Jump to content

Welcome!

Sign In or Register to gain full access to our forums. By registering with us, you'll be able to discuss, share and private message with other members of our community.

Welcome!

Thanks for stopping by the Weather Forums! Please take the time to register and join our community. Feel free to post or start new topics on anything related to the weather or the climate.


Photo

Fall and Winter 2019-20 Predictions and Discussion

- - - - -

  • Please log in to reply

#201
Phil

Posted 22 October 2019 - 05:06 PM

Phil

    Forum Fantastic

  • Members
  • PipPipPipPipPipPipPipPip
  • 27440 posts
  • LocationCabin John, MD.


Rough idea from now through the first half of winter.

- November (2nd half) and January are the months with the highest likelihood of productive patterns for arctic cold and lowland snow, in my opinion. December probably has the least likelyhood of producing a favorable pattern for the West. Not sure about February yet..could go either way.

- Likely a +ENSO winter, either warm neutral or weak modoki niño, but whether it meets that official definition or not is largely irrelevant.

- A legit MJO event should gather in the IO around/just after Halloween (after the -SAM peaks) and cross the IPWP/Pacific during 2nd/3rd week of November. Watch for an Alaskan wavebreak around November 12th-18th culminating in an Arctic outbreak for much of the West-Central US. Whether it affects the PNW remains to be seen, of course, but it could be a legit blast.

- December looks like a more -EPO dominant version of 2009, IMO, with cold mostly focused in the East with a +PNA/western ridge for much of the month. More subsidence over the Maritime Continent and coinciding EAMT event like recently, but with the seasonal changes the response will probably be more niño-ish.

- January is when things get interesting. Less certain at this range, but there are conduits to a retrogression and legitimate -PNA/-EPO pattern and Arctic outbreak with a huge mass of cold likely residing on our side of the pole initially thanks to the dominating -EPO/torques. If intraseasonal forcings can overpower the background state (might need some stratospheric help)...watch out.

- Not sure about February yet. I could see it going either way but I’ll lean to the colder side for now.


FWIW, that blocking episode will probably start closer to November 18th than November 12th. Slower intraseasonal recycle has been the theme these year.

Precursory MJO wave looks on target so far.
Winter 2019/20
Winter events: 3 (11/16, 12/11, 12/16)
Total snowfall: 1.1”
Coldest temp: 21.4*F (11/14)
Highest Gust: 54mph (11/27)
Personal Weather Station Live Stream
NOAA: https://www.wrh.noaa...168&banner=NONE
Wunderground: https://www.wundergr...019-08-23/daily

#202
Phil

Posted 22 October 2019 - 05:08 PM

Phil

    Forum Fantastic

  • Members
  • PipPipPipPipPipPipPipPip
  • 27440 posts
  • LocationCabin John, MD.

Here it is guys.

November:
Temps: Near Average
Precip: Slightly below average
Snowfall/pack: No lowland snow south of Everett, slight chance north. Snow pack average to below.

December
Temps: Well above average
Precip: Near normal to slightly above.
Snowfall/pack: Slight chance late month south of Olympia, 30-40% odds of accumulating snow late month north of Olympia. Snow pack near to below average.

January
Temps: Near average/slightly above. Wildcare with temps is a stronger than normal chance of an inversion pattern early in the month. Slight chance of modified arctic air early in the month.
Precip: Near normal
Snowfall/pack: 50/50 odds of minor snowfall early in the month Seattle north. Slight chance of accumulating snow south of Seattle early in the month. Snow pack below average.

February
Temps: Well above average
Precip: Below average
Snowfall/pack: No lowland snow, well below normal mountain snow pack.

Overall
Temps: Temps will be above normal for the late November-February period. Potentially the warmest winter since 2014-15. Odds are we go another winter without a major regional outbreak, though at least a modified outbreak in the early January timeframe, or even a short duration regional blast would not entirely surprise me.
Precip: A greater than even chance precip is below normal to near normal during the period.
Snowfall/snow pack: I would give better than even odds there is no accumulating snow south of Portland. About even odds that PDX has a minor snow event, and about 70% odds Seattle at least sees one minor accumulation. Best odds in the PNW lowlands are in the NW interior as a January 2005 type event is definitely not out of the question. Mountain snow pack will likely disappoint.

BLI: 6"
Sea: 3"
PDX: 1.5"
SLE: 0
EUG: 0


Surprised how bearish you went.

