Alert archive / California / Fire Weather Watches in 2021
Fire Weather Watch 7, NWS San Francisco Bay Area, CA
NWS San Francisco Bay Area, CA issued this fire weather watch at Oct 7, 2021, 2:21 PM PDT for 7 counties in California. It took effect at Oct 10, 2021, 11:00 PM PDT. It was in force for .
The area
The counties it named.
The facts
- Issued
- Oct 7, 2021, 2:21 PM PDT (21:21 UTC)
- In effect from
- Oct 10, 2021, 11:00 PM PDT
- Expired
- Oct 10, 2021, 3:03 AM PDT
- In force
- Issued by
- NWS San Francisco Bay Area, CA
Counties Alameda County, CA, Contra Costa County, CA, Monterey County, CA, San Benito County, CA, San Mateo County, CA, Santa Clara County, CA, Santa Cruz County, CA
The radar
The San Francisco radar (KMUX), 12 km from the middle of the area, began a volume at 21:23 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, 9.4 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
- 1 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 714 m above ground
- 0-6 km bulk shear
- 40 kt
- 0-1 km storm-relative helicity
- 5 m²/s²
- 0-3 km storm-relative helicity
- 68 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
136 WWUS86 KMTR 072121 RFWMTR URGENT - FIRE WEATHER MESSAGE National Weather Service San Francisco Bay Area 221 PM PDT Thu Oct 7 2021 ...Fire Weather Watch for Monday afternoon into Tuesday evening for gusty north winds along the eastern interior areas of the North Bay mountains, East Bay hills, and East Bay valleys... The next weather system will impact the area early next week. Moderate to high confidence in stronger north winds and drier air early next week behind a passing cold front. The eastern interior areas of the North Bay mountains, East Bay hills, and East Bay valleys have the highest confidence in seeing gusty north winds. The window for strongest winds will be from Monday morning through Tuesday evening. These winds, in conjunction with little to no recent precipitation and near to record dry fuels across the interior, may lead to an increased risk of critical fire weather concerns for the specified locations. CAZ507-510-511-080530- /O.NEW.KMTR.FW.A.0007.211011T1800Z-211013T0000Z/ North Bay Mountains-East Bay Interior Valleys- East Bay Hills and the Diablo Range- 221 PM PDT Thu Oct 7 2021 ...FIRE WEATHER WATCH IN EFFECT FROM MONDAY MORNING THROUGH TUESDAY AFTERNOON FOR GUSTY NORTH WINDS AND LOW HUMIDITY FOR INTERIOR NORTH AND EAST BAY HILLS AS WELL AS THE INTERIOR EAST BAY VALLEYS... THE NATIONAL WEATHER SERVICE IN San Francisco has issued a Fire Weather Watch for gusty north winds and dry conditions which is in effect from Monday morning through Tuesday afternoon. * AFFECTED AREA...North Bay Mountains as well as East Bay hills and valleys. The area of highest concern are the interior portions of the North Bay Mountains and East Bay hills and valleys. Lower concern for coastal ranges that should see more northwest winds, which will bring in higher humidities. * WIND...North to Northeast 15 to 25 mph with gusts 30 to 40 mph. Strongest winds are expected along the eastern areas of Napa, Contra Costa, and Alameda counties. * HUMIDITY...Overnight recoveries 20-50%. Minimum daytime humidities 10-20%. * IMPACTS...Any fire starts would likely see rapid spread due to dry fuels, low humidity and gusty winds. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Fire Weather Watch means that critical fire weather conditions are forecast to occur. Listen for later forecasts and possible Red Flag Warnings. && $$ ED
7 follow-up statements
