December 2020 Weather Observations for the PNW

[SilverFallsAndrew]

1 minute ago, Deweydog said:

A solidly cool February still seems like a good bet, although I do ponder the symmetry of a 2019 SSW/ENSO doppelgänger payback.  

Yea, Some stations have had 4 straight below average Februaries, though last February was a mixed bag, PDX was above average, but SLE was below average, powered by an astonishing number of sub-freezing lows. 

[AbbyJr]

2 hours ago, Cloud said:

Obviously I'm pretty noobish with the SSW stuff. SSW is gonna happen! But for us, do we want the SPV to split or nah? 

Good question. Perhaps Phil can answer?

[Phil]

As the jet extends to open January (associated with +EAMT/Siberian High descent), essentially the entire pool of vodka cold will spill onto Putin’s side of the pole, while the TPV evacuates North America (for now).

[BLI snowman]

33 minutes ago, Phil said:

As the jet extends to open January (associated with +EAMT/Siberian High descent), essentially the entire pool of vodka cold will spill onto Putin’s side of the pole, while the TPV evacuates North America (for now).

Fugly.

Maybe that thing will supercharge and just bust on through to the SE as the Pacific quiets down. That was the basic progression in 1989, the last "Siberian Express". 

[Phil]

52 minutes ago, AbbyJr said:

Good question. Perhaps Phil can answer?

1989 was a displacement (initially).

Looking back at it on the noaa psl site, what happened in 1989 was one of the most remarkable progressions of the satellite era. Strongest vortex on record gets knocked into Eurasia (initial wave-1) then gets blasted right back into North America where wave-2 response takes over and destroys it...all this occurring in just over a week.

That entire system, surf zone, from top to bottom, troposphere to stratosphere, just buckles and self-destructs at the end of January 1989. No lag. No complicated, drawn out shenanigans like 2019. It all happens in unison.

[snow_wizard]

12 minutes ago, Phil said:

1989 was a displacement (initially).

Looking back at it on the noaa psl site, what happened in 1989 was one of the most remarkable progressions of the satellite era. Strongest vortex on record gets knocked into Eurasia (initial wave-1) then gets blasted right back into North America where wave-2 response takes over and destroys it...all this occurring in just over a week.

That entire system, surf zone, from top to bottom, troposphere to stratosphere, just buckles and self-destructs at the end of January 1989. No lag. No complicated, drawn out shenanigans like 2019. It all happens in unison.

I remember intense cold was in place in Alaska for a while before it blasted into the NW United States as well.

[snow_wizard]

The 18z GFS ends on a decent note.  A high over the GOA, a Kona low,  and pretty chilly air about to enter the NW.  One of the better looking runs for the end of the run in a while.

[Phil]

26 minutes ago, BLI snowman said:

Fugly.

Maybe that thing will supercharge and just bust on through to the SE as the Pacific quiets down. That was the basic progression in 1989, the last "Siberian Express". 

Definitely possible. I’ve spent today looking back at reanalysis of satellite-era PNW arctic outbreaks and wow, there’s a lot to unpack because they’ve taken multiple routes in the past.

However, the post-1998 era seems to be distinctly different from the 1977-1998 era in terms of the loading patterns and their teleconnective “fabrics”, so to speak.

Many of the more recent cold patterns (and SSWings) were preceded by Siberian High descents and +EAMT/jet extensions, including non-SSW examples like 2016/17, which unsurprisingly tend to be clustered in +QBO/-ENSO regimes. The pattern flips usually occur during the subsequent retraction phase, though some happen faster than others.

Looking at 2020/21, there’s a remarkable similarity to many of those cases that transitioned to significantly colder patterns in the NW US ~ 3 weeks later (give or take a week).

 

 

 

 

 

[snow_wizard]

1 hour ago, Deweydog said:

A solidly cool February still seems like a good bet, although I do ponder the symmetry of a 2019 SSW/ENSO doppelgänger payback.  

We're probably getting close to the end of the reign of cold Februaries.  Historically they come in bunches, but usually don't span more than a decade or so.  Sometimes after a cluster of them we can go for a long time before getting another one.

[snow_wizard]

4 minutes ago, Phil said:

Definitely possible. I’ve spent today looking back at reanalysis of satellite-era PNW arctic outbreaks and wow, there’s a lot to unpack because they’ve taken multiple routes in the past.

