Alert archive / Arizona / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 2, NWS Phoenix, AZ
NWS Phoenix, AZ issued this severe thunderstorm warning at May 20, 1997, 1:50 PM MST for Maricopa County, Pinal County, Arizona. It was in force for 70 min. 1 report came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- May 20, 1997, 1:50 PM MST (20:50 UTC)
- Expired
- May 20, 1997, 3:00 PM MST
- In force
- 70 min
- Issued by
- NWS Phoenix, AZ
- Area
- Whole counties
Counties Maricopa County, AZ, Pinal County, AZ
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| May 20, 2:30 PM MST | Thunderstorm Wind 52 | Mesa, AZ | Wind gust was estimated by a weather spotter at Apache Trail and Ellsworth Road. |
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 12:00Z, 8.8 hours before the alert went out and 143 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.
- Mixed-layer CAPE
- 24 J/kg
- Mixed-layer CIN
- -156 J/kg
- Mixed-layer LCL
- 1784 m above ground
- 0-6 km bulk shear
- 23 kt
- 0-1 km storm-relative helicity
- -4 m²/s²
- 0-3 km storm-relative helicity
- -7 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
808 WUUS1 KPHX 202053 RRA SVRPHX AZC013-021-202200- BULLETIN - EAS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE PHOENIX AZ 150 PM MST TUE MAY 20 1997 * SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN MARICOPA COUNTY IN CENTRAL ARIZONA NORTHEASTERN PINAL COUNTY IN CENTRAL ARIZONA * UNTIL 3 PM MST * SOME LOCATIONS AFFECTED QUEEN CREEK APACHE JUNCTION GILBERT * AT 145 PM MST RADAR INDICATED A LINE OF SEVERE THUNDERSTORMS EXTENDING FROM NEAR GILBERT EAST TO 10 MILES SOUTH OF SUPERIOR. MOVEMENT WAS TO THE NORTH AT 10 TO 15 MPH. * SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55 MPH... DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. BLOWING DUST COULD RESTRICT VISIBILITY TO LESS THAN 1 MILE AT TIMES. YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. RB
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, May 20, 12:28 PM MST, 1 hour 22 minutes before
AZZ023>025-210000- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE PHOENIX AZ 1228 PM MST TUE MAY 20 1997 ...SLIGHT RISK OF SEVERE THUNDERSTORMS OVER MARICOPA...NORTHWEST PINAL...AND SOUTHERN GILA COUNTIES THIS AFTERNOON AND TONIGHT... THUNDERSTORMS ARE LIKELY OVER THE SOUTHWEST AND CENTRAL DESERTS AS WELL AS SOUTHERN GILA COUNTY THIS AFTERNOON AND TONIGHT. THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS. THE GREATER PHOENIX METROPOLITAN AREA...CASA GRANDE...GLOBE...MIAMI...AND GILA BEND ARE IN THE SLIGHT RISK AREA. THE GREATEST RISK FROM STORMS WILL BE INTENSE LIGHTNING...POTENTIALLY DAMAGING WINDS AND BLOWING DUST...LOCALLY HEAVY RAIN...AND HAIL. AT MIDDAY...AN UPPER LEVEL DISTURBANCE IS CENTERED OVER THE NORTHERN GULF OF CALIFORNIA. THIS DISTURBANCE IS FORECAST TO MOVE SLOWLY NORTH ACROSS SOUTHERN ARIZONA LATER THIS AFTERNOON AND TONIGHT. IN ADVANCE OF THIS DISTURBANCE...THE ATMOSPHERE OVER SOUTH-CENTRAL ARIZONA IS ALREADY UNSTABLE AND CONTINUES TO DESTABILIZE. THUNDERSTORMS HAVE DEVELOPED OVER PORTIONS OF MARICOPA AND PINAL COUNTIES...AND ARE EXPECTED TO INCREASE IN INTENSITY AND AREAL COVERAGE THIS AFTERNOON AND TONIGHT. INDIVIDUAL STORMS WILL MOVE TOWARD THE NORTH AT 10 TO 15 MPH. DG/BE
Nearby
Severe Thunderstorm Warnings in Arizona, 1997Every 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.