February 2019 Weather in the Pacific Northwest - Part 1

[bainbridgekid]

Snow caked at the 112th exit in Everett. Down to 32° from 33° per the car thermometer.

I live off 112th about a mile West of the freeway. Getting close to 2" here now and it just started sticking to the roads here in the last 10 minutes!

[dairyd]

This is a done deal for the Seattle area... tomorrow morning is going to be crazy around here.    Freeways will be a mess.  

 

they could use this thing called salt....

[HighlandExperience]

This is a done deal for the Seattle area... tomorrow morning is going to be crazy around here.    Freeways will be a mess.  

 

Hope so. I want gridlock of ice. No work =)

[Perturbed Member]

Langley radar looks like the energy is sagging south. Hrrr has also been consistent with snow in the valley from about 10pm to 5-6am.

 

3KM NAM and HRRR both more or less agree on this, claiming all snow by midnight from an organized band. 

 

 

Temps initially a bit warm but drop to freezing overnight.

 

Pretty similar results to the 3km NAM on the snowfall map as well. 

 

 

I think there will be plenty of snow in the air overnight but am skeptical of the snow accumulation given that the euro and GFS basically give us nothing now. 

[seattleweatherguy]

Nws claims not enough moisture

[MikeInEverett]

https://youtu.be/rIoqwOe6KbA

 

This is what tomorrow morning may look like for Seattle.

[Prairiedog]

AFD for Portland for Wed thru the rest of the week.  Interesting.  I'm sure they're not taking a bite of the apple yet l because of model uncertainty.  I think the precip amts might align but the temps seem a bit conservative?.  Friday the models do look to bump freezing levels up but its beyond that I want to see what they have to say. 

Long term...Wednesday night through Sunday...models continue to
show another series of upper level disturbances dropping south out
of the Gulf of Alaska late next week. Unfortunately, there remains
considerable uncertainty with the track and timing of these systems,
with ensemble guidance showing a wide range of possibilities. As of
now, the general consensus is to bring a slug of moisture across the
region on Thursday, with additional shots of moisture through most
of the weekend. The good news is that snow levels over much of our
area look to generally rise above 1000 ft by Friday so the threat of
low elevation snow late next week and over the weekend looks minimal
at the moment, but this will all depend on how much cold air filters
down into our forecast area. All in all, expect somewhat seasonable
weather through next weekend

[seattleweatherguy]

Current Version Previous Version: 1 2 3 4 5

AREA FORECAST DISCUSSION

 

FXUS66 KSEW 040046

AFDSEW

 

Area Forecast Discussion

National Weather Service Seattle WA

446 PM PST Sun Feb 3 2019

 

.SYNOPSIS...Cold air will continue to spill out of British

Columbia through Monday while an upper level low moves southward

offshore. This combination will give most of the area snow

showers through at least Monday morning. Dry but cool weather is

expected Tuesday and Wednesday. Another round of cold and

unsettled weather is expected Thursday through next weekend.

 

&&

 

.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...Just a little busy here

at NWS Seattle this afternoon.

 

Doppler radar shows broad area of convergence from King county

into Whatcom county. Satellite imagery shows upper level low over

the northern tip of Vancouver Island with shower bands rotating

around the low off the coast. Doppler radar has the first of these

bands just offshore at 00z/4 pm. Temperatures at 4 pm were in the

30s.

 

Here is the current thinking on the snow forecast. Convergence

area, which did not form because of the cold air moving out of

British Columbia but because of the westerlies through the Strait

earlier today combined with southerly up the Puget Sound and the

cold air aloft, will diminish this evening with the flow through

the Strait going easterly. There still will be an area of

convergence as the cold air spills out of British Columbia but

this area will not cover near as much area as the current

convergence. Have a winter weather advisory for another inch of

snow in Snohomish, Skagit and Whatcom counties this evening with

the convergence. Next up the shower band currently offshore moving

inland over the southern portion of the area tonight.

Temperatures are currently just above freezing but dew points are

below freezing so once the precipitation begins temperatures will

fall and the precipitation type will change from rain to snow

this evening. Precipitation amounts to not look very heavy 0.20

inches or less overnight into early Monday morning. Have issued a

snow advisory for the central Coast, Lower Chehalis valley and

Southwest Interior for up to two inches of snow through early

Monday morning. Snow advisory also up for the Eastern Strait of

Juan de Fuca and the Admiralty Inlet area with some upslope flow

into the northern slopes of the Olympics enhancing the

precipitation rates later tonight into Monday morning.

 

So where does this leave the metro area??? Once the convergence

lifts north this evening there will be a little break in the

precipitation over the central Puget Sound area. Temperatures in

the metro area are currently in the lower to mid 30s.

Precipitation rates are light and the temperatures are marginal.

While there will be snow in the air for the evening hours with

the light precipitation rates only going to forecast up to an

inch overnight into early Monday morning.

