Alert archive / California / Red Flag Warnings in 2021

Red Flag Warning 6, NWS Eureka, CA

September 19, 2021

NWS Eureka, CA issued this red flag warning at Sep 19, 2021, 10:21 AM PDT. It took effect at Sep 19, 2021, 11:00 PM PDT. It was in force for 27 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Sep 19, 2021, 10:21 AM PDT (17:21 UTC)
In effect from
Sep 19, 2021, 11:00 PM PDT
Expired
Sep 21, 2021, 2:00 AM PDT
In force
27 hr
Issued by
NWS Eureka, CA

The text

As transmitted.

111 
WWUS86 KEKA 191721
RFWEKA

Urgent - Fire Weather Message
National Weather Service Eureka CA
1021 AM PDT Sun Sep 19 2021

...Gusty Offshore Winds and Increasingly Dry Conditions Tonight
through Monday Evening...

.An early autumn offshore flow event will impact portions of
interior northwest California beginning tonight and continuing
Monday.

Although substantial wetting rainfall dampened dry and dead
vegetation over some parts of northern and far western Lake
County, rainfall amounts across the rest of Lake County were very
light, with just sprinkles in some areas. As high pressure builds
in quickly to our north tonight into Monday, winds will shift 
from northwesterly to northeasterly and become gusty, especially 
over exposed higher slopes and ridges. This wind will bring in 
much drier air, followed by a hotter and drier days Monday and
Tuesday. Some locally breezy conditions may persist over the 
exposed ridgetops Monday night, but expect winds will be trend 
lighter overall through Tuesday. However, humidity recoveries 
heading into Tuesday morning will be much poorer, especially over 
all upper slopes and ridges that did not see wetting rains over 
the weekend.


CAZ264-200130-
/O.UPG.KEKA.FW.A.0006.210920T0600Z-210921T0000Z/
/O.NEW.KEKA.FW.W.0006.210920T0600Z-210921T0300Z/
Lake County Portion of Lake/Napa/Sonoma RU-
1021 AM PDT Sun Sep 19 2021

...RED FLAG WARNING IN EFFECT FROM 11 PM THIS EVENING TO 8 PM PDT
MONDAY...

The National Weather Service in Eureka has issued a Red Flag
Warning, which is in effect from 11 PM this evening to 8 PM PDT
Monday. The Fire Weather Watch has been upgraded. 

* WIND...Northeast 10 to 20 mph. Gusts 30 to 40 mph over exposed 
  ridgetops. 

* HUMIDITY...Recoveries of 40 to 60 percent tonight into Monday
  morning...lowest over ridgetops. Humidity in the low to mid
  teens Monday afternoon. Humidity recoveries Tuesday morning 
  only in the 25 to 40 percent range.

* IMPACTS...In all areas that did not see any wetting rain
  Saturday night, any fire starts will likely spread rapidly due 
  to dry fuels, low humidity and gusty winds. 


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.

&&

$$


http://weather.gov/eureka
5 follow-up statements
191 
WWUS86 KEKA 200115
RFWEKA

Urgent - Fire Weather Message
National Weather Service Eureka CA
615 PM PDT Sun Sep 19 2021

...Gusty Offshore Winds and Increasingly Dry Conditions Tonight
through Monday Evening...

.An early autumn offshore flow event will impact portions of
interior northwest California beginning tonight and continuing
Monday.

Although substantial wetting rainfall dampened dry and dead
vegetation over some parts of northern and far western Lake
County, rainfall amounts across the rest of Lake County were very
light, with just sprinkles in some areas. As high pressure builds
in quickly to our north tonight into Monday, winds will shift
from northwesterly to northeasterly and become gusty, especially
over exposed higher slopes and ridges. This wind will bring in
much drier air, followed by a hotter and drier days Monday and
Tuesday. Some locally breezy conditions may persist over the
exposed ridgetops Monday night, but expect winds will be trend
lighter overall through Tuesday. However, humidity recoveries
heading into Tuesday morning will be much poorer, especially over
all upper slopes and ridges that did not see wetting rains over
the weekend.

CAZ264-201030-
/O.CON.KEKA.FW.W.0006.210920T0600Z-210921T0300Z/
Lake County Portion of Lake/Napa/Sonoma RU-
615 PM PDT Sun Sep 19 2021

...RED FLAG WARNING REMAINS IN EFFECT FROM 11 PM THIS EVENING TO
8 PM PDT MONDAY...

