Alert archive / Alaska / Red Flag Warnings in 2019

Red Flag Warning 1, NWS Anchorage, AK

July 9, 2019

NWS Anchorage, AK issued this red flag warning at Jul 9, 2019, 4:04 PM AKDT. It took effect at Jul 10, 2019, 2:00 PM AKDT. It was in force for 35 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
Jul 9, 2019, 4:04 PM AKDT (00:04 UTC)
In effect from
Jul 10, 2019, 2:00 PM AKDT
Expired
Jul 12, 2019, 1:00 AM AKDT
In force
35 hr
Issued by
NWS Anchorage, AK

The text

As transmitted.

775 
WWAK61 PAFC 100004
RFWAER

URGENT - FIRE WEATHER MESSAGE
National Weather Service Anchorage AK
404 PM AKDT Tue Jul 9 2019

AKZ141-101615-
/O.NEW.PAFC.FW.W.0001.190710T2200Z-190712T0600Z/
404 PM AKDT Tue Jul 9 2019

...RED FLAG WARNING IN EFFECT FROM 2 PM WEDNESDAY TO 10 PM AKDT
THURSDAY FOR LIGHTNING FOR THE COPPER RIVER BASIN...

The National Weather Service in Anchorage has issued a Red Flag
Warning FOR LIGHTNING, which is in effect from 2 PM Wednesday to
10 PM AKDT Thursday.

* Location...Wednesday thunderstorm activity will mainly favor
  higher terrain and adjacent areas, while Thursday will be more
  widespread across the entire basin. 

* Lightning Activity Level...3 to 4.

* Winds...Variable 5 to 10 mph Wednesday. Thursday, a Copper River
  Wind will develop...south winds 10 to 20 mph.

* Relative Humidity...As low as 37 percent.

* Temperatures...In the 70s.

* Timing...Red Flag conditions will mainly be during the day,
  however, some overnight thunderstorm activity is possible
  Wednesday into Thursday.

* Impacts...Ample lightning could lead to numerous new fire 
  starts

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A red flag warning means that critical fire weather conditions
are imminent or occurring now, or will shortly. It is directed
toward fire agencies, and through them to the public.

&&

$$
6 follow-up statements
734 
WWAK61 PAFC 101446
RFWAER

URGENT - FIRE WEATHER MESSAGE
National Weather Service Anchorage AK
646 AM AKDT Wed Jul 10 2019

AKZ141-110700-
/O.CON.PAFC.FW.W.0001.190710T2200Z-190712T0600Z/
646 AM AKDT Wed Jul 10 2019

...RED FLAG WARNING REMAINS IN EFFECT FROM 2 PM THIS AFTERNOON TO
10 PM AKDT THURSDAY FOR LIGHTNING FOR THE COPPER RIVER BASIN...

* Location...Today's thunderstorm activity will mainly favor 
  higher terrain and adjacent areas, while Thursday will be more 
  widespread across the entire basin.

* Lightning Activity Level...3 to 4.

* Winds...Variable 5 to 10 mph today. Thursday: Southwest winds 5
  to 10 mph except south wind 10 to 15 mph near the Copper River.

* Relative Humidity...As low as 35 percent.

* Temperatures...Highs in the 80s today and 70s.

* Timing...Red Flag conditions will mainly be during the day, 
  however, some overnight thunderstorm activity is possible 
  Wednesday into Thursday.

* Impacts...Ample lightning could lead to numerous new fire 
  starts

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A red flag warning means that critical fire weather conditions
are imminent or occurring now, or will shortly. It is directed
toward fire agencies, and through them to the public.

&&

$$
073 
WWAK61 PAFC 110004
RFWAER

URGENT - FIRE WEATHER MESSAGE
National Weather Service Anchorage AK
404 PM AKDT Wed Jul 10 2019

AKZ141-111615-
/O.CON.PAFC.FW.W.0001.000000T0000Z-190712T0600Z/
404 PM AKDT Wed Jul 10 2019

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 10 PM AKDT THURSDAY
FOR LIGHTNING FOR THE COPPER RIVER BASIN...

* Location...This evening's thunderstorm activity will mainly 
  favor higher terrain and adjacent areas, while Thursday will be 
  more widespread across the entire basin.

