January 2017 Observations and Model Discussion for the Pacific Northwest

[Timmy Supercell]

The weenie in me is still bitter after seeing PDX score so epicly, which is why I haven't posted for several days.  Too many similarities to 2008, which caused me some Jim level disappointment.  But a thought occurred to me in that the gorge increases snowfall down here quite a bit.  In many occasions, the entire Willamette Valley fills with cold thanks to the gorge.  Without it, I'd be Roseburg.  It snows far less in Roseburg.

 

I am happy for the PDX forum members.

 

Since it's going to be 2008 again. June 2009 severe thunderstorm outbreak again? 

 

CFS - WHAT DOES IT SAY FOR 06/04? 

[Deweydog]

Turns out we do a lot better without major upper level airmasses. Who knew.

Imagine how cold we'd be right now with January 2009's +PNA parked over us!

 

Highs in the teens!

[Deweydog]

00z is running!!!

[Bryant]

00z is running!!!

May it bring LR goodies

[Dave]

Since it's going to be 2008 again. June 2009 severe thunderstorm outbreak again? 

 

Funny that you brought that up.  Yet another sad frog moment down here.

 

During that event, a very strong cell was headed straight for Eugene.  It split in two and both went around town and missed me completely.  Not even a lightning strike.  The western cell produced a tornado NW of town and the eastern cell produced hail nearly the size of golf balls.  I haven't seen a severe tstorm here since I was a kid.  

[SilverFallsAndrew]

Turns out we do a lot better without major upper level airmasses. Who knew.

 

Think about it. Eugene was hitting 40 a little over a week ago with solid snow cover and a cold upper level airmass and a starting point of 14. With this airmass and no snow they string together two straight sub freezing highs and a high of 35 today... Helps to have a little inversion going. 

[Timmy Supercell]

Funny that you brought that up.  Yet another sad frog moment down here.

 

During that event, a very strong cell was headed straight for Eugene.  It split in two and both went around town and missed me completely.  Not even a lightning strike.  The western cell produced a tornado NW of town and the eastern cell produced hail nearly the size of golf balls.  I haven't seen a severe tstorm here since I was a kid.  

 

That was my first time I've seen a shelf cloud. There was even a minor roll cloud under much of the lines. 

 

Unfortunately by the time I got the cloud porn the event was slowly unfolding near the Portland Metro. Haven't seen clouds like that though since 2009. 

[Dave]

Think about it. Eugene was hitting 40 a little over a week ago with solid snow cover and a cold upper level airmass and a starting point of 14. With this airmass and no snow they string together two straight sub freezing highs and a high of 35 today... Helps to have a little inversion going. 

I have at least a half inch of snow in the shady areas 

[BLI snowman]

Think about it. Eugene was hitting 40 a little over a week ago with solid snow cover and a cold upper level airmass and a starting point of 14. With this airmass and no snow they string together two straight sub freezing highs and a high of 35 today... Helps to have a little inversion going.

Inversions can last forever AFAIC when there's still 8" of snowcover.

[Deweydog]

Think about it. Eugene was hitting 40 a little over a week ago with solid snow cover and a cold upper level airmass and a starting point of 14. With this airmass and no snow they string together two straight sub freezing highs and a high of 35 today... Helps to have a little inversion going.

This is essentially how PDX achieved its ridiculousness late January/early February 1950. Or even Eugene in December 2013.

[Jesse]

Think about it. Eugene was hitting 40 a little over a week ago with solid snow cover and a cold upper level airmass and a starting point of 14. With this airmass and no snow they string together two straight sub freezing highs and a high of 35 today... Helps to have a little inversion going. 

 

This is very general, but it almost seems like if 850s aren't a lot colder than -10c we are almost better off with home grown surface cold and a relatively warm upper airmass.

 

I have probably seen more sub-35 days with 850s around 5c in my lifetime than I have with 850s around -10c. Usually a lot of mixing with 850s in that range, but not quite cold enough to give the airmass much of a true bite.

[Jesse]

This is essentially how PDX achieved its ridiculousness late January/early February 1950. Or even Eugene in December 2013.

 

Absolutely. Inversions have played a role in padding all the great winter months/stats around here. They are part of our winter climate.

