Alert archive / California / Areal Flood Warnings in 2017

Areal Flood Warning 2, NWS San Francisco Bay Area, CA

January 8, 2017Santa Clara County, California

NWS San Francisco Bay Area, CA issued this areal flood warning at Jan 8, 2017, 7:54 PM PST for Santa Clara 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 counties it named.

The facts

Issued: Jan 8, 2017, 7:54 PM PST (03:54 UTC)
Expired: Jan 8, 2017, 10:45 PM PST
In force: 3 hr
Issued by: NWS San Francisco Bay Area, CA
Area: Storm-based polygon
Flood severity: None

County Santa Clara County, CA

The radar

The San Francisco radar (KMUX), 20 km from the middle of the area, began a volume at 03:57 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, 3.9 hours before the alert went out and 71 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 678 m above ground
0-6 km bulk shear: 83 kt
0-1 km storm-relative helicity: 320 m²/s²
0-3 km storm-relative helicity: 361 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this areal flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS San Francisco Bay Area, CA wrote its last area forecast discussion before this areal flood warning went out at Jan 8, 5:20 PM PST, 2 hours 34 minutes earlier.

Area forecast discussion, Jan 8, 5:20 PM PST, 2 hours 34 minutes before

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In the hours before

Local storm report, Jan 8, 1:58 PM PST, 5 hours 56 minutes before

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      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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Local storm report, Jan 8, 6:38 PM PST, 1 hour 16 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
638 PM PST SUN JAN 08 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0730 AM     FLASH FLOOD      FREMONT                 37.53N 122.00W
01/07/2017                   ALAMEDA            CA   NEWSPAPER

            LOCALIZED FLOODING AND INTERMITTENT HEAVY RAINS ON
            HIGHWAY 880 AT MISSION BLVD EXIT CAUSED FATAL CRASH
            TAKING LIFE OF FEMALE DRIVER

0830 AM     FLASH FLOOD      5 SW OAKLAND            37.72N 122.29W
01/07/2017                   PZZ531             CA   NEWSPAPER

            TAXICAB DROVE INTO ESTUARY NEAR OAKLAND INTERNATIONAL
            AIRPORT DRIVER. DIVERS FOUND DRIVERS BODY IN AUTO.

0436 AM     FLASH FLOOD      6 S VALLEJO             38.03N 122.26W
01/08/2017                   CONTRA COSTA       CA   LAW ENFORCEMENT

            LARGE POOL OF WATER WB 80 AT WILLOW

0459 AM     NON-TSTM WND DMG 27 W CLOVERDALE         38.75N 123.51W
01/08/2017                   SONOMA             CA   LAW ENFORCEMENT

            TREE BLOCKING ROAD ON SR1

0459 AM     TSTM WND DMG     3 NNW SALINAS           36.72N 121.66W
01/08/2017                   MONTEREY           CA   LAW ENFORCEMENT

            EXTREMELY LARGE TREE ACROSS THE WHOLE LANE.

0722 AM     FLOOD            NAPA                    38.30N 122.30W
01/08/2017                   NAPA               CA   LAW ENFORCEMENT

            ROADWAY FLOODING REPORTED NEAR GOLDEN GATE DR

0722 AM     FLOOD            SONOMA                  38.29N 122.46W
01/08/2017                   SONOMA             CA   LAW ENFORCEMENT

            ROHNERT PARK EXPWY/STONY POINT IN ROHNERT PARK FLOODED.
            ROAD CLOSURES IN EFFECT.

0958 AM     FLOOD            HEALDSBURG              38.62N 122.86W
01/08/2017                   SONOMA             CA   LAW ENFORCEMENT

            WOHLER ROAD AT RIVER ROAD IS FLOODED.

1032 AM     NON-TSTM WND GST 3 W LOS GATOS           37.23N 122.01W
01/08/2017  M78.00 MPH       SANTA CLARA        CA   MESONET

1049 AM     FLOOD            HEALDSBURG              38.62N 122.86W
01/08/2017                   SONOMA             CA   LAW ENFORCEMENT

            WOHLER RD AT RIVER RD IS FLOODED.

