Deepen low pressure approaching the coast caused gale to strong gale force wind gusts through the populated areas. Coastal mountains gusted to hurricane force.
Every event with a place to put it; 16 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS MTR wrote it up.
Deepen low pressure approaching the coast caused gale to strong gale force wind gusts through the populated areas. Coastal mountains gusted to hurricane force.
The local office's own words before the first event, 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 the first event at Feb 17, 3:48 AM PST, 2 hours 47 minutes earlier.
Area Forecast Discussion
National Weather Service San Francisco Bay Area
348 AM PST Fri Feb 17 2017
.SYNOPSIS...Periods of moderate to heavy rainfall along with
strong and gusty winds will impact the region through early
afternoon with lingering showers into Saturday morning. Additional
storm systems will result in widespread rainfall and increased
winds from Sunday night into Monday and again Tuesday night into
Wednesday. Cooler and drier weather conditions then develop late
next week.
&&
.DISCUSSION...as of 02:58 AM PST Friday...Precipitation
associated with a warm front over southern California continues to
spread northward this morning and is increasing in coverage and
intensity over the Central Coast. Meanwhile, a mid/upper level low
and associated surface low pressure continue to deepen off of the
central California coast. This system is forecast to shift toward
the San Francisco Bay Area through the morning and will result in
widespread rainfall developing across the entire region through
the morning hours. As the surface low deepens and approaches the
coast, southerly winds will increase and become strong and gusty
at times, especially over Monterey County with wind gusts in
excess of 60 MPH possible. Elsewhere, wind gust in excess of 45
MPH will be possible from the San Mateo Coast inland across the
East Bay and points inland/southward. Strongest winds will be
likely in the higher elevations. Thus, a High Wind Warning and
Wind Advisory remain in effect for portions of the region through
this afternoon. Winds will diminish as the surface low shifts
inland this afternoon/evening. Do expect rainfall to become
moderate to heavy at times as deeper atmospheric moisture across
southern California advects northward ahead of the approaching
mid/upper level low. Cannot rule out rainfall rates of 0.50" to
1.00" per hour at times through about 10 AM, especially along the
southwest facing slopes from the Santa Cruz Mountains southward.
These rainfall rates may pose a heightened threat for flash
flooding across burn scars from this past fire season. Folks
living in and around those areas should remain vigilant of heavy
downpours and potential for Flash Flood Warnings. Given the strong
winds and heavy rainfall...downed trees, isolated power outages,
rock/mud slides and debris flows will remain a threat through at
least early afternoon. In addition, cannot rule out embedded
thunderstorms across the Central Coast late this morning into the
early afternoon as the atmospheric becomes more unstable.
Widespread rain will tapper off during the afternoon hours as the
main system moves inland. As lingering moisture remains in place,
scattered showers will remain possible through tonight and into
Saturday morning. The forecast models do show a bit of a drying
trend from Saturday into Sunday morning, yet lingering showers now
look possible through the period. The good news is that organized,
widespread rainfall looks less likely and should allow for a periods
of dry conditions ahead of our next system set to arrive late Sunday.
The models are in decent agreement that a mid/upper level system
will bring another round of widespread rainfall to the North Bay
late Sunday and then across the remainder of the region Sunday night
into Monday morning. The greatest rainfall amounts will likely occur
over the North Bay and along the Coastal ranges with this system. A
third, less intense, system is then forecast to sweep through
Tuesday night into Wednesday. With each of these systems, do expect
increased winds and periods of moderate to locally heavy rainfall.
The accumulative effect from widespread rainfall associated with
these systems will increased the threat for flooding of area creeks,
streams as well as rock/mud slides, downed trees and typical hazards
the region has seen so far this winter season. Folks are urged to
stay up to date with the latest forecast as well as potential
watches and/or warnings.
Medium range models generally show a cooler, drier weather pattern
developing over the region by the second half of next week. Longer
range guidance currently suggests this trend to extend through late
February and potentially into early March.