 

Monday morning, most of the models are still developing a

deformation zone somewhere over the central and southern portion

of the interior Monday morning. As previously mentioned it is hard

to pin down the exact location and intensity of this feature with

much lead time. A couple of model trends are a little worrisome

about the development of this feature, one the upper level low

southward movement is slower than the models have predicted which

means two the cold air is still somewhat bottled up to the north.

Less low level convergence will result in lower precipitation

amounts if the deformation zone forms. For this forecast package

will have a possible addition up to an inch of snow accumulation

over the central interior including the Puget Sound region in the

4 am to 10 am window. Outside of the deformation zone showers

will still be rotating around the low with the best chances for

accumulating snow over the southern portion of the area. With

another inch or so of accumulation possible the snow advisory for

the Southwest Interior will continue until 1 pm. Upslope flow into

the northern slopes of the Olympics will also continue through

the morning hours will another 1 to 2 inches of snow possible

along the Eastern Strait of Juan de Fuca keeping the winter

weather advisory going there until 1 pm as well.

 

Monday afternoon, upper level low moving slowly south offshore

pulling the moisture with it south of the area. With the low

moving a little slower than the model forecasts have extended the

chance for snow showers from about Skagit county southward into

the early afternoon hours. By late afternoon the snow shower

chances will be confined to the southeast portion of the area.

Highs on Monday will be cool, only in the 30s with some places

near the Canadian border remaining in the 20s.

 

Drying trend Monday night as the low continues to move south with

a sunny but cool day expected on Tuesday. With the clearing skies

the cooler locations will fall into the teens Monday night. Highs

on Tuesday will be in the 30s and lower 40s.

 

Here is the current thinking on the wind. High wind warning still

in effect for San Juan as well as Western Whatcom and Skagit

counties beginning this evening and continuing into Monday night.

Cold air a little behind schedule but the winds at Ferndale are up

to 20 mph gusting to 40 mph at 4 pm. Winds will continue to

increase over the Northwest interior overnight as the Bellingham

to Williams Lake gradient becoming more negative as the much

colder air over British Columbia cools even more overnight ( the

temperature at Williams Lake at 4 pm was 11 below zero ). The

forecast of northeast winds 25 to 45 mph with gusts as high as 55

mph through Monday night remains intact.

 

.LONG TERM /THURSDAY THROUGH SUNDAY/...Little change in the

extended forecast this afternoon. Models continuing with the idea

of another cool upper level low moving down close to the area

toward the end of the week with another round of low snow levels.

Timing of the feature still inconsistent among the models so will

continue with the broad brush idea of chance pops through the

period with below normal temperatures. Felton

 

&&

 

.AVIATION...An upper low southwest of Vancouver Island will drop

southward over the offshore waters tonight and into the

Oregon waters on Monday. Southwesterly flow aloft will become

southeasterly Monday morning. At low levels, strong

northeast to north flow will gradually spread southward across the

region through early Monday as low pressure passes

by to the west and southwest and high pressure remains over

the interior of British Columbia. The air mass will be moist and

somewhat stable through Monday morning. Low MVFR and areas of IFR

ceilings in snow showers are expected through Monday. VFR

ceilings could develop across the far north portion of the area

early Monday as dry, colder air filters into the region. Ceilings

will improve to VFR over the Puget Sound area Monday afternoon.

 

 

KSEA...MVFR with periods of IFR persisting tonight into Monday AM.

Snow showers developing...with accumulations of 1-2 inches at

the terminal most likely occurring between 05Z and 15Z. Some

improvement in ceilings expected Monday afternoon as drier air

filters into the area. Surface winds shifting to northerly 01Z-03Z

and rising to 10 to 15 gusting 20 to 25 knots toward 12Z Monday. 27

 

&&

 

.MARINE...Flow will turn strongly offshore late today as a surface

low moves south over the offshore waters and a surface ridge

strengthens over the interior of British Columbia. Fraser outflow

will continue through Monday night. Gale force wind over the

northern inland waters this evening will spread to the Strait of

Juan de Fuca and adjacent coastal waters late tonight. Small craft

advisory strength winds will occur across the remainder of the

inland waters. Winds will ease on Tuesday as the outflow weakens. 27

 

.HYDROLOGY...River flooding not expected in the next 7 days.

 

&&

 

.SEW WATCHES/WARNINGS/ADVISORIES...

WA...Winter Weather Advisory until 1 PM PST Monday for Lower Chehalis

Valley Area-Southwest Interior.

 

High Wind Warning from 7 PM this evening to 4 AM PST Tuesday for

San Juan County-Western Skagit County-Western Whatcom

County.

 

Winter Weather Advisory until 10 PM PST this evening for Everett

and Vicinity-Western Skagit County-Western Whatcom County.

 

Winter Weather Advisory until 6 AM PST Monday for Central Coast.

 

Winter Weather Advisory from 10 PM this evening to 1 PM PST

Monday for Admiralty Inlet Area-Eastern Strait of Juan de

Fuca-Western Strait of Juan De Fuca.

 

PZ...Small Craft Advisory until 4 PM PST Monday for Admiralty Inlet-

Coastal Waters From James Island To Point Grenville Out 10

Nm-Coastal Waters From Point Grenville To Cape Shoalwater

Out 10 Nm.