* Lightning Activity Level...3 to 4.

* Winds...Today: Variable 5 to 10 mph. Thursday: Southwest winds 
  5 to 10 mph except south wind 10 to 15 mph near the Copper 
  River.

* Relative Humidity...As low as 35 percent.

* Temperatures...Highs in the 80s today and 70s Thursday.

* Timing...Red Flag conditions will mainly be during the day, 
  however, some overnight thunderstorm activity is possible 
  Wednesday into Thursday.

* Impacts...Ample lightning could lead to numerous new fire 
  starts

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A red flag warning means that critical fire weather conditions
are imminent or occurring now, or will shortly. It is directed
toward fire agencies, and through them to the public.

&&

$$
724 
WWAK61 PAFC 111534
RFWAER

URGENT - FIRE WEATHER MESSAGE
National Weather Service Anchorage AK
734 AM AKDT Thu Jul 11 2019

AKZ141-120600-
/O.CON.PAFC.FW.W.0001.000000T0000Z-190712T0600Z/
734 AM AKDT Thu Jul 11 2019

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 10 PM AKDT THURSDAY
FOR LIGHTNING FOR THE COPPER RIVER BASIN...

* Location...This evening's thunderstorm activity will mainly 
  favor higher terrain and adjacent areas, while Thursday will be 
  more widespread across the entire basin.

* Lightning Activity Level...3 to 4.

* Winds...Variable 5 to 10 mph today. Thursday: Southwest winds 
  5 to 10 mph except south wind 10 to 15 mph near the Copper 
  River.

* Relative Humidity...As low as 35 percent.

* Temperatures...Highs in the 80s today and 70s Thursday.

* Timing...Red Flag conditions will mainly be during the day, 
  however, some overnight thunderstorm activity is possible 
  Wednesday into Thursday.

* Impacts...Ample lightning could lead to numerous new fire 
  starts

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A red flag warning means that critical fire weather conditions
are imminent or occurring now, or will shortly. It is directed
toward fire agencies, and through them to the public.

&&

$$
408 
WWAK61 PAFC 120003
RFWAER

URGENT - FIRE WEATHER MESSAGE
National Weather Service Anchorage AK
403 PM AKDT Thu Jul 11 2019

AKZ141-120600-
/O.CON.PAFC.FW.W.0001.000000T0000Z-190712T0600Z/
403 PM AKDT Thu Jul 11 2019

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 10 PM AKDT THIS
EVENING FOR LIGHTNING FOR THE COPPER RIVER BASIN...

* Location...This evening's thunderstorm activity will mainly
  favor higher terrain and adjacent areas while some activity will
  be noted across the entire basin.

* Lightning Activity Level...3 to 4.

* Winds...Southwest 5 to 10 mph.

* Relative Humidity...As low as 41 percent.

* Temperatures...60 to 74.

* Timing...Red Flag conditions persist into the evening hours
  until thunderstorm activity decreases overnight.

* Impacts...Ample lightning could lead to new fire starts

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A red flag warning means that critical fire weather conditions
are imminent or occurring now, or will shortly. It is directed
toward fire agencies, and through them to the public.

&&

$$
999 
WWAK61 PAFC 120536
RFWAER

URGENT - FIRE WEATHER MESSAGE
National Weather Service Anchorage AK
936 PM AKDT Thu Jul 11 2019

AKZ141-120900-
/O.EXT.PAFC.FW.W.0001.000000T0000Z-190712T0900Z/
936 PM AKDT Thu Jul 11 2019

...RED FLAG WARNING NOW IN EFFECT UNTIL 1 AM AKDT FRIDAY FOR
LIGHTNING FOR THE COPPER RIVER BASIN...

* Location...Tonight's thunderstorm activity will mainly favor 
  higher terrain and adjacent areas while some activity will be 
  noted across the entire basin.

* Lightning Activity Level...3 to 4.

* Winds...Southwest 5 to 10 mph.

* Relative Humidity...As low as 41 percent.

* Temperatures...60 to 74.

* Timing...Red Flag conditions persist into the overnight hours
  until thunderstorm activity decreases late tonight.

* Impacts...Ample lightning could lead to new fire starts.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A red flag warning means that critical fire weather conditions
are imminent or occurring now, or will shortly. It is directed
toward fire agencies, and through them to the public.