* WIND...Northeast 10 to 20 mph. Gusts 30 to 40 mph over exposed 
  ridgetops. 

* HUMIDITY...Recoveries of 40 to 60 percent tonight into Monday 
  morning...lowest over ridgetops. Humidity in the low to mid 
  teens Monday afternoon. Humidity recoveries Tuesday morning 
  only in the 25 to 40 percent range.

* IMPACTS...In all areas that did not see any wetting rain 
  Saturday night, any fire starts will likely spread rapidly 
  due to dry fuels, low humidity and gusty winds.

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.

&&

$$

http://weather.gov/eureka
863 
WWUS86 KEKA 200553
RFWEKA

Urgent - Fire Weather Message
National Weather Service Eureka CA
1053 PM PDT Sun Sep 19 2021

...Gusty Offshore Winds and Increasingly Dry Conditions Tonight
through Monday Evening...

.An early autumn offshore flow event will impact portions of
interior northwest California beginning tonight and continuing
Monday.

Although substantial wetting rainfall dampened dry and dead
vegetation over some parts of northern and far western Lake
County, rainfall amounts across the rest of Lake County were very
light, with just sprinkles in some areas. As high pressure builds
in quickly to our north tonight into Monday, winds will shift
from northwesterly to northeasterly and become gusty, especially
over exposed higher slopes and ridges. This wind will bring in
much drier air, followed by a hotter and drier days Monday and
Tuesday. Some locally breezy conditions may persist over the
exposed ridgetops Monday night, but expect winds will be trend
lighter overall through Tuesday. However, humidity recoveries
heading into Tuesday morning will be much poorer, especially over
all upper slopes and ridges that did not see wetting rains over
the weekend.

CAZ264-201400-
/O.CON.KEKA.FW.W.0006.210920T0600Z-210921T0300Z/
Lake County Portion of Lake/Napa/Sonoma RU-
1053 PM PDT Sun Sep 19 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM PDT MONDAY...

* WIND...Northeast 10 to 20 mph. Gusts 30 to 40 mph over exposed 
  ridgetops. 

* HUMIDITY...Recoveries of 40 to 60 percent tonight into Monday 
  morning...lowest over ridgetops. Humidity in the low to mid 
  teens Monday afternoon. Humidity recoveries Tuesday morning 
  only in the 25 to 40 percent range.

* IMPACTS...In all areas that did not see any wetting rain 
  Saturday night, any fire starts will likely spread rapidly 
  due to dry fuels, low humidity and gusty winds.

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.

&&

$$


http://weather.gov/eureka
707 
WWUS86 KEKA 201345
RFWEKA

Urgent - Fire Weather Message
National Weather Service Eureka CA
645 AM PDT Mon Sep 20 2021

...Gusty Offshore Winds and Increasingly Dry Conditions through 
Evening...

.An early autumn offshore flow event is impacting portions of 
interior northwest California today.

High pressure building across the area allowed offshore flow with 
gusty northeasterly winds, especially over exposed higher slopes 
and ridges. Hotter and drier days is expected today and Tuesday. 
Some locally breezy conditions may persist over the exposed 
ridgetops tonight, but expect winds will be trend lighter overall
through Tuesday. However, humidity recoveries heading into 
Tuesday morning will be much poorer, especially over all upper 
slopes and ridges that did not see wetting rains over the weekend.

CAZ264-202145-
/O.CON.KEKA.FW.W.0006.000000T0000Z-210921T0300Z/
Lake County Portion of Lake/Napa/Sonoma RU-
645 AM PDT Mon Sep 20 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM PDT THIS
EVENING...

* WIND...Northeast 10 to 20 mph. Gusts 30 to 40 mph over exposed 
  ridgetops. 

* HUMIDITY...Recoveries of 40 to 60 percent tonight into Monday 
  morning...lowest over ridgetops. Humidity in the low to mid 
  teens Monday afternoon. Humidity recoveries Tuesday morning 
  only in the 25 to 40 percent range.

* IMPACTS...In all areas that did not see any wetting rain 
  Saturday night, any fire starts will likely spread rapidly 
  due to dry fuels, low humidity and gusty winds.

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.