However, the post-1998 era seems to be distinctly different from the 1977-1998 era in terms of the loading patterns and their teleconnective “fabrics”, so to speak.

Many of the more recent cold patterns (and SSWings) were preceded by Siberian High descents and +EAMT/jet extensions, including non-SSW examples like 2016/17, which unsurprisingly tend to be clustered in +QBO/-ENSO regimes.

Looking at 2020/21, there’s a remarkable similarity to many of those cases that transitioned to significantly colder patterns in the NW US ~ 3 weeks later (give or take a week).

 

 

 

 

 

I think we have a shot at something great.  Going to be interesting to see how the next couple of weeks unfold.

[BLI snowman]

5 minutes ago, Phil said:

Definitely possible. I’ve spent today looking back at reanalysis of satellite-era PNW arctic outbreaks and wow, there’s a lot to unpack because they’ve taken multiple routes in the past.

However, the post-1998 era seems to be distinctly different from the 1977-1998 era in terms of the loading patterns and their teleconnective “fabrics”, so to speak.

Many of the more recent cold patterns (and SSWings) were preceded by Siberian High descents and +EAMT/jet extensions, including non-SSW examples like 2016/17, which unsurprisingly tend to be clustered in +QBO/-ENSO regimes.

Looking at 2020/21, there’s a remarkable similarity to many of those cases that transitioned to significantly colder patterns in the NW US ~ 3 weeks later (give or take a week).

 

 

 

 

 

The late 1970s into 1980s seemed like a unique era in terms of how extreme and broadly the 500mb swings were able to maneuver. It was an incredibly anomalous time for major coldwaves in the middle latitudes. The 1976-77/1977-78/1978-79 trio was the start of it as the PDO flipped and most of the U.S. froze. But it carried over throughout the next decade plus with almost every winter sans the major Ninos featuring some massive airmasses even as the global background state began to re-warm. There was a distinct change as the 1990s dragged on and by 1999 or so it definitely felt like we had entered a different era. 

[SouthHillFrosty]

https://twitter.com/rustywx/status/1342875214980460545?s=21

The second guy should definitely join the forums 

[Gradient Keeper]

18z GEFS Day 1.5 SSWE has commenced. Timing moving ahead.

Day 3

[AbbyJr]

1 hour ago, Phil said:

1989 was a displacement (initially).

Looking back at it on the noaa psl site, what happened in 1989 was one of the most remarkable progressions of the satellite era. Strongest vortex on record gets knocked into Eurasia (initial wave-1) then gets blasted right back into North America where wave-2 response takes over and destroys it...all this occurring in just over a week.

That entire system, surf zone, from top to bottom, troposphere to stratosphere, just buckles and self-destructs at the end of January 1989. No lag. No complicated, drawn out shenanigans like 2019. It all happens in unison.

February 1989 would have very memorable for those who experienced it.

On average though, is a vortex displacement or split better for getting arctic air into the PNW?

[Deweydog]

12 minutes ago, AbbyJr said:

February 1989 would have very memorable for those who experienced it.

On average though, is a vortex displacement or split better for getting arctic air into the PNW?

I don’t think there’s a way to put any aspects of a major SSW into as neat a box as you’d like to.  The very nature of the event is that of pattern upheaval and more of a free flow of cold air masses. Beyond that, good luck...

[snow_wizard]

6 minutes ago, AbbyJr said:

February 1989 would have very memorable for those who experienced it.

On average though, is a vortex displacement or split better for getting arctic air into the PNW?

A displacement like 1989 is hard to pull off.  A split makes it easier for things to move.

[snow_wizard]

16 minutes ago, DJ Droppin said:

18z GEFS Day 1.5 SSWE has commenced. Timing moving ahead.

Day 3

I think it's locked in now.

[TheNewCulverJosh]

2 minutes ago, snow_wizard said:

A displacement like 1989 is hard to pull off.  A split makes it easier for things to move.

Back before we had access to models.  Was the days of flashlights out the bedroom window to see flakes falling.  I remember doing it more times than I can count.

[snow_wizard]

As you can see the 500mb pattern was totally epic with the Feb 1989 blast.  What a beast!

 

[snow_wizard]

8 minutes ago, TheNewCulverJosh said:

Back before we had access to models.  Was the days of flashlights out the bedroom window to see flakes falling.  I remember doing it more times than I can count.

