Alert archive / Arizona / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 1, NWS Tucson, AZ

June 20, 2001Pima County, Arizona

NWS Tucson, AZ issued this severe thunderstorm warning at Jun 20, 2001, 5:52 PM MST for Pima County, Arizona. It was in force for 38 min. 1 report came from inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties, with what was reported inside it.

The facts

Issued
Jun 20, 2001, 5:52 PM MST (00:52 UTC)
Expired
Jun 20, 2001, 6:30 PM MST
In force
38 min
Issued by
NWS Tucson, AZ
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Pima County, AZ

What was reported inside it

TimeReportWhereRemark
Jun 20, 5:55 PM MSTThunderstorm WindTucson, 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 00:00Z, 0.9 hours before the alert went out and 9 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 00:00Z on 2001-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 879 joules per kilogram.LCLEL10008507005003002001001 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 00:00Z on 2001-06-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -6 square meters per square second.1939Sfc1 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
879 J/kg
Mixed-layer CIN
-6 J/kg
Mixed-layer LCL
3149 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
-6 m²/s²
0-3 km storm-relative helicity
52 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.8

Open this sounding in Storm Lab

The text

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

000 
WUUS55 KTWC 210053
SVRTUS

AZC019-210130-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TUCSON AZ
552 PM MST WED JUN 20 2001

THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EAST CENTRAL PIMA COUNTY IN ARIZONA
  THIS INCLUDES CITY OF TUCSON

* UNTIL 630 PM MST

* AT 545 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 7 MILES NORTHEAST OF TUCSON...MOVING NORTHEAST 
  AT 20 MPH.

REMEMBER...A SEVERE THUNDERSTORM CAN PRODUCE LARGE HAIL...DAMAGING
WINDS IN EXCESS OF 55 MPH...DEADLY LIGHTNING...AND HEAVY RAIN.

LAT...LON 3226 11109 3208 11092 3226 11063 3238 11079

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 20, 2:55 PM MST, 2 hours 57 minutes earlier.

Area forecast discussion, Jun 20, 2:55 PM MST, 2 hours 57 minutes before
SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
255 PM MST WED JUN 20 2001

SYNOPSIS...HIGH PRESSURE HAS FOUND ITS HOME OVER SOUTHERN ARIZONA
AND WILL REMAIN OVER THE STATE FOR AT LEAST THE NEXT SEVERAL DAYS.
MOISTURE WORKING ITS WAY WEST ALONG THE MEXICO BORDER WILL CONTINUE
TO PROVIDE THE FUEL FOR AFTERNOON THUNDERSTORMS EACH DAY THIS WEEK.

DISCUSSION...PRECIPITABLE WATER VALUES REMAIN QUITE GOOD ACROSS THE
CWA TODAY. SOUNDINGS INDICATE 1.17 IN IN TUCSON...1.11 IN PHOENIX
AND 1.09 IN IN YUMA. THE TONGUE OF MOISTURE BETWEEN TUCSON AND YUMA
DEPICTED WELL ON GOES IMAGERY. THE 12Z ETA IS THE MODEL OF CHOICE
TODAY. IT APPEARS TO HAVE A BETTER HANDLE ON THE VORTICITY FIELD
WHEN OVERLAID ATOP OF THE H20 VAPOR IMAGE.

STILL LOOKS LIKE BEST ACTIVITY THIS EVENING WILL OCCUR TO THE SE OF
TUCSON WHERE A WEAK COL IN THE 700 MB FLOW WILL OPEN UP. THIS IS
ALSO SEEN IN THE ETA H7 OMEGA FIELD. STILL AM WAVERING WHETHER TO
PUT ISOLATED OR SCATTERED WORDING OUT EAST FOR TONIGHT.

EXPECT A SLIGHT RAMP UP IN THUNDERSTORM ACTIVITY LATE THU AFTERNOON
AND EVENING OVER SE AZ. THE ETA HAS A H3 SPEED DIVERGENCE MAX OVER
SONORA BY 00Z FRI...THEN PUSHES NORTHWARD INTO THE SOUTHERN FRINGES
OF OUR CWA BY 06Z. CURRENT MOISTURE ACROSS THE REGION SHOULD STICK
AROUND FOR TOMORROW...HELPING TO FUEL STORM DEVELOPMENT.
OTHERWISE...THE H5 RIDGE WILL CONTINUE TO BUILD NORTHWARD THROUGH
TOMORROW AND THEN SHIFT EAST FRIDAY...IN RESPONSE TO A UPPER LOW
MOVING INTO THE PACIFIC NORTHWEST. THIS WILL ALLOW FOR A FAVORABLE
SOUTHEAST FLOW TO PUSH ADDITIONAL MOISTURE INTO THE CWA THIS
WEEKEND. WILL OPT TO KEEP THE MENTION OF AFTERNOON AND EVENING
THUNDERSTORMS IN FAR SE AZ THRU MID NEXT WEEK. TEMPERATURES WILL
CONTINUE TO BE MODERATED BY THE INCREASED MOISTURE IN THE REGION...
THEREFORE NOT MUCH CHANGE IN TEMPS THROUGH WED.

.TWC...NONE.

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 20, 6:32 PM MSTSevere Thunderstorm WarningTWCPima43 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2001Every severe thunderstorm warning in 2001

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.