A 965 mb low pressure system in the Gulf of Alaska brought warm air aloft over Southcentral. Meanwhile, a 1025 mb high pressure system over the Arctic Ocean held cold air in place at the surface.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS AFC wrote it up.
A 965 mb low pressure system in the Gulf of Alaska brought warm air aloft over Southcentral. Meanwhile, a 1025 mb high pressure system over the Arctic Ocean held cold air in place at the surface. The large pressure difference between these two system also caused windy conditions around Southcentral. Precipitation in areas that had warm air aloft fell as rain, while areas that remained below freezing in the upper levels received snow. This contributed to blizzard conditions in some areas as well.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Anchorage, AK wrote its last area forecast discussion before the first event at Nov 13, 4:39 AM AKST, 1 hour 1 minute earlier.
Southcentral and Southwest Alaska Forecast Discussion...CORRECTED
National Weather Service Anchorage AK
439 AM AKST Wed Nov 13 2019
.ANALYSIS AND UPPER LEVELS...
A 949 mb storm-force low is situated well south of Cold Bay. Its
occluded front stretches from the western Gulf back across the
AKPEN and eastern Aleutians. Widespread areas of rain are falling
ahead of the front from coastal Bristol Bay west across the
Aleutians to Atka. Easterly gales are also occurring along the
front as well as northwesterly gales across the western and
central Aleutians as colder air spills south over the Bering and
wraps around the backside of the low.
Across the southern mainland, a northerly flow persists this
morning with gusty outflow winds along the southcentral coast as a
tight pressure gradient remains between the low nearing the Gulf
and a 1038 mb high anchored north of the Brooks Range. The
northerly flow is keeping arctic air in place over the Copper
River Basin and Susitna Valley, as well as the Kuskokwim Valley
and interior Southwest, with temperatures this morning mainly in
the single digits and teens for these locations.
Elsewhere, rain and fog continue for Kodiak City with clouds
increasing across coastal Southcentral as the occluded front
lifts further into the Gulf. Radar returns are also showing bands
of precipitation moving north across the Barren Islands, extreme
southern Kenai Peninsula, and Prince William Sound. However, with
drier air at the surface (dewpoints in the 20s with temperatures
in the mid 30s to lower 40s), these initial bands of precipitation
are not yet making it to the ground.
&&
.MODEL DISCUSSION...
Forecast guidance continues to depict a significant winter
weather event Wednesday and Thursday for parts of Southcentral,
but continues to struggle on the finer details when it comes to
timing of precipitation, as well as precipitation type and amount.
There is good model agreement that enough cold air will remain in
place across Thompson Pass and the Copper River Basin for these
locations to see all snow. Recent hi-res and global model runs,
have shifted the surface features and upper-level support slightly
more westward as they track through the northern Gulf; however,
this minor shift looks to yield little change, if any, to the
forecast for the aforementioned areas.
The greatest discrepancies between the models continue to be over
the western Kenai Peninsula, Anchorage Bowl, and Mat-Su Valleys
and concern timing of precipitation as well as precipitation type
and amount. There are differences in the models regarding the
initial push of moisture this morning along the western Kenai
Peninsula, lifting north to Anchorage this afternoon,
specifically how much the dry northeasterly low-level flow and
potential downsloping plays a role. Some hi-res models, along with
the GEM and NAMnest, indicate a brief period of light freezing
rain developing over the aforementioned areas in the late morning
to mid-afternoon before drying out. Others, like the GFS, are
drier. Almost all guidance then brings a second round of
precipitation to the region Wed night into Thu morning as a
frontal zone lifts north while an upper-level vorticity max moves
overhead, providing additional support. While there is good
agreement on this set up, models again waiver on the exact
position and strength of these features. The global models try to
keep the best dynamics over the Kenai Peninsula while the hi-res
models bring it up over Anchorage. Precipitation intensity and
type will also be driven by the set up of the smaller mesoscale
features, with guidance suggesting freezing rain/drizzle with
lighter precipitation rates and snow possible with heavier rates.
Bottom line, forecast confidence in precipitation type and amount
remains below average through this event.
&&
.AVIATION...
PANC...Northerly winds will increase through the day and into
Thursday morning. A brief period of light freezing rain is
possible after noon (21z) as an initial push of moisture moves
across the terminal. Confidence in this, however, is low given the
very dry air at the surface. It is possible that this round of
moisture does not make it to the ground and only drops ceilings to
around 5,000ft or so for a time. Given this, VFR conditions are
expected to persist until late Wednesday night / early Thursday
morning when a second band of freezing rain and/or snow develops,
producing MVFR conditions for the airport complex.
&&
.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...
The focus in the short term continues to be on the low and
associated front pushing north from the Gulf today, bringing
precipitation chances back to the area. Arctic high pressure over
central Alaska will maintain northeast winds and relatively cold
surface conditions. As the warm front and trailing warm air mass
push towards the coast, freezing rain will be possible for areas
around Cook Inlet today and especially tonight. Models continue
to vary somewhat with precipitation amounts so how much freezing
rain will occur is uncertain.
