January 2016 in the PNW

[TT-SEA]

The WRF shows pretty good precip amounts up here early Monday, but gives no indication of any lowland snow.  With easterly winds freezing rain could be a strong possibility for areas of the East Puget Sound lowlands.  I don't mind it so much with rainfall amounts less than a third of an inch or so.  The WRF also indicate many places remaining below 40 for highs on Monday.

 

 

I have already accepted the fact that after 2 weeks of dealing with the kids at home... the schools will be closed on Monday due to freezing rain or snow.  Ironically, they will be home on the day that all the snow finally melts here.   

[BLI snowman]

I heard recently and repeatedly around here that Mark is all washed up. Pretty suspect forecast. Hope he's right.

 

It's a tad on the optimist side (I'd be surprised if anyone sees 3"), but in general I think he's right to catch onto the late cooling trend with the operational models. There's no question the operational GFS supports an inch or two across the entire area. Probably a decent chance that the trend is with good reason.

[FroYoBro]

Mark sure has a disgusting warm bias, huh Jesse? 

[TT-SEA]

ECMWF has precip all the way up here in the 1-4 p.m. period tomorrow.    Big change.

 

Heaviest precip in Portland is during the evening tomorrow on the ECMWF... and in Seattle all day on Monday.     Precip band completely stalls over Seattle on Monday and the flow is still offshore.

[HighlandExperience]

ECMWF has precip all the way up here in the 1-4 p.m. period tomorrow.    Big change.

 

Heaviest precip in Portland is during the evening tomorrow on the ECMWF... and in Seattle early Monday morning.

 

That is a nice change as long as we see snow. Snow Wiz time to break out those special maps =)

[Deweydog]

Euro is definitely a bit slower with the warming compared to the NAM, GFS, Canadian.

[TT-SEA]

That is a nice change as long as we see snow. Snow Wiz time to break out those special maps =)

 

 

I updated my post.  

 

ECMWF shows lots of precip over Seattle all day on Monday with temps in the 32-39 range.

[FroYoBro]

Snow or rain, tomorrow looks like it will be a mess out on the roads. Already down to 26 and I doubt I make it above freezing unless the moisture arrives later than expected. 

[TT-SEA]

Because the band hangs up over Seattle all day on Monday... the 00Z ECMWF now shows lowland snow that day as well.     

[TT-SEA]

HRRR total snow through 6 p.m. tomorrow.

 

http://rapidrefresh.noaa.gov/HRRR/for_web/hrrr_jet/2016010303/t1/acsnw_t1sfc_f23.png

[Deweydog]

Snow or rain, tomorrow looks like it will be a mess out on the roads. Already down to 26 and I doubt I make it above freezing unless the moisture arrives later than expected.

Indeed that's what actually matters. This will be a high impact event.

[TT-SEA]

Indeed that's what actually matters. This will be a high impact event.

 

 

Now thinking this will be an even higher impact for the Seattle area being that it hits before the morning commute on Monday.

[TT-SEA]

Dewpoint at SEA is 12.  

[Deweydog]

Dewpoint at SEA is 12.

Go Seahawks!

[Deweydog]

You can definitely see why the models trended wetter. The deformation setting up between the two features is very evident on the water vapor loop.

[BLI snowman]

You can definitely see why the models trended wetter. The deformation setting up between the two features is very evident on the water vapor loop.

 

And to think this mostly stems from the funky little ULL that originated in the Great Basin and magically made a beeline towards us.  

[Deweydog]

And to think this mostly stems from the funky little ULL that originated in the Great Basin and magically made a beeline towards us.

Pretty goofy . Good luck finding a decent analog.

[snow_wizard]

The 0z ECMWF is much wetter for the Seattle area late tomorrow night  / early Monday morning.  850s stay below zero until mid morning on Monday.  As a result it does show snow for us.  This snowfall map has been disappointing in its accuracy in the past.  A bit later the ECMWF WRF will be in and that is higher resolution.

