Alert archive / California / High Wind Warnings in 2023

High Wind Warning 4, NWS San Francisco Bay Area, CA

March 12, 202311 counties in California

NWS San Francisco Bay Area, CA issued this high wind warning at Mar 12, 2023, 11:32 AM PDT for 11 counties in California. It took effect at Mar 13, 2023, 11:00 PM PDT. It was in force for 21 hr. 60 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Mar 12, 2023, 11:32 AM PDT (18:32 UTC)
In effect from
Mar 13, 2023, 11:00 PM PDT
Expired
Mar 14, 2023, 8:09 PM PDT
In force
21 hr
Issued by
NWS San Francisco Bay Area, CA

Counties Alameda County, CA, City and County of San Francisco, CA, Contra Costa County, CA, Marin County, CA, Monterey County, CA, Napa County, CA, San Benito County, CA, San Mateo County, CA, Santa Clara County, CA, Santa Cruz County, CA, Sonoma County, CA

The radar

The San Francisco radar (KMUX), 46 km from the middle of the area, began a volume at 18:31 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.

What was reported inside it

TimeReportWhereRemark
Mar 14, 3:30 AM PDTNON-TSTM WND DMG1 Wnw Santa Rosa, CATREE DOWN ON ORCHARD ST NEAR SPENCER AVE, TAKING DOWN POWER LINES.
Mar 14, 4:00 AM PDTFLOOD1 Sse Occidental, CAMUDSLIDE REPORTED TO BLOCK PART OF BOHEMIAN HWY, REPORT MENTIONED IT WAS CONTINUING TO SLIDE.
Mar 14, 4:10 AM PDTFLOOD1 Nne Interlaken, CAHWY 152 CLOSED AT CASSERLY TO THE SANTA CLARA COUNTY LINE FOR SLIDES.
Mar 14, 4:10 AM PDTFLOOD1 Ssw Interlaken, CAHWY 152 CLOSED AT HOLOHAN FOR FLOODING.
Mar 14, 5:31 AM PDTFLOOD3 Ene Marina, CAWATER OVER THE RDWY / STEAD STREAM FLOWING. FELT LIKE IT WAS PUSHING VEHS INTO THE FIELD.
Mar 14, 7:10 AM PDTFLOOD4 Se Del Monte Forest, CATREE DOWN, BLOCKING HALF OF THE WB LANES.
Mar 14, 7:10 AM PDTNON-TSTM WND DMG4 Se Del Monte Forest, CATREE DOWN, BLOCKING HALF OF THE WB LANES.
Mar 14, 7:12 AM PDTFLOOD2 Ese Petaluma, CATREE DOWN BLOCKING ROAD WAY.
Mar 14, 7:12 AM PDTNON-TSTM WND DMG2 Ese Petaluma, CATREE DOWN BLOCKING ROAD WAY.
Mar 14, 7:30 AM PDTFLOOD3 Ssw Scotts Valley, CAFLOODING BOTH SOUTHBOUND LANES AT EL RANCHO / LA MADRONA BRIDGE.
Mar 14, 8:15 AM PDTNON-TSTM WND DMG2 Wnw San Jose, CALARGE TREE FELL ON NB CA 87 JUST SOUTH OF I 280 INTERCHANGE.
Mar 14, 8:24 AM PDTFLOOD2 S Portola Valley, CAMUDSLIDE COVERING BOTH LANES.
Mar 14, 8:26 AM PDTFLOOD1 Sw Colma, CACORRECTS PREVIOUS FLOOD REPORT FROM 1 SW COLMA. HICKEY BLVD ONRAMP TO NB I 280 FLOODED.
Mar 14, 8:26 AM PDTFLOOD1 Sw Colma, CAHICKEY BLVD ONRAMP TO NB I 280 FLOODED.
Mar 14, 8:49 AM PDTFLOOD2 Ne Aromas, CAMUDSLIDE.
Mar 14, 8:50 AM PDTNON-TSTM WND DMG2 Se Del Monte Forest, CATREE DOWN ON ROAD.
Mar 14, 9:00 AM PDTFLOOD5 S Occidental, CACAR STUCK ON FLOODED ROAD.
Mar 14, 9:11 AM PDTFLOOD4 Sse Gilroy, CA101 NB LANES CLOSED DUE TO FLOODING FROM SARGENT TO HWY 25.
Mar 14, 9:40 AM PDTNON-TSTM WND GST 785 N Lagunitas-Forest Kn, CAMESONET STATION PG133 PABLO POINT.
Mar 14, 9:40 AM PDTNON-TSTM WND GST 831 Wsw Woodacre, CAMESONET STATION PG550 1.3 W WOODACRE (PGE).
Mar 14, 9:50 AM PDTNON-TSTM WND GST 607 Sse Del Monte Forest, CAMESONET STATION PG858 MT. DEVIN ROAD.
Mar 14, 9:53 AM PDTNON-TSTM WND DMG2 E Del Monte Forest, CATREE AND POWER LINES DOWN ON CUESTA VISTA DR.
Mar 14, 9:53 AM PDTNON-TSTM WND DMG2 Ene Del Monte Forest, CATREE DOWN ON SKYLINE DR BETWEEN PINEHILL WAY AND FOREST RIDGE RD, BLOCKING THE ROAD.
Mar 14, 9:54 AM PDTNON-TSTM WND DMG7 S Del Monte Forest, CAPOWER LINES DOWN ACROSS ROAD WAYS.
Mar 14, 9:55 AM PDTNON-TSTM WND DMG6 S Del Monte Forest, CAROAD CLOSURE DUE TO POWER LINES DOWN.
Mar 14, 9:57 AM PDTNON-TSTM WND DMG3 Se Del Monte Forest, CALARGE TREE LIMB DANGLING OVER ROAD WAY.
Mar 14, 10:00 AM PDTNON-TSTM WND GST 623 Nne Bolinas, CAMESONET STATION PG489 3.4 NE BOLINAS (PGE).
Mar 14, 10:00 AM PDTNON-TSTM WND GST 6313 Sw Carmel Valley Vil, CAMESONET STATION PG471 12.7 SW CARMEL VALLEY VILL (PGE).
Mar 14, 10:00 AM PDTNON-TSTM WND GST 684 S Carmel Valley Vill, CAMESONET STATION PG704 LONG RIDGE.
