January 2017 Observations and Model Discussion for the Pacific Northwest

[IbrChris]

PDX tracking 5 degrees colder than yesterday through 11am.

 

A subfreezing high seems pretty achievable. 

Some warming at 850 mb that has served to strengthen the inversion. I'm betting the high is 29 or 30 at PDX.

[wx_statman]

That was the coldest reading at the Hillsboro airport (where obs started in 1998) until this morning. From what I can tell this morning's low of 3 looks like the coldest temp in Hillsboro since Dec 1972.

 

Yeah, looks like it. I would have guessed December 1990 without looking, but apparently they only reached 6.

[Jesse]

I still have a hard time remembering that SLE is now a UHI location. Growing up, SLE was right there with EUG and HIO as radiational cooling rock stars.

Hopefully those places aren't swallowed up by suburban sprawl in the future. But I wouldn't rule the possibility out.

 

It's always a shame to lose those rural benchmark stations. Makes it harder to judge patterns/airmasses and also to detect any climate change signal.

[IbrChris]

The only analogs I can find for a major SSW/PV breakdown under a matching low frequency tropical forcing regimen are 1988/89 and 1978/79, both of which featured excitement in the western states during and/or after the SSW/PV breakdown process. The SSW of JAN/FEB 1989 was one of the most prolific events to ever occur, just behind the 2008/09 event.

 

1978/79:

 

 

1988/89:

 

This winter seems a lot like 1978-79 to me..if we follow suit here the resemblance would border on uncanny.

[BLI snowman]

1996 was such a perfect storm. 6 consecutive highs below freezing, followed by 4 consecutive days with 1"+ of rain (at PDX).

 

I'm working with a grad student @PSU who's studying succession ecology on the Muddy River Lahar up on St. Helens. Apparently the most destructive mudflows up there after the 1980 eruption were in Feb 1996. Kinda cool learning that. 

 

We haven't really seen a significant snowmelt flood since 1996, at least in SW WA (January 2012 was bad further south). Probably just about getting to the point of being due.

[SilverFallsAndrew]

Hopefully those places aren't swallowed up by suburban sprawl in the future. But I wouldn't rule the possibility out.

 

It's always a shame to lose those rural benchmark stations. Makes it harder to judge patterns/airmasses and also to detect any climate change signal.

The thing about SLE is it isn't just houses near it, it is big box stores with giant asphalt parking lots, warehouses, and office complexes.

[IbrChris]

Yeah, looks like it. I would have guessed December 1990 without looking, but apparently they only reached 6.

I think the old Hillsboro COOP station which was located just south of town near Dairy Creek wetlands is a bit warmer than the HIO location...I imagine HIO would have hit close to 3 or 4 in 1990. Compare 4 in 1998 at HIO vs 11 in 1998 at PDX. 12 at PDX in 1990...probably 3-5 at HIO.

 

Not much snowcover in Dec 1990...had it been anywhere close to what we have currently sub-zero would have been probable at HIO and singles at PDX.

[SilverFallsAndrew]

Hopefully those places aren't swallowed up by suburban sprawl in the future. But I wouldn't rule the possibility out.

 

It's always a shame to lose those rural benchmark stations. Makes it harder to judge patterns/airmasses and also to detect any climate change signal.

 

I am pretty familiar with EUG, it doesn't appear in danger of being swallowed up anytime soon. West Eugene is where a lot of the cities growth is, but significant development is still a ways away. A lot of the growth in that area too is residential, which wouldn't be as bad as having a Wal-Mart, Costco, 3 car dealerships, Lowe's, and several office parks go in right next door, which is literally what happened at SLE in the past 20 years. 

[BLI snowman]

Some warming at 850 mb that has served to strengthen the inversion. I'm betting the high is 29 or 30 at PDX.

 

You can definitely notice the pickup in low level moisture today right away just looking outside. Lots of gunk.

 

Makes me wonder if the next few afternoons may be completely socked in.

[IbrChris]

It's just so rare we get the necessary combination of snowcover, clear nights and fairly light wind to achieve real cold temps around here. Snow usually comes on the heels of a transition event and warming. Even if we somehow manage snow and clear skies, the east wind is often raging. Many times we manage clear skies and light winds but the snow cover is very little or nonexistent.

For arguably the first time since the 1980s we managed to get all three in the Portland metro...the stars aligned...even though the current airmass is subpar from an upper level perspective. If we could have managed this going into an arctic blast we would be talking lows that would rival Jan/Feb 1950.

