Alert archive / Arizona / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 59, NWS Tucson, AZ

August 28, 2002Cochise County, Arizona

NWS Tucson, AZ issued this severe thunderstorm warning at Aug 28, 2002, 2:09 PM MST for Cochise County, Arizona. It was in force for 51 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
Aug 28, 2002, 2:09 PM MST (21:09 UTC)
Expired
Aug 28, 2002, 3:00 PM MST
In force
51 min
Issued by
NWS Tucson, AZ
Area
Counties, with a storm outline in the text

County Cochise County, AZ

The radar

The Tucson radar (KEMX), 34 km from the middle of the area, began a volume at 21:10 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 12:00Z, 9.2 hours before the alert went out and 56 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-pSkew-T log-p diagram, Tuscon, AZ at 12:00Z on 2002-08-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3633 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Tuscon, AZ at 12:00Z on 2002-08-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 75 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
3633 J/kg
Mixed-layer CIN
-104 J/kg
Mixed-layer LCL
1518 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
75 m²/s²
0-3 km storm-relative helicity
68 m²/s²
Significant tornado parameter
0.0
Supercell composite
7.0

Open this sounding in Storm Lab

The text

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

223 
WUUS55 KTWC 282109
SVRTWC
AZC003-282200-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TUCSON AZ
208 PM MST WED AUG 28 2002

THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WEST CENTRAL COCHISE COUNTY IN ARIZONA

* UNTIL 300 PM MST

* AT 200 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 6 MILES WEST OF BENSON...OR ABOUT 30 MILES
  NORTH OF SIERRA VISTA...MOVING NORTHEAST AT 20 MPH.

LARGE HAIL IS LIKELY. PUT YOUR VEHICLE IN A GARAGE OR CARPORT AND
MOVE TO A STURDY SHELTER.

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS IN EXCESS OF 55 MPH...
HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. MOVE TO AN INTERIOR
ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. HEAVY RAINS FLOOD
ROADS QUICKLY SO DO NOT DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

LAT...LON 3206 11044 3187 11044 3204 11006 3224 11024

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 Aug 28, 9:45 AM MST, 4 hours 24 minutes earlier.

Area forecast discussion, Aug 28, 9:45 AM MST, 4 hours 24 minutes before
SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
945 AM MST WED AUG 28 2002

.SYNOPSIS...AN INCREASE IN MOISTURE ACROSS SOUTHEAST ARIZONA WILL
BRING A SLOW INCREASE IN AFTERNOON AND EVENING THUNDERSTORM ACTIVITY
THE REST OF THE WEEK AND INTO THE COMING WEEKEND. AS A
RESULT...AFTERNOON HIGH TEMPERATURES WILL FALL A FEW DEGREES.