&&

$$
016 
WWAK61 PAFC 120900
RFWAER

URGENT - FIRE WEATHER MESSAGE
National Weather Service Anchorage AK
100 AM AKDT Fri Jul 12 2019

AKZ141-121000-
/O.EXP.PAFC.FW.W.0001.000000T0000Z-190712T0900Z/
100 AM AKDT Fri Jul 12 2019

...RED FLAG WARNING FOR THE COPPER RIVER BASIN HAS EXPIRED...

The Red Flag Warning has expired.

$$

What forecasters said that day

The local office's own words before this red flag warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Anchorage, AK wrote its last area forecast discussion before this red flag warning went out at Jul 9, 5:21 AM AKDT, 10 hours 43 minutes earlier.

Area forecast discussion, Jul 9, 5:21 AM AKDT, 10 hours 43 minutes before
Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
521 AM AKDT Tue Jul 9 2019

.ANALYSIS AND UPPER LEVELS...

The upper level pattern continues to feature a trough-ridge
pattern over Southern Alaska. The ridge has been dominating the
weather over the mainland for several weeks now. The center of the
upper level high is over the Seward Peninsula, with the ridge
extending southwestward across much of Southern Alaska. This is
causing northeasterly upper level winds over the area. The trough
and associated vertically-stacked low is centered over Adak, with
associated shower activity ongoing across the central and western
Aleutians. The weakening ridging is allowing for isolated
thunderstorms to develop over the area mountains. Yesterday there
were a couple that formed over the Talkeetnas and the Alaska
Range, respectively.

Smoke from area wildfires has enveloped nearly all of Southern
Alaska this morning. A Dense Smoke Advisory remains in effect for
the Western Kenai Peninsula for the Swan Lake fire. Dense Smoke
Advisories have also been issued for the Lower Kuskokwim Valley
and the Kuskokwim Delta, with smoke from the Old Grouch Mountain,
Hurst Creek, and Foraker fires expected to reduce visibilities to
one quarter mile at times this morning.

&&

.MODEL DISCUSSION...

The models remain in very good synoptic agreement, with some
differences in the placement of the low approaching the central
Aleutians late Wednesday night into Thursday. However, since the
low is weak the difference in the weather regardless of model
choice is minimal. Forecast challenges abound in regards to the
local effects. Thunderstorm coverage and number remains a large
point of uncertainty over the coming days. As the atmosphere
destabilizes and the ridge weakens, the threat for storms will
increase, especially along the mountains and when any stronger
waves move through. Smoke density will also be another point of
uncertainty since hazy smoke now covers much of the area. Finally,
temperatures will be challenging, with sea breezes near the
coast, including Anchorage, likely playing a major role in how
warm temperatures get. Overall forecast confidence remains high,
especially as regards impactful weather.

&&

.AVIATION...
PANC...VFR conditions and light winds will persist for the most
part. Smoke from the Swan Lake Fire will continue to be the only
weather concern, with the lowest visibilities expected in the
mornings, with periods of MVFR conditions.

&&

.FIRE WEATHER...

Southcentral Alaska... Starting with the good news: The record-
breaking heat that has been common across nearly all of
Southcentral is finally going to begin abating today. The upper
level ridge that has capped the atmosphere and prevented any
thunderstorms and associated cloud cover is weakening and moving
north and west away from Southern Alaska. Southerly onshore up-
Inlet windflow off the Gulf will also begin to cool coastal
locations, including Anchorage today. The cooler, marine air will
both lower temperatures and increase the humidity. Minimum
relative humidity values will also climb from the 20-40 percent
range today into the 50-60 percent range by Thursday.
Predominately southerly winds up the Inlet may not help air
quality concerns much in Anchorage and the Matanuska Valley with
the Swan Lake Fire, but overall smoke conditions will improve
since the wildfire smoke will move north into interior Alaska
instead of lingering in the skies above Southcentral.

Now the bad news: Besides air quality being unlikely to improve
much in Anchorage and the Mat-Su Valleys, thunderstorm potential
is expected to continue increasing compared with the weather
pattern the past few weeks. As usual, the greatest potential for
thunderstorms will be over the mountains, and the increasing
moisture will only add more fuel for any storms. While moisture
levels are high enough that most of the storms should produce rain
with them, cloud-to-ground lightning and associated gusty winds
can occur well away from the rainy part of the storm.