347 WWUS86 KMTR 080441 RFWMTR URGENT - FIRE WEATHER MESSAGE National Weather Service San Francisco CA 941 PM PDT Thu Oct 7 2021 ...Fire Weather Watch issued for Monday afternoon into Tuesday evening for gusty northerly winds along the eastern interior areas of the North Bay mountains, East Bay hills, and East Bay valleys... The next weather system will impact the area early next week. Moderate to high confidence in stronger northerly winds and drier air early next week behind a passing cold front. The eastern interior areas of the North Bay mountains, East Bay hills, and East Bay valleys have the highest confidence in seeing gusty northerly winds. The window for strongest winds will be from Monday morning through Tuesday evening. These winds, in conjunction with little to no recent precipitation and near to record dry fuels across the interior, may lead to an increased risk of critical fire weather concerns for the specified locations. CAZ507-510-511-081300- /O.CON.KMTR.FW.A.0007.211011T1800Z-211013T0000Z/ North Bay Mountains-East Bay Interior Valleys- East Bay Hills and the Diablo Range- 941 PM PDT Thu Oct 7 2021 ...FIRE WEATHER WATCH REMAINS IN EFFECT FROM MONDAY MORNING THROUGH TUESDAY AFTERNOON FOR GUSTY NORTHERLY WINDS AND LOW HUMIDITY FOR INTERIOR NORTH BAY MOUNTAINS AND EAST BAY HILLS AS WELL AS THE INTERIOR EAST BAY VALLEYS... * AFFECTED AREA...North Bay Mountains as well as East Bay hills and valleys. The areas of highest concern are the interior portions of the North Bay Mountains and East Bay hills and valleys. Lower concern for coastal ranges that should see more northwest winds, which will bring in higher humidities. * WIND...North to Northeast 15 to 25 mph with gusts 30 to 40 mph, locally higher. Strongest winds are expected along the eastern areas of Napa, Contra Costa, and Alameda counties. * HUMIDITY...Overnight recoveries 20-50%. Minimum daytime humidities 10-20%. * IMPACTS...Any fire starts would likely see rapid spread due to dry fuels, low humidity and gusty winds. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Fire Weather Watch means that critical fire weather conditions are forecast to occur. Listen for later forecasts and possible Red Flag Warnings. && $$
481 WWUS86 KMTR 081140 RFWMTR URGENT - FIRE WEATHER MESSAGE National Weather Service San Francisco CA 440 AM PDT Fri Oct 8 2021 ...Gusty northerly winds and dry conditions late Monday morning through late Tuesday afternoon for the interior areas of the North Bay mountains, the East Bay hills, and the East Bay valleys... .On Monday, a strong inside slider type of weather system will move southward through the Great Basin. North winds are forecast to rapidly ramp up behind it, especially over more interior portions of the North and East Bay. These winds, combined with low humidities and dry fuels, may result in critical fire weather conditions. CAZ507-510-511-082300- /O.CON.KMTR.FW.A.0007.211011T1800Z-211013T0000Z/ North Bay Mountains-East Bay Interior Valleys- East Bay Hills and the Diablo Range- 440 AM PDT Fri Oct 8 2021 ...Fire Weather Watch remains in effect for late Monday morning through late Tuesday afternoon for the interior North Bay mountains, East Bay hills, and East Bay valleys... * AFFECTED AREA...North Bay Mountains as well as East Bay hills and valleys. The areas of highest concern are the interior portions of the North Bay Mountains and East Bay hills and valleys. Lower concern for coastal ranges that should see more northwest winds, which will bring in higher humidities. * WIND...North to Northeast 15 to 25 mph with gusts 30 to 40 mph, locally higher. Strongest winds are expected along the eastern areas of Napa, Contra Costa, and Alameda counties. * HUMIDITY...Overnight recoveries 20-50%. Minimum daytime humidities 10-20%. * IMPACTS...Any fire starts would likely see rapid spread due to dry fuels, low humidity and gusty winds. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Fire Weather Watch means that critical fire weather conditions are forecast to occur. Listen for later forecasts and possible Red Flag Warnings. && $$
