Alert archive / Arizona / Severe Thunderstorm Warnings in 1999
Severe Thunderstorm Warning 43, NWS Tucson, AZ
NWS Tucson, AZ issued this severe thunderstorm warning at Jul 24, 1999, 3:45 PM MST for Pima County, Arizona. It was in force for 45 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
- Jul 24, 1999, 3:45 PM MST (22:45 UTC)
- Expired
- Jul 24, 1999, 4:30 PM MST
- In force
- 45 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 22:48 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 24, 3:58 PM MST | Thunderstorm Wind 82 | Davis Monthan Afb, AZ |
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 nearest sounding before it
Tuscon, AZ (KTUS), launched 12:00Z, 10.8 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
- 380 J/kg
- Mixed-layer CIN
- -127 J/kg
- Mixed-layer LCL
- 1266 m above ground
- 0-6 km bulk shear
- 3 kt
- 0-1 km storm-relative helicity
- -9 m²/s²
- 0-3 km storm-relative helicity
- -21 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.
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 Jul 24, 2:05 PM MST, 1 hour 40 minutes earlier.
Area forecast discussion, Jul 24, 2:05 PM MST, 1 hour 40 minutes before
SOUTHEAST ARIZONA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TUCSON AZ 205 PM MST SAT JUL 24 1999 SYNOPSIS...HIGH PRESSURE ALOFT WILL SHIFT FROM THE CENTRAL PLAINS INTO THE FOUR CORNERS AREA BY MONDAY. SCATTERED AFTERNOON AND EVENING THUNDERSTORMS WILL CONTINUE...BUT THEY WILL BECOME MORE NUMEROUS AND ORGANIZED BY MONDAY AS A DISTURBANCE MOVES WEST FROM THE GULF OF MEXICO. DISCUSSION...COVERAGE HAS BEEN SOMEWHAT SUPPRESSED THIS AFTERNOON, AT LEAST SO FAR. ENOUGH MID LEVEL DRYING HAS SPREAD INTO COCHISE COUNTY TO KEEP THE COVERAGE THERE VERY ISOLATED. THAT DRY POCKET, THOUGH, IS CLOSING UP AS LEADING EDGE OF DEEP GULF OF MEXICO PUSHES INTO THE SIERRA MADRES. COMBINED WITH WEAK DIVERGENCE ALOFT AND 20KT SSE FLOW, WE SHOULD GET AN MCS OR MCC THIS EVENING TO OUR SE WITH ITS REMNANTS PUSHING INTO AREAS THAT MAY MISS THE FIRST ROUND THIS EVENING. IN ESSENCE, IM GOING TO STICK WITH OUR GOING FORECAST: SCATTERED STUFF THIS EVENING DIMINISHING TO ISOLATED ANVIL SHOWERS OVERNIGHT, FOLLOWED BY MOUNTAIN HUGGING AFTERNOON CELLS TRANSITIONING TO SCATTERED VALLEY STORMS ON SUNDAY. MONDAY LOOKS LIKE A BIG DAY AS 4-CORNER HIGH GETS INTO POSITION AND DEEP SE-S FLOW RUNS INTO THE 20KT RANGE. THERES A CHANCE OF AN ACTIVE DAY TOMORROW SINCE DEEP SE FLOW AND GULF OF MEXICO MOISTURE WILL ALREADY BE IN PLACE, BUT IT LOOKS LIKE WELL BE MISSING A FOCUSING MECHANISM UNTIL THE MCS-INDUCED WAVE OFF THE TX COAST MOVES WEST TOWARD OUR NEIGHBORHOOD. MODELS DO A TERRIBLE JOB WITH IT, SO ILL HAVE TO RELY ON EXTRAPOLATION. BEST GUESS IS ARRIVAL LATE SUNDAY NIGHT OR MONDAY, WHICH AGREES WELL WITH UPPER LEVEL RIDGE DEVELOPMENT. GULF SURGE POTENTIAL WILL BE HIGH OVER THE NEXT SEVERAL DAYS, BUT WITH DEWPOINTS ALREADY WELL INTO THE 60S, WILL IT REALLY MATTER? LONGWAVE LOOKS VERY ACTIVE FOR THE UPCOMING WEEK WITH STRIKING SIMILARITIES TO THE 1ST WEEK OF JULY WHEN WE HAD A DAILY SEVERE WEATHER/FLASH FLOOD THREAT. THIS IS DEFINITELY NOT A QUIET MONSOON SEASON THIS YEAR PYTLAK .TWC...NONE.