[TT-SEA]

The 0z ECMWF is much wetter for the Seattle area late tomorrow night  / early Monday morning.  850s stay below zero until mid morning on Monday.  As a result it does show snow for us.  This snowfall map has been disappointing in its accuracy in the past.  A bit later the ECMWF WRF will be in and that is higher resolution.

 

 

I mentioned this above... with a flurry of positive comments.     I know its easier for you to say I dismiss all snow chances but that is just not true.   Not last week and not now... and not ever really.    

[HighlandExperience]

The 0z ECMWF is much wetter for the Seattle area late tomorrow night / early Monday morning. 850s stay below zero until mid morning on Monday. As a result it does show snow for us. This snowfall map has been disappointing in its accuracy in the past. A bit later the ECMWF WRF will be in and that is higher resolution.

That looks pretty nice.

[bainbridgekid]

Seatle AFD mentions snow Sunday night but confident in all rain on Monday.

 

This was before the Euro came out though.

 

INCREASING HIGH CLOUDS IN THE AFTERNOON WILL HERALD A RETURN TO MORE
SEASONAL TEMPERATURES AND CHANCES OF RAIN. RECENT MODEL TRENDS ARE
TO MAKE THE SYSTEM ARRIVING FROM THE SOUTH SUNDAY NIGHT A LITTLE
WETTER. MORE PRECIPITATION ACTUALLY INCREASES THE CHANCE THERE WILL
BE SOME SNOW AROUND THE BEGINNING OF THE EVENT. THE SNOW LEVEL WILL
BE BELOW 1000 FEET SUNDAY EVENING BEFORE RISING TO 2000-4000 FEET
12Z-18Z. PRECIPITATION WILL BE LIGHT BUT A FEW ZONES SUCH AS THE
HOOD CANAL AREA COULD GET A LITTLE SNOW. CURRENT FORECASTS CALL FOR
UP TO AN INCH IN SOME PLACES AND THAT IS FINE FOR NOW. AS ALWAYS IT
WILL BE HARD TO PRODUCE ANY SNOW IN THE SEATTLE METRO AREA.

ALL PRECIPITATION WILL BE RAIN ON MONDAY AS TEMPERATURES RISE INTO
THE MID 40S. ANOTHER IMPULSE FROM THE SOUTH WILL BRING A LITTLE MORE
RAIN ON TUESDAY AND TEMPERATURES WILL TAKE ANOTHER SMALL JUMP
UPWARD. BURKE

[stuffradio]

I'm happy for you folks down in Portland. I just want to see some snow in Seattle for a change. 

Same here, except I want to see some snow in Vancouver, BC and the surrounding cities for a change.

 

Edit: Man, that would be quite the overrunning event!

 

 

Wed, Jan 13 http://images.myforecast.com/images/my_forecast_icons/new_weather/small/snow_rain_mix.gif Snow changing to rain. Mostly cloudy. Cool. 6°C 0°C 12 km/h / E 87% 4°C Minimal 97% 21.43cm

http://www.myforecast.com/bin/expanded_forecast_15day.m?city=54215&metric=true

[Perturbed Member]

The PDX NWS needs to adjust their forecast for Portland metro pretty quickly, they are underplaying this quite a bit. Snow or not, there will be .2 to .4+ in QPF of frozen stuff coming in tomorrow in some form. They still seem to be under the impression that we will see some ZR drizzle around here. 

 

 

Mark Nelsen quite confident that PDX will be all snow at least for the first half of the precip: "During at least the first half of the event the atmosphere overhead should be cold enough to support snow all the way down. For sure that’s the case in the metro area; I’m less confident on pure snow from Salem south to Eugene (thinner cold layer above). "

 

Seems reasonable to me. 
 

