Alert archive / Arizona / Flash Flood Warnings in 1998

Flash Flood Warning 22, NWS Tucson, AZ

July 19, 1998Pima County, Arizona

NWS Tucson, AZ issued this flash flood warning at Jul 19, 1998, 6:52 PM MST for Pima County, Arizona. It was in force for 68 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 19, 1998, 6:52 PM MST (01:52 UTC)
Expired
Jul 19, 1998, 8:00 PM MST
In force
68 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 01:53 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, 1.9 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 1998-07-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 262 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 1998-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -21 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
262 J/kg
Mixed-layer CIN
-79 J/kg
Mixed-layer LCL
2738 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
-21 m²/s²
0-3 km storm-relative helicity
-23 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 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 19, 2:30 PM MST, 4 hours 22 minutes earlier.

Area forecast discussion, Jul 19, 2:30 PM MST, 4 hours 22 minutes before
SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
230 PM MST SUN JUL 19 1998

SYNOPSIS...SURGE OF MOISTURE FROM THE GULF OF CALIFORNIA COMBINED
WITH AN UPPER LEVEL IMPULSE WILL LEAD TO INCREASED THUNDERSTORM
ACTIVITY ACROSS SOUTHEAST ARIZONA.

DISCUSSION...HIGH REMAINS CENTERED NEAR THE UT/AZ BORDER...SHIFTING
SLOWLY EASTWARD OVER THE NEXT 48 HRS. UPPER LEVEL IMPULSE SPINNING
UNDER IT IN EASTERLY INTO SOUTHEAST AZ WILL CONTINUE TO SHIFT SLOWLY
WESTWARD. STRONG SURGE SIGNAL EVIDENT IN YUMA OVERNIGHT SPREADING
INTO THE LOWER DESERTS CIRCULATING INTO THE WESTERN 2/3RDS OF OUR
AREA. LOTS OF SUNSHINE...VERY UNSTABLE OUTSIDE OF SUBSIDENCE
IMMEDIATELY AHEAD OF IMPULSE. EVERYTHING POINTS TOWARDS A
SIGNIFICANT THUNDERSTORM AFTERNOON AND EVENING WITH CONSIDERATION
FOR SEVERE AS WELL AS LOCALLY HEAVY RAINFALL. UPPER LEVEL DYNAMICS
MAY ASSIST STORM DEVELOPMENT / REDEVELOPMENT OVERNIGHT.

IF OVERNIGHT ACTIVITY TURNS OUT TO BE AS HEAVY AS PREDICTED...DEBRIS
CLOUD AND SOME STABILITY IN THE LOWER ATMOSPHERE COULD HELP DEPRESS
WIDESPREAD ACTIVITY TOMORROW. WILL TAYLOR THE FORECAST IN THAT
DIRECTION...BUT NOT COMPLETELY. OTHERWISE OVERALL GOOD THUNDERSTORM
CONDITIONS WILzL PERSIST INTO THE EXTENDED. TUS 6333. MEYER

.TWC...NONE.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 19, 6:45 PM MSTFlash Flood WarningTWCPima2 hr
Jul 19, 6:52 PM MSTSevere Thunderstorm WarningTWCPima68 min
Jul 19, 7:58 PM MSTSevere Thunderstorm WarningTWCPima32 min
Jul 20, 12:36 PM MSTSevere Thunderstorm WarningTWCPima64 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.