Red Flag Warning 4, NWS San Francisco Bay Area, CA

757 
WWUS86 KMTR 082122
RFWMTR

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Francisco CA
222 PM PDT Tue Oct 8 2019

...RED FLAG WARNING IN EFFECT FOR THE NORTH AND EAST BAY HILLS
AND VALLEYS FROM 5 AM WEDNESDAY THROUGH 5 PM PDT THURSDAY...

...RED FLAG WARNING IN EFFECT FOR THE SANTA CRUZ MOUNTAINS FROM
5 PM WEDNESDAY THROUGH NOON PDT THURSDAY...

.A low pressure trough is forecast to drop into the Great Basin
late tonight and Wednesday. This will create conditions favorable
for strong and gusty northerly winds across much of the North Bay
and East Bay as well as the Santa Cruz Mountains. In addition, a
very dry airmass will sweep across the region by late Wednesday.
Daytime minimum humidity values are expected to drop into the
teens on Wednesday, and possibly to the single digits by
Thursday. Nighttime humidity recoveries will be very poor,
especially on Wednesday night. The combination of strong and
gusty offshore winds, very low humidity, and dry fuels will
create critical fire weather conditions.

CAZ507-511-091200-
/O.CON.KMTR.FW.W.0004.191009T1200Z-191011T0000Z/
North Bay Mountains-East Bay Hills and the Diablo Range-
222 PM PDT Tue Oct 8 2019

...RED FLAG WARNING REMAINS IN EFFECT FROM 5 AM WEDNESDAY TO 5 PM
PDT THURSDAY FOR STRONG OFFSHORE WINDS AND LOW HUMIDITY FOR FIRE 
WEATHER ZONES 507 AND 511...

* AFFECTED AREA...Fire weather zones 507 and 511...The North Bay
  Mountains...The East Bay Hills and the Diablo Range.

* WIND...North to northeast winds of 20 to 30 mph with gusts of 45
  to 55 mph. Locally higher gusts to 65 mph are likely across
  higher ridges and peaks of Sonoma and Napa on Wednesday Night.

* HUMIDITY...Daytime minimum relative humidity in the teens and 
  as low as the single digits by Thursday. Very poor overnight 
  humidity recoveries...only to 20 to 30 percent Wednesday 
  night. 

* HIGHEST THREAT...All portions of the North and East Bay Hills
  will likely experience critical fire weather conditions. The
  time period of greatest concern is late Wednesday afternoon 
  through early Thursday.

* IMPACTS...Any fires that develop will likely spread rapidly. 

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.

&&

$$

CAZ506-510-091200-
/O.CON.KMTR.FW.W.0004.191009T1200Z-191011T0000Z/
North Bay Interior Valleys-East Bay Interior Valleys-
222 PM PDT Tue Oct 8 2019

...RED FLAG WARNING REMAINS IN EFFECT FROM 5 AM WEDNESDAY TO 5 PM
PDT THURSDAY FOR GUSTY OFFSHORE WINDS AND LOW HUMIDITY FOR FIRE 
WEATHER ZONES 506 AND 510...

* AFFECTED AREA...Fire weather zones 506 and 510...The North Bay
  Interior Valleys...The East Bay Interior Valleys.

* WIND...North to northeast winds of 10 to 20 mph with gusts up to
  40 mph. 

* HUMIDITY...Daytime minimum relative humidity in the teens and 
  as low as the single digits by Thursday. Very poor overnight 
  humidity recoveries...only to 25 to 35 percent Wednesday 
  night. 

* HIGHEST THREAT...Eastern side of the valleys. The time period
  of greatest concern is Wednesday night. 

* IMPACTS...Any fires that develop will likely spread rapidly. 
 
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.

&&

$$

CAZ512-091200-
/O.CON.KMTR.FW.W.0004.191010T0000Z-191010T1900Z/
Santa Cruz Mountains-
222 PM PDT Tue Oct 8 2019

...RED FLAG WARNING REMAINS IN EFFECT FROM 5 PM WEDNESDAY TO NOON
PDT THURSDAY FOR GUSTY OFFSHORE WINDS AND LOW HUMIDITY FOR FIRE 
WEATHER ZONE 512...