Mar 14, 10:00 AM PDTNON-TSTM WND GST 684 Sw Los Altos Hills, CAMESONET STATION PG003 BLACK MOUNTAIN.
Mar 14, 10:09 AM PDTFLOOD3 Sw Castroville, CAFLOODWATERS MOVING OVER MONTE ROAD NORTH OF SALINAS RIVER. VIA TWITTER.
Mar 14, 10:10 AM PDTNON-TSTM WND GST 934 Nw Lagunitas-Forest K, CAMESONET STATION 340PG ROAD TO RANCHES.
Mar 14, 10:20 AM PDTNON-TSTM WND GST 6712 Sw Carmel Valley Vil, CAMESONET STATION PG409 12.4 SW CARMEL VALLEY VILL (PGE).
Mar 14, 10:20 AM PDTNON-TSTM WND DMG1 Ne Del Monte Forest, CACA 68 CLOSED AT SFB MORSE DR DUE TO TREE DOWN IN THE ROADWAY.
Mar 14, 10:30 AM PDTNON-TSTM WND GST 627 Ene Carmel Valley Vil, CAMESONET STATION PG948 CORRAL DE CIELO ROAD.
Mar 14, 10:30 AM PDTNON-TSTM WND GST 815 Ssw Los Altos Hills, CAMESONET STATION GW3142 LA HONDA.
Mar 14, 10:39 AM PDTFLOOD3 Ese Temelec, CAROAD CLOSED AT CA 121 AND CA 12 DUE TO FLOODING.
Mar 14, 10:40 AM PDTNON-TSTM WND GST 803 Ssw Saratoga, CAMESONET STATION 100PG STUART RIDGE.
Mar 14, 10:46 AM PDTFLOOD2 N Cloverdale, CAROADWAY FLOODING AT ON-RAMP ONTO SR-128.
Mar 14, 10:46 AM PDTNON-TSTM WND GST 6615 Se Carmel Valley Vil, CAMESONET STATION TT320 LPF01 PORTABLE.
Mar 14, 10:47 AM PDTNON-TSTM WND DMG2 E Del Monte Forest, CATREE DOWN ON BOTH LANES.
Mar 14, 10:49 AM PDTFLOOD15 Ssw Carmel Valley Vi, CAROADWAY FLOODING, WATER IN LANES.
Mar 14, 10:51 AM PDTFLOOD1 E Day Valley, CAMUDSLIDE COVERING ACCESS TO THE MAIN ROAD.
Mar 14, 11:00 AM PDTNON-TSTM WND GST 611 Wsw Del Monte Forest, CAMESONET STATION EW8505 PEBBLE BEACH.
Mar 14, 11:00 AM PDTNON-TSTM WND GST 617 Ene Carmel Valley Vil, CAMESONET STATION PG318 7.0 E CARMEL VALLEY VILL (PGE).
Mar 14, 11:00 AM PDTNON-TSTM WND GST 665 Nw Inverness, CAMESONET STATION 152PG DUCK COVE ROAD.
Mar 14, 11:05 AM PDTNON-TSTM WND GST 975 Ese Lexington Hills, CAMESONET STATION SJS04 LOMA PRIETA.
Mar 14, 11:10 AM PDTNON-TSTM WND DMG1 Ssw Saratoga, CATREE DOWN ON HOME ON LUTHERIA WAY. NO INJURIES.
Mar 14, 11:20 AM PDTNON-TSTM WND GST 613 Sw Monte Sereno, CAMESONET STATION PG050 EL SERENO.
Mar 14, 11:20 AM PDTNON-TSTM WND GST 622 W Mill Valley, CAMESONET STATION PG006 2.1 W MILL VALLEY (PGE).
Mar 14, 11:20 AM PDTNON-TSTM WND GST 762 Nne Lexington Hills, CAMESONET STATION PG998 PRIEST ROCK.
Mar 14, 11:20 AM PDTNON-TSTM WND GST 902 Nw Lucas Valley-Marin, CAMESONET STATION PG123 LUCAS VALLEY.
Mar 14, 11:25 AM PDTNON-TSTM WND DMGDaly City, CALARGE TREE BLOCKING NB JUNIPERO SERRA BLVD AT D ST.
Mar 14, 11:26 AM PDTNON-TSTM WND DMG1 W Cambrian Park, CATREE DOWN IN THE OFFRAMP FROM CA 85 NB TO BASCOM AVE.
Mar 14, 11:27 AM PDTNON-TSTM WND DMG2 Wnw Ben Lomond, CATREE DOWN ON ROADWAY.
Mar 14, 11:28 AM PDTNON-TSTM WND DMG1 W Forestville, CAAPPROXIMATE LOCATION. TREE FELL ON MARTINELLI RD BETWEEN VELLUTINI AND CA 116, BLOCKING THE ROAD. VIA TWITTER.
Mar 14, 11:33 AM PDTNON-TSTM WND GST 67Lucas Valley-Marinwood, CAMESONET STATION NBRC1 BIG ROCK.
Mar 14, 11:40 AM PDTNON-TSTM WND GST 601 Sse Highlands, CAMESONET STATION 048PG LOOP ROAD.
Mar 14, 11:40 AM PDTNON-TSTM WND GST 639 Se Livermore, CAMESONET STATION PG101 MENDENHALL SPRINGS.
Mar 14, 11:40 AM PDTNON-TSTM WND GST 655 Nne Day Valley, CAMESONET STATION 049PG LOMA CHIQUITA.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Oakland, CA (KOAK), launched 12:00Z, 6.5 hours before the alert went out and 24 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-pSkew-T log-p diagram, Oakland, CA at 12:00Z on 2023-03-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 11 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Oakland, CA at 12:00Z on 2023-03-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 173 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
11 J/kg
Mixed-layer CIN
-42 J/kg
Mixed-layer LCL
571 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
173 m²/s²
0-3 km storm-relative helicity
266 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