 

Gale Warning until 4 PM PST Monday for Central U.S. Waters

Strait Of Juan De Fuca-Coastal Waters From Cape Flattery To

James Island 10 To 60 Nm-Coastal Waters From Cape Flattery

To James Island Out 10 Nm-Coastal Waters From James Island

To Point Grenville 10 To 60 Nm-Coastal Waters From Point

Grenville To Cape Shoalwater 10 To 60 Nm-East Entrance U.S.

Waters Strait Of Juan De Fuca-West Entrance U.S. Waters

Strait Of Juan De Fuca.

 

Gale Warning until 4 AM PST Tuesday for Northern Inland Waters

Including The San Juan Islands.

 

Small Craft Advisory from 10 PM this evening to 4 PM PST Monday

for Puget Sound and Hood Canal.

 

&&

 

 

 

 

www.weather.gov/seattle

[Deweydog]

Current Version Previous Version: 1 2 3 4 5

AREA FORECAST DISCUSSION

 

FXUS66 KSEW 040046

AFDSEW

 

Area Forecast Discussion

National Weather Service Seattle WA

446 PM PST Sun Feb 3 2019

 

.SYNOPSIS...Cold air will continue to spill out of British

Columbia through Monday while an upper level low moves southward

offshore. This combination will give most of the area snow

showers through at least Monday morning. Dry but cool weather is

expected Tuesday and Wednesday. Another round of cold and

unsettled weather is expected Thursday through next weekend.

 

&&

 

.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...Just a little busy here

at NWS Seattle this afternoon.

 

Doppler radar shows broad area of convergence from King county

into Whatcom county. Satellite imagery shows upper level low over

the northern tip of Vancouver Island with shower bands rotating

around the low off the coast. Doppler radar has the first of these

bands just offshore at 00z/4 pm. Temperatures at 4 pm were in the

30s.

 

Here is the current thinking on the snow forecast. Convergence

area, which did not form because of the cold air moving out of

British Columbia but because of the westerlies through the Strait

earlier today combined with southerly up the Puget Sound and the

cold air aloft, will diminish this evening with the flow through

the Strait going easterly. There still will be an area of

convergence as the cold air spills out of British Columbia but

this area will not cover near as much area as the current

convergence. Have a winter weather advisory for another inch of

snow in Snohomish, Skagit and Whatcom counties this evening with

the convergence. Next up the shower band currently offshore moving

inland over the southern portion of the area tonight.

Temperatures are currently just above freezing but dew points are

below freezing so once the precipitation begins temperatures will

fall and the precipitation type will change from rain to snow

this evening. Precipitation amounts to not look very heavy 0.20

inches or less overnight into early Monday morning. Have issued a

snow advisory for the central Coast, Lower Chehalis valley and

Southwest Interior for up to two inches of snow through early

Monday morning. Snow advisory also up for the Eastern Strait of

Juan de Fuca and the Admiralty Inlet area with some upslope flow

into the northern slopes of the Olympics enhancing the

precipitation rates later tonight into Monday morning.

 

So where does this leave the metro area??? Once the convergence

lifts north this evening there will be a little break in the

precipitation over the central Puget Sound area. Temperatures in

the metro area are currently in the lower to mid 30s.

Precipitation rates are light and the temperatures are marginal.

While there will be snow in the air for the evening hours with

the light precipitation rates only going to forecast up to an

inch overnight into early Monday morning.

 

Monday morning, most of the models are still developing a

deformation zone somewhere over the central and southern portion

of the interior Monday morning. As previously mentioned it is hard

to pin down the exact location and intensity of this feature with

much lead time. A couple of model trends are a little worrisome

about the development of this feature, one the upper level low

southward movement is slower than the models have predicted which

means two the cold air is still somewhat bottled up to the north.

Less low level convergence will result in lower precipitation

amounts if the deformation zone forms. For this forecast package

will have a possible addition up to an inch of snow accumulation

over the central interior including the Puget Sound region in the

4 am to 10 am window. Outside of the deformation zone showers

will still be rotating around the low with the best chances for

accumulating snow over the southern portion of the area. With

another inch or so of accumulation possible the snow advisory for

the Southwest Interior will continue until 1 pm. Upslope flow into

the northern slopes of the Olympics will also continue through

the morning hours will another 1 to 2 inches of snow possible

along the Eastern Strait of Juan de Fuca keeping the winter

weather advisory going there until 1 pm as well.

 

Monday afternoon, upper level low moving slowly south offshore

pulling the moisture with it south of the area. With the low

moving a little slower than the model forecasts have extended the

chance for snow showers from about Skagit county southward into

the early afternoon hours. By late afternoon the snow shower

chances will be confined to the southeast portion of the area.

Highs on Monday will be cool, only in the 30s with some places

near the Canadian border remaining in the 20s.

 

Drying trend Monday night as the low continues to move south with

a sunny but cool day expected on Tuesday. With the clearing skies

the cooler locations will fall into the teens Monday night. Highs

on Tuesday will be in the 30s and lower 40s.