[Deweydog]

This is very general, but it almost seems like if 850s aren't colder than -10c we are almost better off with home grown surface cold and a warm upper airmass.

 

I have probably seen more sub-35 days with 850s around 5c in my lifetime than I have with 850s around -10c.

It has to be cold somewhere to start. Deeply cold. These air masses are not by strict definition home grown.

[Jesse]

It has to be cold somewhere to start. Deeply cold. These air masses are not by strict definition home grown.

 

I'm not sure if you are understanding my post. I added some edits which might clarify things.

[Deweydog]

Absolutely. Inversions have played a role in padding all the great winter months/stats around here. They are part of our winter climate.

Definitely. It's a little unfortunate this particular event didn't have a little more bite initially, perhaps thicknesses in the 515dm neighborhood. That much turned over dry advection followed up with an inversion would have put out some incredibly crooked numbers.

[Dave]

Absolutely. Inversions have played a role in padding all the great winter months/stats around here. They are part of our winter climate.

This is true.  I dread them when there is no snow cover though.  Having lived in both Eugene and Portland, I can say that Eugene is far more susceptible to multi day, subfreezing inversions that fog us in.  The inversion still exists in Portland, but it tends to be sunny and cold, but a bit warmer.  Much better than foggy and cold.  Inversions happen frequently every single winter.

[SilverFallsAndrew]

People forget that the fogversion coldness of January 2013 started with a cold airmass, it was kind of a glancing blow west of the Cascades, but I think the initial airmass had -8/-9C 850mb temps. 

[SilverFallsAndrew]

Inversions can last forever AFAIC when there's still 8" of snowcover.

 

I have always thought January 1930 probably was a very inversiony month...

[Deweydog]

I'm not sure if you are understanding my post. I added some edits which might clarify things.

I get what you're saying, but I also think you might be a little jaded by what has been a winter where actual cold advection has been pretty unimpressive. Look at February 2014. 2-5 did it right.

[Phil]

Rub it in why don't ya?

 

This is the dewpoint hell I have to suffer through. This is only the average daily maximum. The absolute maximums are several degrees higher.

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/ED6F851D-DDA0-4BCC-BDC3-04E6D2E767D5_zpsuptz4b0a.png

[MossMan]

There is still a small pile left from our deranged snowman that my daughter and I made on Dec. 23rd...so there is that! I want more snow though. Currently 29 degrees, last below freezing evening for a while unfortunately.

[Jesse]

I get what you're saying, but I also think you might be a little jaded by what has been a winter where actually cold advection has been pretty unimpressive. Look at February 2014. 2-5 did it right.

Sure. Like I said it was a very general observation.

 

And wasn't 2-5-14 down in the -13c neighborhood?

[Jesse]

People forget that the fogversion coldness of January 2013 started with a cold airmass, it was kind of a glancing blow west of the Cascades, but I think the initial airmass had -8/-9C 850mb temps.

I think the coldest days happened several days later though, once an inversion formed.

[Deweydog]

Sure. Like it said is was a very general observation.

 

And wasn't 2-5-14 down in the -13c neighborhood?

It was.

[Jesse]

This is true.  I dread them when there is no snow cover though.  Having lived in both Eugene and Portland, I can say that Eugene is far more susceptible to multi day, subfreezing inversions that fog us in.  The inversion still exists in Portland, but it tends to be sunny and cold, but a bit warmer.  Much better than foggy and cold.  Inversions happen frequently every single winter.

 

The nature of the inversion in Eugene vs Portland is pretty pattern dependent. Often Portland will be colder with the wind since it is physically closer to the basin cold pool. Might still feel warmer than cold fog though. Depends on how strong the wind is.

[BLI snowman]

I have always thought January 1930 probably was a very inversiony month...

I'm sure. Portland had 19 consecutive subfreezing days, there's no way that at least a handful of those didn't have above freezing 850mb temps.

[jaya]

I wish it weren't the case, I don't want to turn it into a police state.

Actually, I wouldn't want that either. Just some of the arguments are so childish!

[Jesse]

I'm sure. Portland had 19 consecutive subfreezing days, there's no way that at least a handful of those didn't have above freezing 850mb temps.

 

You have to wonder if we were going into a long term +PNA pattern at the moment if we could start to piece together a pretty impressive stretch.

[SilverFallsAndrew]

Sure. Like I said it was a very general observation.