011 
WWUS76 KMTR 121832
NPWMTR

URGENT - WEATHER MESSAGE
National Weather Service San Francisco Bay Area
1132 AM PDT Sun Mar 12 2023

CAZ006-502>506-508>510-512>518-528>530-130500-
/O.UPG.KMTR.HW.A.0002.230314T0600Z-230315T1200Z/
/O.NEW.KMTR.HW.W.0004.230314T0600Z-230315T1200Z/
San Francisco-Marin Coastal Range-Sonoma Coastal Range-
North Bay Interior Mountains-
Coastal North Bay...Including Point Reyes National Seashore-
North Bay Interior Valleys-San Francisco Bay Shoreline-
San Francisco Peninsula Coast-East Bay Interior Valleys-
Santa Cruz Mountains-Santa Clara Valley...including San Jose-
Eastern Santa Clara Hills-East Bay Hills-
Southern Salinas Valley...Arroyo Seco...and Lake San Antonio-
Santa Lucia Mountains and Los Padres National Forest-
Mountains of San Benito and Interior Monterey County including
Pinnacles National Park-
Northern Salinas Valley...Hollister Valley...and Carmel Valley-
Northern Monterey Bay-Southern Monterey Bay and Big Sur Coast-
1132 AM PDT Sun Mar 12 2023

...HIGH WIND WARNING IN EFFECT FROM 11 PM MONDAY TO 5 AM PDT
WEDNESDAY...

* WHAT...Southerly winds 20 to 40 mph with gusts 50 mph in the
  valleys. Gusts 55 to 70 mph immediate coastline and hills above
  1000 feet.

* WHERE...San Francisco Bay Area and Central Coast. 

* WHEN...From 11 PM Monday to 5 AM PDT Wednesday.

* IMPACTS...Damaging winds will blow down trees and power lines. 
  Widespread power outages are expected. Travel will be 
  difficult, especially for high profile vehicles.

* ADDITIONAL DETAILS...Southerly winds will quickly increase
  during the overnight hours of Monday into early Tuesday morning
  as the first slug of energy arrives with the atmospheric river.
  Winds may ease slightly for a time on Tuesday then turn
  southwest as strong surface low pressure passes over the region.
  Expect downed trees and limbs to lead to renewed power outages
  across the region.
  