Southwest Alaska...The dominant upper level ridge is retreating
northward and weakening, and this will result in temperatures
trending back toward seasonal normals with increasing RH values.
Because of the weakening ridge, expect thunderstorms today to be a
little more widespread along and near the Alaska Range with some
isolated wet thunderstorms farther west along the
Kilbuck/Kuskokwim Mountains. Wednesday and Thursday, the flow
switches to onshore which will advect more moisture north into the
interior, so expect even more widespread shower/thunderstorm
activity and increasing chances for wetting rains. Smoke from
interior fires will be at their worst this morning, then lift and
move north the next couple days.

&&

.CLIMATE...

Numerous high temperature records were set across Southern Alaska
yet again yesterday. Here is a list of a number of them:

Location..................New Record...Old Record (Most Recent
Year)

Anchorage International...85 degrees...84 degrees (2003)
Anchorage Merrill Field...86 degrees...84 degrees (2003)
Kenai.....................83 degrees...82 degrees (2003)
Talkeetna.................91 degrees...89 degrees (2003)
Palmer....................84 degrees...84 degrees (2009)
Iliamna...................84 degrees...84 degrees (2003)
King Salmon...............83 degrees...82 degrees (2004)

Consecutive Days with daily record highs through July 8th:

Anchorage International...6 days
Anchorage Merrill Field...7 days (1915 records excluded as bad data)
Kenai.....................1 day
Talkeetna.................4 days
Palmer....................7 days
Iliamna...................5 days
King Salmon...............5 days

IMPORTANT NOTE: The thermometer at the airport in Bethel is
broken and its data are considered unreliable. Thus, all recent
temperature readings from there are not being included in any
official climate record. A technician will be going to fix the
thermometer there soon.

More climate records will be included in upcoming mornings for
Anchorage International.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...

We are beginning to transition away from the extreme (for Alaska)
heat that the region has been experiencing the past week.
Temperatures over most of the area should be noticeably cooler
than yesterday and tomorrow even more so. Temperatures today would
normally be referred to as hot except compared to the past week
they will be cooler! This is all due to the ridge continuing to
weaken and move away form Southcentral Alaska. What this also
does is increase the potential for afternoon and evening
thunderstorms over the mountains. Today and tomorrow will see an
uptick these storms as the subsidence from the ridge is no longer
around to keep them at bay. However the warm air at the surface
and cooling temperatures aloft are making the atmosphere more
unstable.

The stratus is still hanging out at the southern end of Cook Inlet
and has been unable to make much headway up the Inlet due to the
warm airmass. This may change as the week progresses and the
advance of the marine layer up the Inlet could become an important
weather event for the Western Kenai Peninsula and perhaps as far
north as Anchorage.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 through 3)... The
dominant and strong closed blocking high which has been in place
across Southern Alaska for the last several days will finally
retreat north and weaken, allowing for a gradual downtrend in
daytime high temps. Thunderstorm activity will also increase,
first along the mountains today, then inland Wednesday and
Thursday, especially across the Lower Kuskokwim Valley and
interior mountains and into the Kuskokwim Delta. Uncertainty rises
both days as varying models solutions are depicting more
organized showers/thunderstorms moving farther west into the
Kuskokwim Delta in association with an "easterly wave", especially
Wednesday night. broad onshore flow will develop across coastal
regions as the interior low strengthens, so coastal areas will be
thunderstorm free (especially across Bristol Bay) as cooler air
moves north.

Wildfire smoke will be at its worst this morning, then it will
gradually improve as daytime heating commences and the steering
flow moves northward. Since the worst fires are northward, this
should allow dense smoke to end by midday today.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
A broad and diffuse low over the western/central Bering Sea and
Aleutians will remain in place, keep cyclonic winds and
intermittent light rain over most of the Bering Sea west and south
of the Pribilof Islands. Sea stratus and fog will also be ever
present with the weather pattern remaining stagnant through
Thursday night as another low and associated front move in and
replace the current system. The quietest weather will be over the
eastern Bering where the main weather challenge will be fog and
stratus as winds will remain weakly onshore along the Southwest
mainland coast.

