Alert archive / California / Flash Flood Warnings in 2008

Flash Flood Warning 4, NWS San Francisco Bay Area, CA

January 25, 2008Marin County, California

NWS San Francisco Bay Area, CA issued this flash flood warning at Jan 25, 2008, 10:43 PM PST for Marin 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 outline as issued.

The facts

Issued
Jan 25, 2008, 10:43 PM PST (06:43 UTC)
Expired
Jan 26, 2008, 1:45 AM PST
In force
3 hr
Issued by
NWS San Francisco Bay Area, CA
Area
Storm-based polygon
Flood severity
None

County Marin County, CA

The radar

The Sacramento radar (KDAX), 99 km from the middle of the area, began a volume at 06:45 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

Oakland, CA (KOAK), launched 00:00Z, 6.7 hours before the alert went out and 42 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, Oakland, CA at 00:00Z on 2008-01-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Oakland, CA at 00:00Z on 2008-01-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 217 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
622 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
217 m²/s²
0-3 km storm-relative helicity
426 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 
WGUS56 KMTR 260648
FFWMTR
CAC041-260945-
/O.NEW.KMTR.FF.W.0004.080126T0643Z-080126T0945Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
1043 PM PST FRI JAN 25 2008

THE NATIONAL WEATHER SERVICE IN SAN FRANCISCO BAY AREA HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHEASTERN MARIN COUNTY IN WESTERN CALIFORNIA...
  THIS INCLUDES THE CITY OF SAN RAFAEL...

* UNTIL 145 AM PST

* AT 1036 PM PST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED  
  AN AREA OF MODERATE TO LOCALLY HEAVY RAIN ACROSS MARIN COUNTY.     
  RADAR ALSO INDICATED THAT MODERATE TO LOCALLY HEAVY RAIN WILL      
  CONTINUE OVER THE NEXT ONE TO TWO HOURS. THE CORTE MADERA          
  CREEK AT ROSS HAS REACHED BANKFUL AND IS CURRENTLY HOLDING         
  STEADY. ANY ADDITIONAL HEAVY RAINFALL MAY CAUSE THE CORTE MADERA   
  CREEK TO FLOOD COMMUNITIES ALONG ITS BANKS.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO SAN        
  ANSELMO...FAIRFAX...KENTFIELD AND ROSS.

RUNOFF FROM HEAVY RAINFALL WILL CAUSE LOCALIZED FLOODING OF SMALL
CREEKS AS WELL AS ROADWAYS...UNDERPASSES AND OTHER LOW LYING SPOTS.
DO NOT ATTEMPT TO CROSS SWIFTLY FLOWING WATER OR WATER OF UNKNOWN
DEPTH. TURN AROUND...DONT DROWN.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT CAN BE DIFFICULT TO RECOGNIZE
FLOODING. DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. TURN AROUND...DONT DROWN.

A FLASH FLOOD WARNING MEANS THAT FLOODING HAS BEEN REPORTED OR IS
IMMINENT. IF YOU ARE IN THE WARNING AREA TAKE NECESSARY PRECAUTIONS
IMMEDIATELY. MOVE TO HIGHER GROUND.

TO REPORT FLOODING...HAVE THE NEAREST LAW ENFORCEMENT AGENCY RELAY
YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE.

LAT...LON 3802 12264 3807 12249 3782 12246 3788 12265
TIME...MOT...LOC 0643Z 180DEG 0KT 3791 12253

$$

MEHLE/DYKEMA

The office that day

Everything else NWS San Francisco Bay Area, CA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jan 25, 7:46 PM PSTFlash Flood WarningMTRMarin3 hr

Nearby

Flash Flood Warnings in California, 2008Every flash flood warning in 2008

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.