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People should avoid being outside in forested areas and around
trees and branches. If possible, remain in the lower levels of
your home during the windstorm, and avoid windows. Use caution if
you must drive.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/mtr
5 follow-up statements
222 
WWUS76 KMTR 130314
NPWMTR

URGENT - WEATHER MESSAGE
National Weather Service San Francisco Bay Area
814 PM PDT Sun Mar 12 2023

CAZ006-502>506-508>510-512>518-528>530-131300-
/O.CON.KMTR.HW.W.0004.230314T0600Z-230315T1200Z/
San Francisco-Marin Coastal Range-Sonoma Coastal Range-
North Bay Interior Mountains-
Coastal North Bay...Including Point Reyes National Seashore-
North Bay Interior Valleys-San Francisco Bay Shoreline-
San Francisco Peninsula Coast-East Bay Interior Valleys-
Santa Cruz Mountains-Santa Clara Valley...including San Jose-
Eastern Santa Clara Hills-East Bay Hills-
Southern Salinas Valley...Arroyo Seco...and Lake San Antonio-
Santa Lucia Mountains and Los Padres National Forest-
Mountains of San Benito and Interior Monterey County including
Pinnacles National Park-
Northern Salinas Valley...Hollister Valley...and Carmel Valley-
Northern Monterey Bay-Southern Monterey Bay and Big Sur Coast-
814 PM PDT Sun Mar 12 2023

...HIGH WIND WARNING REMAINS IN EFFECT FROM 11 PM MONDAY TO 5 AM
PDT WEDNESDAY...

* WHAT...Southerly winds 20 to 40 mph with gusts 50 mph in the 
  valleys. Gusts 55 to 70 mph immediate coastline and hills 
  above 1000 feet.

* WHERE...San Francisco Bay Area and Central Coast.

* WHEN...From 11 PM Monday to 5 AM PDT Wednesday.

* IMPACTS...Damaging winds will blow down trees and power lines.
  Widespread power outages are expected and roadways could be
  blocked by downed trees. Travel will be difficult, especially 
  for high profile vehicles.

* ADDITIONAL DETAILS...Southerly winds will quickly increase 
  during the overnight hours of Monday into early Tuesday 
  morning as the first slug of energy arrives with the 
  atmospheric river. Winds may ease slightly for a time on 
  Tuesday then turn southwest as strong surface low pressure 
  passes over the region. Expect downed trees and limbs to lead 
  to renewed power outages across the region.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People should avoid being outside in forested areas and around
trees and branches. If possible, remain in the lower levels of
your home during the windstorm, and avoid windows. Use caution if
you must drive.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/mtr
728 
WWUS76 KMTR 131039
NPWMTR

URGENT - WEATHER MESSAGE
National Weather Service San Francisco Bay Area
339 AM PDT Mon Mar 13 2023

CAZ006-502>506-508>510-512>518-528>530-132100-
/O.CON.KMTR.HW.W.0004.230314T0600Z-230315T1200Z/
San Francisco-Marin Coastal Range-Sonoma Coastal Range-
North Bay Interior Mountains-
Coastal North Bay...Including Point Reyes National Seashore-
North Bay Interior Valleys-San Francisco Bay Shoreline-
San Francisco Peninsula Coast-East Bay Interior Valleys-
Santa Cruz Mountains-Santa Clara Valley...including San Jose-
Eastern Santa Clara Hills-East Bay Hills-
Southern Salinas Valley...Arroyo Seco...and Lake San Antonio-
Santa Lucia Mountains and Los Padres National Forest-
Mountains of San Benito and Interior Monterey County including
Pinnacles National Park-
Northern Salinas Valley...Hollister Valley...and Carmel Valley-
Northern Monterey Bay-Southern Monterey Bay and Big Sur Coast-
339 AM PDT Mon Mar 13 2023

...HIGH WIND WARNING REMAINS IN EFFECT FROM 11 PM THIS EVENING TO
5 AM PDT WEDNESDAY...

* WHAT...Southerly winds 20 to 40 mph with gusts 50 mph in the 
  valleys. Gusts 55 to 70 mph immediate coastline and hills 
  above 1000 feet.

* WHERE...San Francisco Bay Area and Central Coast.

* WHEN...From 11 PM Monday to 5 AM PDT Wednesday.

* IMPACTS...Damaging winds will blow down trees and power lines. 
  Widespread power outages are expected and roadways could be 
  blocked by downed trees. Travel will be difficult, especially 
  for high profile vehicles.

* ADDITIONAL DETAILS...Southerly winds will quickly increase 
  during the overnight hours of Monday into early Tuesday 
  morning as the first slug of energy arrives with the 
  atmospheric river. Winds may ease slightly for a time on 
  Tuesday then turn southwest as strong surface low pressure 
  passes over the region. Expect downed trees and limbs to lead 
  to renewed power outages across the region.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People should avoid being outside in forested areas and around
trees and branches. If possible, remain in the lower levels of
your home during the windstorm, and avoid windows. Use caution if
you must drive.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/mtr
558 
WWUS76 KMTR 132049
NPWMTR

URGENT - WEATHER MESSAGE
National Weather Service San Francisco Bay Area
149 PM PDT Mon Mar 13 2023

