Alert archive / Arizona / Flash Flood Warnings in 1997

Flash Flood Warning 56, NWS Tucson, AZ

September 21, 1997Cochise County, Arizona

NWS Tucson, AZ issued this flash flood warning at Sep 21, 1997, 12:56 PM MST for Cochise County, Arizona. It was in force for 94 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 21, 1997, 12:56 PM MST (19:56 UTC)
Expired
Sep 21, 1997, 2:30 PM MST
In force
94 min
Issued by
NWS Tucson, AZ
Area
Whole counties

County Cochise County, AZ

The radar

The Tucson radar (KEMX), 83 km from the middle of the area, began a volume at 19:57 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, 7.9 hours before the alert went out and 113 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 1997-09-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 393 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Tuscon, AZ at 12:00Z on 1997-09-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 113 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
393 J/kg
Mixed-layer CIN
-206 J/kg
Mixed-layer LCL
1697 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
113 m²/s²
0-3 km storm-relative helicity
193 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.3

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KTUS 211958
FFWTUS
AZC003-212130-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM AND FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE TUCSON AZ
1256 PM MST SUN SEP 21 1997

THE NATIONAL WEATHER SERVICE IN TUCSON AZ HAS ISSUED A
SEVERE THUNDERSTORM AND FLASH FLOOD WARNING EFFECTIVE UNTIL 230 PM
MST
FOR PEOPLE IN THE FOLLOWING LOCATION...

IN SOUTHEASTERN ARIZONA

   ...WESTERN COCHISE COUNTY
 
DOPPLER RADAR INDICATED A LINE OF STRONG THUNDERSTORMS FROM NEAR4
BENSON TO THE MEXICAN BORDER.  THE STRONGEST STORMS ARE CAPABLE OF
PRODUCING WIND GUSTS IN EXCESS OF 58 MPH...HAIL AND VERY HEAVY
RAINFALL.  STORM MOVEMENT WAS TO THE NORHTEAST AT 15 MPH.

What forecasters said that day

The local office's own words before this flash flood 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 flash flood warning went out at Sep 21, 9:16 AM MST, 3 hours 40 minutes earlier.

Area forecast discussion, Sep 21, 9:16 AM MST, 3 hours 40 minutes before
SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
900 AM MST SUN SEP 21 1997

MOST REPORTS OF RAINFALL OVER NIGHT HAVE BEEN LESS THAN .5 INCH...BUT
BISBEE REPORTED 1.4 AND ALPINE REPORTED 2.00 INCHES. GAGES ON THE
UPPER GILA RIVER SHOWING SOME RISES ALSO. RADAR STILL SHOWING LOTS OF
ECHOS IN ERN ZONES... BUT LOOKS LIKE LAST OF THE LINE IS MOVING
THROUGH COCHISE COUNTY AT THIS TIME. 12Z TUS SOUNDING SHOWS LOTS OF
LOW LEVEL COOLING. BUT CLOUDS CLEARING OUT OF TUS AREA AT THIS TIME.
AND DIURNAL HEATING ENOUGH FOR MORE TSTMS THIS AFTERNOON. LIKELY
STARTING LATE IN THE AFTERNOON THOUGH. GOES 9 SOUNDER DEW POINTS PUT
THE DEEPEST MOISTURE FROM ABOUT TUS EWD.   WILL LIKELY NEE`D TO UPDATE
ZONES LATER THIS MORNING. TUS 552.

TUS...NONE.

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 21, 2:08 AM MSTSevere Thunderstorm WarningTWCPima42 min
Sep 21, 4:03 AM MSTSevere Thunderstorm WarningTWCPima, Pinal67 min
Sep 21, 4:39 AM MSTSevere Thunderstorm WarningTWCGraham61 min
Sep 21, 7:35 AM MSTSevere Thunderstorm WarningTWCCochise, Pima30 min
Sep 21, 12:56 PM MSTSevere Thunderstorm WarningTWCCochise94 min
Sep 21, 2:16 PM MSTFlash Flood WarningTWCCochise64 min
Sep 21, 2:16 PM MSTSevere Thunderstorm WarningTWCCochise64 min
Sep 21, 2:28 PM MSTFlash Flood WarningTWCCochise, Graham62 min
Sep 21, 2:28 PM MSTSevere Thunderstorm WarningTWCCochise, Graham62 min
Sep 21, 3:33 PM MSTFlash Flood WarningTWCCochise62 min

Nearby

Flash Flood Warnings in Arizona, 1997Every flash flood 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.