 

Here is the current thinking on the wind. High wind warning still

in effect for San Juan as well as Western Whatcom and Skagit

counties beginning this evening and continuing into Monday night.

Cold air a little behind schedule but the winds at Ferndale are up

to 20 mph gusting to 40 mph at 4 pm. Winds will continue to

increase over the Northwest interior overnight as the Bellingham

to Williams Lake gradient becoming more negative as the much

colder air over British Columbia cools even more overnight ( the

temperature at Williams Lake at 4 pm was 11 below zero ). The

forecast of northeast winds 25 to 45 mph with gusts as high as 55

mph through Monday night remains intact.

 

.LONG TERM /THURSDAY THROUGH SUNDAY/...Little change in the

extended forecast this afternoon. Models continuing with the idea

of another cool upper level low moving down close to the area

toward the end of the week with another round of low snow levels.

Timing of the feature still inconsistent among the models so will

continue with the broad brush idea of chance pops through the

period with below normal temperatures. Felton

 

&&

 

.AVIATION...An upper low southwest of Vancouver Island will drop

southward over the offshore waters tonight and into the

Oregon waters on Monday. Southwesterly flow aloft will become

southeasterly Monday morning. At low levels, strong

northeast to north flow will gradually spread southward across the

region through early Monday as low pressure passes

by to the west and southwest and high pressure remains over

the interior of British Columbia. The air mass will be moist and

somewhat stable through Monday morning. Low MVFR and areas of IFR

ceilings in snow showers are expected through Monday. VFR

ceilings could develop across the far north portion of the area

early Monday as dry, colder air filters into the region. Ceilings

will improve to VFR over the Puget Sound area Monday afternoon.

 

 

KSEA...MVFR with periods of IFR persisting tonight into Monday AM.

Snow showers developing...with accumulations of 1-2 inches at

the terminal most likely occurring between 05Z and 15Z. Some

improvement in ceilings expected Monday afternoon as drier air

filters into the area. Surface winds shifting to northerly 01Z-03Z

and rising to 10 to 15 gusting 20 to 25 knots toward 12Z Monday. 27

 

&&

 

.MARINE...Flow will turn strongly offshore late today as a surface

low moves south over the offshore waters and a surface ridge

strengthens over the interior of British Columbia. Fraser outflow

will continue through Monday night. Gale force wind over the

northern inland waters this evening will spread to the Strait of

Juan de Fuca and adjacent coastal waters late tonight. Small craft

advisory strength winds will occur across the remainder of the

inland waters. Winds will ease on Tuesday as the outflow weakens. 27

 

.HYDROLOGY...River flooding not expected in the next 7 days.

 

&&

 

.SEW WATCHES/WARNINGS/ADVISORIES...

WA...Winter Weather Advisory until 1 PM PST Monday for Lower Chehalis

Valley Area-Southwest Interior.

 

High Wind Warning from 7 PM this evening to 4 AM PST Tuesday for

San Juan County-Western Skagit County-Western Whatcom

County.

 

Winter Weather Advisory until 10 PM PST this evening for Everett

and Vicinity-Western Skagit County-Western Whatcom County.

 

Winter Weather Advisory until 6 AM PST Monday for Central Coast.

 

Winter Weather Advisory from 10 PM this evening to 1 PM PST

Monday for Admiralty Inlet Area-Eastern Strait of Juan de

Fuca-Western Strait of Juan De Fuca.

 

PZ...Small Craft Advisory until 4 PM PST Monday for Admiralty Inlet-

Coastal Waters From James Island To Point Grenville Out 10

Nm-Coastal Waters From Point Grenville To Cape Shoalwater

Out 10 Nm.

 

Gale Warning until 4 PM PST Monday for Central U.S. Waters

Strait Of Juan De Fuca-Coastal Waters From Cape Flattery To

James Island 10 To 60 Nm-Coastal Waters From Cape Flattery

To James Island Out 10 Nm-Coastal Waters From James Island

To Point Grenville 10 To 60 Nm-Coastal Waters From Point

Grenville To Cape Shoalwater 10 To 60 Nm-East Entrance U.S.

Waters Strait Of Juan De Fuca-West Entrance U.S. Waters

Strait Of Juan De Fuca.

 

Gale Warning until 4 AM PST Tuesday for Northern Inland Waters

Including The San Juan Islands.

 

Small Craft Advisory from 10 PM this evening to 4 PM PST Monday

for Puget Sound and Hood Canal.

 

&&

 

 

 

 

www.weather.gov/seattle

Sounds good.

[HighlandExperience]

Seattle NWS discussion is pretty boring. 1-2 inches mmm 

[Requiem]

Current Version Previous Version: 1 2 3 4 5

AREA FORECAST DISCUSSION

 

FXUS66 KSEW 040046

AFDSEW

 

Area Forecast Discussion

National Weather Service Seattle WA

446 PM PST Sun Feb 3 2019

 

.SYNOPSIS...Cold air will continue to spill out of British

Columbia through Monday while an upper level low moves southward

offshore. This combination will give most of the area snow

showers through at least Monday morning. Dry but cool weather is

expected Tuesday and Wednesday. Another round of cold and

unsettled weather is expected Thursday through next weekend.