 

He thinks PDX might be all snow as the models might be pushing the cold out too fast even aloft: "the rest of us in the metro area would stay in snow longer…possibly through the entire event.  Remember during the last east wind event in mid December that models eroded the cool air higher up too quickly…the precipitation stayed as snow longer than we expected.  That might be the case tomorrow."

[HighlandExperience]

The PDX NWS needs to adjust their forecast for Portland metro pretty quickly, they are underplaying this quite a bit. Snow or not, there will be .2 to .4+ in QPF of frozen stuff coming in tomorrow in some form. They still seem to be under the impression that we will see some ZR drizzle around here.

 

 

Mark Nelsen quite confident that PDX will be all snow at least for the first half of the precip: "During at least the first half of the event the atmosphere overhead should be cold enough to support snow all the way down. For sure that’s the case in the metro area; I’m less confident on pure snow from Salem south to Eugene (thinner cold layer above). "

 

Seems reasonable to me.

 

 

He thinks PDX might be all snow as the models might be pushing the cold out too fast even aloft: "the rest of us in the metro area would stay in snow longer…possibly through the entire event. Remember during the last east wind event in mid December that models eroded the cool air higher up too quickly…the precipitation stayed as snow longer than we expected. That might be the case tomorrow."

Considering their history they are just playing it safe.

[BLI snowman]

The PDX NWS needs to adjust their forecast for Portland metro pretty quickly, they are underplaying this quite a bit. Snow or not, there will be .2 to .4+ in QPF of frozen stuff coming in tomorrow in some form. They still seem to be under the impression that we will see some ZR drizzle around here. 

 

 

Mark Nelsen quite confident that PDX will be all snow at least for the first half of the precip: "During at least the first half of the event the atmosphere overhead should be cold enough to support snow all the way down. For sure that’s the case in the metro area; I’m less confident on pure snow from Salem south to Eugene (thinner cold layer above). "

 

Seems reasonable to me. 

 

 

He thinks PDX might be all snow as the models might be pushing the cold out too fast even aloft: "the rest of us in the metro area would stay in snow longer…possibly through the entire event.  Remember during the last east wind event in mid December that models eroded the cool air higher up too quickly…the precipitation stayed as snow longer than we expected.  That might be the case tomorrow."

 

Yeah, their 9pm discussion seemed to really emphasize the virga aspect in the Portland area which seems silly. All of the models presently show enough QPF to create issues tomorrow. Virga looks to be a pretty fleeting issue before the lower levels moisten up adequately. I think they're holding onto their bearishness as long as they possibly can, but a Winter Weather Advisory is definitely warranted.

[Gradient Keeper]

I am just throwing this out there, but these kind of deformation patterns can turn far wetter/snowier than expected. They have in the past.

[FroYoBro]

Yeah, their 9pm discussion seemed to really emphasize the virga aspect in the Portland area which seems silly. All of the models presently show enough QPF to create issues tomorrow. Virga looks to be a pretty fleeting issue before the lower levels moisten up adequately. I think they're holding onto their bearishness as long as they possibly can, but a Winter Weather Advisory is definitely warranted.

 

It seems like the NWS consistently does a pretty poor job predicting wintery events for Portland. This IS a very difficult area to predict snow, but they have had a lot of big busts on both sides of the coin in the last decade. 

[snow_wizard]

Seatle AFD mentions snow Sunday night but confident in all rain on Monday.

 

This was before the Euro came out though.

 

INCREASING HIGH CLOUDS IN THE AFTERNOON WILL HERALD A RETURN TO MORE

SEASONAL TEMPERATURES AND CHANCES OF RAIN. RECENT MODEL TRENDS ARE

TO MAKE THE SYSTEM ARRIVING FROM THE SOUTH SUNDAY NIGHT A LITTLE

WETTER. MORE PRECIPITATION ACTUALLY INCREASES THE CHANCE THERE WILL

BE SOME SNOW AROUND THE BEGINNING OF THE EVENT. THE SNOW LEVEL WILL

BE BELOW 1000 FEET SUNDAY EVENING BEFORE RISING TO 2000-4000 FEET

12Z-18Z. PRECIPITATION WILL BE LIGHT BUT A FEW ZONES SUCH AS THE

HOOD CANAL AREA COULD GET A LITTLE SNOW. CURRENT FORECASTS CALL FOR

UP TO AN INCH IN SOME PLACES AND THAT IS FINE FOR NOW. AS ALWAYS IT

WILL BE HARD TO PRODUCE ANY SNOW IN THE SEATTLE METRO AREA.