* AFFECTED AREA...Fire weather zone 512...The Santa Cruz Mountains.

* WIND...North to northeast winds of 15 to 25 mph with gusts of
  35 to 45 mph. 

* HUMIDITY...Daytime minimum relative humidity in the teens and 
  as low as the single digits by Thursday. Very poor overnight 
  humidity recoveries...only to 20 to 30 percent Wednesday 
  night. 

* HIGHEST THREAT...Highest ridges and peaks as well as 
  southwest-facing slopes. The time period of greatest concern 
  is Wednesday night.

* IMPACTS...Any fires that develop will likely spread rapidly.

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.

&&

$$

416 
WWUS86 KMTR 091159
RFWMTR

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Francisco CA
459 AM PDT Wed Oct 9 2019

...RED FLAG WARNING IN EFFECT FOR THE NORTH AND EAST BAY HILLS
AND VALLEYS THROUGH 5 PM PDT THURSDAY...

...RED FLAG WARNING IN EFFECT FOR THE SANTA CRUZ MOUNTAINS FROM
5 PM WEDNESDAY THROUGH NOON PDT THURSDAY...

.Strong and gusty northerly winds will develop across much of the
North Bay and East Bay as well as the Santa Cruz Mountains today
and tonight. Strongest winds are expected from this evening
through early Thursday, when gusts of 45 to 65 mph are forecast
across the ridges. In addition, a very dry airmass will sweep 
across the region today. Daytime minimum humidity values are 
expected to drop into the single digits today and remain very low 
into Thursday. Nighttime humidity recoveries will be very poor 
tonight. The combination of strong and gusty offshore winds, very 
low humidity, and dry fuels will create critical fire weather 
conditions today through Thursday.

CAZ507-511-100000-
/O.CON.KMTR.FW.W.0004.191009T1200Z-191011T0000Z/
North Bay Mountains-East Bay Hills and the Diablo Range-
459 AM PDT Wed Oct 9 2019

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 5 PM PDT THURSDAY FOR
STRONG OFFSHORE WINDS AND LOW HUMIDITY FOR FIRE WEATHER ZONES
507 AND 511...

* AFFECTED AREA...Fire weather zones 507 and 511...The North Bay 
  Mountains...The East Bay Hills and the Diablo Range. 

* WIND...North to northeast winds of 20 to 30 mph with gusts of
  45 to 55 mph. Locally higher gusts to 65 mph are likely 
  across higher ridges and peaks of Sonoma and Napa Counties on 
  Wednesday Night. 

* HUMIDITY...Daytime minimum relative humidity in the single
  digits today and Thursday. Very poor overnight humidity
  recoveries...only to 15 to 25 percent tonight. 

* HIGHEST THREAT...All portions of the North and East Bay Hills 
  will likely experience critical fire weather conditions. The 
  time period of greatest concern is late Wednesday afternoon 
  through early Thursday.

* IMPACTS...Any fires that develop will likely spread rapidly.

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.

&&

$$

CAZ506-510-100000-
/O.CON.KMTR.FW.W.0004.191009T1200Z-191011T0000Z/
North Bay Interior Valleys-East Bay Interior Valleys-
459 AM PDT Wed Oct 9 2019

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 5 PM PDT THURSDAY FOR
GUSTY OFFSHORE WINDS AND LOW HUMIDITY FOR FIRE WEATHER ZONES
506 AND 510...

* AFFECTED AREA...Fire weather zones 506 and 510...The North Bay 
  Interior Valleys...The East Bay Interior Valleys. 

* WIND...North to northeast winds of 10 to 20 mph with gusts up
  to 40 mph. 

* HUMIDITY...Daytime minimum relative humidity in the teens and 
  as low as the single digits by Thursday. Very poor overnight 
  humidity recoveries...only to 20 to 30 percent Wednesday 
  night. 

* HIGHEST THREAT...Eastern side of the valleys. The time period 
  of greatest concern is Wednesday night.