 

&&

 

.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...Just a little busy here

at NWS Seattle this afternoon.

 

Doppler radar shows broad area of convergence from King county

into Whatcom county. Satellite imagery shows upper level low over

the northern tip of Vancouver Island with shower bands rotating

around the low off the coast. Doppler radar has the first of these

bands just offshore at 00z/4 pm. Temperatures at 4 pm were in the

30s.

 

Here is the current thinking on the snow forecast. Convergence

area, which did not form because of the cold air moving out of

British Columbia but because of the westerlies through the Strait

earlier today combined with southerly up the Puget Sound and the

cold air aloft, will diminish this evening with the flow through

the Strait going easterly. There still will be an area of

convergence as the cold air spills out of British Columbia but

this area will not cover near as much area as the current

convergence. Have a winter weather advisory for another inch of

snow in Snohomish, Skagit and Whatcom counties this evening with

the convergence. Next up the shower band currently offshore moving

inland over the southern portion of the area tonight.

Temperatures are currently just above freezing but dew points are

below freezing so once the precipitation begins temperatures will

fall and the precipitation type will change from rain to snow

this evening. Precipitation amounts to not look very heavy 0.20

inches or less overnight into early Monday morning. Have issued a

snow advisory for the central Coast, Lower Chehalis valley and

Southwest Interior for up to two inches of snow through early

Monday morning. Snow advisory also up for the Eastern Strait of

Juan de Fuca and the Admiralty Inlet area with some upslope flow

into the northern slopes of the Olympics enhancing the

precipitation rates later tonight into Monday morning.

 

So where does this leave the metro area??? Once the convergence

lifts north this evening there will be a little break in the

precipitation over the central Puget Sound area. Temperatures in

the metro area are currently in the lower to mid 30s.

Precipitation rates are light and the temperatures are marginal.

While there will be snow in the air for the evening hours with

the light precipitation rates only going to forecast up to an

inch overnight into early Monday morning.

 

Monday morning, most of the models are still developing a

deformation zone somewhere over the central and southern portion

of the interior Monday morning. As previously mentioned it is hard

to pin down the exact location and intensity of this feature with

much lead time. A couple of model trends are a little worrisome

about the development of this feature, one the upper level low

southward movement is slower than the models have predicted which

means two the cold air is still somewhat bottled up to the north.

Less low level convergence will result in lower precipitation

amounts if the deformation zone forms. For this forecast package

will have a possible addition up to an inch of snow accumulation

over the central interior including the Puget Sound region in the

4 am to 10 am window. Outside of the deformation zone showers

will still be rotating around the low with the best chances for

accumulating snow over the southern portion of the area. With

another inch or so of accumulation possible the snow advisory for

the Southwest Interior will continue until 1 pm. Upslope flow into

the northern slopes of the Olympics will also continue through

the morning hours will another 1 to 2 inches of snow possible

along the Eastern Strait of Juan de Fuca keeping the winter

weather advisory going there until 1 pm as well.

 

Monday afternoon, upper level low moving slowly south offshore

pulling the moisture with it south of the area. With the low

moving a little slower than the model forecasts have extended the

chance for snow showers from about Skagit county southward into

the early afternoon hours. By late afternoon the snow shower

chances will be confined to the southeast portion of the area.

Highs on Monday will be cool, only in the 30s with some places

near the Canadian border remaining in the 20s.

 

Drying trend Monday night as the low continues to move south with

a sunny but cool day expected on Tuesday. With the clearing skies

the cooler locations will fall into the teens Monday night. Highs

on Tuesday will be in the 30s and lower 40s.

 

Here is the current thinking on the wind. High wind warning still

in effect for San Juan as well as Western Whatcom and Skagit

counties beginning this evening and continuing into Monday night.

Cold air a little behind schedule but the winds at Ferndale are up

to 20 mph gusting to 40 mph at 4 pm. Winds will continue to

increase over the Northwest interior overnight as the Bellingham

to Williams Lake gradient becoming more negative as the much

colder air over British Columbia cools even more overnight ( the

temperature at Williams Lake at 4 pm was 11 below zero ). The

forecast of northeast winds 25 to 45 mph with gusts as high as 55

mph through Monday night remains intact.

 

.LONG TERM /THURSDAY THROUGH SUNDAY/...Little change in the

extended forecast this afternoon. Models continuing with the idea

of another cool upper level low moving down close to the area

toward the end of the week with another round of low snow levels.

