Alert archive / California / Flash Flood Warnings in 2012
Flash Flood Warning 2, NWS San Francisco Bay Area, CA
NWS San Francisco Bay Area, CA issued this flash flood warning at Nov 30, 2012, 6:22 AM PST for Sonoma 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
- Nov 30, 2012, 6:22 AM PST (14:22 UTC)
- Expired
- Nov 30, 2012, 9:15 AM PST
- In force
- 3 hr
- Issued by
- NWS San Francisco Bay Area, CA
- Area
- Storm-based polygon
- Flood severity
- None
County Sonoma County, CA
The radar
The Sacramento radar (KDAX), 86 km from the middle of the area, began a volume at 14:25 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 12:00Z, 2.4 hours before the alert went out and 70 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
- 60 J/kg
- Mixed-layer CIN
- -60 J/kg
- Mixed-layer LCL
- 551 m above ground
- 0-6 km bulk shear
- 67 kt
- 0-1 km storm-relative helicity
- 462 m²/s²
- 0-3 km storm-relative helicity
- 616 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.5
The text
As transmitted, in the capitals the NWS used until 2016.
930 WGUS56 KMTR 301422 FFWMTR CAC097-301715- /O.NEW.KMTR.FF.W.0002.121130T1422Z-121130T1715Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ BULLETIN - EAS ACTIVATION REQUESTED FLASH FLOOD WARNING NATIONAL WEATHER SERVICE SAN FRANCISCO CA 622 AM PST FRI NOV 30 2012 THE NATIONAL WEATHER SERVICE IN THE SAN FRANCISCO BAY AREA HAS ISSUED A * FLASH FLOOD WARNING FOR... SONOMA COUNTY IN WESTERN CALIFORNIA... THIS INCLUDES THE CITY OF PETALUMA... * UNTIL 915 AM PST. * AT 614 AM PST...NWS DOPPLER RADAR AND AUTOMATED RAIN GAGES INDICATED THAT FLASH FLOODING IS OCCURRING IN SONOMA COUNTY ON PENNGROVE STREAM NEAR PETALUMA. THE PENNGROVE CREEK HAS FLOODED ACCORDING TO AUTOMATED MONITORING GAUGES AND WILL CONTINUE TO RISE DOWNSTREAM THROUGH PETALUMA. FLASH FLOODING ALONG THIS CREEK IS EXPECTED TO CONTINUE AS RAIN WILL FALL THROUGH THE MORNING. HOURLY RATES WILL INCREASE AGAIN AS A SECOND AREA OF HEAVY RAIN MOVES INTO THE AREA. * LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO TEMELEC. 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. IT IS IMPORTANT FOR CAMPERS AND HIKERS TO KNOW WHERE THEY ARE RELATIVE TO CREEKS...STREAMS...OR RIVERS WHICH CAN BECOME DANGEROUS IN HEAVY RAINS. BE PARTICULARLY AWARE IN HILLY TERRAIN WHERE MANY LOW WATER CROSSINGS CAN QUICKLY BECOME KILLERS. 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 3832 12269 3830 12250 3818 12249 3821 12270 $$ JOHNSON
1 follow-up statement
140 WGUS76 KMTR 301441 FFSMTR FLASH FLOOD STATEMENT NATIONAL WEATHER SERVICE SAN FRANCISCO CA 641 AM PST FRI NOV 30 2012 CAC097-301715- /O.CON.KMTR.FF.W.0002.000000T0000Z-121130T1715Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ SONOMA CA- 641 AM PST FRI NOV 30 2012 ...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 915 AM PST FOR SONOMA COUNTY... AT 637 AM PST...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO INDICATE A RAIN RODUCING FLASH FLOODING OVER THE WARNED AREA. FLOODING IS CURRENTLY OBSERVED IN WILLOW BROOK CREEK NEAR PETALUMA AT PENNGROVE PARK. RISES ON THE WILLOW BROOK CREEK WILL CONTINUE THIS MORNING AT THE OLD REDWOOD HIGHWAY BRIDGE AND DOWNSTREAM ON THE WILLOW BROOK CREEK. LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO TEMELEC. PRECAUTIONARY/PREPAREDNESS ACTIONS... MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN. && LAT...LON 3832 12269 3830 12250 3818 12249 3821 12270 $$ JOHNSON
The office that day
Everything else NWS San Francisco Bay Area, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Nov 30, 4:16 AM PST | Flash Flood Warning | MTR | Sonoma | 119 min |
| Nov 30, 5:38 AM PST | Areal Flood Advisory | MTR | Santa Cruz | 6 hr |
| Nov 30, 8:27 AM PST | Areal Flood Advisory | MTR | Alameda, Contra Costa, Marin, Monterey, San Benito, City and County of San Francisco and 3 more | 3 hr |
| Nov 30, 9:02 AM PST | Areal Flood Advisory | MTR | Marin, Napa, Sonoma | 118 min |
| Nov 30, 9:29 AM PST | Flash Flood Warning | MTR | Monterey | 61 min |
| Nov 30, 10:38 AM PST | Flash Flood Warning | MTR | Monterey | 82 min |
| Nov 30, 11:03 AM PST | River Flood Watch | MTR | Sonoma | 26 days |
| Nov 30, 11:25 AM PST | Areal Flood Advisory | MTR | Alameda, Contra Costa, Marin, Monterey, San Benito, City and County of San Francisco and 3 more | 3 hr |
| Nov 30, 11:59 AM PST | Flash Flood Warning | MTR | Monterey | 3 hr |
| Nov 30, 2:56 PM PST | Small Craft Advisory | MTR | 47 hr |
Nearby
Flash Flood Warnings in California, 2012Every flash flood warning in 2012
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.