CAZ006-502>506-508>510-512>518-528>530-140900-
/O.CON.KMTR.HW.W.0004.230314T0600Z-230315T1200Z/
San Francisco-Marin Coastal Range-Sonoma Coastal Range-
North Bay Interior Mountains-
Coastal North Bay...Including Point Reyes National Seashore-
North Bay Interior Valleys-San Francisco Bay Shoreline-
San Francisco Peninsula Coast-East Bay Interior Valleys-
Santa Cruz Mountains-Santa Clara Valley...including San Jose-
Eastern Santa Clara Hills-East Bay Hills-
Southern Salinas Valley...Arroyo Seco...and Lake San Antonio-
Santa Lucia Mountains and Los Padres National Forest-
Mountains of San Benito and Interior Monterey County including
Pinnacles National Park-
Northern Salinas Valley...Hollister Valley...and Carmel Valley-
Northern Monterey Bay-Southern Monterey Bay and Big Sur Coast-
149 PM PDT Mon Mar 13 2023

...HIGH WIND WARNING REMAINS IN EFFECT FROM 11 PM THIS EVENING TO
5 AM PDT WEDNESDAY...

* WHAT...Southerly winds 20 to 40 mph with gusts 50 mph in the 
  valleys. Gusts 55 to 70 mph immediate coastline and hills 
  above 1000 feet.

* WHERE...San Francisco Bay Area and Central Coast of California.

* WHEN...From 11 PM Monday to 5 AM PDT Wednesday.

* IMPACTS...Damaging winds will blow down trees and power lines. 
  Widespread power outages are expected and roadways could be 
  blocked by downed trees. Travel will be difficult, especially 
  for high profile vehicles.

* ADDITIONAL DETAILS...Southerly winds will quickly increase
  during the overnight hours of Monday into early Tuesday morning
  as the atmospheric river arrives. Winds may ease slightly for a
  time on Tuesday then turn southwest as strong surface low 
  pressure passes over the region. Expect downed trees and limbs 
  to lead to renewed power outages across the region.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People should avoid being outside in forested areas and around
trees and branches. If possible, remain in the lower levels of
your home during the windstorm, and avoid windows. Use caution if
you must drive.

&&

$$

MTR

For more information from the National Weather Service visit
https://weather.gov/mtr
096 
WWUS76 KMTR 140808
NPWMTR

URGENT - WEATHER MESSAGE
National Weather Service San Francisco Bay Area
108 AM PDT Tue Mar 14 2023

CAZ006-502>506-508>510-512>518-528>530-150600-
/O.EXT.KMTR.HW.W.0004.000000T0000Z-230315T0600Z/
San Francisco-Marin Coastal Range-Sonoma Coastal Range-
North Bay Interior Mountains-
Coastal North Bay...Including Point Reyes National Seashore-
North Bay Interior Valleys-San Francisco Bay Shoreline-
San Francisco Peninsula Coast-East Bay Interior Valleys-
Santa Cruz Mountains-Santa Clara Valley...including San Jose-
Eastern Santa Clara Hills-East Bay Hills-
Southern Salinas Valley...Arroyo Seco...and Lake San Antonio-
Santa Lucia Mountains and Los Padres National Forest-
Mountains of San Benito and Interior Monterey County including
Pinnacles National Park-
Northern Salinas Valley...Hollister Valley...and Carmel Valley-
Northern Monterey Bay-Southern Monterey Bay and Big Sur Coast-
108 AM PDT Tue Mar 14 2023

...HIGH WIND WARNING NOW IN EFFECT UNTIL 11 PM PDT THIS EVENING...

* WHAT...Southerly winds 20 to 40 mph with gusts 50 mph in the 
  valleys. Gusts 55 to 70 mph immediate coastline and hills 
  above 1000 feet.

* WHERE...San Francisco Bay Area and Central Coast of California.

* WHEN...Until 11 PM PDT this evening.

* IMPACTS...Damaging winds will blow down trees and power lines. 
  Widespread power outages are expected and roadways could be 
  blocked by downed trees. Travel will be difficult, especially 
  for high profile vehicles.

* ADDITIONAL DETAILS...Southerly winds will rapidly increase
  Tuesday morning as the atmospheric river arrives. Expect downed
  trees and limbs to lead to renewed power outages across the 
  region.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People should avoid being outside in forested areas and around
trees and branches. If possible, remain in the lower levels of
your home during the windstorm, and avoid windows. Use caution if
you must drive.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/mtr
457 
WWUS76 KMTR 150309
NPWMTR

URGENT - WEATHER MESSAGE
National Weather Service San Francisco Bay Area
809 PM PDT Tue Mar 14 2023

CAZ006-502>506-508>510-512>518-528>530-150415-
/O.CAN.KMTR.HW.W.0004.000000T0000Z-230315T0600Z/
San Francisco-Marin Coastal Range-Sonoma Coastal Range-
North Bay Interior Mountains-
Coastal North Bay...Including Point Reyes National Seashore-
North Bay Interior Valleys-San Francisco Bay Shoreline-
San Francisco Peninsula Coast-East Bay Interior Valleys-
Santa Cruz Mountains-Santa Clara Valley...including San Jose-
Eastern Santa Clara Hills-East Bay Hills-
Southern Salinas Valley...Arroyo Seco...and Lake San Antonio-
Santa Lucia Mountains and Los Padres National Forest-
Mountains of San Benito and Interior Monterey County including
Pinnacles National Park-
Northern Salinas Valley...Hollister Valley...and Carmel Valley-
Northern Monterey Bay-Southern Monterey Bay and Big Sur Coast-
809 PM PDT Tue Mar 14 2023

...HIGH WIND WARNING IS CANCELLED...

