Alert archive / Arizona / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 106, NWS Tucson, AZ

September 15, 1997Pinal County, Arizona

NWS Tucson, AZ issued this severe thunderstorm warning at Sep 15, 1997, 2:00 PM MST for Pinal County, Arizona. It was in force for 60 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Sep 15, 1997, 2:00 PM MST (21:00 UTC)
Expired: Sep 15, 1997, 3:00 PM MST
In force: 60 min
Issued by: NWS Tucson, AZ
Area: Whole counties

County Pinal County, AZ

The radar

The Phoenix radar (KIWA), 52 km from the middle of the area, began a volume at 21:00 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.

The nearest sounding before it

Tuscon, AZ (KTUS), launched 12:00Z, 9.0 hours before the alert went out and 92 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: 419 J/kg
Mixed-layer CIN: -173 J/kg
Mixed-layer LCL: 1485 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 13 m²/s²
0-3 km storm-relative helicity: 51 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

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 Sep 15, 9:16 AM MST, 4 hours 44 minutes earlier.

Area forecast discussion, Sep 15, 9:16 AM MST, 4 hours 44 minutes before

SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
915 AM MST MON SEP 15 1997

PLENTY OF MOISTURE IN CWA WITH HIGHEST MOISTURE TO THE WEST. PROBLEM
IS IF WE CAN GET STORMS GOING DOWN HERE. MODIFIED TUS SOUNDING FOR A
HIGH OF 96 GIVES CAPE NEAR 1000 BUT STILL SOME CIN...WILL NEED
SOMETHING TO BREAK THE CAP. IF DECENT MOUNTAIN STORMS FORM THIS WILL
CREATE OUTFLOW NEEDED TO GET THINGS GOING IN THE VALLEYS...AND THE
STORMS WILL HAVE THE DESIRE TO REFORM TOWARD THE WEST IN SEARCH OF
THE HIGHER THETA-E AIR. DYNAMICS SOMEWHAT LACKING TODAY...12Z ETA
SHOWS A WEAK VORT MOVING ACROSS CENTRAL AZ THIS MORNING AND THIS IS
SETTING OFF A FEW STORMS. NOTHING DOING FOR THE REST OF THE DAY
UNTIL TONIGHT...WHEN THE SHEAR INCREASES. ALL THIS POINTS TO LATE
AFTERNOON ACTIVITY GOING WELL INTO THE NIGHT...AS PER THE CURRENT
FORECAST. TUS 343. LUDWIG

TUS...NONE.

In the hours before

Special weather statement, Sep 15, 11:48 AM MST, 2 hours 12 minutes before

AZZ019-026>030-152300-
SPECIAL WEATHER STATEMENT...SOUTHEAST ARIZONA CONVECTIVE OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1145 AM MST MON SEP 15 1997...THIS PRODUCT IS NOT UPDATED

                AREAL    PROBABILITY   RAIN GREATER THAN   STORM
              COVERAGE    OF SEVERE     1.00       2.00    MOTION

COCHISE          30          30          30         10      NE 10
GRAHAM           40          30          40         20      NE 10
GREENLEE         40          30          40         20      NE 10
TUCSON/ERN PIMA  30          35          50         25      NE 12
TOHONO OODHAM   40          30          60         30      NE 15
WESTERN PIMA     40          30          60         30      NE 15
SOUTHEAST PINAL  30          30          45         25      NE 12
SANTA CRUZ       40          40          60         30      NE 10

SYNOPSIS...ABUNDANT MOISTURE LIES OVER THE AREA...WITH THE HIGHEST
MOISTURE VALUES TO THE WEST AND LOWER VALUES TO THE EAST. HEAVY RAIN
IS THE BIGGEST THREAT WITH THESE STORMS AS THEY THRIVE ON DEEP
MOISTURE...ESPECIALLY FROM TUCSON WESTWARD.
*****************************************************************
KEY...
AREAL COVERAGE - PERCENT OF COUNTY OR AREA THAT WILL EXPERIENCE
                  THUNDERSTORMS
PROB OF SEVERE - THE PROBABILITY THAT ANY ONE OF THE STORMS WILL
                  REACH SEVERE LEVELS (DAMAGING WIND AND/OR
                  LARGE HAIL)
RAIN GRTR THAN - THE PROBABILITY THAT ANY ONE OF THE STORMS 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 NOON 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.

END/LUDWIG

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 15, 2:00 PM MST	Flash Flood Warning	TWC	Pinal	60 min
Sep 15, 3:09 PM MST	Flash Flood Warning	TWC	Pima	61 min
Sep 15, 4:25 PM MST	Flash Flood Warning	TWC	Cochise	90 min

Nearby

Severe Thunderstorm Warnings in Arizona, 1997 Every severe thunderstorm warning in 1997

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.