&&
.AVIATION...As of 3:48 AM PST Friday...Rain is spreading northward
quickly this morning with metars reporting MVFR cigs/vsbys and local
IFR. Gusty SE winds. Low level wind shear likely in the Monterey Bay
area this morning.
Vicinity of KSFO...Lowering cigs with wet runways this morning. Winds
becoming gusty mid-late morning into this afternoon. Slowly improving
conditions expected by late afternoon and evening.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...Rain, gusty SE winds and lowering cigs this
morning. Gusty winds diminish by afternoon. VFR/MVFR.
&&
.MARINE...as of 02:58 AM PST Friday...A strong low pressure will
develop off the coastal waters this morning resulting in building
fresh swell and strengthening winds. Winds will reach gale force
conditions south of Pigeon Point this morning and increase
northward through the day. Hazardous conditions will persist into
Saturday with improving conditions by Sunday. Unsettled weather
remains for next week.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.Tday...Wind Advisory...San Francisco Bay Shoreline and Peninsula Coast
...Santa Cruz Mountains and Northern Monterey Bay
Flood Watch...Along and near the Salinas River from
Friday through this weekend
High Wind Warning...Santa Lucia/Los Padres NF...Northern Salinas
Valley...Hollister Valley...Carmel Valley...
Southern Monterey Bay and Big Sur Coast
GLW...Pigeon Pt to Pt Pinos 0-10 nm from 9 AM
SCA...Pt Arena to Pt Reyes 0-10 nm from 9 AM
SCA...Pt Reyes to Pigeon Pt 0-10 nm from 9 AM
SCA...Rough Bar Advisory for SF Bar until 3 PM
SCA...Pt Arena to Pigeon Pt 10-60 nm from 9 AM
SCA...SF Bay from 3 PM
SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm until 9 AM
GLW...Pt Pinos to Pt Piedras Blancas 0-10 nm from 9 AM
GLW...Pigeon Pt to Pt Piedras Blancas 10-60 nm from 9 AM
SCA...Mry Bay from 9 AM
&&
PUBLIC FORECAST: RGass
AVIATION: Canepa
MARINE: Dykema/Canepa
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www.youtube.com/nwsbayareaThe national radar mosaic for the moment the first event began.
15 high wind, 1 debris flow, 1 heavy rain, 1 strong wind. Local standard time, as filed.
Power pole and lines down old stage road at Natividad.
Trees blown down blocking entire roadway...Old Stage Rd at Calle El Rosario.
Trees and power lines blown down across Strawberry Cyn Rd.
Tree blown down blocking east bound lane HWY 68 at Laureles Grade.
Power lines in the road Seymour St at Cooper St.
Mudslide blocking north bound lanes Hwy 1 at Mesa Rd.
Power lines and pole blown down in roadway Cooper Rd at Nashua Rd.
Power line and trees in roadway...White Rd.
Tree and power lines down in the road...Blackie Rd at HWY 101.
Tree down blocking both lanes of Lewis Rd at San Miguel Cyn Rd.
Tree down blocking northbound lane HWY 1 at Moss Landing Rd.
Tree blown down 30 to 40 ft tall over 2 lanes of HWY 280 at San Bruno Ave.
Spotter reported 0.5 inches measured between 10:15am and 11:15am.
Tree down on Canyon Dr.
Winds have picked up...mainly from the southeast...over the past hour or so.
Medium sized tree fell over, blocking on ramp to Automall Pkwy.
Two trees with wires down across Fort Rd.
Large tree down blocking entire roadway Old Sonoma Rd between Duhig and Buhman.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2017Every state in 2017This day in weather historyWarnings in California, February 2017
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 683643, 683645, 683646, 683648, 683649, 683650, 683651, 683652, 683654, 683656, 683657, 683659, 683642, 683660, 683661, 683662, 683664, 683665.