641 WWUS86 KMTR 081645 RFWMTR URGENT - FIRE WEATHER MESSAGE National Weather Service San Francisco CA 945 AM PDT Fri Oct 8 2021 ...Gusty northerly winds and dry conditions late Sunday evening through late Tuesday afternoon for the interior areas of the North Bay mountains, the East Bay hills, and the East Bay valleys... .A strong inside slider will move southward through the Great Basin late Sunday into Monday, with increasing offshore gradients expected. North winds will quickly increase late Sunday night, especially over more interior portions of the North and East Bay. These winds, combined with low humidities and dry fuels, may result in critical fire weather conditions. CAZ507-510-511-090045- /O.EXT.KMTR.FW.A.0007.211011T0600Z-211013T0000Z/ North Bay Mountains-East Bay Interior Valleys- East Bay Hills and the Diablo Range- 945 AM PDT Fri Oct 8 2021 ...FIRE WEATHER WATCH NOW IN EFFECT FROM SUNDAY EVENING THROUGH TUESDAY AFTERNOON FOR GUSTY NORTHERLY WINDS AND LOW HUMIDITY FOR THE INTERIOR NORTH BAY MOUNTAINS, EAST BAY HILLS, AND THE EAST BAY VALLEYS... * AFFECTED AREA...Fire Weather Zone 507 North Bay Mountains, Fire Weather Zone 510 East Bay Interior Valleys and Fire Weather Zone 511 East Bay Hills and the Diablo Range. * WIND...North to Northeast 15 to 25 mph with gusts 30 to 40 mph, locally higher gusts 50 mph to 60 mph. Strongest winds are expected along the eastern areas of Napa, Contra Costa, and Alameda counties. * HUMIDITY...Overnight recoveries 20-40%. Minimum daytime humidities 10-20%. * IMPACTS...Any fire starts would likely see rapid spread due to dry fuels, low humidity and gusty winds. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Fire Weather Watch means that critical fire weather conditions are forecast to occur. Listen for later forecasts and possible Red Flag Warnings. && $$ Palmer
261 WWUS86 KMTR 090025 RFWMTR URGENT - FIRE WEATHER MESSAGE National Weather Service San Francisco CA 525 PM PDT Fri Oct 8 2021 ...Gusty northerly winds and dry conditions late Sunday evening through late Tuesday afternoon for the interior areas of the North Bay mountains, the East Bay hills, and the East Bay valleys... .A strong inside slider will move southward through the Great Basin late Sunday into Monday, with increasing offshore gradients expected. North winds will quickly increase late Sunday night, especially over more interior portions of the North and East Bay. These winds, combined with low humidities and dry fuels, may result in critical fire weather conditions. CAZ507-510-511-091200- /O.CON.KMTR.FW.A.0007.211011T0600Z-211013T0000Z/ North Bay Mountains-East Bay Interior Valleys- East Bay Hills and the Diablo Range- 525 PM PDT Fri Oct 8 2021 ...FIRE WEATHER WATCH NOW IN EFFECT FROM SUNDAY EVENING THROUGH TUESDAY AFTERNOON FOR GUSTY NORTHERLY WINDS AND LOW HUMIDITY FOR THE INTERIOR NORTH BAY MOUNTAINS, EAST BAY HILLS, AND THE EAST BAY VALLEYS... * AFFECTED AREA...Fire Weather Zone 507 North Bay Mountains, Fire Weather Zone 510 East Bay Interior Valleys and Fire Weather Zone 511 East Bay Hills and the Diablo Range. * WIND...North to Northeast 15 to 25 mph with gusts 30 to 40 mph, locally higher gusts 50 mph to 60 mph. Strongest winds are expected along the eastern areas of Napa, Contra Costa, and Alameda counties. * HUMIDITY...Overnight recoveries 20-40%. Minimum daytime humidities 10-20%. * IMPACTS...Any fire starts would likely see rapid spread due to dry fuels, low humidity and gusty winds. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Fire Weather Watch means that critical fire weather conditions are forecast to occur. Listen for later forecasts and possible Red Flag Warnings. && $$