[SilverFallsAndrew]

I think the old Hillsboro COOP station which was located just south of town near Dairy Creek wetlands is a bit warmer than the HIO location...I imagine HIO would have hit close to 3 or 4 in 1990. Compare 4 in 1998 at HIO vs 11 in 1998 at PDX. 12 at PDX in 1990...probably 3-5 at HIO.

 

Not much snowcover in Dec 1990...had it been anywhere close to what we have currently sub-zero would have been probable at HIO and singles at PDX.

 

Yeah 1990 with this much snow cover would have been a beast. December 1919, January 1930, Jan 1950, show what deep snow cover and a bitterly cold airmass can do.

[SilverFallsAndrew]

It's just so rare we get the necessary combination of snowcover, clear nights and fairly light wind to achieve real cold temps around here. Snow usually comes on the heels of a transition event and warming. Even if we somehow manage snow and clear skies, the east wind is often raging. Many times we manage clear skies and light winds but the snow cover is very little or nonexistent.

 

For arguably the first time since the 1980s we managed to get all three in the Portland metro...the stars aligned...even though the current airmass is subpar from an upper level perspective. If we could have managed this going into an arctic blast we would be talking lows that would rival Jan/Feb 1950.

 

There is still our upcoming late January/Early February event.

[wx_statman]

I think the old Hillsboro COOP station which was located just south of town near Dairy Creek wetlands is a bit warmer than the HIO location...I imagine HIO would have hit close to 3 or 4 in 1990. Compare 4 in 1998 at HIO vs 11 in 1998 at PDX. 12 at PDX in 1990...probably 3-5 at HIO.

 

Not much snowcover in Dec 1990...had it been anywhere close to what we have currently sub-zero would have been probable at HIO and singles at PDX.

 

-22C's and snow cover...I imagine we would have seen similar readings to December 1919. On either side of zero in the city, and -10's in outlying areas. Just drives home the point of how rare a decent snowcover is around here. 

[IbrChris]

There is still our upcoming late January/Early February event.

Pray for #AKblock to return.

 

CFS has it but it's still beyond the range of Euro and GFS ensembles. We are looking at low snow levels (maybe flirting with valley floors) in the extended period...although the 500 mb pattern doesn't suggest an arctic blast to me, mostly just cold onshore flow. If it wasn't for this 2-3 day warm spell next week the Coast Range might have been looking at record snow depths by late Jan.

[Jesse]

Yeah, some creeks could be at near record highs.  Most of those higher foothills where they originate now have 2-3' of snowpack, which is pretty comparable to where they were in early February 1996. Just not looking like as beefy of a deluge, as you said.

 

Going to suck watching all of this melt, but can't complain too much since we will be sitting at 5-6 days with sunny snowcover and cold temps by then.

 

Also sort of fun to have it go out with a bang. This snow realizes that it's better to burn out than fade away.

[IbrChris]

-22C's and snow cover...I imagine we would have seen similar readings to December 1919. On either side of zero in the city, and -10's in outlying areas. Just drives home the point of how rare a decent snowcover is around here. 

Yep Dec 1919 really shows what we can achieve with the perfect combination (snow, clear, calm) along with an arctic airmass.

[Jesse]

1996 was such a perfect storm. 6 consecutive highs below freezing, followed by 4 consecutive days with 1"+ of rain (at PDX).

 

I'm working with a grad student @PSU who's studying succession ecology on the Muddy River Lahar up on St. Helens. Apparently the most destructive mudflows up there after the 1980 eruption were in Feb 1996. Kinda cool learning that. 

 

Very interesting. What is your area of study here? This sort of thing is the direction my future career is likely trending.

[MossMan]

Well trying to think back I believe the last time Lake Goodwin had as thick of ice as it currently has would be 1992/93. Been a while.

[Timmy Supercell]

It's just so rare we get the necessary combination of snowcover, clear nights and fairly light wind to achieve real cold temps around here. Snow usually comes on the heels of a transition event and warming. Even if we somehow manage snow and clear skies, the east wind is often raging. Many times we manage clear skies and light winds but the snow cover is very little or nonexistent.

 

For arguably the first time since the 1980s we managed to get all three in the Portland metro...the stars aligned...even though the current airmass is subpar from an upper level perspective. If we could have managed this going into an arctic blast we would be talking lows that would rival Jan/Feb 1950.

 

I got a serious question. What would Dec 2013 had done here if I had an 18-24" pack here?? lol 

 

-30 to -35 at KLMT? There was little snowpack at all in Dec 2013 here. Something to consider.