In the hours before
Special weather statement, Jul 24, 11:30 AM MST, 4 hours 15 minutes before
AZZ019-029>035-250500-
SPECIAL WEATHER STATEMENT...SOUTHEAST ARIZONA CONVECTIVE OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1130 AM MST SAT JUL 24 1999...THIS PRODUCT IS NOT UPDATED
*CONDITIONAL* *CONDITIONAL*
COUNTY AREAL PROBABILITY RAIN GREATER THAN STORM
COVERAGE OF SEVERE 1.00 2.00 MOTION
COCHISE 50 20 35 20 NW10
GRAHAM 50 20 35 10 NW10
GREENLEE 60 15 40 10 NW12
TUCSON/ERN PIMA 45 25 40 20 NW10
TOHONO OODHAM 40 30 50 25 NW8
SOUTHEAST PINAL 40 20 40 20 NW10
WESTERN PIMA 35 30 50 25 NW6
SANTA CRUZ 55 20 35 20 NW10
SYNOPSIS...THE ATMOSHPERE REMAINS MOST AND UNSTABLE ACROSS THE
AREA...BUT THERE ARE NO DISTURBANCES TO FOCUS THUNDERSTORM
DEVELOPMENT THIS AFTERNOON OR EVENING. THE DEEPEST MOISTURE WILL
RESIDE WEST OF TUCSON THIS EVENING...WHICH IS WHERE THE THREAT OF
HEAVYU DOWNPOURS WILL BE HIGHEST. STEERING WINDS ARE STRONGER
TODAY WHICH WILL KEEP THE STORMS FROM GETTING STUCK IN ONE PLACE.
HOWEVER THOSE SAME WINDS SHOULD ALLOW STORMS THAT INITIALLY FORM
ON THE MOUNTAINS TO SPREAD INTO THE VALLEYS AND DESERTS BY LATE
AFTERNOON...SOME OF WHICH COULD GET RATHER STRONG. A THUNDERSTORM
COMPLEX MAY FORM SOUTH OF DOUGLAS THIS EVENING WITH ITS REMNANTS
SPILLING NORTH INTO THE AREA LATE TONIGHT.
*****************************************************************
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/PYTLAKSpecial weather statement, Jul 24, 11:30 AM MST, 4 hours 15 minutes before
AZZ019-029>035-250500-
SPECIAL WEATHER STATEMENT...SOUTHEAST ARIZONA CONVECTIVE OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1130 AM MST SAT JUL 24 1999...THIS PRODUCT IS NOT UPDATED
*CONDITIONAL* *CONDITIONAL*
COUNTY AREAL PROBABILITY RAIN GREATER THAN STORM
COVERAGE OF SEVERE 1.00 2.00 MOTION
COCHISE 50 20 35 20 NW10
GRAHAM 50 20 35 10 NW10
GREENLEE 60 15 40 10 NW12
TUCSON/ERN PIMA 45 25 40 20 NW10
TOHONO OODHAM 40 30 50 25 NW8
SOUTHEAST PINAL 40 20 40 20 NW10
WESTERN PIMA 35 30 50 25 NW6
SANTA CRUZ 55 20 35 20 NW10
SYNOPSIS...THE ATMOSHPERE REMAINS MOST AND UNSTABLE ACROSS THE
AREA...BUT THERE ARE NO DISTURBANCES TO FOCUS THUNDERSTORM
DEVELOPMENT THIS AFTERNOON OR EVENING. THE DEEPEST MOISTURE WILL
RESIDE WEST OF TUCSON THIS EVENING...WHICH IS WHERE THE THREAT OF
HEAVYU DOWNPOURS WILL BE HIGHEST. STEERING WINDS ARE STRONGER
TODAY WHICH WILL KEEP THE STORMS FROM GETTING STUCK IN ONE PLACE.
HOWEVER THOSE SAME WINDS SHOULD ALLOW STORMS THAT INITIALLY FORM
ON THE MOUNTAINS TO SPREAD INTO THE VALLEYS AND DESERTS BY LATE
AFTERNOON...SOME OF WHICH COULD GET RATHER STRONG. A THUNDERSTORM
COMPLEX MAY FORM SOUTH OF DOUGLAS THIS EVENING WITH ITS REMNANTS
SPILLING NORTH INTO THE AREA LATE TONIGHT.
*****************************************************************
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/PYTLAKThe office that day
Everything else NWS Tucson, AZ issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 23, 6:34 PM MST | Flash Flood Warning | TWC | Cochise | 86 min |
| Jul 24, 4:09 PM MST | Flash Flood Warning | TWC | Pima | 81 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.