* IMPACTS...Any fires that develop will likely spread rapidly.

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.

&&

$$

CAZ512-100000-
/O.CON.KMTR.FW.W.0004.191010T0000Z-191010T1900Z/
Santa Cruz Mountains-
459 AM PDT Wed Oct 9 2019

...RED FLAG WARNING REMAINS IN EFFECT FROM 5 PM THIS AFTERNOON TO
NOON PDT THURSDAY FOR GUSTY OFFSHORE WINDS AND LOW HUMIDITY FOR
FIRE WEATHER ZONE 512...

* AFFECTED AREA...Fire weather zone 512...The Santa Cruz 
  Mountains. 

* WIND...North to northeast winds of 15 to 25 mph with gusts of 
  35 to 45 mph.

* HUMIDITY...Daytime minimum relative humidity in the teens and as
  low as the single digits by Thursday. Very poor overnight
  humidity recoveries...only to 20 to 30 percent tonight. 

* HIGHEST THREAT...Highest ridges and peaks as well as 
  southwest-facing slopes. The time period of greatest concern 
  is Wednesday night.

* IMPACTS...Any fires that develop will likely spread rapidly.

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.

&&

$$

111 
WWUS86 KMTR 092115
RFWMTR

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Francisco CA
215 PM PDT Wed Oct 9 2019

...RED FLAG WARNING IN EFFECT FOR THE NORTH AND EAST BAY HILLS
AND VALLEYS THROUGH 5 PM PDT THURSDAY...

...RED FLAG WARNING IN EFFECT FOR THE SANTA CRUZ MOUNTAINS FROM
5 PM WEDNESDAY THROUGH NOON PDT THURSDAY...

.Strong and gusty northerly winds will develop across the North 
Bay and East Bay as well as the Santa Cruz Mountains tonight. 
Strongest winds are expected from this evening through early 
Thursday, when gusts of 45 to 65 mph are forecast across the 
ridges. In addition, a very dry airmass will sweep across the 
region. Minimum humidity values are expected to drop into the 
single digits and remain very low into Thursday. Nighttime 
humidity recoveries will be very poor tonight. The combination of 
strong and gusty offshore winds, very low humidity, and dry fuels 
will create critical fire weather conditions overnight through 
Thursday.

CAZ507-511-101100-
/O.CON.KMTR.FW.W.0004.000000T0000Z-191011T0000Z/
North Bay Mountains-East Bay Hills and the Diablo Range-
215 PM PDT Wed Oct 9 2019

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 5 PM PDT THURSDAY FOR
STRONG OFFSHORE WINDS AND LOW HUMIDITY FOR FIRE WEATHER ZONES 507
AND 511...

* AFFECTED AREA...Fire weather zones 507 and 511...The North Bay 
  Mountains...The East Bay Hills and the Diablo Range.

* WIND...North to northeast winds of 20 to 30 mph with gusts of 45
  to 55 mph. Locally higher gusts to 65 mph are likely across
  higher ridges and peaks of Sonoma and Napa Counties overnight.

* HUMIDITY...Daytime minimum relative humidity in the single
  digits Thursday. Very poor overnight humidity recoveries...only
  to 15 to 25 percent tonight.

* HIGHEST THREAT...All portions of the North and East Bay Hills
  will likely experience critical fire weather conditions. The
  time period of greatest concern is Wednesday night through 
  early Thursday.

* IMPACTS...Any fires that develop will likely spread rapidly.

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.

&&

$$

CAZ506-510-101100-
/O.CON.KMTR.FW.W.0004.000000T0000Z-191011T0000Z/
North Bay Interior Valleys-East Bay Interior Valleys-
215 PM PDT Wed Oct 9 2019

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 5 PM PDT THURSDAY FOR
GUSTY OFFSHORE WINDS AND LOW HUMIDITY FOR FIRE WEATHER ZONES 506 
AND 510...

* AFFECTED AREA...Fire weather zones 506 and 510...The North Bay 
  Interior Valleys...The East Bay Interior Valleys.

