Alert archive / Arizona / Severe Thunderstorm Warnings in 1999
Severe Thunderstorm Warning 4, NWS Tucson, AZ
NWS Tucson, AZ issued this severe thunderstorm warning at Jun 17, 1999, 3:33 PM MST for Pima County, Arizona. It was in force for 42 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
- Jun 17, 1999, 3:33 PM MST (22:33 UTC)
- Expired
- Jun 17, 1999, 4:15 PM MST
- In force
- 42 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 22:33 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, 10.6 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
- 43 J/kg
- Mixed-layer CIN
- -233 J/kg
- Mixed-layer LCL
- 2767 m above ground
- 0-6 km bulk shear
- 12 kt
- 0-1 km storm-relative helicity
- -17 m²/s²
- 0-3 km storm-relative helicity
- 20 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
357 WUUS1 KTUS 172237 RRA SVRTUS AZC019-172315- BULLETIN - EAS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE TUCSON AZ 333 PM MST THU JUN 17 1999 THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... EASTERN PIMA COUNTY IN SOUTHERN ARIZONA * UNTIL 415 PM MST * AT 328 PM MST... DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM IN THE VICINITY OF NORTHWEST TUCSON... MOVING NORTH AT 10 MPH. * THE SEVERE THUNDERSTORM WILL BE NEAR... NORTHWEST TUCSON BY 328 PM MST CONTINENTAL RANCH/MARANA BY 340 PM MST INTERSTATE 10 AT MARANA BY 350 PM MST SEVERE WIND AND BLOWING DUST IS POSSIBLE NEAR INTERSTATE 10 NEAR CORTARO ROAD TO TANGERINE ROAD. LOCALIZED LARGE HAIL IS LIKELY FROM THIS STORM. DRB
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 Jun 17, 2:13 PM MST, 1 hour 20 minutes earlier.
Area forecast discussion, Jun 17, 2:13 PM MST, 1 hour 20 minutes before
SOUTHEAST ARIZONA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TUCSON AZ 213 PM MST THU JUN 17 1999 SYNOPSIS...HIGH PRESSURE OVER NEW MEXICO WILL REMAIN NEARLY STATIONARY THROUGH SUNDAY. THE HIGH WILL CONTINUE TO PUMP MOIST AIR INTO ARIZONA FROM THE SOUTH AND SOUTHEAST...RESULTING IN A DAILY THREAT OF AFTERNOON AND EVENING THUNDERSTORMS. A DRIER AIR FLOW IS NOT EXPECTED TO DEVELOP UNTIL AT LEAST TUESDAY. DISCUSSION...RADAR ALREADY BUSY THIS AFTERNOON WITH A COUPLE OF CELLS ALREADY NEAR SEVERE LIMITS. HAVE EVEN HAD MARBLE-SIZED HAIL ON MT. LEMMON. STORMS GOT GOING EARLIER TODAY JUST EAST OF THE SANTA CRUZ RIVER WHERE SATELLITE INDICATES SOME MID LEVEL CONVERGENCE. WEAK SE-SW SHEAR IS ALSO FAVORABLE FOR SUSTAINING STRONG UPDRAFTS. THUS WE'LL RETAIN THE HEIGHTENED WORDING AGAIN THIS EVENING. RAPID-SCAN SATELLITE UPDATES WILL HELP OUT AS WE TRY TO KEEP TABS ON ANY CELLS ENTERING BEAM-BLOCKED AREAS. NEXT 2 DAYS COULD BE ALMOST AS BUSY. ORIGINALLY THOUGHT THAT THE POCKET OF DRY AIR MOVING UP THE NORTHERN GULF OF CALIFORNIA WOULD MODIFY THIS SOUP THAT ADVECTED IN FROM THE EAST. NO SUCH LUCK. RECENT GOES PRECIP WATER IMAGERY SHOWS A BLOB OF 1.5" PRECIP WATER GATHERING OVER THE SOUTHERN GULF AND GETTING ENTRAINED NORTH. I ALSO SEE NO REASON FOR THIS WEAK, LOW LEVEL, SE FLOW TO SHUT DOWN. AFTER GETTING WORKED OVER TODAY AND WITH SLIGHTLY WEAKER MID LEVEL SHEAR TOMORROW, I THINK WE'LL RAMP DOWN JUST A LITTLE BEFORE THE SHEAR INCREASES AGAIN SATURDAY. WE MAY ALSO GET A LITTLE HELP FROM DYNAMICS SATURDAY WHEN THE WEAK UPPER LOW OFF THE CENTRAL BAJA JOGS NORTH TO THE N BAJA. BASIC GIST OF THE FORECAST IS TO HAVE SCATTERED AFTERNOON/EVENING ACTIVITY RIGHT INTO THE EXTENDED. IF MEDIUM RANGE MODELS WERE IN BETTER AGREEMENT OF WHEN DRIER SW FLOW WILL KICK IN, I'D TRY TO SWITCH TO SCATTERED WORDING IN THE EXTENDED INSTEAD OF USING THE "CHANCE" BROADBRUSH. NO SENSE FINESSING, THOUGH, WITH BASIC PAbTTERN SHOWING NO SIGNS OF CHANGING UNTIL DAY 5 OR SO. TO GIVE YOU AN IDEA ON HOW RARE THIS IS, THE CLIMO CHANCE OF PRECIP FOR JUNE 17 IN TUCSON IS A WHOPPING 4% (IT'S RAINED ONLY 4 TIMES IN 129 YEARS OF RECORDS). PYTLAK .TWC...NONE.
