Alert archive / California / Flash Flood Warnings in 1998

Flash Flood Warning 7, NWS Phoenix, AZ

July 23, 1998Riverside County, California

NWS Phoenix, AZ issued this flash flood warning at Jul 23, 1998, 2:09 PM PDT for Riverside County, California. It was in force for 2 hr. 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, 2:09 PM PDT (21:09 UTC)
Expired
Jul 23, 1998, 4:10 PM PDT
In force
2 hr
Issued by
NWS Phoenix, AZ
Area
Whole counties

County Riverside County, CA

The nearest sounding before it

Yuma Intl Airpor, AZ (KYUM), launched 12:00Z, 9.2 hours before the alert went out and 178 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, Yuma Intl Airpor, AZ at 12:00Z on 1998-07-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 134 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Yuma Intl Airpor, AZ at 12:00Z on 1998-07-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 9 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
134 J/kg
Mixed-layer CIN
-194 J/kg
Mixed-layer LCL
1601 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
9 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

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

000 
TTAA00 KPHX 232110
FFWPHX
CAC065-232310-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
209 PM MST (209 PM PDT) THU JUL 23 1998

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

*  FLASH FLOOD WARNING FOR
   WEST CENTRAL RIVERSIDE COUNTY IN SOUTHEASTERN CALIFORNIA

*  UNTIL 410 PM PDT (410 PM MST)

*  AT 205 PM PDT YUMA DOPPLER RADAR ESTIMATED RAINFALL RATES OF UP
   TO 2 INCHES PER HOUR. AS A RESULT...FLASH FLOODING IS THOUGHT
   TO BE IMMINENT IN THE WARNED LOCATIONS.

*  SOME LOCATIONS AFFECTED INCLUDE...
   JOSHUA TREE NATIONAL PARK AROUND VICTORY PALMS AND SUMMIT SPRING

HIKING TRAILS IN THE SOUTHEAST CORNER OF JOSHUA TREE NATIONAL PARK
ARE THOUGHT TO BE THREATENED...PARTCULARLY THOSE SOUTH AND SOUTHEAST
OF SUMMIT SPRING.

WILT

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 22, 8:05 PM PDTFlash Flood WarningPSRRiverside2 hr

Nearby

Flash Flood Warnings in California, 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.