Alert archive / California / Flash Flood Warnings in 2017
Flash Flood Warning 20, NWS San Francisco Bay Area, CA
NWS San Francisco Bay Area, CA issued this flash flood warning at Jan 10, 2017, 8:01 PM PST for Alameda County, California. It was in force for 10 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 10, 2017, 8:01 PM PST (04:01 UTC)
- Expired
- Jan 11, 2017, 6:00 AM PST
- In force
- 10 hr
- Issued by
- NWS San Francisco Bay Area, CA
- Area
- Storm-based polygon
- Flood severity
- None
County Alameda County, CA
The radar
The San Francisco radar (KMUX), 49 km from the middle of the area, began a volume at 04:03 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, 4.0 hours before the alert went out and 28 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
- 40 J/kg
- Mixed-layer CIN
- -8 J/kg
- Mixed-layer LCL
- 585 m above ground
- 0-6 km bulk shear
- 74 kt
- 0-1 km storm-relative helicity
- 245 m²/s²
- 0-3 km storm-relative helicity
- 158 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted.
783 WGUS56 KMTR 110401 FFWMTR CAC001-110800- /O.NEW.KMTR.FF.W.0020.170111T0401Z-170111T0800Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ BULLETIN - EAS ACTIVATION REQUESTED Flash Flood Warning National Weather Service San Francisco CA 801 PM PST TUE JAN 10 2017 The National Weather Service in The San Francisco Bay Area has issued a * Flash Flood Warning for... South central Alameda County in northern California... * Until midnight PST * At 800 PM PST, Doppler radar indicated heavy rain moving through Alameda County. Based on radar data, periods of heavy rain will continue for the next hour. Heavy rain on already saturated soil will result in rapid runoff and flooding. A stream gauge on the Alameda Creek near Niles indicated the creek had risen slightly above flood stage at 8 pm and was continuing to rise rapidly. Flash flooding is expected to begin shortly. * Some locations that will experience flooding include... Locations along the Alameda Creek in Niles Canyon. PRECAUTIONARY/PREPAREDNESS ACTIONS... Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles. && LAT...LON 3762 12188 3757 12187 3755 12201 3760 12202 $$
2 follow-up statements
183 WGUS56 KMTR 110744 FFWMTR CAC001-111400- /O.EXT.KMTR.FF.W.0020.000000T0000Z-170111T1400Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ BULLETIN - EAS ACTIVATION REQUESTED Flash Flood Warning National Weather Service San Francisco CA 1144 PM PST TUE JAN 10 2017 The National Weather Service in The San Francisco Bay Area has extended the * Flash Flood Warning for... South central Alameda County in northern California... * Until 600 AM PST Wednesday * At 1139 PM PST, Doppler radar indicated rain moving across the warned area. Flash flooding is already occurring. Continued rain on already saturated soil will result in rapid runoff and flooding. A stream gauge on the Alameda Creek near Niles indicated the creek has risen above flood stage at 11 pm and was continuing to rise rapidly. Flash flooding is occuring. * Some locations that will experience flooding include... locations along the Alameda Creek in Niles Canyon. PRECAUTIONARY/PREPAREDNESS ACTIONS... Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles. Be especially cautious at night when it is harder to recognize the dangers of flooding. A Flash Flood Warning means that flooding is imminent or occurring. If you are in the warned area move to higher ground immediately. Residents living along streams and creeks should take immediate precautions to protect life and property. && LAT...LON 3762 12188 3757 12187 3755 12201 3760 12202 $$
105 WGUS76 KMTR 111356 FFSMTR Flash Flood Statement National Weather Service San Francisco CA 556 AM PST WED JAN 11 2017 CAC001-111405- /O.EXP.KMTR.FF.W.0020.000000T0000Z-170111T1400Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Alameda CA- 556 AM PST WED JAN 11 2017 ...THE FLASH FLOOD WARNING FOR SOUTH CENTRAL ALAMEDA COUNTY WILL EXPIRE AT 600 AM PST... The heavy rain has ended although brief heavy showers will continue today. Flood waters are receding. Please continue to heed any remaining road closures. LAT...LON 3762 12188 3757 12187 3755 12201 3760 12202 $$ rww
The office that day
Everything else NWS San Francisco Bay Area, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jan 10, 4:26 PM PST | Areal Flood Warning | MTR | Sonoma | 24 hr |
| Jan 10, 5:46 PM PST | Areal Flood Advisory | MTR | City and County of San Francisco, San Mateo | 4 hr |
| Jan 10, 6:18 PM PST | Areal Flood Warning | MTR | Sonoma | 12 hr |
| Jan 10, 6:41 PM PST | Areal Flood Warning | MTR | Santa Clara | 15 hr |
| Jan 10, 7:26 PM PST | Flash Flood Warning | MTR | Santa Cruz | 3 hr |
| Jan 10, 7:59 PM PST | Areal Flood Warning | MTR | Napa | 12 hr |
| Jan 10, 8:28 PM PST | Areal Flood Warning | MTR | Marin | 12 hr |
| Jan 10, 8:43 PM PST | Special Weather Statement | MTR | Santa Cruz | 47 min |
| Jan 10, 8:45 PM PST | Special Marine Warning | MTR | 30 min | |
| Jan 10, 9:03 PM PST | Gale Warning | MTR | 5 hr | |
| Jan 10, 9:03 PM PST | Small Craft Advisory for Rough Bar | MTR | 36 hr | |
| Jan 10, 9:03 PM PST | Small Craft Advisory | MTR | 5 hr | |
| Jan 10, 9:14 PM PST | Flash Flood Warning | MTR | Monterey | 9 hr |
| Jan 10, 9:20 PM PST | Special Marine Warning | MTR | 40 min | |
| Jan 10, 10:07 PM PST | Areal Flood Advisory | MTR | Santa Clara | 5 hr |
| Jan 10, 10:53 PM PST | Flash Flood Warning | MTR | Santa Cruz | 6 hr |
| Jan 10, 11:07 PM PST | Areal Flood Advisory | MTR | City and County of San Francisco, San Mateo | 113 min |
| Jan 10, 11:43 PM PST | Special Marine Warning | MTR | 32 min | |
| Jan 10, 11:50 PM PST | Areal Flood Advisory | MTR | Alameda, Contra Costa | 115 min |
| Jan 11, 12:27 AM PST | Areal Flood Advisory | MTR | San Mateo | 4 hr |
| Jan 11, 12:45 AM PST | River Flood Warning | MTR | Monterey | 15 hr |
| Jan 11, 6:03 AM PST | Flash Flood Warning | MTR | Monterey | 3 hr |
| Jan 11, 7:43 AM PST | Areal Flood Warning | MTR | San Benito, Santa Clara | 12 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.