Alert archive / Arizona / Flash Flood Warnings in 1998

Flash Flood Warning 29, NWS Tucson, AZ

July 23, 1998Pima County, Arizona

NWS Tucson, AZ issued this flash flood warning at Jul 23, 1998, 9:45 PM MST for Pima County, Arizona. It was in force for 90 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
Jul 23, 1998, 9:45 PM MST (04:45 UTC)
Expired
Jul 23, 1998, 11:15 PM MST
In force
90 min
Issued by
NWS Tucson, AZ
Area
Whole counties

County Pima County, AZ

The radar

The Tucson radar (KEMX), 112 km from the middle of the area, began a volume at 04:48 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 00:00Z, 4.8 hours before the alert went out and 84 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 1998-07-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 807 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 00:00Z on 1998-07-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 7 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
807 J/kg
Mixed-layer CIN
-12 J/kg
Mixed-layer LCL
1736 m above ground
0-6 km bulk shear
4 kt
0-1 km storm-relative helicity
7 m²/s²
0-3 km storm-relative helicity
25 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KTUS 240447
FFWTUS
AZC019-240615-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE TUCSON AZ
945 PM MST THU JUL 23 1998

THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EASTERN PIMA COUNTY IN SOUTHERN ARIZONA

* UNTIL 1115 PM MST

* AT 943 PM MST... NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  A THUNDERSTORM WITH VERY HEAVY RAIN OVER MARANA... MOVING SLOWLY
  EAST. RADAR INDICATED UP TO 2 INCHES OF RAIN HAS FALLEN FROM
  THIS STORM IN THE PAST HOUR.



  CEC

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 Jul 23, 2:00 PM MST, 7 hours 45 minutes earlier.

Area forecast discussion, Jul 23, 2:00 PM MST, 7 hours 45 minutes before
SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
200 PM MST THU JUL 23 1998

SYNOPSIS...HIGH PRESSURE ALOFT WILL SINK SOUTHWARD INTO SOUTHERN NEW
MEXICO THROUGH THE END OF THIS WEEK. A MAINLY SOUTH FLOW WILL ALLOW
MONSOONAL MOISTURE TO CONTINUE TO MOVE INTO SOUTHEAST ARIZONA. THE
HIGH ALOFT IS EXPECT DRIFT WESTWARD OVER ARIZONA EARLY NEXT WEEK.
THIS WILL DRY OUT WESTERN ARIZONA WITH TYPICAL AFTERNOON AND EVENING
THUNDERSTORMS CONTINUING INTO THE EASTERN PORTION OF THE STATE.

DISCUSSION...AS EXPECTED IT DID NOT TAKE MUCH CLEARING AND DAYTIME
HEATING FOR THUNDERSTORMS TO DEVELOP. THE GREATEST AMOUNT OF
ACTIVITY THUS FAR HAS BEEN IN COCHISE COUNTY. STORMS WERE MOVING TO
THE NORTHEAST. HEAVY RAIN AND LOCALIZED FLOODING WILL BE THE PRIMARY
HAZARDS THROUGH THE EVENING HOURS.

THE ETA MODEL GUIDANCE TAKES HIGH PRESSURE ALOFT TO SOUTHWEST MEXICO
BY SATURDAY MORNING. THE FLOW ALOFT REMAINS FAVORABLE FOR THE IMPORT
OF MONSOONAL MOISTURE...PARTICULARLY FROM TUCSON EASTWARD. SHOULD
SEE A RETURN TO A MORE TYPICAL AFTERNOON/EVENING THUNDERSTORM CYCLE
WITH TIME. 500 MB HEIGHTS RISE DURING THE PERIOD FOR WARMER
TEMPERATURES.

THE HIGH ALOFT DRIFTS OVER THE STATE EARLY NEXT WEEK WHICH CUTS OFF
MOST OF THE IMPORT OF NEW MOISTURE. PLENTY OF EXISTING MOISTURE TO
WORK WITH FROM CENTRAL PIMA COUNTY EASTWARD SO WILL KEEP THE
STANDARD MONSOON FORECAST GOING FOR ALL AREAS EXCEPT THE FAR WEST.
TUS 4333. OKULSKI

.TWC...NONE

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 23, 5:32 PM MSTFlash Flood WarningTWCGraham63 min
Jul 23, 9:05 PM MSTSevere Thunderstorm WarningTWCPima45 min
Jul 24, 1:23 PM MSTSevere Thunderstorm WarningTWCCochise47 min
Jul 24, 1:59 PM MSTSevere Thunderstorm WarningTWCCochise46 min

Nearby

Flash Flood Warnings in Arizona, 1998Every flash flood warning in 1998

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.