526 WWUS86 KMTR 091133 RFWMTR URGENT - FIRE WEATHER MESSAGE National Weather Service San Francisco CA 433 AM PDT Sat Oct 9 2021 ...Gusty northerly winds and dry conditions late Sunday evening through late Tuesday afternoon for the interior areas of the North Bay mountains, the East Bay hills, and the East Bay valleys... .A strong inside slider will move southward through the Great Basin late Sunday into Monday, with increasing offshore gradients expected. North winds will quickly increase late Sunday night, especially over more interior portions of the North and East Bay. These winds, combined with low humidities and dry fuels, may result in critical fire weather conditions. CAZ507-510-511-091945- /O.CON.KMTR.FW.A.0007.211011T0600Z-211013T0000Z/ North Bay Mountains-East Bay Interior Valleys- East Bay Hills and the Diablo Range- 433 AM PDT Sat Oct 9 2021 ...FIRE WEATHER WATCH REMAINS IN EFFECT FROM SUNDAY EVENING THROUGH TUESDAY AFTERNOON FOR GUSTY NORTHERLY WINDS FOR THE INTERIOR NORTH BAY MOUNTAINS, EAST BAY HILLS, AND THE EAST BAY VALLEYS... * AFFECTED AREA...Fire Weather Zone 507 North Bay Mountains, Fire Weather Zone 510 East Bay Interior Valleys and Fire Weather Zone 511 East Bay Hills and the Diablo Range. * WIND...North to Northeast 15 to 25 mph with gusts 30 to 40 mph, locally higher gusts 50 mph to 60 mph. Strongest winds are expected along the eastern areas of Napa, Contra Costa, and Alameda counties. * HUMIDITY...Overnight recoveries 20-40%. Minimum daytime humidities 10-20%. * IMPACTS...Any fire starts would likely see rapid spread due to dry fuels, low humidity and gusty winds. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Fire Weather Watch means that critical fire weather conditions are forecast to occur. Listen for later forecasts and possible Red Flag Warnings. && $$
042 WWUS86 KMTR 091950 RFWMTR URGENT - FIRE WEATHER MESSAGE National Weather Service San Francisco CA 1250 PM PDT Sat Oct 9 2021 ...Gusty northerly winds and dry conditions late Sunday evening through late Tuesday afternoon for the interior areas of the North Bay mountains, the East Bay hills, and the East Bay valleys... ...Gusty northerly winds and dry conditions early Monday morning through late Tuesday afternoon for the Santa Cruz Mountains... ...Gusty northerly winds and dry conditions Monday morning through late Tuesday afternoon for the Mountains of San Benito and interior Monterey County, and the Santa Lucia Mountains... .A strong inside slider will move southward through the Great Basin late Sunday into Monday, with increasing offshore gradients expected. North winds will quickly increase late Sunday night, especially over more interior portions of the North and East Bay, before spread into the Santa Cruz Mountains as well as the Mountains of San Benito and interior Monterey County, the Santa Lucia Mountains, and the Los Padres National Forest. These winds, combined with low humidity and dry fuels, may result in critical fire weather conditions. CAZ512-101200- /O.EXB.KMTR.FW.A.0007.211011T0900Z-211013T0000Z/ Santa Cruz Mountains- 1250 PM PDT Sat Oct 9 2021 ...FIRE WEATHER WATCH IN EFFECT FROM LATE SUNDAY NIGHT THROUGH TUESDAY AFTERNOON FOR GUSTY NORTH WINDS AND LOW HUMIDITY FOR THE SANTA CRUZ MOUNTAINS... The National Weather Service in San Francisco has issued a Fire Weather Watch for gusty north to northeast winds and low humidity, which is in effect from late Sunday night through Tuesday afternoon. * AFFECTED AREA...Fire Weather Zone 512 Santa Cruz Mountains. * WIND...North to Northeast 15 to 30 mph with gusts 40 to 50 mph, locally higher gusts up to 60 mph. * HUMIDITY...Overnight recoveries 20-40%. Minimum daytime humidities 10-20%. * IMPACTS...Any fire starts would likely see rapid spread due to dry fuels, low humidity and gusty winds. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Fire Weather Watch means that critical fire weather conditions are forecast to occur. Listen for later forecasts and possible Red Flag Warnings. && $$ CAZ517-518-101200- /O.EXB.KMTR.FW.A.0007.211011T1200Z-211013T0000Z/ Santa Lucia Mountains and Los Padres National Forest- Mountains Of San Benito County And Interior Monterey County Including Pinnacles National Park- 1250 PM PDT Sat Oct 9 2021 ...FIRE WEATHER WATCH IN EFFECT FROM LATE SUNDAY NIGHT THROUGH TUESDAY AFTERNOON FOR GUSTY NORTH TO NORTHEAST WINDS AND LOW HUMIDITY FOR THE MOUNTAINS OF SAN BENITO COUNTY AND INTERIOR MONTEREY COUNTY INCLUDING PINNACLES NATIONAL PARK AS WELL AS THE SANTA LUCIA MOUNTAINS AND THE LOS PADRES NATIONAL FOREST... The National Weather Service in San Francisco has issued a Fire Weather Watch for gusty north to northeast wind and low humidity, which is in effect from late Sunday night through Tuesday afternoon. * AFFECTED AREA...Fire Weather Zone 517 Santa Lucia Mountains and Los Padres National Forest and Fire Weather Zone 518 Mountains Of San Benito County And Interior Monterey County Including Pinnacles National Park. * WIND...North to Northeast 15 to 30 mph with gusts 40 to 50 mph, locally higher gusts up to 60 mph. * HUMIDITY...Overnight recoveries 20-40%. Minimum daytime humidities 10-20%. * IMPACTS...Any fire starts would likely see rapid spread due to dry fuels, low humidity and gusty winds. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Fire Weather Watch means that critical fire weather conditions are forecast to occur. Listen for later forecasts and possible Red Flag Warnings. && $$ CAZ507-510-511-101200- /O.CON.KMTR.FW.A.0007.211011T0600Z-211013T0000Z/ North Bay Mountains-East Bay Interior Valleys- East Bay Hills and the Diablo Range- 1250 PM PDT Sat Oct 9 2021 ...FIRE WEATHER WATCH REMAINS IN EFFECT FROM SUNDAY EVENING THROUGH TUESDAY AFTERNOON FOR GUSTY NORTH TO NORTHEAST WINDS AND LOW HUMIDITY FOR THE INTERIOR NORTH BAY MOUNTAINS, EAST BAY HILLS, AND THE EAST BAY VALLEYS... * AFFECTED AREA...Fire Weather Zone 507 North Bay Mountains, Fire Weather Zone 510 East Bay Interior Valleys and Fire Weather Zone 511 East Bay Hills and the Diablo Range. * WIND...North to Northeast 15 to 25 mph with gusts 35 to 45 mph, locally higher gusts up to 60 mph. Strongest winds are expected along the eastern areas of Napa, Contra Costa, and Alameda counties. * HUMIDITY...Overnight recoveries 20-40%. Minimum daytime humidities 10-20%. * IMPACTS...Any fire starts would likely see rapid spread due to dry fuels, low humidity and gusty winds. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Fire Weather Watch means that critical fire weather conditions are forecast to occur. Listen for later forecasts and possible Red Flag Warnings. && $$ Palmer
166 WWUS86 KMTR 101003 RFWMTR URGENT - FIRE WEATHER MESSAGE National Weather Service San Francisco CA 303 AM PDT Sun Oct 10 2021 ...Gusty northerly winds and dry conditions late Sunday evening through late Tuesday afternoon for the interior areas of the North Bay mountains, the East Bay hills, and the East Bay valleys... ...Gusty northerly winds and dry conditions early Monday morning through late Tuesday afternoon for the Santa Cruz Mountains... ...Gusty northerly winds and dry conditions Monday morning through late Tuesday afternoon for the Mountains of San Benito and interior Monterey County, and the Santa Lucia Mountains... .A strong inside slider will move southward through the Great Basin late Sunday