Timing of the feature still inconsistent among the models so will

continue with the broad brush idea of chance pops through the

period with below normal temperatures. Felton

 

&&

 

.AVIATION...An upper low southwest of Vancouver Island will drop

southward over the offshore waters tonight and into the

Oregon waters on Monday. Southwesterly flow aloft will become

southeasterly Monday morning. At low levels, strong

northeast to north flow will gradually spread southward across the

region through early Monday as low pressure passes

by to the west and southwest and high pressure remains over

the interior of British Columbia. The air mass will be moist and

somewhat stable through Monday morning. Low MVFR and areas of IFR

ceilings in snow showers are expected through Monday. VFR

ceilings could develop across the far north portion of the area

early Monday as dry, colder air filters into the region. Ceilings

will improve to VFR over the Puget Sound area Monday afternoon.

 

 

KSEA...MVFR with periods of IFR persisting tonight into Monday AM.

Snow showers developing...with accumulations of 1-2 inches at

the terminal most likely occurring between 05Z and 15Z. Some

improvement in ceilings expected Monday afternoon as drier air

filters into the area. Surface winds shifting to northerly 01Z-03Z

and rising to 10 to 15 gusting 20 to 25 knots toward 12Z Monday. 27

 

&&

 

.MARINE...Flow will turn strongly offshore late today as a surface

low moves south over the offshore waters and a surface ridge

strengthens over the interior of British Columbia. Fraser outflow

will continue through Monday night. Gale force wind over the

northern inland waters this evening will spread to the Strait of

Juan de Fuca and adjacent coastal waters late tonight. Small craft

advisory strength winds will occur across the remainder of the

inland waters. Winds will ease on Tuesday as the outflow weakens. 27

 

.HYDROLOGY...River flooding not expected in the next 7 days.

 

&&

 

.SEW WATCHES/WARNINGS/ADVISORIES...

WA...Winter Weather Advisory until 1 PM PST Monday for Lower Chehalis

Valley Area-Southwest Interior.

 

High Wind Warning from 7 PM this evening to 4 AM PST Tuesday for

San Juan County-Western Skagit County-Western Whatcom

County.

 

Winter Weather Advisory until 10 PM PST this evening for Everett

and Vicinity-Western Skagit County-Western Whatcom County.

 

Winter Weather Advisory until 6 AM PST Monday for Central Coast.

 

Winter Weather Advisory from 10 PM this evening to 1 PM PST

Monday for Admiralty Inlet Area-Eastern Strait of Juan de

Fuca-Western Strait of Juan De Fuca.

 

PZ...Small Craft Advisory until 4 PM PST Monday for Admiralty Inlet-

Coastal Waters From James Island To Point Grenville Out 10

Nm-Coastal Waters From Point Grenville To Cape Shoalwater

Out 10 Nm.

 

Gale Warning until 4 PM PST Monday for Central U.S. Waters

Strait Of Juan De Fuca-Coastal Waters From Cape Flattery To

James Island 10 To 60 Nm-Coastal Waters From Cape Flattery

To James Island Out 10 Nm-Coastal Waters From James Island

To Point Grenville 10 To 60 Nm-Coastal Waters From Point

Grenville To Cape Shoalwater 10 To 60 Nm-East Entrance U.S.

Waters Strait Of Juan De Fuca-West Entrance U.S. Waters

Strait Of Juan De Fuca.

 

Gale Warning until 4 AM PST Tuesday for Northern Inland Waters

Including The San Juan Islands.

 

Small Craft Advisory from 10 PM this evening to 4 PM PST Monday

for Puget Sound and Hood Canal.

 

&&

 

 

 

 

www.weather.gov/seattle

 

Sounds great!

[TT-SEA]

Dead calm here...

 

[umadbro]

Must we copy and paste an AFD and then quote that post multiple times?

[Deweydog]

Snowing at my mommy and daddy’s house!!!

[Timmy]

Current Version Previous Version: 1 2 3 4 5

AREA FORECAST DISCUSSION

FXUS66 KSEW 040046

AFDSEW

Area Forecast Discussion

National Weather Service Seattle WA

446 PM PST Sun Feb 3 2019

.SYNOPSIS...Cold air will continue to spill out of British

Columbia through Monday while an upper level low moves southward

offshore. This combination will give most of the area snow

showers through at least Monday morning. Dry but cool weather is

expected Tuesday and Wednesday. Another round of cold and

unsettled weather is expected Thursday through next weekend.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...Just a little busy here

at NWS Seattle this afternoon.

Doppler radar shows broad area of convergence from King county

into Whatcom county. Satellite imagery shows upper level low over

the northern tip of Vancouver Island with shower bands rotating

around the low off the coast. Doppler radar has the first of these

bands just offshore at 00z/4 pm. Temperatures at 4 pm were in the

30s.

Here is the current thinking on the snow forecast. Convergence

area, which did not form because of the cold air moving out of

British Columbia but because of the westerlies through the Strait

earlier today combined with southerly up the Puget Sound and the

cold air aloft, will diminish this evening with the flow through

the Strait going easterly. There still will be an area of

convergence as the cold air spills out of British Columbia but

this area will not cover near as much area as the current

convergence. Have a winter weather advisory for another inch of

snow in Snohomish, Skagit and Whatcom counties this evening with

the convergence. Next up the shower band currently offshore moving

inland over the southern portion of the area tonight.