Me too.  I do remember there was a lot of excitement in late January 1989 speculating whether the cold would get knocked down here or not.  I still remember the evening the NWS announced it was coming.  Very exciting!

[Brian_in_Leavenworth]

17 minutes ago, snow_wizard said:

Me too.  I do remember there was a lot of excitement in late January 1989 speculating whether the cold would get knocked down here or not.  I still remember the evening the NWS announced it was coming.  Very exciting!

As legendary as 1989 was, I think it would have disappointed a lot of people here.  IMHO, February 2019 was far better.  Though I think a lot of areas got snow, some areas did not.  I was in Bellingham, and just had a trace.  

The other thing people would have found disappointing was that it was a short lived event.  Bellingham and Seattle only had 4 days with highs below 32, and after that temps quickly got back to normal.  There was some snow in early March, but that was a separate event.

Portland stayed cool longer than Seattle, probably gorge winds kept it cool.  But it too only had about 4 days below freezing.  

[Meatyorologist]

2 minutes ago, Brian_in_Leavenworth said:

As legendary as 1989 was, I think it would have disappointed a lot of people here.  IMHO, February 2019 was far better.  Though I think a lot of areas got snow, some areas did not.  I was in Bellingham, and just had a trace.  

The other thing people would have found disappointing was that it was a short lived event.  Bellingham and Seattle only had 4 days with highs below 32, and after that temps quickly got back to normal.  There was some snow in early March, but that was a separate event.

Portland stayed cool longer than Seattle, probably gorge winds kept it cool.  But it too only had about 4 days below freezing.  

To be quite honest, I would be absolutely ecstatic over a February 1989 repeat. As short-lived as it was, the magnitude was unreal, with highs in the teens virtually everywhere. Magnitude>volume for me; although my opinion might be a bit biased given that I've never witnessed a top-tier arctic blast here, save for 2006/2008/2010

[paulb/eugene]

000 
TTAA00 KSEA 290957
LTL CHG IN BASIC PATRN OF STG W-E JET ALG 55N...HI HGTS OVR WA AND LTL
IF ANY PVA OR SIGNFNT S/WVS MVG THRU STATE. BAD STLT PICS POORLY SHW
BACLIN BAND ACRS VRISL MVG SLWLY SWD IN RSPNS TO CD UPR LO IN SRN AK
SO HIGHEST POPS AT UIL AND BLI. BACLIN BAND LIKELY TO STALL JUST N OF
WA. BIG QUESTION AFT 48 HRS IS HOW FAR S WILL CD UPR AK LO DROP. WILL
IT CONT TO DROP STRGT SWD TWD WA OR WILL IT STRT RTRGRTNG W BOUND AND
END UP UNDER BERING SEA BLK. THIS PUTS WA IN CONTD RDGG WITH ANTICYC
FLO. NEW RUN OF MRF SHLD SHED SM LIGHT ON THIS. ERN WA STUCK IN THE
SOUP HWVR BOTH NGM AND MRF INCRS THE SLY GRAD ACRS ERN WA ON MON SO
SE AND XTRM E PRTS COULD TMPRLY BRKOUT WITH MAX TMPS MVG UP SM. FOG
AND ST TDA WILL HOLD DWN MAX TMPS BLO WHAT MOS SAYS. INTERESTING TO
NOTE THAT BOTH NGM AND LFM DVLP 1072 MB ARCTIC HI IN ERN AK IN 48
HRS WHICH WOULD SHATTER THE PRVS N AMRCN RCRD HI PRES OF 1067.6 MB
SET ON JAN 1 1974 IN THE YUKON TERR. NEW 06Z MRF RUN JUST CAME IN
AND NEW 120 HR VALID 00Z FRI WILL KNOCK YOUR SOCKS OFF COMPARED TO PRVS
RDGG PATRN. REFUSE TO JUMP ON THIS UNTIL 2ND MRF RUN TNGT CONFIRMS
OR ELSE YO YOS BACK TO RDGG. MRF TYPICALLY POOR WITH BLKS SPLTS
AND NRN FLO S/WVS COMNG DWN FM AK. HWVR =IF CORRECT HANG ONTO YOUR
SOCKS. BC

[paulb/eugene]

Just now, paulb/eugene said:

000 
TTAA00 KSEA 290957
LTL CHG IN BASIC PATRN OF STG W-E JET ALG 55N...HI HGTS OVR WA AND LTL
IF ANY PVA OR SIGNFNT S/WVS MVG THRU STATE. BAD STLT PICS POORLY SHW
BACLIN BAND ACRS VRISL MVG SLWLY SWD IN RSPNS TO CD UPR LO IN SRN AK
SO HIGHEST POPS AT UIL AND BLI. BACLIN BAND LIKELY TO STALL JUST N OF
WA. BIG QUESTION AFT 48 HRS IS HOW FAR S WILL CD UPR AK LO DROP. WILL
IT CONT TO DROP STRGT SWD TWD WA OR WILL IT STRT RTRGRTNG W BOUND AND
END UP UNDER BERING SEA BLK. THIS PUTS WA IN CONTD RDGG WITH ANTICYC
FLO. NEW RUN OF MRF SHLD SHED SM LIGHT ON THIS. ERN WA STUCK IN THE
SOUP HWVR BOTH NGM AND MRF INCRS THE SLY GRAD ACRS ERN WA ON MON SO
SE AND XTRM E PRTS COULD TMPRLY BRKOUT WITH MAX TMPS MVG UP SM. FOG
AND ST TDA WILL HOLD DWN MAX TMPS BLO WHAT MOS SAYS. INTERESTING TO
NOTE THAT BOTH NGM AND LFM DVLP 1072 MB ARCTIC HI IN ERN AK IN 48
HRS WHICH WOULD SHATTER THE PRVS N AMRCN RCRD HI PRES OF 1067.6 MB
SET ON JAN 1 1974 IN THE YUKON TERR. NEW 06Z MRF RUN JUST CAME IN
AND NEW 120 HR VALID 00Z FRI WILL KNOCK YOUR SOCKS OFF COMPARED TO PRVS
RDGG PATRN. REFUSE TO JUMP ON THIS UNTIL 2ND MRF RUN TNGT CONFIRMS
OR ELSE YO YOS BACK TO RDGG. MRF TYPICALLY POOR WITH BLKS SPLTS
AND NRN FLO S/WVS COMNG DWN FM AK. HWVR =IF CORRECT HANG ONTO YOUR
SOCKS. BC

This was the first Seattle AFD mentioning Feb 89

[bainbridgekid]

1 minute ago, paulb/eugene said:

000 
TTAA00 KSEA 290957
LTL CHG IN BASIC PATRN OF STG W-E JET ALG 55N...HI HGTS OVR WA AND LTL
IF ANY PVA OR SIGNFNT S/WVS MVG THRU STATE. BAD STLT PICS POORLY SHW
BACLIN BAND ACRS VRISL MVG SLWLY SWD IN RSPNS TO CD UPR LO IN SRN AK
SO HIGHEST POPS AT UIL AND BLI. BACLIN BAND LIKELY TO STALL JUST N OF
WA. BIG QUESTION AFT 48 HRS IS HOW FAR S WILL CD UPR AK LO DROP. WILL
IT CONT TO DROP STRGT SWD TWD WA OR WILL IT STRT RTRGRTNG W BOUND AND
END UP UNDER BERING SEA BLK. THIS PUTS WA IN CONTD RDGG WITH ANTICYC
FLO. NEW RUN OF MRF SHLD SHED SM LIGHT ON THIS. ERN WA STUCK IN THE
SOUP HWVR BOTH NGM AND MRF INCRS THE SLY GRAD ACRS ERN WA ON MON SO
SE AND XTRM E PRTS COULD TMPRLY BRKOUT WITH MAX TMPS MVG UP SM. FOG
AND ST TDA WILL HOLD DWN MAX TMPS BLO WHAT MOS SAYS. INTERESTING TO
NOTE THAT BOTH NGM AND LFM DVLP 1072 MB ARCTIC HI IN ERN AK IN 48
HRS WHICH WOULD SHATTER THE PRVS N AMRCN RCRD HI PRES OF 1067.6 MB
SET ON JAN 1 1974 IN THE YUKON TERR. NEW 06Z MRF RUN JUST CAME IN
AND NEW 120 HR VALID 00Z FRI WILL KNOCK YOUR SOCKS OFF COMPARED TO PRVS
RDGG PATRN. REFUSE TO JUMP ON THIS UNTIL 2ND MRF RUN TNGT CONFIRMS
OR ELSE YO YOS BACK TO RDGG. MRF TYPICALLY POOR WITH BLKS SPLTS
AND NRN FLO S/WVS COMNG DWN FM AK. HWVR =IF CORRECT HANG ONTO YOUR
SOCKS. BC

Fascinating. Also really cool to see how much AFD writing style has changed since then.