With all the “OMG NINO” flack I get, your forecast is much warmer than mine, lol.
  • Omegaraptor likes this
Winter 2019/20
Winter events: 3 (11/16, 12/11, 12/16)
Total snowfall: 1.1”
Coldest temp: 21.4*F (11/14)
Highest Gust: 54mph (11/27)
Personal Weather Station Live Stream
NOAA: https://www.wrh.noaa...168&banner=NONE
Wunderground: https://www.wundergr...019-08-23/daily

#203
Front Ranger

Posted 22 October 2019 - 06:07 PM

Front Ranger

    Very Special and Incredibly Advanced Contributor

  • Members
  • PipPipPipPipPipPipPipPip
  • 20630 posts
  • LocationWestminster, CO

The thing with solar is there’s both physical and statistical evidence to suggest it affects blocking/wavetrains and even ENSO/tropical convection via a direct manipulation of static stability across the deep tropics.

Problem is, that effect could vary significantly depending on initial boundary conditions. So the nature/structure of the high latitude blocking might not be the same from one solar minimum to the next.

For instance, the effect of the 11yr solar cycle in the 1950s/60s was certainly not the same as it is now. But it was clearly detectable (statistically and possibly dynamically upon reconstruction) via numerous parameters.


I think it's worth mentioning the overall solar activity was also significantly higher in the 1950s/1960s.

Low. Solar.


#204
GHweatherChris

Posted 22 October 2019 - 06:15 PM

GHweatherChris

    Special Contributor

  • Members
  • PipPipPipPipPipPipPip
  • 6275 posts
  • LocationAberdeen, WA (7 miles east)

I think it's worth mentioning the overall solar activity was also significantly higher in the 1950s/1960s.


Was solar activity measured the same way back then as it is now? I have no clue, just curious.

#205
Front Ranger

Posted 25 October 2019 - 01:20 PM

Front Ranger

    Very Special and Incredibly Advanced Contributor

  • Members
  • PipPipPipPipPipPipPipPip
  • 20630 posts
  • LocationWestminster, CO
Here are my thoughts going forward.

- Much greater -AO/-NAO than last winter
- North Pacific blocking regime we have seen this fall should continue to be dominant, though it will shift more over Western Canada at times, especially mid January on
- eastern 1/3 of the country will be much colder Jan-Mar this winter
- November should see cold centered over the central part of the country
- Early December to early January is best window for major cold/snow events in PNW
- Highly elevated chance of top tier cold across the entire US, due to persistent and strong high latitude blocking, weak jet
- Precipitation is highly unpredictable, but the west coast should see extended dry periods punctuated by heavy rain/snow events and strong storms
- First half of winter should tend more -PNA, second half more +PNA
- This will be an anomalously snowy winter for many regions
- Overall, it would not surprise me if 2019-20 is a top 5 coldest winter for the past 50+ years in the US
- That being said, extreme swings in temperature will be common, especially for the middle of the country and southern sections
  • Phil, Chris, snow_wizard and 1 other like this

Low. Solar.


#206
Phil

Posted 25 October 2019 - 01:28 PM

Phil

    Forum Fantastic

  • Members
  • PipPipPipPipPipPipPipPip
  • 27440 posts
  • LocationCabin John, MD.

Here are my thoughts going forward.

- Much greater -AO/-NAO than last winter
- North Pacific blocking regime we have seen this fall should continue to be dominant, though it will shift more over Western Canada at times, especially mid January on
- eastern 1/3 of the country will be much colder Jan-Mar this winter
- November should see cold centered over the central part of the country
- Early December to early January is best window for major cold/snow events in PNW
- Highly elevated chance of top tier cold across the entire US, due to persistent and strong high latitude blocking, weak jet
- Precipitation is highly unpredictable, but the west coast should see extended dry periods punctuated by heavy rain/snow events and strong storms
- First half of winter should tend more -PNA, second half more +PNA
- This will be an anomalously snowy winter for many regions
- Overall, it would not surprise me if 2019-20 is a top 5 coldest winter for the past 50+ years in the US
- That being said, extreme swings in temperature will be common, especially for the middle of the country and southern sections


Interesting. Will be interesting to watch this one unfold given the change to elements the background state relative to recent years.

FWIW I largely agree, though I’m more bearish on December in the West this year.
Winter 2019/20
Winter events: 3 (11/16, 12/11, 12/16)
Total snowfall: 1.1”
Coldest temp: 21.4*F (11/14)
Highest Gust: 54mph (11/27)
Personal Weather Station Live Stream
NOAA: https://www.wrh.noaa...168&banner=NONE
Wunderground: https://www.wundergr...019-08-23/daily

#207
BLI snowman

Posted 25 October 2019 - 02:53 PM

BLI snowman

    Lacking H20

  • Members
  • PipPipPipPipPipPipPip
  • 9537 posts
  • LocationRidgefield, WA

Late January is still really, really due out here.