Temperatures are currently just above freezing but dew points are

below freezing so once the precipitation begins temperatures will

fall and the precipitation type will change from rain to snow

this evening. Precipitation amounts to not look very heavy 0.20

inches or less overnight into early Monday morning. Have issued a

snow advisory for the central Coast, Lower Chehalis valley and

Southwest Interior for up to two inches of snow through early

Monday morning. Snow advisory also up for the Eastern Strait of

Juan de Fuca and the Admiralty Inlet area with some upslope flow

into the northern slopes of the Olympics enhancing the

precipitation rates later tonight into Monday morning.

So where does this leave the metro area??? Once the convergence

lifts north this evening there will be a little break in the

precipitation over the central Puget Sound area. Temperatures in

the metro area are currently in the lower to mid 30s.

Precipitation rates are light and the temperatures are marginal.

While there will be snow in the air for the evening hours with

the light precipitation rates only going to forecast up to an

inch overnight into early Monday morning.

Monday morning, most of the models are still developing a

deformation zone somewhere over the central and southern portion

of the interior Monday morning. As previously mentioned it is hard

to pin down the exact location and intensity of this feature with

much lead time. A couple of model trends are a little worrisome

about the development of this feature, one the upper level low

southward movement is slower than the models have predicted which

means two the cold air is still somewhat bottled up to the north.

Less low level convergence will result in lower precipitation

amounts if the deformation zone forms. For this forecast package

will have a possible addition up to an inch of snow accumulation

over the central interior including the Puget Sound region in the

4 am to 10 am window. Outside of the deformation zone showers

will still be rotating around the low with the best chances for

accumulating snow over the southern portion of the area. With

another inch or so of accumulation possible the snow advisory for

the Southwest Interior will continue until 1 pm. Upslope flow into

the northern slopes of the Olympics will also continue through

the morning hours will another 1 to 2 inches of snow possible

along the Eastern Strait of Juan de Fuca keeping the winter

weather advisory going there until 1 pm as well.

Monday afternoon, upper level low moving slowly south offshore

pulling the moisture with it south of the area. With the low

moving a little slower than the model forecasts have extended the

chance for snow showers from about Skagit county southward into

the early afternoon hours. By late afternoon the snow shower

chances will be confined to the southeast portion of the area.

Highs on Monday will be cool, only in the 30s with some places

near the Canadian border remaining in the 20s.

Drying trend Monday night as the low continues to move south with

a sunny but cool day expected on Tuesday. With the clearing skies

the cooler locations will fall into the teens Monday night. Highs

on Tuesday will be in the 30s and lower 40s.

Here is the current thinking on the wind. High wind warning still

in effect for San Juan as well as Western Whatcom and Skagit

counties beginning this evening and continuing into Monday night.

Cold air a little behind schedule but the winds at Ferndale are up

to 20 mph gusting to 40 mph at 4 pm. Winds will continue to

increase over the Northwest interior overnight as the Bellingham

to Williams Lake gradient becoming more negative as the much

colder air over British Columbia cools even more overnight ( the

temperature at Williams Lake at 4 pm was 11 below zero ). The

forecast of northeast winds 25 to 45 mph with gusts as high as 55

mph through Monday night remains intact.

.LONG TERM /THURSDAY THROUGH SUNDAY/...Little change in the

extended forecast this afternoon. Models continuing with the idea

of another cool upper level low moving down close to the area

toward the end of the week with another round of low snow levels.

Timing of the feature still inconsistent among the models so will

continue with the broad brush idea of chance pops through the

period with below normal temperatures. Felton

&&

.AVIATION...An upper low southwest of Vancouver Island will drop

southward over the offshore waters tonight and into the

Oregon waters on Monday. Southwesterly flow aloft will become

southeasterly Monday morning. At low levels, strong

northeast to north flow will gradually spread southward across the

region through early Monday as low pressure passes

by to the west and southwest and high pressure remains over

the interior of British Columbia. The air mass will be moist and

somewhat stable through Monday morning. Low MVFR and areas of IFR

ceilings in snow showers are expected through Monday. VFR

ceilings could develop across the far north portion of the area

early Monday as dry, colder air filters into the region. Ceilings

will improve to VFR over the Puget Sound area Monday afternoon.

KSEA...MVFR with periods of IFR persisting tonight into Monday AM.

Snow showers developing...with accumulations of 1-2 inches at

the terminal most likely occurring between 05Z and 15Z. Some

improvement in ceilings expected Monday afternoon as drier air

filters into the area. Surface winds shifting to northerly 01Z-03Z

and rising to 10 to 15 gusting 20 to 25 knots toward 12Z Monday. 27

&&

.MARINE...Flow will turn strongly offshore late today as a surface

low moves south over the offshore waters and a surface ridge

strengthens over the interior of British Columbia. Fraser outflow

will continue through Monday night. Gale force wind over the

northern inland waters this evening will spread to the Strait of

Juan de Fuca and adjacent coastal waters late tonight. Small craft

advisory strength winds will occur across the remainder of the

inland waters. Winds will ease on Tuesday as the outflow weakens. 27

.HYDROLOGY...River flooding not expected in the next 7 days.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...