In the hours before
Special weather statement, Jun 17, 12:22 PM MST, 3 hours 11 minutes before
AZZ019-030>035-172300-
SPECIAL WEATHER STATEMENT...SOUTHEAST ARIZONA CONVECTIVE OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1222 PM MST THU JUN 17 1999...THIS PRODUCT IS NOT UPDATED
*CONDITIONAL* *CONDITIONAL*
COUNTY AREAL PROBABILITY RAIN GREATER THAN STORM
COVERAGE OF SEVERE 1.00 2.00 MOTION
COCHISE 30 50 0 0 N 12 MPH
GRAHAM 30 50 0 0 N 12 MPH
GREENLEE 50 10 0 0 N 12 MPH
TUCSON/ERN PIMA 30 40 0 0 NNE 12 MPH
TOHONO OODHAM 5 0 0 0 NNE 12 MPH
SOUTHEAST PINAL 30 40 0 0 N 12 MPH
WESTERN PIMA 0 0 0 0
SANTA CRUZ 40 30 0 0 NNE 12 MPH
SYNOPSIS...MORE MOISTURE HAS FED INTO THE AREA FROM THE SOUTHERN
PLAINS AND GULF OF MEXICO. THIS HAS DESTABILIZED THE ATMOSPHERE MORE
THAN YESTERDAY. IN ADDITION...THERE ARE SOUTHEAST WINDS AT THE
SURFACE AND SOUTHWEST WINDS ALOFT. THIS WEAK WIND SHEAR ALOFT WILL
HELP TO SUSTAIN RATHER STRONG THUNDERSTORMS WHICH WILL BE CAPABLE OF
PRODUCING MICROBURST WIND GUSTS OVER 40 MPH AND DENSE CLOUDS OF
BLOWING DUST. RAINFALL WILL BE GENERALLY LIGHT SINCE THE LOWEST
LEVELS OF THE ATMOSPHERE REMAIN ON THE DRY SIDE.
*******************************************************
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 1245 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. ACCOMPANYING GRAPHICS FOR THIS PRODUCT WILL NOT
BE AVAILABLE UNTIL JULY 1 1999.
END/PYTLAKSpecial weather statement, Jun 17, 12:22 PM MST, 3 hours 11 minutes before
AZZ019-030>035-172300-
SPECIAL WEATHER STATEMENT...SOUTHEAST ARIZONA CONVECTIVE OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1222 PM MST THU JUN 17 1999...THIS PRODUCT IS NOT UPDATED
*CONDITIONAL* *CONDITIONAL*
COUNTY AREAL PROBABILITY RAIN GREATER THAN STORM
COVERAGE OF SEVERE 1.00 2.00 MOTION
COCHISE 30 50 0 0 N 12 MPH
GRAHAM 30 50 0 0 N 12 MPH
GREENLEE 50 10 0 0 N 12 MPH
TUCSON/ERN PIMA 30 40 0 0 NNE 12 MPH
TOHONO OODHAM 5 0 0 0 NNE 12 MPH
SOUTHEAST PINAL 30 40 0 0 N 12 MPH
WESTERN PIMA 0 0 0 0
SANTA CRUZ 40 30 0 0 NNE 12 MPH
SYNOPSIS...MORE MOISTURE HAS FED INTO THE AREA FROM THE SOUTHERN
PLAINS AND GULF OF MEXICO. THIS HAS DESTABILIZED THE ATMOSPHERE MORE
THAN YESTERDAY. IN ADDITION...THERE ARE SOUTHEAST WINDS AT THE
SURFACE AND SOUTHWEST WINDS ALOFT. THIS WEAK WIND SHEAR ALOFT WILL
HELP TO SUSTAIN RATHER STRONG THUNDERSTORMS WHICH WILL BE CAPABLE OF
PRODUCING MICROBURST WIND GUSTS OVER 40 MPH AND DENSE CLOUDS OF
BLOWING DUST. RAINFALL WILL BE GENERALLY LIGHT SINCE THE LOWEST
LEVELS OF THE ATMOSPHERE REMAIN ON THE DRY SIDE.
*******************************************************
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 1245 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. ACCOMPANYING GRAPHICS FOR THIS PRODUCT WILL NOT
BE AVAILABLE UNTIL JULY 1 1999.
END/PYTLAKThe office that day
Everything else NWS Tucson, AZ issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 17, 2:46 PM MST | Severe Thunderstorm Warning | TWC | Cochise | 34 min |
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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.