[Jesse]

There is still our upcoming late January/Early February event.

 

For some reason I can't shake the feeling that we will get something in that period too. Could just be subconcious wishcasting I guess. But there is that kind of vibe to this winter that we will get hit again. As I said the other day, the 500mb pattern has teased us a lot so far, but it has yet to fully unload...

[IbrChris]

I got a serious question. What would Dec 2013 had done here if I had an 18-24" pack here?? lol 

 

-30 to -35 at KLMT? There was little snowpack at all in Dec 2013 here. Something to consider.

Tough to say...but I don't think Klamath Falls (either airport or old COOP station) has ever hit -30 which calls into question whether those temps are possible there, or if they are that the return period for such an event is extremely long (centuries or more).

 

Generally the radiative properties of snow don't keep increasing the deeper it gets...1" of fairly continuous coverage is about as effective at radiating heat as a 24" depth. Of course it helps to have snow-covered roofs and roads as those dark surfaces would otherwise absorb sunlight during the day and radiate warmth at night.

[Jesse]

I am pretty familiar with EUG, it doesn't appear in danger of being swallowed up anytime soon. West Eugene is where a lot of the cities growth is, but significant development is still a ways away. A lot of the growth in that area too is residential, which wouldn't be as bad as having a Wal-Mart, Costco, 3 car dealerships, Lowe's, and several office parks go in right next door, which is literally what happened at SLE in the past 20 years. 

 

Interesting info. I am going to google earth the SLE location. There is a neat feature on there where you can look at past satellite images over the years. Great way to get a feel for land use changes over time.

[epiceast]

Hopefully those places aren't swallowed up by suburban sprawl in the future. But I wouldn't rule the possibility out.

 

It's always a shame to lose those rural benchmark stations. Makes it harder to judge patterns/airmasses and also to detect any climate change signal.

Should be using pass locations for that imo. Upper atmosphere is more consistent than the lowlands.

[Jesse]

You can definitely notice the pickup in low level moisture today right away just looking outside. Lots of gunk.

 

Makes me wonder if the next few afternoons may be completely socked in.

 

Could be some pretty chilly low clouds and fog. Been awhile since we've seen a foggy day around 30.

 

PDX is getting set up pretty good for scoring a sub-35 average this month. Just have to hope next week's torch doesn't torch too hard or last too long and that we go back into a reasonably chilly pattern in short order.

[BLI snowman]

For some reason I can't shake the feeling that we will get something in that period too. Could just be subconcious wishcasting I guess. But there is that kind of vibe to this winter that we will get hit again. As I said the other day, the 500mb pattern has teased us a lot so far, but it has yet to fully unload...

 

I think an honest to goodness arctic event and perhaps one more area-wide snowfall would be enough to put this winter into the category of the great ones for the Portland region.

[Timmy Supercell]

Tough to say...but I don't think Klamath Falls (either airport or old COOP station) has ever hit -30 which calls into question whether those temps are possible there, or if they are that the return period for such an event is extremely long (centuries or more).

 

Generally the radiative properties of snow don't keep increasing the deeper it gets...1" of fairly continuous coverage is about as effective at radiating heat as a 24" depth. Of course it helps to have snow-covered roofs and roads as those dark surfaces would otherwise absorb sunlight during the day and radiate warmth at night.

 

Ah, still learning the ins-and-outs of all this. KLMT had an all time low of -25 on 01/23/1962. I'm sure a few older stations may have had slightly cooler (KLMT only goes back to 1948 or something like that). The station that was set up in 1887 probably saw a few more lows like that.

[Jesse]

Should be using pass locations for that imo. Upper atmosphere is more consistent than the lowlands.

 

Weather balloons are also good for that sort of thing. But there is something about having data on the ground.

[MossMan]

For some reason I can't shake the feeling that we will get something in that period too. Could just be subconcious wishcasting I guess. But there is that kind of vibe to this winter that we will get hit again. As I said the other day, the 500mb pattern has teased us a lot so far, but it has yet to fully unload...

We are on our 8th or so warning shot up here...I have a hunch all of us are going to experience a large grand finale kill/glory shot here in about 2 weeks.

[IbrChris]

Only a few occasions of -20 at Klamath Falls:

-25 1/23/1962

-24 1/15/1888
-20 12/8/2013

-20 1/7/1982

Recently a pair of -19 on 1/5 and 1/6/2017

To put this month into perspective in 1972 Klamath Falls reached -17, in 1990 -16, in 1919 -16 and in 1950 -12. Granted the airport is a bit colder than the city itself.
 