 

ALL PRECIPITATION WILL BE RAIN ON MONDAY AS TEMPERATURES RISE INTO

THE MID 40S. ANOTHER IMPULSE FROM THE SOUTH WILL BRING A LITTLE MORE

RAIN ON TUESDAY AND TEMPERATURES WILL TAKE ANOTHER SMALL JUMP

UPWARD. BURKE

 

I'm not sure what it means...as always it will be hard to produce snow in the Seattle metro area...

 

Kind of an inaccurate statement when you look at Dec 2008, Nov 2010, Jan 2012, etc, etc.

[Jesse]

What a day snowshoeing west of Bend. Ended up climbing Tumalo Mountain off the Cascade Lakes highway, across from Mount Bachelor. The temperature near the summit, in the afternoon, was 1F. Good thing we bundled up.

 

And now we're coming home to talk of snow tomorrow!

[snow_wizard]

I am just throwing this out there, but these kind of deformation patterns can turn far wetter/snowier than expected. They have in the past.

 

No doubt about that whatsoever.  The fact the models are trending wetter means it could end up even wetter than is currently being shown.  We have got a boatload of cold / dry in place over the area now.  With nothing but easterly winds slated into Monday how on Earth is it going to warm up much?

[MossMan]

might my area get in on any snow action? 24 degrees right now and the roads were extremely slick all around the north county area.

[SilverFallsAndrew]

All the spots in South Central and E. Oregon that got below -10 last night. 

[SilverFallsAndrew]

All the spots in South Central and E. Oregon that got below -10 last night. 

[SilverFallsAndrew]

Currently 22 degrees. I am not expecting much tomorrow. Maybe a dusting before the warm tongue noses in. Hope to be wrong.

[TT-SEA]

I am just throwing this out there, but these kind of deformation patterns can turn far wetter/snowier than expected. They have in the past.

 

 

Yeah... this whole event seems to have nothing but upside potential.     I remember events that were supposed to scour out fast and never did at all.    And this is an impressive cold pool set-up.     

 

Also we have the models trending wetter and slower which might also be related to the interaction with the cold air mass in place.   

[SilverFallsAndrew]

[SilverFallsAndrew]

I always say a general rule of thumb for PDX in a "cold pool" east wind type situation is that you want temps 28 or lower at The Dalles and 24 or lower at Pendleton. Currently mid 20s in the E. Gorge and 17 in Pendleton. Looks good to go. 

[FroYoBro]

I always say a general rule of thumb for PDX in a "cold pool" east wind type situation is that you want temps 28 or lower at The Dalles and 24 or lower at Pendleton. Currently mid 20s in the E. Gorge and 17 in Pendleton. Looks good to go. 

 

Yeah, low level temperatures will easily be cold enough. It is nice that we don't have to worry about that for a little while. 

[epiceast]

I think we had an event similar to this that dropped about a foot over Snoqualmie pass 3 years ago. The lowlands were just a tad too warm snow levels were somewhere between 500' and 1000'. The models didn't catch on to the massive precipitation until 24 hours before the event. I don't think it was caused by a ULL coming from great basin and tracking NNW, it was more of a typical ninoish ULL that got stuck in California and then somehow went north.

[Gradient Keeper]

I was right. 6z NAM has more QPF/Moisture .40" to .75" and 2-4" snow for PDX. As much as the past 3 runs have moistened that could continue... Snow storm anyone?