Farther east the cold air is deep enough in the Copper River
basin that precipitation should fall as all snow. Considerable
moisture will push over this cold air and produce advisory levels
of snowfall, with the highest amounts south of Tonsina.
Through Thompson Pass and Keystone Canyon blizzard conditions are
expected into early Thursday afternoon. A strong surface pressure
gradient will keep northeast winds in the 30 to 40 mph range,
combining with heavy snow to bring whiteout conditions.
The trailing occluded front will lift north on Thursday.
Precipitation chances will diminish across most of the area, but
snow accumulation is still expected in the Copper River Basin and
northern Susitna valley into the afternoon.
&&
.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2)...
A front has moved in over southwest Alaska from a low south of the
Alaska Peninsula. It is stalling over the Bristol Bay area and is
bringing rain to most areas near the water. Inland locations are
primarily seeing snow with a chance of light freezing rain mixing
in. These conditions will last through much of the night before
precipitation spreads to areas throughout southwest Alaska
Thursday. With the position of the low, northeast winds are
expected across the area which will also bring colder air.
Additionally, winds over the Kuskokwim Delta will be gusty,
seeing gusts to around 45 MPH through today before diminishing
Thursday. The colder temps moving in will mean that most any
precipitation to fall on Thursday will be snow.
&&
.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
The deep low south of the Alaska Peninsula will continue to track
east which will bring rain showers to the eastern Aleutians and
Alaska Peninsula. As the low pushes east, winds will switch from
the east to the north and cold air will be advected in on
Thursday. The colder air will drop Thursday night temps into the
lower 30s transitioning the rain showers over to snow. Out west,
northerly flow and light rain showers will dominate through
Thursday with the western Aleutians being cold enough overnight to
see a mix of rain and snow.
&&
.MARINE (Days 3 through 5/Friday through Sunday)...
There is potential for a small area of gales with a weakening low
in the Gulf of Alaska as well as with a compact low in the
vicinity of the far western Aleutians on Friday. After this,
forecast uncertainty rises significantly as we move into a pattern
with fast moving storm systems, many of which will likely bring
gale to storm force winds. The first of these storms is expected
to arrive somewhere along the Aleutians and/or Bering Sea Saturday
night or Sunday.
&&
.LONG TERM FORECAST (Days 4 through 7/Saturday through Tuesday)...
Starting on Saturday, an upper level low will be positioned in
the vicinity of Bristol Bay and the Alaska Peninsula, with surface
lows tracking up into the Gulf of Alaska. This will bring rounds
of high winds and heavy precipitation to maritime areas and the
Gulf coast/Kodiak Island. Some precipitation could spread inland
to Southcentral and Southwest, with rain or snow depending on
location.
Attention will then shift to a strong jet stream, driving a long-
wave trough eastward across the North Pacific. Expect numerous
fast moving deep storm systems to rapidly form and move through
the trough, affecting the Bering Sea/Aleutians beginning Saturday
night or Sunday and continuing through at least early next week -
and possibly longer. Model guidance is all over the place with
depictions of individual storm systems, but in general agreement
on the storm track which will be close the Aleutian chain. The
first of these storms will begin to impact the southern mainland
of Alaska by early next week. Expect high winds/seas and heavy
precipitation with each storm. It looks like there will be enough
arctic air over the southern mainland to support mostly snow
inland, with rain likely along the coast. Of course, individual
storm tracks will greatly affect this. Bottom line, the extended
forecast period will be characterized by an active storm pattern
with widespread weather impacts likely across the entire region.
&&
.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Winter Storm Watch 101 111 121.
Blizzard Warning 131.
Winter Weather Advisory 141.
MARINE...Gale Warning 119 120 130 131 155 173 174 176 180 181 185
414.
Heavy Freezing Spray 180.
FIRE WEATHER...NONE.
&&
SYNOPSIS AND MODEL DISCUSSION...TM
SOUTHCENTRAL ALASKA...BL
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...DK
MARINE/LONG TERM...SEB1 blizzard, 1 ice storm, 1 winter weather, 1 winter storm. Local standard time, as filed.
Alaska Department of Transportation confirmed 6 to 10 inches of new snow through Thompson Pass. RWIS site at Thompson Pass indicated winds gusting to 35 mph.
An NWS Employee in Big Lake reported 0.25 of ice accumulation.
Reports of accidents, cars and buses sliding off the road from social media. Anchorage School District cancelled afternoon activities. Several ASOS/AWOS sites across the area reported freezing rain.
An NWS employee reported 0.25 of ice accumulation in Soldotna, while another former employee reported 2 of snow in Kenai.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Alaska in 2019Every state in 2019This day in weather historyWarnings in Alaska, November 2019
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 861915, 861918, 861916, 861917.