* WIND...North to northeast winds of 10 to 20 mph with gusts up 
  to 40 mph.

* HUMIDITY...Minimum relative humidity in the teens and as low as
  the single digits by Thursday. Very poor overnight humidity 
  recoveries...only to 20 to 30 overnight. 

* HIGHEST THREAT...Eastern side of the valleys. The time period of
  greatest concern is tonight through around sunrise Thursday.

* IMPACTS...Any fires that develop will likely spread rapidly.

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.

&&

$$

CAZ512-101100-
/O.CON.KMTR.FW.W.0004.191010T0000Z-191010T1900Z/
Santa Cruz Mountains-
215 PM PDT Wed Oct 9 2019

...RED FLAG WARNING REMAINS IN EFFECT UNTIL NOON PDT THURSDAY FOR
GUSTY OFFSHORE WINDS AND LOW HUMIDITY FOR FIRE WEATHER ZONE 
512...

* AFFECTED AREA...Fire weather zone 512...The Santa Cruz
  Mountains.

* WIND...North to northeast winds of 15 to 25 mph with gusts of 
  35 to 45 mph.

* HUMIDITY...Minimum relative humidity in the teens and as low as
  the single digits by Thursday. Very poor overnight humidity 
  recoveries...only to 20 to 30 percent tonight.

* HIGHEST THREAT...Highest ridges and peaks as well as southwest-
  facing slopes. The time period of greatest concern is overnight
  through around sunrise Thursday.

* IMPACTS...Any fires that develop will likely spread rapidly.

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.

&&

$$

153 
WWUS86 KMTR 101055
RFWMTR

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Francisco CA
355 AM PDT Thu Oct 10 2019

...RED FLAG WARNING IN EFFECT FOR THE NORTH AND EAST BAY HILLS
AND VALLEYS THROUGH 5 PM PDT THURSDAY...

...RED FLAG WARNING IN EFFECT FOR THE SANTA CRUZ MOUNTAINS FROM
5 PM WEDNESDAY THROUGH NOON PDT THURSDAY...

.Strong and gusty northerly winds will develop across the North
Bay and East Bay as well as the Santa Cruz Mountains through this
morning. Strongest winds are expected through early this morning,
when gusts of 45 to 65 mph are forecast across the ridges. In 
addition, a very dry airmass will sweep across the region. Minimum
humidity values are expected to remain very low through today.  
Nighttime humidity recoveries will continue to be very poor 
tonight. The combination of strong and gusty offshore winds, very 
low humidity, and dry fuels will create critical fire weather 
conditions overnight through today.

CAZ507-511-110000-
/O.CON.KMTR.FW.W.0004.000000T0000Z-191011T0000Z/
North Bay Mountains-East Bay Hills and the Diablo Range-
355 AM PDT Thu Oct 10 2019

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 5 PM PDT THIS
AFTERNOON FOR STRONG OFFSHORE WINDS AND LOW HUMIDITY FOR FIRE
WEATHER ZONES 507 AND 511...

* AFFECTED AREA...Fire weather zones 507 and 511...The North Bay 
  Mountains...The East Bay Hills and the Diablo Range. 

* WIND...North to northeast winds of 20 to 30 mph with gusts of
  45 to 55 mph. Locally higher gusts to 65 mph are likely 
  across higher ridges and peaks of Sonoma and Napa Counties 
  overnight. 

* HUMIDITY...Daytime minimum relative humidity in the single 
  digits Thursday. Very poor overnight humidity recoveries...
  only to 15 to 25 percent tonight.

* HIGHEST THREAT...All portions of the North and East Bay Hills 
  will likely experience critical fire weather conditions. The 
  time period of greatest concern is Wednesday night through 
  early Thursday.

* IMPACTS...Any fires that develop will likely spread rapidly.

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.

&&

$$

CAZ506-510-110000-
/O.CON.KMTR.FW.W.0004.000000T0000Z-191011T0000Z/
North Bay Interior Valleys-East Bay Interior Valleys-
355 AM PDT Thu Oct 10 2019

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 5 PM PDT THIS
AFTERNOON FOR GUSTY OFFSHORE WINDS AND LOW HUMIDITY FOR FIRE
WEATHER ZONES 506 AND 510...