&&

$$


http://weather.gov/eureka
290 
WWUS86 KEKA 201627
RFWEKA

Urgent - Fire Weather Message
National Weather Service Eureka CA
927 AM PDT Mon Sep 20 2021

...Gusty Offshore Winds and Increasingly Dry Conditions today 
into tonight...

.An early autumn offshore wind event is impacting a portion of 
interior northwest California, mainly around Lake County. 
Localized breezy conditions will continue into tonight over some 
ridgetops, with very poor overnight humidity recoveries. 

After very little to no rain fell around much of Lake County over
the weekend, high pressure building in to our north and east 
brought gusty northeasterly winds overnight and this morning, 
mainly over exposed higher slopes and ridges. Some of those winds 
will mix down into the valleys and around Clearlake today, but not
as strong as we have seen over the ridgetops. That will be 
accompanied by a very warm and dry afternoon and evening. Lower 
slopes and valley winds will calm down this evening, but over 
higher slopes and ridges winds will stay locally gusty, before 
relaxing after midnight. Overnight humidity recoveries will be 
exceptionally poor over those higher slopes and ridgetops tonight.



CAZ264-210130-
/O.EXT.KEKA.FW.W.0006.000000T0000Z-210921T0900Z/
Lake County Portion of Lake/Napa/Sonoma RU-
927 AM PDT Mon Sep 20 2021

...RED FLAG WARNING NOW IN EFFECT UNTIL 2 AM PDT TUESDAY...

* WIND...Northeast 10 to 20 mph today. Gusts 30 to 40 mph over
  exposed ridgetops. Winds will ease tonight, except over ridges
  and upper slopes where they will remain North-northeast 10 to 
  20 mph with some local gusts to 30 mph. 

* HUMIDITY...Humidity in the low to mid teens this afternoon.
  Humidity recoveries Tuesday morning only in the 20 to 40 percent
  range for upper slopes and ridges. 

* IMPACTS...In all areas that did not see wetting rain over the
  weekend, any new fire starts will likely spread rapidly due to 
  dry fuels, low humidity and gusty winds.

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. Please avoid any activities 
that could cause sparks or start a fire. 

&&

$$


http://weather.gov/eureka
372 
WWUS86 KEKA 210129
RFWEKA

Urgent - Fire Weather Message
National Weather Service Eureka CA
629 PM PDT Mon Sep 20 2021

...Gusty Offshore Winds and Increasingly Dry Conditions today
into tonight...

.An early autumn offshore wind event is impacting a portion of
interior northwest California, mainly around Lake County.
Localized breezy conditions will continue into tonight over some
ridgetops, with very poor overnight humidity recoveries.

After very little to no rain fell around much of Lake County over
the weekend, high pressure building in to our north and east
brought gusty northeasterly winds overnight and this morning,
mainly over exposed higher slopes and ridges. Some of those winds
will mix down into the valleys and around Clearlake today, but
not as strong as we have seen over the ridgetops. That will be
accompanied by a very warm and dry afternoon and evening. Lower
slopes and valley winds will calm down this evening, but over
higher slopes and ridges winds will stay locally gusty, before
relaxing after midnight. Overnight humidity recoveries will be
exceptionally poor over those higher slopes and ridgetops
tonight.

CAZ264-210900-
/O.CON.KEKA.FW.W.0006.000000T0000Z-210921T0900Z/
Lake County Portion of Lake/Napa/Sonoma RU-
629 PM PDT Mon Sep 20 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 2 AM PDT TUESDAY...

* WIND...Northeast 10 to 20 mph today. Gusts 30 to 40 mph over 
  exposed ridgetops. Winds will ease tonight, except over ridges 
  and upper slopes where they will remain North-northeast 10 to 
  20 mph with some local gusts to 30 mph. 

* HUMIDITY...Humidity in the low to mid teens this afternoon. 
  Humidity recoveries Tuesday morning only in the 20 to 40 
  percent range for upper slopes and ridges. 

* IMPACTS...In all areas that did not see wetting rain over the 
  weekend, any new fire starts will likely spread rapidly due 
  to dry fuels, low humidity and gusty winds.

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. Please avoid any activities
that could cause sparks or start a fire.

&&

$$

http://weather.gov/eureka

The office that day

Everything else NWS Eureka, CA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 19, 3:23 AM PDTSmall Craft AdvisoryEKA54 hr

Nearby

Red Flag Warnings in California, 2021Every red flag warning 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.