[Brian_in_Leavenworth]

3 minutes ago, Meatyorologist said:

To be quite honest, I would be absolutely ecstatic over a February 1989 repeat. As short-lived as it was, the magnitude was unreal, with highs in the teens virtually everywhere. Magnitude>volume for me; although my opinion might be a bit biased given that I've never witnessed a top-tier arctic blast here, save for 2006/2008/2010

Well certainly it was unique as to how cold it was, and North Whatcom County had wind gusts over 100 MPH and several buildings hadn roofs blown off.  And wind chills there were about-60, though I know these days they have revised wind chill charts and the actual  wind chill was not as extreme as that.  

But I was left with a feeling of wanting more.  Not just more snow, but a longer event.  It just gradually warmed up and after about 5 days it was all over.   Rivers and large lakes did not have time to freeze over.

2008 was also better IMHO for the same reasons, plus there was a white Christmas.  Hard to beat that. Didnt have extreme winds, and not as cold, but it was amazing.  Wh at makes January 1950 so great is that it was extreme in every way and lasted so long.

[SilverFallsAndrew]

The February 1989 blast brought very heavy snow to the Willamette Valley. Places like Bellingham and PDX just got blasted so hard with outflow they struggled to get accumulations. 

[Brian_in_Leavenworth]

3 minutes ago, paulb/eugene said:

This was the first Seattle AFD mentioning Feb 89

Fascinating.  Didnt know they had AFDs in 1989, considering there was no internet.  I do remember weather summaries over weather radio, but nothing like an AFD with the possibilities and various scenarios and forecasters reasoning for why they are forecasting what they are forecasting.

[SilverFallsAndrew]

https://climate.usu.edu/reports/e15daily.php?stn=USW00024232&year=1989&month=2&unit=EN&network=direct:ghcn&sidebar=0

[Gradient Keeper]

16 minutes ago, paulb/eugene said:

This was the first Seattle AFD mentioning Feb 89

The beloved MRF model! They loved those abbreviations back then didn't they? lol

[snow_wizard]

48 minutes ago, Brian_in_Leavenworth said:

As legendary as 1989 was, I think it would have disappointed a lot of people here.  IMHO, February 2019 was far better.  Though I think a lot of areas got snow, some areas did not.  I was in Bellingham, and just had a trace.  

The other thing people would have found disappointing was that it was a short lived event.  Bellingham and Seattle only had 4 days with highs below 32, and after that temps quickly got back to normal.  There was some snow in early March, but that was a separate event.

Portland stayed cool longer than Seattle, probably gorge winds kept it cool.  But it too only had about 4 days below freezing.  

The lows stayed cold for a long time though and snow was on the ground for quite a while.  The monthly average ended up super cold.

[snow_wizard]

36 minutes ago, Brian_in_Leavenworth said:

Well certainly it was unique as to how cold it was, and North Whatcom County had wind gusts over 100 MPH and several buildings hadn roofs blown off.  And wind chills there were about-60, though I know these days they have revised wind chill charts and the actual  wind chill was not as extreme as that.  

But I was left with a feeling of wanting more.  Not just more snow, but a longer event.  It just gradually warmed up and after about 5 days it was all over.   Rivers and large lakes did not have time to freeze over.

2008 was also better IMHO for the same reasons, plus there was a white Christmas.  Hard to beat that. Didnt have extreme winds, and not as cold, but it was amazing.  What makes January 1950 so great is that it was extreme in every way and lasted so long.

We did get more later on also.  I apparently have fonder memories of it than you do.

