB OF SEVERE - THE PROBABILITY THAT AN INDIVIDUAL STORM WILL
REACH SEVERE LEVELS (DAMAGING WIND AND/OR
LARGE HAIL)
RAIN GRTR THAN - THE PROBABILITY THAT AN INDIVIDUAL STORM 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/Nearby
Severe Thunderstorm Warnings in Arizona, 1999Every severe thunderstorm warning in 1999
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.