 

And wasn't 2-5-14 down in the -13c neighborhood?

 

I don't think 850s verified that cold. IbrChris would know for sure...

[jaya]

Any thoughts about the possible low snow levels at the end of the week?

Hi MossMan,

 

Actually, I have not been thinking about that. I am more concerned about the heavy rain, flooding and avalanche potential in the next few days. I have also seen the potential for some wind storms on a few runs. We need to get through this first.  I think that the pattern in the pattern in the 3-6 day period will evolve depending on how the details in the short term develop.

[BLI snowman]

You have to wonder if we were going into a long term +PNA pattern at the moment if we could start to piece together a pretty impressive stretch.

Already been fairly impressive. 4/5 days below freezing at PDX and 5 consecutive for some others in the metro area. Have to think tomorrow has a shot as well assuming the east wind holds on through midnight.

[Deweydog]

You have to wonder if we were going into a long term +PNA pattern at the moment if we could start to piece together a pretty impressive stretch.

It's self-perpetuating, but there would be slow moderation with the fact cold pool eastside would slowly moderate without an ability to turnover somewhat. Diurnal swings would shrink further and you'd see slow recoveries with each day's heating cycle. You can already see this pattern in The Dalles and Pasco.

[Jesse]

Already been fairly impressive. 4/5 days below freezing at PDX and 5 consecutive for some others in the metro area. Have to think tomorrow has a shot as well assuming the east wind holds on through midnight.

It definitely has. I guess I meant more like a week+.

[luminen]

This is true.  I dread them when there is no snow cover though.  Having lived in both Eugene and Portland, I can say that Eugene is far more susceptible to multi day, subfreezing inversions that fog us in.  The inversion still exists in Portland, but it tends to be sunny and cold, but a bit warmer.  Much better than foggy and cold.  Inversions happen frequently every single winter.

 

January 2013 was fun in Eugene. It felt like China under that inversion.

 

The high/low was 29/28 on January 13th that year. 

[luvssnow_spokane]

Looks like we could potentially develop some wind next week. Rain looks to be in the bucket loads with pretty high snow levels. Flooding?  Yes possibly. Depending on how some of these pretty deep lows track we could be looking at some decent wind here. It may be a warmer week, but I also think it will be very interesting and even exciting from an intensity standpoint... May be signals for cooler heading into the weekend and beyond.

[Jesse]

It's self-perpetuating, but there would be slow moderation with the fact cold pool eastside would slowly moderate without an ability to turnover somewhat. Diurnal swings would shrink further and you'd see slow recoveries with each day's heating cycle. You can already see this pattern in The Dalles and Pasco.

Interesting. I have always liked to do thought experiments about what a setup like this would eventually do if it were just allowed to sit here without any sort of upper level disturbance.

[Deweydog]

Interesting. I have always liked to do thought experiments about what a setup like this would eventually do if it were just allowed to sit here without any sort of upper level disturbance.

Theoretically it would eventually become mixed out. Might take weeks but eventually solar energy would eat away the inversion from the top down as the surface slowly moderates.

[jaya]

Rub it in why don't ya?

 

This is the dewpoint hell I have to suffer through. This is only the average daily maximum. The absolute maximums are several degrees higher.

 

I have lived in several parts of the country, and am from Florida originally.  I am so happy with our climate in the northwest! Our summers are the best. Our microclimates are very interesting. If you want snow, it is a short drive to the mountains (if the traffic doesn't bother you!), and it really isn't any more cloudy or damp here than it is in the upper midwest (Cleveland comes to mind).  It is really not cold in the winter (I can get used to 30s to 50s much easier than -25 with wind!)  It is a bit boring when it comes to severe weather, snowstorms, etc. but - whose complaining - we can watch those on the TV news!  Nothing like rebuilding your house after a hurricane, watching a neighbor lose everything in a tornado, ...  I think I'll stay here and drive around to get my weather fix!  I love snow, but that is not all there is in the weather world!

[crf450ish]

[Dave]

January 2013 was fun in Eugene. It felt like China under that inversion.

 

The high/low was 29/28 on January 13th that year. 

Were you a Eugene visitor, or resident back then?  I can say that I absolutely hate fog.  We get tons of it here.  More than any other location in the valley.