Alert archive / California / Flash Flood Warnings in 2011
Flash Flood Warning 4, NWS San Francisco Bay Area, CA
NWS San Francisco Bay Area, CA issued this flash flood warning at Mar 24, 2011, 5:03 PM PDT for San Mateo 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 outline as issued.
The facts
- Issued
- Mar 24, 2011, 5:03 PM PDT (00:03 UTC)
- Expired
- Mar 24, 2011, 7:30 PM PDT
- In force
- 2 hr
- Issued by
- NWS San Francisco Bay Area, CA
- Area
- Storm-based polygon
- Flood severity
- None
County San Mateo County, CA
The radar
The San Francisco radar (KMUX), 44 km from the middle of the area, began a volume at 00:06 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, 0.1 hours before the alert went out and 56 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.
- Mixed-layer CAPE
- 2 J/kg
- Mixed-layer CIN
- -2 J/kg
- Mixed-layer LCL
- 686 m above ground
- 0-6 km bulk shear
- 72 kt
- 0-1 km storm-relative helicity
- -13 m²/s²
- 0-3 km storm-relative helicity
- -14 m²/s²
- Significant tornado parameter
- -0.0
- Supercell composite
- -0.0
The text
As transmitted, in the capitals the NWS used until 2016.
085
WGUS56 KMTR 250003
FFWMTR
CAC081-250130-
/O.NEW.KMTR.FF.W.0004.110325T0003Z-110325T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
503 PM PDT THU MAR 24 2011
THE NATIONAL WEATHER SERVICE IN THE SAN FRANCISCO BAY AREA HAS
ISSUED A
* FLASH FLOOD WARNING FOR...
THE PESCADERO CREEK IN SAN MATEO COUNTY IN WESTERN CALIFORNIA...
* UNTIL 630 PM PDT.
* AT 459 PM PDT...NWS DOPPLER RADAR AND AUTOMATED RAIN GAGES
INDICATED A BAND OF HEAVY SHOWERS THAT DEVELOPED AND IS MOVING OVER
THE PESCADERO CREEK BASIN. THE CURRENT STAGE IS JUST UNDER THE
FLOOD STAGE OF 12 FEET. THE RIVER IS EXPECTED TO GO OVER FLOOD
STAGE IN THE NEXT HOUR BEFORE BEGINNING TO RECEDE AS THE SHOWER
ACTIVITY WINDS DOWN.
* THE STORM IS MAINLY OVER MAINLY RURAL AREAS OF THE INDICATED
COUNTY.
A FLASH FLOOD WARNING MEANS THAT FLOODING IS OCCURRING OR IS
IMMINENT.
RUNOFF FROM HEAVY RAINFALL WILL CAUSE LOCALIZED FLOODING OF SMALL
CREEKS AND STREAMS 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.
TO REPORT FLOODING...HAVE THE NEAREST LAW ENFORCEMENT AGENCY RELAY
YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE.
LAT...LON 3729 12242 3726 12228 3720 12230 3721 12242
3723 12243
$$
WJK2 follow-up statements
925
WGUS56 KMTR 250127
FFWMTR
CAC081-250230-
/O.EXT.KMTR.FF.W.0004.000000T0000Z-110325T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
627 PM PDT THU MAR 24 2011
THE NATIONAL WEATHER SERVICE IN THE SAN FRANCISCO BAY AREA HAS
EXTENDED THE
* FLASH FLOOD WARNING FOR...
THE PESCADERO CREEK IN SAN MATEO COUNTY IN WESTERN CALIFORNIA...
* UNTIL 730 PM PDT.
* AT 620 PM PDT...NWS DOPPLER RADAR AND AUTOMATED RAIN GAGES
INDICATED CONTINUED MODERATE RAINFALL OVER THE PESCADERO CREEK
BASIN. THE CURRENT STAGE HAS BEEN HOVERING RIGHT AROUND THE FLOOD
STAGE OF 12 FEET. WITH ADDITIONAL SHOWERS STILL EXPECTED MAINLY
FOR ABOUT ANOTHER HOUR...THIS FLASH FLOOD WARNING IS EXTENDED.
* THE STORM PRODUCING WILL OTHERWISE REMAIN OVER MAINLY RURAL AREAS
OF THE INDICATED COUNTY.
A FLASH FLOOD WARNING MEANS THAT FLOODING IS OCCURRING OR IS
IMMINENT.
BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLASH FLOODING IS OBSERVED ACT QUICKLY. MOVE
UP TO HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS
SUBJECT TO FLOODING WHEN WATER BEGINS RISING.
TO REPORT FLOODING...HAVE THE NEAREST LAW ENFORCEMENT AGENCY RELAY
YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE.
LAT...LON 3729 12242 3726 12228 3720 12230 3721 12242
3723 12243
$$
WJK737
WGUS76 KMTR 250230
FFSMTR
FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
730 PM PDT THU MAR 24 2011
CAC081-250235-
/O.EXP.KMTR.FF.W.0004.000000T0000Z-110325T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SAN MATEO CA-
730 PM PDT THU MAR 24 2011
...THE FLASH FLOOD WARNING WILL EXPIRE AT 730 PM PDT FOR THE
PESCADERO CREEK SAN MATEO COUNTY...
AT 7:20 PM PDT THE LEVEL OF THE PESCADERO CREEK WAS AT 11.75 FEET...
WHICH IS JUST BELOW FLOOD STAGE OF 12 FEET. THE CREEK LEVEL IS
TRENDING DOWN AND IS EXPECTED TO CONTINUE TO FALL THROUGH THE
EVENING. THEREFORE...THE FLASH FLOOD WARNING WILL BE ALLOWED TO
EXPIRE AT 7:30 PM. SCATTERED SHOWERS ARE FORECAST FOR THE REMAINDER
OF THE EVENING. SOME SHOWERS MAY PRODUCE BRIEF HEAVY RAIN.
HOWEVER...FURTHER RISES ARE NOT EXPECTED ON THE PESCADERO CREEK.
LAT...LON 3729 12242 3726 12228 3720 12230 3721 12242
3723 12243
$$
DYKEMAThe office that day
Everything else NWS San Francisco Bay Area, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 24, 5:27 PM PDT | Flash Flood Warning | MTR | Monterey | 3 hr |
| Mar 24, 9:58 PM PDT | Small Craft Advisory for Hazardous Seas | MTR | 26 hr | |
| Mar 25, 3:09 PM PDT | Small Craft Advisory | MTR | 24 hr | |
| Mar 25, 3:09 PM PDT | High Surf Advisory | MTR | Marin, Monterey, City and County of San Francisco, San Mateo, Santa Cruz, Sonoma | 8 hr |
Nearby
Flash Flood Warnings in California, 2011Every flash flood warning in 2011
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.