[fubario]

45 minutes ago, paulb/eugene said:

000 
TTAA00 KSEA 290957
LTL CHG IN BASIC PATRN OF STG W-E JET ALG 55N...HI HGTS OVR WA AND LTL
IF ANY PVA OR SIGNFNT S/WVS MVG THRU STATE. BAD STLT PICS POORLY SHW
BACLIN BAND ACRS VRISL MVG SLWLY SWD IN RSPNS TO CD UPR LO IN SRN AK
SO HIGHEST POPS AT UIL AND BLI. BACLIN BAND LIKELY TO STALL JUST N OF
WA. BIG QUESTION AFT 48 HRS IS HOW FAR S WILL CD UPR AK LO DROP. WILL
IT CONT TO DROP STRGT SWD TWD WA OR WILL IT STRT RTRGRTNG W BOUND AND
END UP UNDER BERING SEA BLK. THIS PUTS WA IN CONTD RDGG WITH ANTICYC
FLO. NEW RUN OF MRF SHLD SHED SM LIGHT ON THIS. ERN WA STUCK IN THE
SOUP HWVR BOTH NGM AND MRF INCRS THE SLY GRAD ACRS ERN WA ON MON SO
SE AND XTRM E PRTS COULD TMPRLY BRKOUT WITH MAX TMPS MVG UP SM. FOG
AND ST TDA WILL HOLD DWN MAX TMPS BLO WHAT MOS SAYS. INTERESTING TO
NOTE THAT BOTH NGM AND LFM DVLP 1072 MB ARCTIC HI IN ERN AK IN 48
HRS WHICH WOULD SHATTER THE PRVS N AMRCN RCRD HI PRES OF 1067.6 MB
SET ON JAN 1 1974 IN THE YUKON TERR. NEW 06Z MRF RUN JUST CAME IN
AND NEW 120 HR VALID 00Z FRI WILL KNOCK YOUR SOCKS OFF COMPARED TO PRVS
RDGG PATRN. REFUSE TO JUMP ON THIS UNTIL 2ND MRF RUN TNGT CONFIRMS
OR ELSE YO YOS BACK TO RDGG. MRF TYPICALLY POOR WITH BLKS SPLTS
AND NRN FLO S/WVS COMNG DWN FM AK. HWVR =IF CORRECT HANG ONTO YOUR
SOCKS. BC

we called the NGM the 'no good model' back in the day

[Brian_in_Leavenworth]

3 minutes ago, snow_wizard said:

We did get more later on also.  I apparently have fonder memories of it than you do.

We had virtually no snow in Bellingham.  I do have good memories of a decent snow in early March.  It was from a meteorological point of view very interesting.  But the Alaska records were even more interesting.  And I wonder how cold Whatcom would have been without the winds, especially once the cold air settled in.

Nighttime lows stayed relatively cool after the warmup, but it was clear every night and by then the wind had died down. 

[Rubus Leucodermis]

47 minutes ago, bainbridgekid said:

Fascinating. Also really cool to see how much AFD writing style has changed since then.

You have to remember that in 1989 the Internet was still a fairly esoteric thing that only researchers and academics used. There was no World Wide Web. Those weather discussions went out via wire services on leased lines, using a 5-bit character set that had no lowercase letters (hence the ALL CAPS) and slow speeds (hence abbreviations). Their audience was a tiny fraction of what the forecast discussion audience is today.

[Brian_in_Leavenworth]

6 minutes ago, Rubus Leucodermis said:

You have to remember that in 1989 the Internet was still a fairly esoteric thing that only researchers and academics used. There was no World Wide Web. Those weather discussions went out via wire services on leased lines, using a 5-bit character set that had no lowercase letters (hence the ALL CAPS) and slow speeds (hence abbreviations). Their audience was a tiny fraction of what the forecast discussion audience is today.

Who was their audience then?  TV forecasters?

[Rubus Leucodermis]

Just now, Brian_in_Leavenworth said:

Who was their audience then?  TV forecasters?

In part. Also researchers, other forecasters, etc.

[snow_wizard]

IMBY the 1989 event featured the following.  Jan 31 was included in this also.

8 consecutive highs below 40

15 consecutive days with 1" or more snow on the ground

17 consecutive lows of 30 or lower

extreme low of 5

Two max temps below 20

and a solid week of sunny and cold weather.  I always give high marks to events that have snow followed by clear and cold weather.

[snow_wizard]

1 hour ago, fubario said:

we called the NGM the 'no good model' back in the day

From what I could tell the NGM assumed no terrain at all.  It was kind of fascinating to see how things would play out if the mountains weren't there.  One thing I remember is surface gradients were shown as northerly in many cases that we would see easterly in reality, which of course would be much colder for Seattle with no down sloping.

[TT-SEA]

Looking further ahead in 1989 to April and May using the Snoqualmie Falls data... there was probably lots of teeth-gnashing about the incredibly dry weather and how all the trees are going to die and how it never used to be this dry in the spring!