Alert archive / California / Flash Flood Warnings in 2017
Flash Flood Warning 55, NWS San Francisco Bay Area, CA
NWS San Francisco Bay Area, CA issued this flash flood warning at Feb 20, 2017, 7:40 AM PST for Santa Cruz County, California. It was in force for 6 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, 7:40 AM PST (15:40 UTC)
- Expired
- Feb 20, 2017, 1:30 PM PST
- In force
- 6 hr
- Issued by
- NWS San Francisco Bay Area, CA
- Area
- Storm-based polygon
- Flood severity
- None
County Santa Cruz County, CA
The radar
The San Francisco radar (KMUX), 18 km from the middle of the area, began a volume at 15:40 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, 3.7 hours before the alert went out and 74 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
- 515 m above ground
- 0-6 km bulk shear
- 75 kt
- 0-1 km storm-relative helicity
- 364 m²/s²
- 0-3 km storm-relative helicity
- 367 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
146 WGUS56 KMTR 201540 FFWMTR CAC087-202130- /O.NEW.KMTR.FF.W.0055.170220T1540Z-170220T2130Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ BULLETIN - EAS ACTIVATION REQUESTED Flash Flood Warning National Weather Service San Francisco CA 740 AM PST MON FEB 20 2017 The National Weather Service in The San Francisco Bay Area has issued a * Flash Flood Warning for... Central Santa Cruz County in northern California... * Until 130 PM PST * At 730 AM PST, the Big Trees stream gage on the San Lorenzo River in Felton indicated rapid rise in water levels which are approaching flood stage. Water levels are forecast to rise above flood stage later today as continued heavy rain is expected throughout the remainder of the day in the Santa Cruz Mountains. * Some locations that will experience flooding include... Felton Grove, Paradise Park, Tannery Arts Center and the San Lorenzo benchlands by the County building, Love Creek, Ben Lomond and lower Zayante Creek. PRECAUTIONARY/PREPAREDNESS ACTIONS... Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles. 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 3715 12209 3697 12200 3696 12203 3714 12215 $$ MWS
1 follow-up statement
139 WGUS76 KMTR 202123 FFSMTR Flash Flood Statement National Weather Service San Francisco CA 123 PM PST MON FEB 20 2017 CAC087-202131- /O.EXP.KMTR.FF.W.0055.000000T0000Z-170220T2130Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Santa Cruz CA- 123 PM PST MON FEB 20 2017 ...THE FLASH FLOOD WARNING FOR CENTRAL SANTA CRUZ COUNTY WILL EXPIRE AT 130 PM PST... Water levels have receded on the San Lorenzo River, but are expected to rise again later today in response to additional rainfall. At that time we will issue another Flash Flood Warning to reflect the continued threat. Please continue to heed any remaining road closures, evacuations, or safety considerations. LAT...LON 3715 12209 3697 12200 3696 12203 3714 12215 $$ MWS
The office that day
Everything else NWS San Francisco Bay Area, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 20, 3:53 AM PST | River Flood Warning | MTR | Santa Clara | 59 hr |
| Feb 20, 4:23 AM PST | Flash Flood Warning | MTR | Monterey | 3 hr |
| Feb 20, 5:03 AM PST | River Flood Warning | MTR | Monterey | 29 hr |
| Feb 20, 7:07 AM PST | Flash Flood Warning | MTR | Monterey | 6 hr |
| Feb 20, 7:35 AM PST | Areal Flood Advisory | MTR | Marin, Napa, City and County of San Francisco, San Mateo, Sonoma | 3 hr |
| Feb 20, 7:44 AM PST | Areal Flood Advisory | MTR | San Mateo, Santa Clara, Santa Cruz | 3 hr |
| Feb 20, 8:14 AM PST | Flash Flood Warning | MTR | Marin, Sonoma | 4 hr |
| Feb 20, 8:22 AM PST | Areal Flood Warning | MTR | Sonoma | 60 hr |
| Feb 20, 8:56 AM PST | Flash Flood Warning | MTR | San Benito | 6 hr |
| Feb 20, 9:04 AM PST | Flash Flood Warning | MTR | Santa Cruz | 6 hr |
| Feb 20, 10:13 AM PST | Flash Flood Warning | MTR | San Benito, Santa Clara | 6 hr |
| Feb 20, 10:26 AM PST | Flash Flood Warning | MTR | Alameda | 6 hr |
| Feb 20, 10:34 AM PST | Areal Flood Advisory | MTR | Marin, Napa, City and County of San Francisco, San Mateo, Sonoma | 3 hr |
| Feb 20, 10:48 AM PST | Areal Flood Advisory | MTR | San Mateo, Santa Clara, Santa Cruz | 3 hr |
| Feb 20, 11:21 AM PST | Areal Flood Advisory | MTR | Alameda, Contra Costa, Santa Clara | 3 hr |
| Feb 20, 1:32 PM PST | Areal Flood Advisory | MTR | Marin, Napa, City and County of San Francisco, San Mateo, Sonoma | 3 hr |
| Feb 20, 1:48 PM PST | Areal Flood Advisory | MTR | San Mateo, Santa Clara, Santa Cruz | 3 hr |
| Feb 20, 2:14 PM PST | Areal Flood Advisory | MTR | Monterey | 4 hr |
| Feb 20, 2:24 PM PST | Small Craft Advisory | MTR | 18 hr | |
| Feb 20, 2:40 PM PST | Areal Flood Advisory | MTR | San Mateo | 65 min |
| Feb 20, 3:23 PM PST | Areal Flood Warning | MTR | Santa Clara | 6 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.