into Monday, with increasing offshore gradients expected. North winds will quickly increase late Sunday night, especially over more interior portions of the North and East Bay, before spreading into the Santa Cruz Mountains as well as the Mountains of San Benito and interior Monterey County, the Santa Lucia Mountains, and the Los Padres National Forest. The gradient becomes north to northeast Monday night into Tuesday. These winds, combined with low humidity and dry fuels, may result in critical fire weather conditions. CAZ507-510-511-101815- /O.UPG.KMTR.FW.A.0007.211011T0600Z-211013T0000Z/ /O.NEW.KMTR.FW.W.0008.211011T0600Z-211013T0000Z/ North Bay Mountains-East Bay Interior Valleys- East Bay Hills and the Diablo Range- 303 AM PDT Sun Oct 10 2021 ...RED FLAG WARNING IN EFFECT FROM 11 PM THIS EVENING TO 5 PM PDT TUESDAY FOR GUSTY NORTH TO NORTHEAST WINDS AND LOW HUMIDITY FOR THE INTERIOR NORTH BAY MOUNTAINS, EAST BAY HILLS, AND THE EAST BAY VALLEYS... The National Weather Service in San Francisco has issued a Red Flag Warning for gusty north to northeast winds and low humidity, which is in effect from 11 PM this evening to 5 PM PDT Tuesday. The Fire Weather Watch is no longer in effect. * AFFECTED AREA...Fire Weather Zone 507 North Bay Mountains, Fire Weather Zone 510 East Bay Interior Valleys and Fire Weather Zone 511 East Bay Hills and the Diablo Range. * TIMING...Sunday night into Tuesday. Strong winds will be more widespread during the day Monday. * WINDS...North to Northeast 15 to 25 mph with gusts 35 to 45 mph, locally higher gusts up to 60 mph. Strongest winds are expected along the eastern areas of Napa, Contra Costa, and Alameda counties. * HUMIDITY...Minimum day time humidities 10-20 percent. Overnight recoveries 20-40 percent for the interior mountains of Sonoma County, Napa County, and East Bay, but higher recoveries of 50-65 percent for coastal mountains. * IMPACTS...Any fire starts would likely see rapid spread due to dry fuels, low humidity and gusty winds. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now...or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ CAZ512-101815- /O.UPG.KMTR.FW.A.0007.211011T0900Z-211013T0000Z/ /O.NEW.KMTR.FW.W.0008.211011T0900Z-211013T0000Z/ Santa Cruz Mountains- 303 AM PDT Sun Oct 10 2021 ...RED FLAG WARNING IN EFFECT FROM 2 AM MONDAY TO 5 PM PDT TUESDAY FOR GUSTY NORTH WINDS AND LOW HUMIDITY FOR THE SANTA CRUZ MOUNTAINS... The National Weather Service in San Francisco has issued a Red Flag Warning for gusty north to northeast winds, which is in effect from 2 AM Monday to 5 PM PDT Tuesday. The Fire Weather Watch is no longer in effect. * AFFECTED AREA...Fire Weather Zone 512 Santa Cruz Mountains. * WINDS...North 15 to 30 mph with gusts 40 to 50 mph. Locally higher gusts up to 60 mph are possible over peaks. * HUMIDITY...15-25 percent except up to 40 percent closer to the coast. Overnight recoveries 30-50 percent. * IMPACTS...Any fire starts would likely see rapid spread due to dry fuels, low humidity and gusty winds. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now...or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ CAZ517-518-101815- /O.UPG.KMTR.FW.A.0007.211011T1200Z-211013T0000Z/ /O.NEW.KMTR.FW.W.0008.211011T1200Z-211013T0000Z/ Santa Lucia Mountains and Los Padres National Forest- Mountains Of San Benito County And Interior Monterey County Including Pinnacles National Park- 303 AM PDT Sun Oct 10 2021 ...RED FLAG WARNING IN EFFECT FROM 5 AM MONDAY TO 5 PM PDT TUESDAY FOR GUSTY NORTH TO NORTHEAST WINDS AND LOW HUMIDITY FOR THE MOUNTAINS OF SAN BENITO COUNTY AND INTERIOR MONTEREY COUNTY INCLUDING PINNACLES NATIONAL PARK AS WELL AS THE SANTA LUCIA MOUNTAINS AND THE LOS PADRES NATIONAL