* AFFECTED AREA...Fire weather zones 506 and 510...The North Bay 
  Interior Valleys...The East Bay Interior Valleys. 

* WIND...North to northeast winds of 10 to 20 mph with gusts up 
  to 40 mph.

* HUMIDITY...Minimum relative humidity in the teens and as low 
  as the single digits by Thursday. Very poor overnight humidity 
  recoveries...only to 20 to 30 overnight.

* HIGHEST THREAT...Eastern side of the valleys. The time period
  of greatest concern is tonight through around sunrise 
  Thursday. 

* IMPACTS...Any fires that develop will likely spread rapidly.

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.

&&

$$

CAZ512-101900-
/O.CON.KMTR.FW.W.0004.000000T0000Z-191010T1900Z/
Santa Cruz Mountains-
355 AM PDT Thu Oct 10 2019

...RED FLAG WARNING REMAINS IN EFFECT UNTIL NOON PDT TODAY FOR
GUSTY OFFSHORE WINDS AND LOW HUMIDITY FOR FIRE WEATHER ZONE 512...

* AFFECTED AREA...Fire weather zone 512...The Santa Cruz 
  Mountains. 

* WIND...North to northeast winds of 15 to 25 mph with gusts of 
  35 to 45 mph.

* HUMIDITY...Minimum relative humidity in the teens and as low 
  as the single digits by Thursday. Very poor overnight humidity 
  recoveries...only to 20 to 30 percent tonight.

* HIGHEST THREAT...Highest ridges and peaks as well as 
  southwest-facing slopes. The time period of greatest concern 
  is overnight through around sunrise Thursday. 

* IMPACTS...Any fires that develop will likely spread rapidly.

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.

&&

$$

120 
WWUS86 KMTR 101854
RFWMTR

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Francisco CA
1154 AM PDT Thu Oct 10 2019

...RED FLAG WARNING IN EFFECT FOR THE NORTH AND EAST BAY HILLS
AND VALLEYS THROUGH 5 PM PDT THURSDAY...

.Winds are continuing to ease providing justification to expire
the Red Flag Warning for the Santa Cruz Mountains. With 
continuing offshore winds and dry conditions, the warnings in the
North and East Bays will continue.

CAZ512-102000-
/O.EXP.KMTR.FW.W.0004.000000T0000Z-191010T1900Z/
Santa Cruz Mountains-
1154 AM PDT Thu Oct 10 2019

...RED FLAG WARNING WILL EXPIRE AT NOON PDT TODAY FOR STRONG
OFFSHORE WINDS AND LOW HUMIDITY FOR FIRE WEATHER ZONE 512...

As winds continue to ease in the Santa Cruz mountains, the Red 
Flag Warning will be allowed to expire. Despite the expiration, 
dry conditions and offshore winds will keep the fire danger high.

$$

CAZ507-511-110000-
/O.CON.KMTR.FW.W.0004.000000T0000Z-191011T0000Z/
North Bay Mountains-East Bay Hills and the Diablo Range-
1154 AM PDT Thu Oct 10 2019

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 5 PM PDT THIS
AFTERNOON FOR STRONG OFFSHORE WINDS AND LOW HUMIDITY FOR FIRE 
WEATHER ZONES 507 AND 511...

* AFFECTED AREA...Fire weather zones 507 and 511.

* WIND...North to northeast winds of 20 to 30 mph. Locally higher 
  gusts across higher ridges and peaks of Sonoma and Napa Counties 
  overnight. 

* HUMIDITY...Daytime minimum relative humidity in the single 
  digits Thursday. Poor overnight humidity recoveries tonight.

* HIGHEST THREAT...All portions of the North and East Bay Hills 
  will likely experience critical fire weather conditions.

* IMPACTS...Any fires that develop will likely spread rapidly.

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.