.DISCUSSION...LOOKING AT IR IMAGERY...WE STILL HAVE SOME CLOUD
DEBRIS ACROSS SOUTHEAST ARIZONA FROM LAST NIGHTS THUNDERSTORM
COMPLEX THAT DEVELOPED IN MEXICO.  A FEW LIGHTNING STRIKES HIT IN
COCHISE AND SANTA CRUZ AROUND MIDNIGHT...HOWEVER MOST ACTIVITY WAS
ALONG AND SOUTH OF THE U.S. AND MEXICAN BORDER.  WITH LOWER LEVEL
WINDS FROM SOUTH AND SOUTHWEST...SIGNIFICANT MOISTURE WAS PULLED UP
FROM THE COMPLEX INTO EXTREME SOUTHEAST ARIZONA...FROM TUCSON EAST.
AS A RESULT OF MOISTURE INCREASE AND CLOUD COVER...LOW TEMPERATURES
ACROSS THE AREA WERE 10 DEGREES ABOVE THE PREVIOUS NIGHTS LOW TEMPS.
WITH THE HIGHER HUMIDITIES ACROSS THE AREA (CURRENTLY 47 PERCENT
FROM YESTERDAYS 20 PERCENT)....TEMPERATURES MAY NOT BE AS HIGH AS
THE LAST COUPLE OF DAYS. PREVIOUS SHIFT DROPPED TEMPERATURES BACK
ABOUT 5 DEGREES ACROSS THE AREA FOR TODAY AND THIS LOOKS PRETTY
GOOD. CAN SEE THE SIGNIFICANT INCREASE IN MOISTURE BEST FROM THE 12Z
KTUS SOUNDING...WITH PWAT VALUES OF 1.75 INCHES (THE PREVIOUS
SOUNDING ONLY HAD .8 INCHES).  IN THE LOWEST LEVELS WE HAD 10 TO 20
KNOT SOUTHERLY WINDS HELPING PULL THE MOISTURE NORTHWARDS.
HOWEVER...THE YUMA AND PHOENIX SOUNDINGS WERE RATHER DRY.  THE PWAT
VALUES AT YUMA ONLY INCREASED FROM .62 TO .78 INCHES AND THE KPSR
ONLY INCREASED FROM .68 TO .81 INCHES...AND BOTH DRY IN THE LOWEST
LEVELS.  TAKING A LOOK AT YUMA VAD WIND PROFILER...THE WINDS WERE
PREDOMINATELY FROM THE WEST OR NORTHWEST FROM 2000 FEET AND UPWARD
WITH ONLY 10 TO 15 KNOTS FROM THE SOUTH BELOW 2000 FEET.  A RECENT
VAD WIND PROFILE INDICATED SLIGHT SURGING...WITH WINDS FROM THE
SOUTH AT 10 TO 20 KNOTS UP TO 3000 FEET.  SO THE BIG QUESTION FOR
THE DAY...ARE WE GOING TO GET SOME THUNDERSTORM DEVELOPMENT TODAY?
WITH THE JET MAX MOVING ACROSS THE AREA TODAY AND TOMORROW THERE
SHOULD BE SOME WEAK UPPER LEVEL FORCING. PLUS THERE IS ENOUGH
MOISTURE IN EXTREME PORTIONS OF SOUTHEAST ARIZONA...THAT MAY BE ABLE
TO FIRE SOME SORT OF CONVECTION.  THE ETA MODEL INDICATES THAT THE
UPPER LEVEL DIVERGENCE FIELD WOULD BE OVER CENTRAL ARIZONA AND SHOWS
PRECIP OVER EASTERN ARIZONA.   HOWEVER...THE AVN MODEL INDICATES A
MORE ISOLATED TO SCATTERED TYPE EVENT FOR THIS AFTERNOON...WITH THE
UPPER LEVEL DIVERGENCE FIELD OVER NEW MEXICO AREA WHERE IT IS
PREDICTING THE BEST AREA FOR THUNDERSTORM DEVELOPMENT.  CURRENTLY A
FEW THUNDERSTORMS HAVE ALREADY FIRED OVER WESTERN NEW MEXICO. FOR
NOW...CURRENTLY THINK THAT BEST CHANCES OF DEVELOPMENT WILL BE IN
THE WHITES AND EASTERN MOUNTAINS FOR THIS AFTERNOON AND EVENING. NOT
TOO CONFIDENT ABOUT THE 30 AND 40 POPS IN TUCSON AREA...MAY HAVE TO
MAKE AN UPDATE TO LOWER BY 10 PERCENT OR SO...BUT WOULD LIKE TO SEE
HOW THINGS DEVELOP. MG

.TWC...NONE.

In the hours before

Special weather statement, Aug 28, 11:30 AM MST, 2 hours 39 minutes before
AZZ019-029>035-290700-

SOUTHEAST ARIZONA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1130 AM MST WED AUG 28 2002

.SYNOPSIS...THE AIRMASS HAS MOISTENED SIGNIFICANTLY OVER NEARLY ALL
OF SOUTHEAST ARIZONA. EXTREME WESTERN SECTIONS OF THE AREA REMAIN
FAIRLY DRY UNDER THE INFLUENCE OF SOUTHWEST WINDS ALOFT. AN UPPER
HIGH PRESSURE CENTER WILL REMAIN OVER WEST TEXAS OR SOUTHERN NEW
MEXICO FOR THE NEXT SEVERAL DAYS. AN UPPER TROF HAS SETTLED INTO THE
INTERMOUNTAIN AREA AND THIS HAS CAUSED AN INCREASE IN THE SOUTHWEST
WINDS ALOFT OVER THE WESTERN SECTIONS OF THE STATE.