FOREST... The National Weather Service in San Francisco has issued a Red Flag Warning for gusty north to northeast winds and low humidity, which is in effect from 5 AM Monday to 5 PM PDT Tuesday. The Fire Weather Watch is no longer in effect. * AFFECTED AREA...Fire Weather Zone 517 Santa Lucia Mountains and Los Padres National Forest and Fire Weather Zone 518 Mountains Of San Benito County And Interior Monterey County Including Pinnacles National Park. * WIND...North to Northeast 15 to 30 mph with gusts 40 to 50 mph. * HUMIDITY...Overnight recoveries 20-40%. Minimum daytime humidities 10-20%. * IMPACTS...Any fire starts would likely see rapid spread due to dry fuels, low humidity and gusty winds. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now...or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ Bingaman
What forecasters said that day
The local office's own words before this fire weather watch 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 fire weather watch went out at Oct 7, 11:03 AM PDT, 3 hours 18 minutes earlier.
Area forecast discussion, Oct 7, 11:03 AM PDT, 3 hours 18 minutes before
Area Forecast Discussion
National Weather Service San Francisco Bay Area
1103 AM PDT Thu Oct 7 2021
.SYNOPSIS...Passing high clouds and continued unseasonably cool,
especially inland today. A weak low pushes onshore tonight into
early Friday and may generate a few light showers over the South
Bay and Central Coast. Otherwise continued dry and seasonably cool
on Friday. A final system passes offshore Friday night into early
Saturday and could skirt the coast with a few light showers. High
pressure rebuilds this weekend with seasonably mild and dry
weather. A system dropping into the Great Basin early next week
may produce periods of gusty north winds Monday into Tuesday that
may increase fire weather concerns.
&&
.DISCUSSION...as of 3:29 AM PDT Thursday...Mostly cloudy skies
this morning with a mix of low and high level clouds as
temperatures remain cool. The marine layer is mixed out with cool
air aloft wiping out the inversion layer. Inland areas will run
about 5-10 degrees below normal again today with highs generally
in the upper 60s to lower 70s as skies remain partly to mostly
cloudy. An upper low will move inland tonight and there is about a
20 percent chance of some light rain showers, mainly focused over
the Central Coast but also into the hills of Santa Clara county
and the far East Bay. Any precip looks to be showery and light
with most locations seeing no precip from this system.
No big changes in the weather for Friday as temps remain on the
cool side of normal. Expect another day of highs mainly in the 60s
across the region. One notable change in the forecast is a final
shortwave that will drop down over the ocean Friday night. The
shorter term NAM as well as global models have started to pick up
on this over the last few model runs as the main upper trough lags
slightly slower than previous runs. Forecast will now show about
a 20 percent of showers Friday night into the pre-dawn hours of
Saturday but mainly over the ocean waters. However would not be
surprised to get some reports of light rain or sprinkles for
coastal locations from Sonoma county southward to the Santa Cruz
mountains, especially if the system takes a near shore track. So
some folks may wake up to some wet pavement on Saturday morning.
However at this time do not expect any shower activity in the City
on Friday night or Saturday.
High pressure then builds this weekend with a return to slightly
warmer temps back into the upper 60s and 70s with more sunshine
and minimal marine layer influence. In general an ideal weekend
for outdoor activity with no unusually hot or adverse weather.
