Alert archive / Arizona / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 20, NWS Tucson, AZ

July 19, 2001Pima County, Arizona

NWS Tucson, AZ issued this severe thunderstorm warning at Jul 19, 2001, 4:20 PM MST for Pima County, Arizona. It was in force for 40 min. No storm report in the archive falls 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.

The facts

Issued
Jul 19, 2001, 4:20 PM MST (23:20 UTC)
Expired
Jul 19, 2001, 5:00 PM MST
In force
40 min
Issued by
NWS Tucson, AZ
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Pima County, AZ

The nearest sounding before it

Tuscon, AZ (KTUS), launched 12:00Z, 11.3 hours before the alert went out and 29 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 2001-07-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 235 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 2001-07-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -16 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
235 J/kg
Mixed-layer CIN
-182 J/kg
Mixed-layer LCL
1932 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
-16 m²/s²
0-3 km storm-relative helicity
10 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
WUUS55 KTWC 192321
SVRTUS

AZC019-200000-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TUCSON AZ
420 PM MST THU JUL 19 2001

THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHEAST PIMA COUNTY IN ARIZONA
  THIS INCLUDES AREAS EAST OF GREEN VALLEY AND SAHUARITA

* UNTIL 500 PM MST

* AT 416 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 7 MILES NORTHEAST OF GREEN VALLEY...MOVING     
  NORTHEAST AT 10 MPH. FLASH FLOOD WARNING IS IN EFFECT FOR THE SAME 
  AREA UNTIL 515 PM MST.


REMEMBER...A SEVERE THUNDERSTORM CAN PRODUCE LARGE HAIL...DAMAGING
WINDS IN EXCESS OF 58h MPH...DEADLY LIGHTNING...AND HEAVY RAIN.

LAT...LON 3178 11110 3178 11083 3214 11083 3213 11109

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 19, 2:30 PM MST, 1 hour 50 minutes earlier.

Area forecast discussion, Jul 19, 2:30 PM MST, 1 hour 50 minutes before
SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
230 PM MST THU JUL 19 2001

SYNOPSIS...SOUTHEAST ARIZONA WILL REMAIN UNDER A MOIST FLOW FROM THE
SOUTH. THIS WILL RESULT IN AFTERNOON AND EVENING THUNDERSTORMS.
THERE MAY BE SOME INCREASE IN THE THUNDERSTORM ACTIVITY LATER IN THE
WEEKEND.

DISCUSSION...A LITTLE QUICKER...AND MORE SOUTHWESTERLY FLOW TODAY
BUT STORMS JUST IN ABOUT THE SAME POSITION AS YESTERDAY. SO WILL
CONTINUE TREND OF PREVIOUS FORECAST AND HAVE US IN A STANDARD
MONSOON PACKAGE NEXT FEW DAYS. EXPECTING A FAIRLY BIG BLAST IN
NORTHERN MEXICO TONIGHT WHICH MAY RESULT IN LOW LEVEL OUTFLOW
WORKING INTO AREA BUT NOT EXPECTING A SURGE. THUNDERSTORM COMPLEX
NEAR MMGM LOOKS OUT OF PLACE...RARE TO SEE SOMETHING THAT CLOSE TO
THE COAST BUT MAY BE A RESULT OF LAST NIGHTS CONVECTION.

MODELS HINT AT MORE ESTABLISHED EASTERLY FLOW OVER THE WEEKEND AND
TROPICAL WAVE NEAR 100 WEST MAY HAVE A CHUNK MOVE UP THIS WAY SUNDAY
OR SO.

.TWC...NONE.

In the hours before

Special weather statement, Jul 19, 11:06 AM MST, 5 hours 14 minutes before
AZZ019-029>035-200700-

SOUTHEAST ARIZONA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1145 AM MST THU JUL 19 2001

.SYNOPSIS...SOUTHEAST ARIZONA WILL REMAIN IN THE DEEP MONSOONAL
MOISTURE THIS AFTERNOON AND EVENING...WHILE OTHER ADJACENT PORTIONS
OF THE STATE STAY RELATIVELY DRY. EXCEPT FOR A POSSIBLE EARLIER
START TO CONVECTION...ENVIRONMENTAL CONDITIONS ARE SIMILIAR TO
WEDNESDAY. THEREFORE EXPECT A LOCALIZED THREAT OF SEVERE WEATHER AND
FLASH FLOODING.