Winds have decreased to below warning levels. However gusty winds
remain possible overnight. Please us caution however as saturated
soil could lead to additional downed trees and power outages.

$$

For more information from the National Weather Service visit
https://weather.gov/mtr

What forecasters said that day

The local office's own words before this high wind 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 high wind warning went out at Mar 12, 10:24 AM PDT, 1 hour 8 minutes earlier.

Area forecast discussion, Mar 12, 10:24 AM PDT, 1 hour 8 minutes before
Area Forecast Discussion
National Weather Service San Francisco Bay Area
1024 AM PDT Sun Mar 12 2023

.SYNOPSIS...Atmospheric river arrives Monday night into Tuesday.
Wind and water impacts are expected with downed trees, heavy rain,
and additional flooding. Power outages and travel impacts are
expected and could last well beyond the next several days.

&&

...Atmospheric River brings Wind and Water Impacts Monday Night
into Tuesday...

.DISCUSSION...as of 08:55 AM PDT Sunday...

Radar and satellite currently show a band of light to moderate
convective rainshowers over the San Mateo Peninsula, South Bay,
and Alameda county. There has been a lightning strike or two seen
with this as well, meaning locally moderate/heavy rain showers
are possible with this band of convection. Surface observations
depict around 0.25 to 0.75 inches of rain that has fallen from
this band. These totals might be low amounts but the ground
saturation has reached its limit for most of central and northern
CA. There is a report of a mud slide on HWY 1 by Moss Beach where
this rain is moving over, so be careful on the commute this
morning.

High res models depict this band moving out of the CWA in the
next couple hours, as satellite does show drier air right behind
this band over the waters. A quick break in the clouds and rain
for mid day today over the SF Bay and south. This will allow
surface temperatures to warm. Confidence in scattered to numerous
mild convection this afternoon has risen this morning. Better
chances for stronger convection lies in eastern counties(Alameda,
San Benito, Contra Costa, and Napa) that are closer to the central
valley, where the best chances for stronger afternoon convection
lies. This stronger convection is fueled by a low CAPE moderate
shear environment which could produce small hail, gusty winds, and
brief heavy down pours.

A PVA is spotted ~300 miles off the coast of the North
Bay/Mendocino County. This is forecasted to move primarily over
Mendocino county and north, however light to moderate stratiform
rain will likely trail down into the North Bay this afternoon and
evening, slowly dropping around 0.25 to 1 inches. Accumulations
remain lower, however soils are extremely saturated and this could
still lead to some localized flooding.

Satellite shows the next AR system maturing just north of Hawaii
this morning, leading to increased confidence in intensities of
this next system. That is the area of focus for this next forecast
package.

&&

.PREV DISCUSSION...as of 03:43 AM PDT Sunday...

Key Points--

* Isolated thunderstorms today with locally heavy rainfall possible
* Moderate strength Atmospheric River Monday night into Tuesday
* High-end wind and water impacts possible beginning Monday night
* Flooding of streets, rivers, and streams is likely
* Flash flooding and debris flows are possible in complex terrain
* Downed trees expected and prolonged power outages may occur
* Difficult to impossible travel for some areas starting Monday night

Technical Discussion--

Today and Tonight:

A low amplitude flow pattern will prevail aloft with several
perturbations embedded within the mean flow. A stronger impulse now
evident in moisture channel imagery will trek towards NorCal this
morning with an associated upper jet max landfalling on the Central
Coast. These synoptic-scale lifting mechanisms will help prime the
thermodynamic environment for showers and isolated thunderstorms
today as mid-level lapse rates steepen to between 6.5 and 7 degrees
Celsius per kilometer by late morning to early afternoon. Warm low-
level thermal advection will also be present across the Bay Area as
a warm front lifts north across the region. This feature combined
with local winds and outflows should generate at least modest
forcing for ascent with corresponding potential for showers and
isolated thunderstorms through the afternoon hours. While the
greatest surface-based instability should exist towards the Central
Valley (SBCAPE increasing to over 300 J/kg by 21Z) weaker
instability is present locally over the North and East Bays and over
San Benito County. Some thunderstorm organization is also possible
(primarily near the Sacramento Valley) as effective bulk shear
values increase to around 30 kt. So look for scattered showers today
along with localized potential for a thunderstorm or two. The
primary hazards associated with any thunderstorms would be brief
locally heavy rain, gusty winds, hail, and occasional lightning.
Overall rain amounts today should be 0.25 inches or less but heavier
amounts expected over the North Bay Hills (~0.5-1 inch) and locally
in heavier showers and/or possible thunderstorms. And while showers
today shouldn't contribute to widespread flooding can't rule out
localized impacts given wet soils and high stream levels. Shower
chances will persist into tonight. High temperatures today will
generally be in the 60-65 degree range with slightly cooler readings
(upper 50s) for the North Bay and near the immediate coastline.