&&

$$

CAZ506-510-110000-
/O.CON.KMTR.FW.W.0004.000000T0000Z-191011T0000Z/
North Bay Interior Valleys-East Bay Interior Valleys-
1154 AM PDT Thu Oct 10 2019

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 5 PM PDT THIS
AFTERNOON FOR STRONG OFFSHORE WINDS AND LOW HUMIDITY FOR FIRE 
WEATHER ZONES 506 AND 510...

* AFFECTED AREA...Fire weather zones 506 and 510.

* WIND...North to northeast winds of 10 to 20 mph.

* HUMIDITY...Minimum relative humidity in the teens and as low 
  as the single digits by Thursday. Very poor overnight 
  humidity recoveries tonight.

* HIGHEST THREAT...Eastern side of the valleys.

* IMPACTS...Any fires that develop will likely spread rapidly.

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.

&&

$$

783 
WWUS86 KMTR 102142
RFWMTR

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Francisco CA
242 PM PDT Thu Oct 10 2019

...RED FLAG WARNING IN EFFECT FOR THE NORTH AND EAST BAY HILLS
AND VALLEYS THROUGH 5 PM PDT THURSDAY...

.Dry offshore winds continue across the Bay Area hills and 
valleys. In addition humidity values remain critically dry in the 
single digits in teens. Red Flag Warning continues through 5 pm 
this afternoon.

CAZ507-511-102345-
/O.CON.KMTR.FW.W.0004.000000T0000Z-191011T0000Z/
North Bay Mountains-East Bay Hills and the Diablo Range-
242 PM PDT Thu Oct 10 2019

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 5 PM PDT THIS
AFTERNOON FOR DRY OFFSHORE WINDS AND LOW HUMIDITY FOR FIRE 
WEATHER ZONES 507 AND 511...

* AFFECTED AREA...Fire weather zones 507 and 511.

* WIND...North to northeast winds of 20 to 30 mph. Locally higher
  gusts to 50 mph across the North and East Bay Hills this 
  afternoon.
 
* HUMIDITY...Daytime minimum relative humidity in the single 
  digits Thursday. Poor overnight humidity recoveries tonight.

* HIGHEST THREAT...All portions of the North and East Bay Hills.

* IMPACTS...Any fires that develop will likely spread rapidly.

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.

&&

$$

CAZ506-510-102345-
/O.CON.KMTR.FW.W.0004.000000T0000Z-191011T0000Z/
North Bay Interior Valleys-East Bay Interior Valleys-
242 PM PDT Thu Oct 10 2019

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 5 PM PDT THIS
AFTERNOON FOR OFFSHORE WINDS AND LOW HUMIDITY FOR FIRE WEATHER 
ZONES 506 AND 510...

* AFFECTED AREA...Fire weather zones 506 and 510.

* WIND...North to northeast winds of 10 to 20 mph gusts to 30 mph.

* HUMIDITY...Minimum relative humidity in the teens and as low as
  the single digits. Very poor overnight humidity recoveries
  tonight.

* IMPACTS...Any fires that develop will likely spread rapidly.

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.

&&

$$

048 
WWUS86 KMTR 102353
RFWMTR

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Francisco CA
453 PM PDT Thu Oct 10 2019


CAZ507-511-110100-
/O.EXP.KMTR.FW.W.0004.000000T0000Z-191011T0000Z/
North Bay Mountains-East Bay Hills and the Diablo Range-
453 PM PDT Thu Oct 10 2019

...RED FLAG WARNING WILL EXPIRE AT 5 PM PDT THIS AFTERNOON FOR DRY
OFFSHORE WINDS FOR FIRE WEATHER ZONES 507 AND 511...

Wind speeds will continue to diminish in the North Bay Mountains
and East Bay Hills through the evening and overnight hours. Some
localized areas around the Oakland Hills can expect another few 
hours of gusty offshore winds. While winds are forecast to 
subside, near-critical fire weather conditions are still expected 
through the overnight hours.

$$

CAZ506-510-110100-
/O.EXP.KMTR.FW.W.0004.000000T0000Z-191011T0000Z/
North Bay Interior Valleys-East Bay Interior Valleys-
453 PM PDT Thu Oct 10 2019

...RED FLAG WARNING WILL EXPIRE AT 5 PM PDT THIS AFTERNOON FOR DRY
OFFSHORE WINDS FOR FIRE WEATHER ZONES 506 AND 510...