1049 AM     FLOOD            ST. HELENA              38.50N 122.47W
01/08/2017                   NAPA               CA   LAW ENFORCEMENT

            DEER PARK RD BETWEEN HWY 29 AND SILVERADO TRAIL CLOSED
            DUE TO FLOODING. YOUNTVILLE CROSS RD ALSO IMPACTED.

1049 AM     FLOOD            ST. HELENA              38.50N 122.47W
01/08/2017                   NAPA               CA   LAW ENFORCEMENT

            DEER PARK RD BETWEEN HWY 29 AND SILVERADO TRAIL CLOSEDD
            DUE TO FLOODING. YOUNTVILLE CROSS RD ALSO IMPACTED.

0153 PM     HEAVY RAIN       1 WSW MORGAN HILL       37.13N 121.65W
01/08/2017  E0.00 INCH       SANTA CLARA        CA   TRAINED SPOTTER

            1.78 PRECIP INCHES MEASURED SINCE 8AM. WIDESPREAD MINOR
            FOODING IN MORGAN HILL.

0153 PM     NON-TSTM WND GST 10 W SAN RAFAEL         37.98N 122.69W
01/08/2017  M70.00 MPH       MARIN              CA   MESONET

&&

BBENJAMI

Local storm report, Jan 8, 7:02 PM PST, 52 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
702 PM PST SUN JAN 08 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0659 PM     FLOOD            5 W GILROY              37.01N 121.67W
01/08/2017                   SANTA CLARA        CA   DEPT OF HIGHWAYS

            HWY 152 CLOSED BOTH WAYS AT WATSONVILLE RD

&&

WPI

Local storm report, Jan 8, 7:11 PM PST, 43 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
711 PM PST SUN JAN 08 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0708 PM     DEBRIS FLOW      8 N SANTA CRUZ          37.09N 122.04W
01/08/2017                   SANTA CRUZ         CA   DEPT OF HIGHWAYS

            SOUTHBOUND HWY 17 AT GLENWOOD DR SLOW LANE BLOCKED BY MUD

&&

WPI

Local storm report, Jan 8, 7:34 PM PST, 20 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
734 PM PST SUN JAN 08 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0726 PM     DEBRIS FLOW      20 S BIG SUR RAWS       35.95N 121.79W
01/08/2017                   PZZ576             CA   BROADCAST MEDIA

            HIGHWAY 1 CLOSED NEAT FULLERS POINT DUE TO ROCKSLIDE

&&

WPI

The office that day

Everything else NWS San Francisco Bay Area, CA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jan 8, 4:34 PM PST	Flash Flood Warning	MTR	Santa Clara	3 hr
Jan 8, 8:21 PM PST	Special Marine Warning	MTR		24 min
Jan 8, 9:43 PM PST	Small Craft Advisory	MTR		5 hr
Jan 8, 9:43 PM PST	Small Craft Advisory	MTR		4 days
Jan 8, 10:45 PM PST	Areal Flood Warning	MTR	Santa Clara	6 hr
Jan 8, 11:09 PM PST	Flash Flood Warning	MTR	Monterey	3 hr
Jan 9, 2:44 AM PST	Gale Warning	MTR		42 hr
Jan 9, 2:55 AM PST	Coastal Flood Advisory	MTR	Alameda, Contra Costa, Marin, Monterey, Napa, City and County of San Francisco and 4 more	3 days
Jan 9, 3:02 AM PST	High Wind Watch	MTR	Marin, City and County of San Francisco, San Mateo, Santa Clara, Santa Cruz, Sonoma	11 hr
Jan 9, 2:17 PM PST	High Wind Warning	MTR	Monterey, San Mateo, Santa Clara, Santa Cruz	34 hr
Jan 9, 2:17 PM PST	Wind Advisory	MTR	Alameda, Contra Costa, Marin, Monterey, Napa, City and County of San Francisco and 4 more	34 hr
Jan 9, 2:39 PM PST	Flash Flood Watch	MTR	Marin, Monterey, Napa, San Mateo, Santa Clara, Santa Cruz and 1 more	37 hr

Nearby

Areal Flood Warnings in California, 2017 Every areal 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.