Alert archive / Arizona / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 20, NWS Tucson, AZ

July 12, 2002Pima County, Arizona

NWS Tucson, AZ issued this severe thunderstorm warning at Jul 12, 2002, 7:13 PM MST for Pima County, Arizona. It was in force for 32 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jul 12, 2002, 7:13 PM MST (02:13 UTC)
Expired: Jul 12, 2002, 7:45 PM MST
In force: 32 min
Issued by: NWS Tucson, AZ
Area: Counties, with a storm outline in the text

County Pima County, AZ

The radar

The Tucson radar (KEMX), 38 km from the middle of the area, began a volume at 02:16 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Tuscon, AZ (KTUS), launched 00:00Z, 2.2 hours before the alert went out and 14 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 820 J/kg
Mixed-layer CIN: -16 J/kg
Mixed-layer LCL: 3273 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 20 m²/s²
0-3 km storm-relative helicity: 97 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

810 
WUUS55 KTWC 130213
SVRTWC
AZC019-130245-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TUCSON AZ
712 PM MST FRI JUL 12 2002

THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EAST CENTRAL PIMA COUNTY IN ARIZONA

* UNTIL 745 PM MST

* AT 701 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM ON THE EAST SIDE OF TUCSON MOVING SOUTHWEST 
  AROUND 10 MPH.

GO INSIDE A STRONG BUILDING. DAMAGING DOWNBURSTS WINDS...DEADLY 
LIGHTNING...AND BRIEF HEAVY RAINS AND SMALL HAIL ARE LIKELY.

ADDITIONAL THUNDESTORM DEVELOPMENT ACROSS THE TUCSON METRO AREA WILL 
CONTINUE THROUGH 8 PM...SOME OF WHICH MAY BECOME SEVERE.

LAT...LON 3231 11069 3232 11088 3207 11088 3209 11068

GLUECK

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 12, 2:30 PM MST, 4 hours 43 minutes earlier.

Area forecast discussion, Jul 12, 2:30 PM MST, 4 hours 43 minutes before

SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
230 PM MST FRI JUL 12 2002

.SYNOPSIS...HIGH PRESSURE OVER UTAH WILL KEEP DEEP EASTERLY FLOW
OVER THE REGION INTO THE WEEKEND. THIS WILL GUIDE A SERIES OF
DISTURBANCES OFF THE GULF OF MEXICO AND SOUTHERN PLAINS...LEADING TO
A DAILY RISK OF THUNDERSTORMS THROUGH EARLY NEXT WEEK.

.DISCUSSION...LITTLE BIT OF A DRY PUNCH PUSHING IN FROM THE THE
NORTHEAST EVIDENT ON WATER VAPOR IMAGERY AND GOES SOUNDER PW
ESTIMATES...BUT NOT ENOUGH TO INHIBIT CONVECTION OVER THE EAST
CENTRAL MOUNTAINS. OTHERWISE...PRECIPITABLE WATER VALUES IN THE 12Z
KTUS SOUNDING SIMILAR TO RECENT DAYS...IN THE 1.2 TO 1.3 INCH RANGE.
SURFACE DEWPTS HAVE AGAIN MIXED OUT TO THE LOWER 50S ACROSS THE AREA
THIS AFTERNOON. MAKES FOR A LOW SCATTERED MOUNTAIN / ISOLATED VALLEY
THUNDERSTORM DAY WITH ONE OR TWO POTENTIALLY SEVERE. WELL NEED TO
WATCH AS OUTFLOW COMES OFF THE RIM AS WELL.

NICE LITTLE COMPLEX OVER CENTRAL TO SOUTHERN SONORA FORMED OVERNIGHT
AND PUSHED OFF INTO THE GULF OF CALIFORNIA. SLIGHT TO MODERATE
PRESSURE DIFFERENTIAL DOWN THE GULF AS WELL (SEEMS TO BE FILLING IN
FAIRLY RAPIDLY TODAY THOUGH). LOOKING MORE AND MORE LIKE WELL SEE
A SURGE ENHANCEMENT THROUGH THE LOWER DESERTS OVER THE NEXT 36HRS AS
HINTED AT BY THE MESO-ETA. THIS WOULD BE ON TOP OF THE 10 TO 15KTS
UP TO 4K FT ALREADY EVIDENT ON THE YUMA VWP. WELL FOCUS ON SUNDAY
AND/OR SUNDAY NIGHT AS AN UP TIME FOR STORMS WITH MORE WIDESPREAD
CONVECTION. ON THE LARGER SCALE...POSITIONING OF THE HIGH CENTER BY
EARLY IN THE WEEK OPENS THE DOOR EVEN FURTHER FOR A DEEPER SOUTHERLY
FLOW. EXPECT HEAVIER RAINFALL RATES AS WE GET INTO THE DEEPER
MOISTURE. M

.TWC...NONE.

In the hours before

Local storm report, Jul 12, 5:32 PM MST, 1 hour 41 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TUCSON ARIZONA
0532 PM MST FRI JUL 12 2002

TIME (MST) .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0454 PM    SAFFORD                   AZ   69 MPH TSTM GUST
07/12/02   GRAHAM                         SAFFORD AIRPORT

0525 PM    DUNCAN                    AZ   WIND DAMAGE
07/12/02   GREENLEE                       SHINGLES BLOWN OFF HOUSE

The office that day

Everything else NWS Tucson, AZ issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 12, 5:02 PM MST	Severe Thunderstorm Warning	TWC	Graham	28 min
Jul 12, 6:12 PM MST	Severe Thunderstorm Warning	TWC	Pinal	28 min
Jul 12, 6:14 PM MST	Severe Thunderstorm Warning	TWC	Pinal	26 min
Jul 12, 7:23 PM MST	Severe Thunderstorm Warning	TWC	Cochise, Pima	27 min
Jul 13, 3:59 PM MST	Severe Thunderstorm Warning	TWC		46 min
Jul 13, 4:20 PM MST	Severe Thunderstorm Warning	TWC	Pima	40 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2002 Every severe thunderstorm warning in 2002

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.