Alert archive / California / Flash Flood Warnings in 1999

Flash Flood Warning 1, NWS Eureka, CA

August 6, 1999Trinity County, California

NWS Eureka, CA issued this flash flood warning at Aug 6, 1999, 1:41 PM PDT for Trinity County, California. It was in force for 3 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
Aug 6, 1999, 1:41 PM PDT (20:41 UTC)
Expired
Aug 6, 1999, 4:35 PM PDT
In force
3 hr
Issued by
NWS Eureka, CA
Area
Whole counties

County Trinity County, CA

The radar

The Eureka (Bunker Hill) radar (KBHX), 101 km from the middle of the area, began a volume at 20:45 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

Medford/Jackson, OR (KMFR), launched 12:00Z, 8.7 hours before the alert went out and 193 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, Medford/Jackson, OR at 12:00Z on 1999-08-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 17 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Medford/Jackson, OR at 12:00Z on 1999-08-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 17 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
17 J/kg
Mixed-layer CIN
-284 J/kg
Mixed-layer LCL
686 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
17 m²/s²
0-3 km storm-relative helicity
22 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 KEKA 062041
FFWEKA
CAC105-062335-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE EUREKA CA
141 PM PDT FRI AUG 6 1999

THE NATIONAL WEATHER SERVICE IN EUREKA HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHEASTERN TRINITY COUNTY IN NORTHWESTERN CALIFORNIA

* UNTIL 435 PM PDT

* AT 134 PM PDT... NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  A THUNDERSTORM WITH VERY HEAVY RAIN 25 MILES SOUTH OF HAYFORK OR
  OVER SOUTH KELSEY PEAK ... MOVING SLOWLY TOWARD THE NORTHWEST.

* VERY HEAVY RAINFALL OF OVER 2 INCHES IN THE PAST HOUR OVER THE
  HEADWATERS OF THE MAD RIVER HAS RESULTED IN A VERY DANGEROUS FLASH
  FLOODING SITUATION FOR THE TRIBUTARIES OF THE MAD RIVER. HEAVY
  RAINFALL FROM THIS THUNDERSTORM WILL CONTINUE OVER THE
  HEADWATERS OF THE MAD RIVER THROUGH 330 PM.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT. IT IS
IMPORTANT TO KNOW WHERE YOU ARE RELATIVE TO RIVERS AND CREEKS...
WHICH CAN BECOME KILLERS IN HEAVY RAINS.

MRD

The office that day

Everything else NWS Eureka, CA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 6, 12:58 PM PDTSevere Thunderstorm WarningEKATrinity42 min
Aug 6, 12:58 PM PDTSevere Thunderstorm WarningEKATrinity87 min

Nearby

Flash Flood Warnings in California, 1999Every flash flood warning in 1999

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.