.DISCUSSION...THE LARGE INCREASE IN MOISTURE IS DUE TO A
THUNDERSTORM COMPLEX THAT DEVELOPED SOUTH OF COCHISE COUNTY LATE
TUESDAY. THE COMBINATION OF THE UPPER HIGH AND THE TROF IS CAUSING
FAIRLY BRISK SOUTHWEST WINDS ALOFT OVER THE AREA. THE AMOUNT OF
MOISTURE IN THE AIR WILL HELP TO PRODUCE VERY HEAVY RAIN FROM THESE
STORMS. HOWEVER THE STRONG SOUTHWEST WINDS WILL PUSH THE STORMS AT
GOOD CLIP TO THE NORTHEAST. THUS THE THREAT FOR HEAVY RAIN IS NEAR
CLIMATOLOGY VALUES. THE AMOUNT OF MOISTURE IN THE AIR WILL ALSO
CAUSE SKIES TO CLOUD OVER THUS PREVENTING STRONG HEATING. THIS WILL
HELP TO REDUCE THE LIKELIHOOD OF SEVERE WINDS FROM THESE STORMS.
HOWEVER COLD AIR ALOFT COULD INCREASE THE THREAT OF HAIL.
Special weather statement, Aug 28, 12:02 PM MST, 2 hours 7 minutes before
AZZ019-029>035-290700-

SOUTHEAST ARIZONA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1130 AM MST WED AUG 28 2002

.SYNOPSIS...THE AIRMASS HAS MOISTENED SIGNIFICANTLY OVER NEARLY ALL
OF SOUTHEAST ARIZONA. EXTREME WESTERN SECTIONS OF THE AREA REMAIN
FAIRLY DRY UNDER THE INFLUENCE OF SOUTHWEST WINDS ALOFT. AN UPPER
HIGH PRESSURE CENTER WILL REMAIN OVER WEST TEXAS OR SOUTHERN NEW
MEXICO FOR THE NEXT SEVERAL DAYS. AN UPPER TROF HAS SETTLED INTO THE
INTERMOUNTAIN AREA AND THIS HAS CAUSED AN INCREASE IN THE SOUTHWEST
WINDS ALOFT OVER THE WESTERN SECTIONS OF THE STATE.

.DISCUSSION...THE LARGE INCREASE IN MOISTURE IS DUE TO A
THUNDERSTORM COMPLEX THAT DEVELOPED SOUTH OF COCHISE COUNTY LATE
TUESDAY. THE COMBINATION OF THE UPPER HIGH AND THE TROF IS CAUSING
FAIRLY BRISK SOUTHWEST WINDS ALOFT OVER THE AREA. THE AMOUNT OF
MOISTURE IN THE AIR WILL HELP TO PRODUCE VERY HEAVY RAIN FROM THESE
STORMS. HOWEVER THE STRONG SOUTHWEST WINDS WILL PUSH THE STORMS AT
GOOD CLIP TO THE NORTHEAST. THUS THE THREAT FOR HEAVY RAIN IS NEAR
CLIMATOLOGY VALUES. THE AMOUNT OF MOISTURE IN THE AIR WILL ALSO
CAUSE SKIES TO CLOUD OVER THUS PREVENTING STRONG HEATING. THIS WILL
HELP TO REDUCE THE LIKELIHOOD OF SEVERE WINDS FROM THESE STORMS.
HOWEVER COLD AIR ALOFT COULD INCREASE THE THREAT OF HAIL.

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 28, 1:48 PM MSTSevere Thunderstorm WarningTWCPima42 min
Aug 28, 2:31 PM MSTSevere Thunderstorm WarningTWCPima29 min
Aug 28, 2:35 PM MSTSevere Thunderstorm WarningTWCPinal25 min
Aug 28, 3:12 PM MSTSevere Thunderstorm WarningTWCPima, Pinal48 min
Aug 28, 4:04 PM MSTSevere Thunderstorm WarningTWCPima41 min
Aug 28, 4:54 PM MSTFlash Flood WarningTWCPima3 hr
Aug 28, 4:55 PM MSTFlash Flood WarningTWCPima110 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2002Every 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.