&&

.MARINE (Days 3 through 5)...
(Saturday through Monday)

Relatively benign conditions will persist across the Bering Sea,
Aleutian coastal waters, and the Gulf of Alaska through the
period. Look for sustained winds and wave heights to remain below
small craft conditions.

&&

.LONG TERM FORECAST (Days 3 through 7)...
(Saturday through Wednesday)

The persistent weather pattern that's been in place for the better
part of two weeks now will undergo some modification for the
weekend into next week. This will occur as a low, currently
centered near Adak, sends a few ripples of energy eastward into
the Gulf. Meanwhile, another area of low pressure will reposition
to the Arctic coast of the Northwest Territories/Yukon area of
Canada. Several disturbances will dive southeast then east across
the northern third of the state.

The net effect is for the ridge of high pressure that's stretched
from the Gulf to eastern Siberia gets undercut by the Aleutians
low sending vort maxes (small areas of increased lift and
ascent...or essentially weak mid level areas of low pressure) into
the southern Gulf, while the Canadian low flattens the ridge from
the northeast as several disturbances round its base. This in
turn stretches the high pressure ridge axis somewhat, kind of
like a rubber band) as the Gulf high moves somewhat southeast,
with the Siberian high retrograding west some.

With this increased separation of distance between the two high
pressure centers, the thermal trough also weakens, with 850 mb
temperatures cooling some 6 to 10 degrees Celsius, with a
corresponding decrease in afternoon high temperatures likely for
all of southwest and southcentral Alaska. However, this will only
knock highs back into the lower to mid 70s, which is still well
above average for this time of year.

The other thing this separation does is create the likelihood of
increased convective coverage, even if just scattered in coverage
at best, given less subsidence and disturbances glancing the area
as the ridge the edges of the ridge of high pressure. These
disturbances in turn help cool the atmosphere aloft while
increasing wind speeds up higher up, helping to allow the air to
rise more freely. As a result, this could potentially open the
door for better thunderstorm coverage, and given the recent heat
dome thats entrenched the state, a few strong storms would be
possible.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Dense Smoke Advisory 121 152 155.
MARINE...NONE.
FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...JPW
FIRE WEATHER...JPW & JA
CLIMATE...JPW
SOUTHCENTRAL ALASKA...EZ
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...JA
MARINE/LONG TERM...PD

In the hours before

Special weather statement, Jul 9, 3:03 PM AKDT, 1 hour 1 minute before
SPECIAL WEATHER STATEMENT
National Weather Service ANCHORAGE AK
303 PM AKDT Tue Jul 9 2019

AKZ101-111-121-125-141-145-112315-
Anchorage-Matanuska Valley-Western Kenai Peninsula-
Western Prince William Sound-Copper River Basin-Susitna Valley-
Including the cities of Anchorage, Eagle River, Indian, Eklutna,
Palmer, Wasilla, Sutton, Chickaloon, Kenai, Soldotna, Homer,
Cooper Landing, Whittier, Seward, Girdwood, Moose Pass,
Glennallen, Eureka, McCarthy, Paxson, Slana, Talkeetna, Willow,
and Cantwell
303 PM AKDT Tue Jul 9 2019

...ELEVATED WATER LEVELS ON RIVERS AND STREAMS ACROSS
SOUTHCENTRAL...

Many rivers across southcentral continue to be at or near bankfull
stages due to the warm weather and glacial melt.

The Kenai River below Skilak Lake is at minor flood stage with
water in yards and in one garage.

Elevated water levels persist for Eagle River. For those near or
attempting to cross Eagle River as part of the Crow Pass Trail, be
prepared for very high and swift water.

Along the Richardson Highway, the Klutina and Tazlina Rivers
remain near bankfull stages.

Water levels across the region should decrease with a change to
cooler temperatures over the next few days.

The office that day

Everything else NWS Anchorage, AK issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 9, 5:38 PM AKDTRed Flag WarningAFC55 hr
Jul 10, 3:48 AM AKDTSmall Craft AdvisoryAFC60 hr

Nearby

Red Flag Warnings in Alaska, 2019Every red flag warning in 2019

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text.