Alert archive / Arizona / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 77, NWS Phoenix, AZ
NWS Phoenix, AZ issued this severe thunderstorm warning at Aug 30, 1997, 4:21 PM MST for Maricopa County, Arizona. It was in force for 49 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
- Aug 30, 1997, 4:21 PM MST (23:21 UTC)
- Expired
- Aug 30, 1997, 5:10 PM MST
- In force
- 49 min
- Issued by
- NWS Phoenix, AZ
- Area
- Whole counties
County Maricopa County, AZ
The radar
The Phoenix radar (KIWA), 77 km from the middle of the area, began a volume at 23:23 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, 11.4 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.
- Mixed-layer CAPE
- 263 J/kg
- Mixed-layer CIN
- -109 J/kg
- Mixed-layer LCL
- 1642 m above ground
- 0-6 km bulk shear
- 12 kt
- 0-1 km storm-relative helicity
- -27 m²/s²
- 0-3 km storm-relative helicity
- 13 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000
TTAA00 KPHX 302320 RRA
SVRPHX
AZC013-310010-
BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
421 PM MST SAT AUG 30 1997
* SEVERE THUNDERSTORM WARNING FOR
NORTH CENTRAL MARICOPA COUNTY IN CENTRAL ARIZONA
* UNTIL 510 PM MST
* SOME LOCATIONS AFFECTED
NEW RIVER
LAKE PLEASANT RECREATIONAL AREA
* AT 420 PM MST RADAR INDICATED A SEVERE THUNDERSTORM
EXTENDING FROM NEW RIVER TO 10 MILES NORTH OF SUN CITY.
MOVEMENT WAS TO THE NORTHEAST AT 10 TO 15 MPH.
DAMAGING WINDS IN EXCESS OF 57 MPH...HAIL GREATER THAN 3/4 INCH
IN DIAMETER...AND VERY HEAVY RAIN ARE LIKELY WITH THIS STORM.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 30, 3:18 PM MST, 1 hour 3 minutes before
AZZ020>025-CAZ030>033-311130- SEVERE WEATHER OUTLOOK NATIONAL WEATHER SERVICE PHOENIX AZ 245 PM MST/PDT SAT AUG 30 1997 ...A FLASH FLOOD WATCH IS IN EFFECT FOR MUCH OF ARIZONA UNTIL 9 PM MST... ...MODERATE RISK OF SEVERE THUNDERSTORMS OVER MARICOPA AND NORTHWEST PINAL COUNTIES THIS AFTERNOON AND TONIGHT... ...SLIGHT RISK OF SEVERE THUNDERSTORMS OVER LA PAZ...SOUTHERN GILA...AND FAR NORTHERN YUMA COUNTIES THIS AFTERNOON AND TONIGHT... OUTFLOWS FROM THUNDERSTORMS OVER NORTHWEST AND SOUTHEAST ARIZONA ARE ANTICIPATED TO MOVE INTO MARICOPA AND NORTHWEST PINAL COUNTIES THIS EVENING...AND GENERATE THUNDERSTORMS WHICH COULD PRODUCE VERY HEAVY RAINFALL IN EXCESS OF 1 INCH PER HOUR...WHICH COULD LEAD TO FLOODING OF STREETS AND WASHES..AND DAMAGING WINDS. IF ANY SEVERE STORMS FORM...THEY WILL MOST LIKELY OCCUR BETWEEN 5 PM AND 10 PM. THE PRIMARY THREAT FROM THUNDERSTORMS OVER LA PAZ...SOUTHERN GILA...AND FAR NORTHERN YUMA COUNTIES WILL BE HEAVY RAIN IN EXCESS OF 1 INCH PER HOUR WHICH COULD LEAD TO FLOODING OF STREETS OR WASHES. THE STORMS WILL LIKELY PRODUCE WINDS GUSTS TO NEAR 50 MPH...ALSO. THE THREAT OF SEVERE WEATHER IN THESE COUNTIES ARE EXPECTED TO END BY 9 PM. THE AIR MASS OVER THE SOUTHWEST U.S. HAS BECOME QUITE MOIST AND UNSTABLE ...THUS THERE IS A THREAT OF THUNDERSTORMS FORMING ANYWHERE IN THE OUTLOOK AREA. HOWEVER...OUTSIDE THE AREAS WHERE THERE IS A RISK OF SEVERE THUNDERSTORMS...ONLY ISOLATED THUNDERSTORMS WITH STRONG WINDS TO NEAR 50 MPH...DENSE BLOWING DUST OR SAND...AND BRIEF HEAVY RAIN ARE EXPECTED. .................................................................... FOR PURPOSES OF THIS OUTLOOK...SEVERE WEATHER REFERS TO ANY OF THE FOLLOWING...DAMAGING WINDS IN EXCESS OF 57 MPH...HAIL 3/4 INCH IN DIAMETER OR LARGER...AND LOCALLY HEAVY RAINFALL WHICH RESULTS IN RUNNING WASHES OR FLOODING. THE OUTLOOK AREA INCLUDES THE FOLLOWING COUNTIES... IN ARIZONA IN CALIFORNIA MARICOPA IMPERIAL SOUTHERN GILA CENTRAL/EASTERN RIVERSIDE NORTHWEST PINAL YUMA LA PAZ ....................................................................
The office that day
Everything else NWS Phoenix, AZ issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 30, 4:44 PM MST | Flash Flood Warning | PSR | La Paz | 61 min |
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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.