The threat of gusty winds for the North Bay Valleys and East Bay
Interior Valleys will decrease through the evening and overnight
hours. While winds are forecast to subside, near-critical fire 
weather conditions can still be expected through the overnight 
hours.

$$

Area Forecast Discussion
National Weather Service San Francisco Bay Area
305 AM PDT Tue Oct 8 2019

.SYNOPSIS...A temporary return to onshore flow will mean cooler
temperatures today, especially in coastal areas. Strong, gusty
and dry northerly winds are then forecast to develop across the
greater San Francisco Bay Area by late tonight and continue
through Thursday. Strongest winds are expected in the hills, but
gusty winds will develop locally in the valleys and near the coast
as well. These conditions will result in critical fire weather
conditions from Wednesday into Thursday, especially across the
North Bay, East Bay, and Santa Cruz Mountains. Warmer daytime
temperatures are expected late in the week, followed by modest
cooling during the upcoming weekend.

&&

.DISCUSSION...As of 3:05 AM PDT Tuesday...Light onshore flow
developed late yesterday and a shallow marine layer is forming
near the coast early this morning. These developments will mean
cooler conditions in coastal areas today, with high temperatures
near the ocean and bays expected to be anywhere from 7 to 15
degrees cooler than yesterday. Due to the developing marine layer,
patchy fog is possible near the ocean today. Onshore flow is
expected to remain weak today and so inland areas are not forecast
to cool as much. Interior valley locations are projected to cool
by only about five degrees.

Early morning satellite imagery shows an upper trough over the
Pacific Northwest, moving to the southeast. This is a classic
"inside slider" system that will drop into the Great Basin and
generate ideal conditions for strong and gusty offshore winds
across much of the SF Bay Area starting late tonight and
continuing through Thursday. A dry cold front associated with the
upper trough is forecast to sweep from north to south across our
area from this evening through late tonight. Northwest winds will
increase behind the front this evening, particularly along the
North Bay Coast and locally in the hills. Winds in the North and
East Bay Hills will then veer to the north late tonight and
also increase, becoming strong and gusty by daybreak Wednesday.
North to northeast winds will remain strong and gusty in the hills
through Wednesday, and gradually become more widespread. Locally
gusty winds are expected to develop in the North and East Bay
Valleys by Wednesday afternoon and then develop farther south into
the Santa Cruz Mountains by Wednesday evening. Wind speeds are
expected to reach their peak intensity from Wednesday evening
through Thursday morning as surface high pressure builds strongly
into the Great Basin and offshore gradients peak. Sustained winds
of 20 to 30 mph, with gusts of 45 to 55 mph are expected across
the North and East Bay Hills during this the height of this event
on Wednesday night, with locally higher gusts possible. A Wind
Advisory will be issued for elevations above 1000 feet in the
North and East Bay Hills from 6 am Wednesday to 3 pm Thursday.
Winds are not expected to be as strong in the Santa Cruz Mountains
or in the valleys, and so Wind Advisories are not anticipated in
these areas. In fact, latest models have trended a bit weaker on
winds in the Santa Cruz Mountains. However, winds in all the
aforementioned areas will be strong enough to generate critical
fire weather conditions when combined with the expected very low
humidities and dry fuels. A Fire Weather Watch is currently in
effect for the North and East Bay Hills and Valleys, and the Santa
Cruz Mountains from late Tuesday Night through Thursday. This
watch will be upgraded to a Red Flag Warning this morning.

Our local WRF model also forecasts gusty offshore winds to
develop locally near the ocean late Wednesday night and early
Thursday, primarily in western Marin County near Stinson Beach,
in western San Mateo County near Half Moon Bay, and along the Big
Sur coast just south of Carmel. Because gusty winds in coastal
areas will be localized and of short duration, these areas are not
expected to be included in the impending Wind Advisories or Red
Flag Warnings.