Monday and Tuesday:

This is the primary period of concern as an Atmospheric River (AR)
impacts the region. Models remain steadfast on landfalling the
system on Monday night into Tuesday. Integrated Vapor Transport
looks to peak in the 600-700 kg/m*s range with an accompanying 60 kt
low-level jet. This suggests a moderate strength AR. However it's
noted there is a small (5-10 percent) probability the AR could reach
into the low-end strong category. Regardless it does appear that a
corridor of rich moisture will again focus on our area with
increased potential for wind and water related impacts. And while
some differences are noted in landfall location and intensity, a
consensus of deterministic models, ensembles, and associated climate
tools all point towards the likelihood of notable impacts for our
area.

Water related impacts are sure to occur given antecedent conditions
of super-saturated soils and already elevated river and creek
levels. Additional rainfall generated via efficient warm rain
processes will allow the threat for urban, river, and flash flooding
to increase and potentially eclipse impacts from the previous AR
event. This will also exacerbate river flooding already ongoing over
Monterey County. A Flood Watch remains in effect from Monday evening
into Tuesday night region-wide. In addition to flooding, the
potential for shallow landslides and debris flows will also increase
with travel impacts likely to develop starting Monday night.
Hazardous travel conditions are likely to exist into at least
Tuesday and potentially beyond for some areas. Postpone travel if
possible and remember to NEVER drive through flooded roadways. Turn
around, don't drown!

Wind impacts are also expected given saturated soils and a strong
southerly low-level jet associated with the AR. Ensemble based
situational awareness tools point towards the potential for extreme
values compared to climatology with NBM 50th and 75th percentile
wind gust magnitudes eclipsing 50 mph for ridges, gaps, and perhaps
some coastal locations. A High Wind Watch remains in effect for
Monday night into Tuesday night. Be prepared for the likelihood of
downed trees on Monday night into Tuesday with prolonged power
outages a distinct possibility.

Now is the time to prepare. Get gas for generators, clean storm
drains and gutters, tie down or move loose objects inside. Make sure
you have extra supplies, food, and necessary medications in case
roads are closed or power outages last for several days. Pack a "go
bag" to help evacuate quickly if you live in a flood prone location.
Prolonged and long-lasting impacts are possible from this storm.

Wednesday through Saturday:

A drying trend on Wednesday into Thursday should allow a window for
storm cleanup. Rain chances look to return by Friday or the weekend
but ensemble spread leads to low confidence in timing. Rain amounts
look to be on the light side. Temperatures should start out cool
with a moderating trend towards the weekend.

&&

.AVIATION...as of 10:20 AM Sunday...For the 18Z TAFs. Scattered
showers continue throughout the TAF period with a lull in coverage
early on Monday. Most intense cells over the North Bay and East Bay
creating IFR conditions, with the remainder of the region seeing VFR-
MVFR conditions. A generally southerly pattern continues with the
wind speeds up to 15-20 knots. Conditions expected to remain MVFR
for most terminals with patches of IFR almost certain in the
mountain ranges and the North Bay seeing the highest probabilities
(over 70%) of the development of IFR ceilings in the valley regions.
Next major rain system expected Monday night after the end of the
TAF period.

Vicinity of SFO...Scattered showers through the TAF period.
Southerly winds through the TAF period, with wind gusts up to 25
knots this afternoon. A moderate chance (40-50% probability) of IFR
ceilings through the day into the overnight hours, otherwise
generally MVFR.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Shower activity increases this evening and
persists overnight. Generally VFR-MVFR, with a low confidence (20-
30% probability) of IFR ceilings developing at MRY overnight. Winds
will be quite strong from a more southerly direction, with gusts at
SNS up to 20 knots.

&&

.CLIMATE...

Rain Records for some of our official Climate Sites

Climate Site 	March 13 Record 			March 14 Record

Santa Rosa		2.74" 1983 					1.42" 1942
Kentfield 		4.00" 1983 					4.17" 2012
Napa dwntown 	2.33" 1983 					3.30" 2003
Livermore dwtn 	1.10" 1919 					0.88" 2020
SF downtown 	2.54" 1889 					1.68" 1952
Oakland dwtn 	1.28" 1975 					2.46" 2012
San Jose 		1.15" 1998 					1.40" 1952
Salinas arprt 	0.67" 1983 					1.01" 1948