.DISCUSSION...12Z TUCSON SOUNDING SIMILIAR TO WEDNESDAY...EXCEPT NO
CAP TO SLOW THUNDERSTORM DEVELOPMENT. THIS TRANSLATES INTO AN
EARLIER START TIME FOR CONVECTION...ALREADY EVIDENT ON
RADAR/SATELLITE IMAGERY. LOW LEVEL DEWPOINT/THETA E VALUES SHOW A
CONTINUED THREAT OF LOCALIZED FLASH FLOODING. AS SEEN YESTERDAY IN
TUCSON...THE POTENTIAL ALSO EXISTS FOR WET MICROBURSTS IN MERGING
STORMS WITH WIND GUSTS IN EXCESS OF 60 MPH. STORM MOVEMENT WILL BE A
LITTLE BIT FASTER TODAY...TO THE NORTH AROUND 10 MPH.

THERE IS NO DISCERNABLE SYNOPTIC SCALE FEATURE TO ORGANIZE
CONVECTION ACROSS SOUTHEAST ARIZONA TODAY. THERE IS GOOD 300 MB
DIVERGENCE AND OMEGA OVER NORTHWEST MEXICO THIS EVENING FOR MCS
DEVELOPMENT...THEREFORE SHOULD GET AN INFLUX OF LOW LEVEL
MOISTURE INTO FAR SOUTHEAST ARIZONA FROM OUTFLOW BOUNDARIES
OVERNIGHT.

OKULSKI
Special weather statement, Jul 19, 11:45 AM MST, 4 hours 35 minutes before
AZZ019-029>035-200700-

SOUTHEAST ARIZONA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1145 AM MST THU JUL 19 2001

.SYNOPSIS...SOUTHEAST ARIZONA WILL REMAIN IN THE DEEP MONSOONAL
MOISTURE THIS AFTERNOON AND EVENING...WHILE OTHER ADJACENT PORTIONS
OF THE STATE STAY RELATIVELY DRY. EXCEPT FOR A POSSIBLE EARLIER
START TO CONVECTION...ENVIRONMENTAL CONDITIONS ARE SIMILIAR TO
WEDNESDAY. THEREFORE EXPECT A LOCALIZED THREAT OF SEVERE WEATHER AND
FLASH FLOODING.

.DISCUSSION...12Z TUCSON SOUNDING SIMILIAR TO WEDNESDAY...EXCEPT NO
CAP TO SLOW THUNDERSTORM DEVELOPMENT. THIS TRANSLATES INTO AN
EARLIER START TIME FOR CONVECTION...ALREADY EVIDENT ON
RADAR/SATELLITE IMAGERY. LOW LEVEL DEWPOINT/THETA E VALUES SHOW A
CONTINUED THREAT OF LOCALIZED FLASH FLOODING. AS SEEN YESTERDAY IN
TUCSON...THE POTENTIAL ALSO EXISTS FOR WET MICROBURSTS IN MERGING
STORMS WITH WIND GUSTS IN EXCESS OF 60 MPH. STORM MOVEMENT WILL BE A
LITTLE BIT FASTER TODAY...TO THE NORTH AROUND 10 MPH.

THERE IS NO DISCERNABLE SYNOPTIC SCALE FEATURE TO ORGANIZE
CONVECTION ACROSS SOUTHEAST ARIZONA TODAY. THERE IS GOOD 300 MB
DIVERGENCE AND OMEGA OVER NORTHWEST MEXICO THIS EVENING FOR MCS
DEVELOPMENT...THEREFORE SHOULD GET AN INFLUX OF LOW LEVEL
MOISTURE INTO FAR SOUTHEAST ARIZONA FROM OUTFLOW BOUNDARIES
OVERNIGHT.

OKULSKI

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 19, 4:17 PM MSTFlash Flood WarningTWCPima

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; the sounding from the Mesonet's radiosonde archive.