Temperatures will initially cool tonight and Wednesday as a
cooler airmass spills south into our area. But temperatures will
quickly rebound by Thursday when the upper trough over the Great
Basin shifts eastward and a ridge develops just off the West
Coast. Also, the very dry airmass that will be in place across our
area by late Wednesday and Thursday will allow for large diurnal
temperatures variations later in the week when winds subside. High
temperatures will warm back into the 80s in most inland areas by
Friday, while valleys cool into the upper 30s at night. Modest
daytime cooling is then expected over the upcoming weekend when a
weak upper trough is forecast to move inland across the Pacific
Northwest and northern California.

&&

.AVIATION...as of 10:57 PM PDT Monday...For 06z TAFs. Mainly
clear skies will prevail through the forecast period with the
exception of a few high clouds passing overhead. Winds will
continue to decrease becoming light to locally variable overnight.
Have added wind shear to select terminals for Tuesday afternoon
and evening.

Vicinity of KSFO...VFR through the period with the exception
of a few high clouds passing overhead. Winds will continue to
decrease becoming light to locally variable overnight. Winds will
strengthen and become gusty around 15 to 25 kt in the afternoon.
Have added wind shear to KSFO, KOAK, and KSTS terminals for
Tuesday afternoon and continuing through late Tuesday night.

SFO Bridge Approach...Similar to KSFO.

Monterey Bay Terminals...VFR through the period. Light to locally
variable winds will prevail overnight. Winds will strengthen and
become gusty around 10 to 15 kt in the afternoon. Have added
wind shear to KMRY for Tuesday evening through late Tuesday
night.

&&

.FIRE WEATHER...As of 4:40 PM PDT Monday...Confidence continues
to increase regarding the development of critical fire weather
conditions midweek. A Fire Weather Watch is in effect from late
Tuesday night through Thursday for the North and East Bay Hills,
the North and East Bay Valleys, and the Santa Cruz Mountains.
While the strongest winds will likely occur in the North and East
Bay Hills, locally strong and gusty winds are also likely across
the higher ridges and peaks in the Santa Cruz Mountains. Also,
locally gusty winds may reach the valley floors at times in both
the North and East Bay. Strong and gusty offshore winds will
combine with critically dry conditions. The main message is to
prepare for the strongest offshore flow we've seen this season,
critically low daytime humidity with poor overnight recoveries,
and dry fuels, all resulting in critical fire weather conditions.

South of the SF Bay Area, winds during this upcoming event are
expected to be mostly light. However, locally gusty northeast
winds may develop in the northern Santa Lucia Mountains near the
Big Sur Coast for a brief period of time from late Wednesday night
into Thursday morning. Because these winds will be localized and
of short duration, this area has not been included in the Fire
Weather Watch.

The Fire Weather Watch will likely be transitioned to a Red Flag
Warning sometime on Monday, most likely in the early morning
hours. Once the watch transitions to a warning, the timing of the
event will be fine-tuned.

&&

.MARINE...As of 2:52 AM PDT Tuesday...Northwest winds will
increase and become northerly tonight and Wednesday as a strong
high pressure system drops into the Great Basin. Gale force
conditions will develop over the northern waters this afternoon
and spread into the southern outer waters tonight. Strong winds
will increase wind waves creating hazardous seas conditions
through midweek.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tday...SCA...Pt Arena to Pigeon Pt 10-60 nm until 3 PM
             GLW...Pt Arena to Pigeon Pt 10-60 nm from 3 PM
             SCA...Pt Reyes to Pigeon Pt 0-10 nm from 5 PM
             SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm from 5 PM
             SCA...Pigeon Pt to Pt Piedras Blancas 10-60 nm from 5 PM
             SCA...Pt Arena to Pt Reyes 0-10 nm from 9 AM

&&

PUBLIC FORECAST: Dykema
AVIATION: CW
MARINE: W Pi
FIRE WEATHER: Dykema

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