&&

.MARINE...as of 10:23 AM PDT Sunday...Periodic light rain
continues with southerly to southwesterly  winds through late
Tuesday into Wednesday. A strengthening low  pressure system over
the Pacific brings heavy rain and wind to the coastal waters and
bays late Monday through Tuesday. A Gale Watch is in effect for
the coastal waters late Monday night and  Tuesday. Winds shifting
back to northwesterly mid week then  shifting to southerly ahead
of the next low pressure system  bringing rain late in the week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tday...SCA...Mry Bay from 4 PM
             SCA...Pigeon Pt to Pt Pinos 0-10 nm
             SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm

&&

PUBLIC FORECAST: SPM
AVIATION: DialH
MARINE: DialH

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In the hours before

Special weather statement, Mar 12, 8:37 AM PDT, 2 hours 55 minutes before
Special Weather Statement
National Weather Service San Francisco CA
837 AM PDT Sun Mar 12 2023

CAZ508-509-512-515-121615-
East Bay Hills CA-San Fransisco Peninsula Coast CA-
Santa Cruz Mountains CA-San Francisco Bay Shoreline CA-
837 AM PDT Sun Mar 12 2023

...A strong thunderstorm will impact portions of southwestern Alameda
and northern San Mateo Counties through 915 AM PDT...

At 837 AM PDT, Doppler radar was tracking a strong thunderstorm over
Hillsborough, or over San Mateo, moving northeast at 35 mph.

HAZARD...Pea size hail.

SOURCE...Radar indicated.

IMPACT...Minor damage to outdoor objects is possible.

Locations impacted include...
Oakland, Fremont, Hayward, San Mateo, San Leandro, Redwood City,
Alameda, Union City, South San Francisco, San Bruno, Pacifica, Foster
City, Burlingame, San Carlos, Belmont, Millbrae, San Lorenzo, Castro
Valley, Half Moon Bay and Hillsborough.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3767 12238 3765 12238 3772 12225 3774 12225
      3774 12222 3775 12221 3776 12222 3775 12223
      3776 12227 3782 12220 3758 12197 3753 12218
      3755 12213 3756 12213 3756 12214 3751 12221
      3746 12241 3756 12250
TIME...MOT...LOC 1537Z 239DEG 32KT 3755 12236

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...<30 MPH

DialH
Local storm report, Mar 12, 9:43 AM PDT, 1 hour 49 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
943 AM PDT SUN MAR 12 2023

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

0930 AM     FLOOD            2 SW PAJARO             36.88N 121.77W
03/12/2023                   MONTEREY           CA   PUBLIC

            HWY 1 IS CLOSED FROM SALINAS RD TO HWY 129
            DUE TO FLOODING.

&&

ED
Local storm report, Mar 12, 9:46 AM PDT, 1 hour 46 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
946 AM PDT SUN MAR 12 2023

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

0830 AM     FLOOD            1 WSW MONTARA           37.54N 122.52W
03/12/2023                   SAN MATEO          CA   LAW ENFORCEMENT

            MUD SLID ON HWY 1 BLOCKING NB LANE.

&&

ED
Local storm report, Mar 12, 10:16 AM PDT, 1 hour 16 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
1016 AM PDT SUN MAR 12 2023

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

0910 AM     FLOOD            2 NW FREMONT            37.55N 122.02W
03/12/2023                   ALAMEDA            CA   LAW ENFORCEMENT

            FLOODING ON WB AND EB LNS OF 84, CAR STUCK
            IN WATER NB JSO THORTON.

&&

ED
Local storm report, Mar 12, 10:38 AM PDT, 54 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
1038 AM PDT SUN MAR 12 2023

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

1015 AM     FLOOD            1 NE WOODSIDE           37.44N 122.25W
03/12/2023                   SAN MATEO          CA   LAW ENFORCEMENT

            NUMEROUS REPORTS OF FLOODING ON HWY 280 FROM
            FARM HILL BLVD TO ALPINE RD.

&&

ED
Local storm report, Mar 12, 10:54 AM PDT, 38 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
1054 AM PDT SUN MAR 12 2023

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

1045 AM     FLOOD            FREMONT                 37.53N 122.00W
03/12/2023                   ALAMEDA            CA   PUBLIC

            HARD CLOSURE OF HWY 880 NB NEAR MOWRY AVE.

&&

ED

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 11, 4:38 PM PSTRiver Flood WarningMTRMonterey7 days
Mar 11, 4:54 PM PSTSpecial Weather StatementMTRAlameda36 min
Mar 12, 4:28 AM PDTGale WatchMTR16 hr
Mar 12, 8:37 AM PDTAreal Flood AdvisoryMTRSan Mateo, Santa Clara12 hr
Mar 12, 8:37 AM PDTSpecial Weather StatementMTRSan Mateo38 min
Mar 12, 9:34 AM PDTAreal Flood AdvisoryMTRAlameda, Contra Costa, Santa Clara11 hr
Mar 12, 11:48 AM PDTAreal Flood WarningMTRAlameda9 hr

Nearby

High Wind Warnings in California, 2023Every high wind warning in 2023

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.