Alert archive / Arizona / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 29, NWS Phoenix, AZ

August 6, 1990Maricopa County, Arizona

NWS Phoenix, AZ issued this severe thunderstorm warning at Aug 6, 1990, 9:30 PM MST for Maricopa County, Arizona. It was in force for 50 min.

The area

The counties it named.

The facts

Issued
Aug 6, 1990, 9:30 PM MST (04:30 UTC)
Expired
Aug 6, 1990, 10:20 PM MST
In force
50 min
Issued by
NWS Phoenix, AZ
Area
Whole counties

County Maricopa County, AZ

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Tuscon, AZ (KTUS), launched 00:00Z, 4.5 hours before the alert went out and 198 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 1990-08-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 1990-08-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -4 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1966 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
-4 m²/s²
0-3 km storm-relative helicity
-4 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.

In the hours before

Special weather statement, Aug 6, 9:03 PM MST, 27 minutes before
AZZALL-070500-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PHOENIX AZ
900 PM MST MON AUG 6 1990

...THUNDERSTORMS WITH HEAVY RAIN MOVING TOWARDS THE GREATER PHOENIX
AREA FROM THE EAST...

ANOTHER GROUP OF THUNDERSTORMS WERE SLOWLY DEVELOPING OVER THE DISTANT
MOUNTAINS NORTHEAST AND EAST OF PHOENIX THIS EVENING.  AFTER 7PM A
FEW THUNDERSTORMS WITH HEAVY RAIN WERE DETECTED BY RADAR NEAR PAYSON.
HOWEVER AFTER 845 PM THESE STORMS EXPANDED IN COVERAGE AND EXTEND
FROM NEAR PAYSON...SOUTH THROUGH LAKE ROOSEVELT... TO APACHE
JUNCTION.

THUNDERSTORMS ARE EXPECTED TO HOLD TOGETHER AND MOVE INTO THE EASTERN
VALLEYS OF THE GREATER PHOENIX AREA AFFECTING  MESA...CHANDLER...
SCOTTSDALE... AND PERHAPS EVENTUALLY INTO THE PHOENIX METRO AREA.

STRONG WINDS TO 50 MPH...HEAVY RAIN...DEADLY LIGHTNING...AND LOCAL
FLOODING ARE ALL THUNDERSTORMS HAZARDS.

THE WEATHER WILL BE MONITORED FOR POSSIBLE WEATHER WATCHES OR WARNINGS.

VASQUEZ

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 6, 5:25 PM MSTFlash Flood WarningPSRMaricopa75 min
Aug 6, 5:25 PM MSTSevere Thunderstorm WarningPSRMaricopa75 min
Aug 6, 5:25 PM MSTSevere Thunderstorm WarningPSRMaricopa110 min
Aug 6, 9:30 PM MSTSevere Thunderstorm WarningPSRMaricopa60 min

Nearby

Severe Thunderstorm Warnings in Arizona, 1990Every severe thunderstorm warning in 1990

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.