Forecast focus then turns to potentially impactful weather early
next week. A stronger system is currently forecast to drop into
the Great Basin late Sunday night into Monday morning. On the
backside of this low moderate to strong northerly winds would
develop across the region. Main concerns for this time of year
will be fire weather related though it does not look to be an
archetype offshore wind event, there are still disconcerting
signals that will bear close watching. Time frame is still far
enough out that a lot of details could change and the exact trough
location will be important for how the pattern develops. Latest
SPC fire weather probabilities are at 40 percent for critical
conditions developing later Monday into Tuesday.
This setup will not be associated with warm weather but model data
shows RH values rapidly drying out during the day Monday into
Tuesday. We are not expecting much precip between now and then so
even though fine fuels will be moderated slightly the fuels remain
drought stressed with critically low live fuel moisture values.
Looking at the ECMWF extreme forecast index we see strong signals
for abnormally strong northerly winds. Given the potentially
strong cold advection across the Great Basin, strong surface
pressure gradient and upper level support there is the potential
for strong winds in places that aren't usually windy under normal
offshore wind patterns. All this to say is we will be watching the
pattern and setup closely as we enter the climatological peak of
our fire season across the greater Bay Area.
Longer range trends now suggest a more benign weather pattern
Weds through Friday of next week.
&&
.AVIATION...as of 11:04 AM PDT Thursday...For the 18z TAFs. High
clouds continue to move through the region. Increasing winds this
afternoon will help dissipate lingering low clouds. These more
moderate winds look to last until nightfall. Higher clouds will
last through the TAF period but mid clouds (4000 to 6000 ft AGL)
look to affect the region tonight and lasting into tomorrow
morning. Expect MVFR and chances for drizzle around the Monterey
Bay in the late night and lingering into Friday morning. The early
morning to mid looks to provide moments of MVFR around the SF Bay
as well. Expect mid and high clouds to last into Friday with
breezy conditions expected that afternoon.
Vicinity of KSFO... VFR with lingering high clouds. Expect Westerly
winds to increase to around 15 in the mid afternoon. These winds
look to last into the night and become lighter, but still moderate
for the late night. Low clouds will struggle to filter into the SF
Bay Friday morning, but look to offer moments of MVFR until the mid
morning. Afterwards, expect a breezy to gusty afternoon with VFR for
Friday.
KSFO Bridge Approach...Similar to KSFO.
Monterey Bay... VFR until the late night with high clouds
continuing. Expect moderate winds this afternoon, which will back
off into the evening. Mid-level clouds will move through in the late
night with some areas seeing MVFR overnight as low clouds also
build. Chances for light drizzle will be possible in the late night
and look to linger into the early morning.
&&
.MARINE...as of 11:02 AM PDT Thursday...Winds out of the northwest
remain breezy to moderately gusty but will decrease further into
the day. Waves will stay wind driven and are resulting in squared
seas, where the wave height is similar to the period, from 8 to
11 feet at 10 to 11 seconds. These squared seas are generating
steep wind waves making hazardous conditions, particularly for
smaller vessels. Light to moderate winds are expected at the
start of the weekend with a weak boundary passing over the waters
providing a slight chance for light showers Saturday morning. The
next front with strong wind gusts is forecast to approach the
coastal waters on Sunday night into early next week.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.Tday...SCA...Pt Arena to Pt Reyes 0-10 nm
SCA...Pt Reyes to Pigeon Pt 0-10 nm
SCA...Pigeon Pt to Pt Pinos 0-10 nm
SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm
SCA...Pt Arena to Pigeon Pt 10-60 nm
SCA...Pigeon Pt to Pt Piedras Blancas 10-60 nm until 3 PM
SCA...Mry Bay from 3 PM
&&
PUBLIC FORECAST: RWW
AVIATION: Murdock
MARINE: Murdock
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www.youtube.com/nwsbayareaThe office that day
Everything else NWS San Francisco Bay Area, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 7, 2:45 AM PDT | Small Craft Advisory | MTR | 42 hr | |
| Oct 7, 2:27 PM PDT | Small Craft Advisory | MTR | 37 hr |
Nearby
Fire Weather Watches in California, 2021Every fire weather watch in 2021
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.