[BLI snowman]

Could be some pretty chilly low clouds and fog. Been awhile since we've seen a foggy day around 30.

 

PDX is getting set up pretty good for scoring a sub-35 average this month. Just have to hope next week's torch doesn't torch too hard or last too long and that we go back into a reasonably chilly pattern in short order.

 

They were at 30.2 coming into today, should keep it there or lower through the 16th. 

 

And already when you look at the 30 days ending today (12/14 to 1/13), we're going to be talking about some pretty D**n good averages. Would guess around freezing at the airport and around 30 in outlying areas.

[wx_statman]

Very interesting. What is your area of study here? This sort of thing is the direction my future career is likely trending.

 

Now, I'm only a volunteer lab assistant for 4 hours a week.    Its something I decided to do just for the sake of having relevant experience in Physical Geography. 

 

The grad student I'm helping is studying tree rings up there. Comparing tree rings from post-1980 growth with nearby undisturbed forest. I know the goal of his masters thesis is to figure out how and in what order different tree species colonize an area (primary succession). The Muddy River Lahar has something like 7-8 different tree species that have crept back in over the last 30+ years. Mt. St Helens provides what's probably the best location in the lower 48 to study this sort of thing. 

 

Personally, I'm just taking core samples and scanning them into a computer program which marks the individual tree rings. Then I go through and QC everything, because the digital ID'ing is far from perfect. Exciting stuff. 

[MossMan]

Currently 29 here at my house.

[IbrChris]

Ah, still learning the ins-and-outs of all this. KLMT had an all time low of -25 on 01/23/1962. I'm sure a few older stations may have had slightly cooler (KLMT only goes back to 1948 or something like that). The station that was set up in 1887 probably saw a few more lows like that.

Unfortunately the earlier station (dating to 1887) seems to have been in the present city (and thus not quite as ideal for radiational cooling as the airport to the SE). Fort Klamath I believe was located farther north but I think I saw an instance or two of -30s in their records.

[SilverFallsAndrew]

Unfortunately the earlier station (dating to 1887) seems to have been in the present city (and thus not quite as ideal for radiational cooling as the airport to the SE). Fort Klamath I believe was located farther north but I think I saw an instance or two of -30s in their records.

 

The north end of the Klamath Basin up towards Agency Lake is a MUCH better area for radiational cooling. 

[Kayla]

Pretty impressive noon hour temps. Could definitely see some sub 30's today with the high clouds and inversion setting up.

 

HIO -  24º

PDX - 27º

VUO - 28º

[Timmy Supercell]

Unfortunately the earlier station (dating to 1887) seems to have been in the present city (and thus not quite as ideal for radiational cooling as the airport to the SE). Fort Klamath I believe was located farther north but I think I saw an instance or two of -30s in their records.

 

Yes, some folks who live up there said with confidence they saw -30 on 12/08/2013. We get many people from nearby towns commuting in K-Falls and we were definitely not the coldest here. Unsure if all of them have personal stations though.

[IbrChris]

Going to suck watching all of this melt, but can't complain too much since we will be sitting at 5-6 days with sunny snowcover and cold temps by then.

 

Also sort of fun to have it go out with a bang. This snow realizes that it's better to burn out than fade away.

IMO couldn't have hoped for a better outcome than to see a foot of snow followed by nearly a week of sunny/clear skies. I wouldn't have believed it had I not witnessed it, considering it's Portland where gray and snow > rain is the norm.

[SilverFallsAndrew]

Interesting info. I am going to google earth the SLE location. There is a neat feature on there where you can look at past satellite images over the years. Great way to get a feel for land use changes over time.

 

After you look at SLE, check out EUG on google earth...You will notice the difference...

[IbrChris]

After you look at SLE, check out EUG on google earth...You will notice the difference...

OLM has the benefit of having quite a bit of undeveloped/lightly developed land around it especially on the W, S and E sides. North end has some business parks and small industry. Also a lot of the airport grounds are grass with tarmac limited to the runways themselves as opposed to other bigger/busier airports.

 

EUG is even better situated w.r.t. natural ground cover and minimal development.

[wx_statman]

Unfortunately the earlier station (dating to 1887) seems to have been in the present city (and thus not quite as ideal for radiational cooling as the airport to the SE). Fort Klamath I believe was located farther north but I think I saw an instance or two of -30s in their records.

 

Yeah, Fort Klamath hit -34 in Feb 1884 and -39 in Jan 1888 (when K Falls City hit -24). Although with that being a fort station, we run into questions of siting.