Alert archive / California / Flash Flood Warnings in 2017
Flash Flood Warning 71, NWS San Francisco Bay Area, CA
NWS San Francisco Bay Area, CA issued this flash flood warning at Feb 20, 2017, 10:15 PM PST for San Mateo 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
- Feb 20, 2017, 10:15 PM PST (06:15 UTC)
- Expired
- Feb 21, 2017, 1:15 AM PST
- In force
- 3 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), 37 km from the middle of the area, began a volume at 06:18 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, 6.3 hours before the alert went out and 53 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 521 m above ground
- 0-6 km bulk shear
- 99 kt
- 0-1 km storm-relative helicity
- 111 m²/s²
- 0-3 km storm-relative helicity
- 565 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
634
WGUS56 KMTR 210615
FFWMTR
CAC081-210915-
/O.NEW.KMTR.FF.W.0071.170221T0615Z-170221T0915Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service San Francisco CA
1015 PM PST MON FEB 20 2017
The National Weather Service in The San Francisco Bay Area has issued
a
* Flash Flood Warning for...
Southeastern San Mateo County in northern California...
* Until 115 AM PST
* At 1012 PM PST, the stream gauge report on Pescadero Creek at
Pescadero indicated Flash flooding is already occurring. A peak
stage level of 15.78 feet occurred at 9:45 pm. Levels are now
starting to decline but will remain above flood stage for the next
several hours.
* Flash flooding will remain over mainly rural areas of southeastern
San Mateo County.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, country roads, farmland, and other low lying
spots.
A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.
&&
LAT...LON 3726 12219 3722 12221 3726 12228 3724 12234
3724 12241 3728 12241 3727 12236 3729 12230
$$
Blier1 follow-up statement
023
WGUS76 KMTR 210912
FFSMTR
Flash Flood Statement
National Weather Service San Francisco CA
112 AM PST TUE FEB 21 2017
CAC081-210919-
/O.EXP.KMTR.FF.W.0071.000000T0000Z-170221T0915Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Mateo CA-
112 AM PST TUE FEB 21 2017
...THE FLASH FLOOD WARNING FOR SOUTHEASTERN SAN MATEO COUNTY WILL
EXPIRE AT 115 AM PST...
Flood waters on the Pescadero Creek have peaked and will continue to
recede through the night, yet remain above flood stage for the next
several hours. Thus, an Areal Flood Warning has been issued for the
warned area through 7 AM PST Tuesday. Please continue to heed any
remaining road closures.
LAT...LON 3726 12219 3722 12221 3726 12228 3724 12234
3724 12241 3728 12241 3727 12236 3729 12230
$$
RGassThe office that day
Everything else NWS San Francisco Bay Area, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 20, 4:13 PM PST | Flash Flood Warning | MTR | San Benito, Santa Clara | 6 hr |
| Feb 20, 4:34 PM PST | Flash Flood Warning | MTR | Alameda | 116 min |
| Feb 20, 5:02 PM PST | River Flood Warning | MTR | Monterey | 24 hr |
| Feb 20, 5:03 PM PST | Flash Flood Warning | MTR | Santa Clara | 87 min |
| Feb 20, 5:29 PM PST | Flash Flood Warning | MTR | San Mateo | 2 hr |
| Feb 20, 6:02 PM PST | Flash Flood Warning | MTR | Santa Cruz | 4 hr |
| Feb 20, 6:03 PM PST | Areal Flood Advisory | MTR | San Mateo | 4 hr |
| Feb 20, 6:18 PM PST | Areal Flood Advisory | MTR | Monterey | 12 hr |
| Feb 20, 6:36 PM PST | Flash Flood Warning | MTR | Alameda | 4 hr |
| Feb 20, 6:54 PM PST | Flash Flood Warning | MTR | Alameda | 3 hr |
| Feb 20, 7:17 PM PST | Flash Flood Warning | MTR | San Mateo | 3 hr |
| Feb 20, 9:15 PM PST | Areal Flood Warning | MTR | Santa Clara | 8 hr |
| Feb 20, 10:00 PM PST | Flash Flood Warning | MTR | Santa Cruz | 4 hr |
| Feb 20, 10:01 PM PST | Flash Flood Warning | MTR | Alameda | 3 hr |
| Feb 20, 10:16 PM PST | Areal Flood Warning | MTR | San Benito, Santa Clara | 12 hr |
| Feb 20, 10:34 PM PST | Areal Flood Advisory | MTR | Alameda | 12 hr |
| Feb 20, 10:42 PM PST | Areal Flood Warning | MTR | Alameda | 12 hr |
| Feb 20, 11:38 PM PST | Areal Flood Warning | MTR | Santa Clara | 12 hr |
| Feb 21, 12:14 AM PST | Areal Flood Warning | MTR | Monterey | 12 hr |
| Feb 21, 1:09 AM PST | Areal Flood Warning | MTR | San Mateo | 6 hr |
| Feb 21, 5:38 AM PST | Areal Flood Warning | MTR | San Benito, Santa Clara | 15 hr |
| Feb 21, 8:41 AM PST | Small Craft Advisory for Hazardous Seas | MTR | 12 hr | |
| Feb 21, 11:29 AM PST | Areal Flood Warning | MTR | Santa Clara | 36 hr |
Nearby
Flash Flood Warnings in California, 2017Every flash flood warning in 2017
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.