WA...Winter Weather Advisory until 1 PM PST Monday for Lower Chehalis

Valley Area-Southwest Interior.

High Wind Warning from 7 PM this evening to 4 AM PST Tuesday for

San Juan County-Western Skagit County-Western Whatcom

County.

Winter Weather Advisory until 10 PM PST this evening for Everett

and Vicinity-Western Skagit County-Western Whatcom County.

Winter Weather Advisory until 6 AM PST Monday for Central Coast.

Winter Weather Advisory from 10 PM this evening to 1 PM PST

Monday for Admiralty Inlet Area-Eastern Strait of Juan de

Fuca-Western Strait of Juan De Fuca.

PZ...Small Craft Advisory until 4 PM PST Monday for Admiralty Inlet-

Coastal Waters From James Island To Point Grenville Out 10

Nm-Coastal Waters From Point Grenville To Cape Shoalwater

Out 10 Nm.

Gale Warning until 4 PM PST Monday for Central U.S. Waters

Strait Of Juan De Fuca-Coastal Waters From Cape Flattery To

James Island 10 To 60 Nm-Coastal Waters From Cape Flattery

To James Island Out 10 Nm-Coastal Waters From James Island

To Point Grenville 10 To 60 Nm-Coastal Waters From Point

Grenville To Cape Shoalwater 10 To 60 Nm-East Entrance U.S.

Waters Strait Of Juan De Fuca-West Entrance U.S. Waters

Strait Of Juan De Fuca.

Gale Warning until 4 AM PST Tuesday for Northern Inland Waters

Including The San Juan Islands.

Small Craft Advisory from 10 PM this evening to 4 PM PST Monday

for Puget Sound and Hood Canal.

&&

www.weather.gov/seattle

Agreed

[Blizzard777]

Northly flow has begun 35.5

Very light snow

[Perturbed Member]

PDX radar is back, some decent organized echos visible now. Showing up as snow over the coast range. 

[HighlandExperience]

Seems like the precipitation is not as heavy now,,, mmm. 

[FroYoBro]

Outflow really going at Bellingham now. DP down to 10.

[TigerWoodsLibido]

43 and cloudy.

[SilverFallsAndrew]

Sometimes I wonder if the NWS people even like weather...Not all of course I know some are huge nerds. For others I think it is just a job.

[Guest Sounder]

Cliff Mass should have known better. Pretty shocking mistake coming from him.

 

The error on the MM5 models was too much easterly gradient.

You'd think a stupid liberal like him would be more supportive of snowflakes!!!

[MikeInEverett]

Seems like the precipitation is not as heavy now,,, mmm.

Yep definitely looks like our current band is starting to die down. Hopefully we still score some more tonight.

[TT-SEA]

No problem sticking to road here..

 

[MR.SNOWMIZER]

I've never cared for Cliff Mass much and he's ugly.

[seattleweatherguy]

Nws basically saying nothing. Ouch what aren't I seeing

[TT-SEA]

Cliff Mass and Tim should go driving around tomorrow in the snow. With bald tires. Going way too fast.

 

 

Glad I got those new tires!   

[MossMan]

29.5 and light snow.

[Guest hawkstwelve]

Just had the most beautiful drive from Redmond to Carnation. Heavy or moderate snow the whole time with big, white, fluffy flakes and everything caked white.

 

The roads were fine until just off Hwy 202 on Tolt Hill when they got really snowy. Snoqualmie Valley is just starting to stick to roads and our hill is covered as well.

 

Unless precip quickly shuts off (doubt it) the NWS is going to get egg on their face with this. The Euro will end up right and I shouldn't have doubted.

[Timmy]

So I guess its a non event.

dunno, I didn’t read it

[El_Nina]

40 degrees and a little splattering in the rain. Temp has gone down 2 in the past 10

[umadbro]

Hrrr still sticking to its guns for the valley

[Guest hawkstwelve]

We have the 'owl index' for snowfall at our house and let me tell ya, he's starting to look a little cold.

 

Edit: I took this picture about 15 mins ago and it's now up to his face.

 

[TT-SEA]

Going on faith that the significant accumulations for King County that the 12Z ECMWF showed from 10 p.m. - 4 a.m. will indeed happen because the radar is looking less impressive right now.    

[TigerWoodsLibido]

[Requiem]

It's still 44 in Portland, I assume it is still going to cool down eventually.

[MossMan]

Snow really coming down again! 29.3 and breezy north wind.

[Deweydog]

We have the 'owl index' for snowfall at our house and let me tell ya, he's starting to look a little cold.

 

We used a bald mannequin head for that in February 2014.

[Deweydog]

It's still 44 in Portland, I assume it is still going to cool down eventually.

You know what assuming does...

[Esquimalt]

snow and ice pellet mix throughout the southern portions of Victoria. Light dusting on grassy surfaces