#208
Deweydog

Posted 25 October 2019 - 03:23 PM

Deweydog

    Forum Fantastic

  • Banned
  • PipPipPipPipPipPipPipPip
  • 23693 posts
  • LocationHockinson, WA

Late January is still really, really due out here.


Cool it with the MLK stuff, dude. Not cool.
All roads lead to Walgreens.

#209
BLI snowman

Posted 25 October 2019 - 03:42 PM

BLI snowman

    Lacking H20

  • Members
  • PipPipPipPipPipPipPip
  • 9537 posts
  • LocationRidgefield, WA

Cool it with the MLK stuff, dude. Not cool.

 

Australia Day.



#210
snow_wizard

Posted 25 October 2019 - 05:32 PM

snow_wizard

    The Snow Wizard

  • Mods
  • 17684 posts
  • LocationCovington, WA

Here are my thoughts going forward.

- Much greater -AO/-NAO than last winter
- North Pacific blocking regime we have seen this fall should continue to be dominant, though it will shift more over Western Canada at times, especially mid January on
- eastern 1/3 of the country will be much colder Jan-Mar this winter
- November should see cold centered over the central part of the country
- Early December to early January is best window for major cold/snow events in PNW
- Highly elevated chance of top tier cold across the entire US, due to persistent and strong high latitude blocking, weak jet
- Precipitation is highly unpredictable, but the west coast should see extended dry periods punctuated by heavy rain/snow events and strong storms
- First half of winter should tend more -PNA, second half more +PNA
- This will be an anomalously snowy winter for many regions
- Overall, it would not surprise me if 2019-20 is a top 5 coldest winter for the past 50+ years in the US
- That being said, extreme swings in temperature will be common, especially for the middle of the country and southern sections

 

I agree with most of this.  Good work!

 

I think there is a somewhat realistic shot at this being a top 10% cold winter for the NW based on what we have been seeing and solar.


Death To Warm Anomalies!

 

Winter 2019-20 stats

 

Total Snowfall = 2.8"

Day with 1" or more snow depth = 3

Total Hail = T

Coldest Low = 20

Lows 32 or below = 34

Highs 32 or below = 0

Lows 20 or below = 1

Highs 40 or below = 7

 

 


#211
snow_wizard

Posted 25 October 2019 - 05:35 PM

snow_wizard

    The Snow Wizard

  • Mods
  • 17684 posts
  • LocationCovington, WA

I considered years like 85-86, 71-72 specifically, but ultimately I think we will diverge from those paths. 77-78 may be an possible anolog. My primaries are 2004-05, 2012-13, 1969-70. I really like the 1969-70 analog. That would be a wetter year. 

My secondary analogs would probably be 1959-60, 1980-81, 1977-78, 1985-86.


I'm not a huge believer in considering solar.

 

I think Pete Parsons at the Oregon Department of Agriculture has some good analogs, I would say I used somewhat similar methodology.

 

Why are you choosing mostly Nino years?  I think your forecast is extremely pessimistic and has little chance of verifying, but we'll see.


Death To Warm Anomalies!

 

Winter 2019-20 stats

 

Total Snowfall = 2.8"

Day with 1" or more snow depth = 3

Total Hail = T

Coldest Low = 20

Lows 32 or below = 34

Highs 32 or below = 0

Lows 20 or below = 1

Highs 40 or below = 7

 

 


#212
snow_wizard

Posted 25 October 2019 - 05:38 PM

snow_wizard

    The Snow Wizard

  • Mods
  • 17684 posts
  • LocationCovington, WA

Was solar activity measured the same way back then as it is now? I have no clue, just curious.

 

Yes....they have standardized everything.  They only counted spots prior to the 1950s or so.  The fluxes, AP, and other metrics are much newer.  From spots alone it appears this is the quietest the sun has been in about 200 years.


Death To Warm Anomalies!

 

Winter 2019-20 stats

 

Total Snowfall = 2.8"

Day with 1" or more snow depth = 3

Total Hail = T

Coldest Low = 20

Lows 32 or below = 34

Highs 32 or below = 0

Lows 20 or below = 1

Highs 40 or below = 7

 

 


#213
GHweatherChris

Posted 25 October 2019 - 05:41 PM

GHweatherChris

    Special Contributor

  • Members
  • PipPipPipPipPipPipPip
  • 6275 posts
  • LocationAberdeen, WA (7 miles east)

Yes....they have standardized everything. They only counted spots prior to the 1950s or so. The fluxes, AP, and other metrics are much newer. From spots alone it appears this is the quietest the sun has been in about 200 years.


What evidence is there that sunspots were observed 200 years ago?

#214
Deweydog

Posted 25 October 2019 - 06:06 PM

Deweydog

    Forum Fantastic

  • Banned
  • PipPipPipPipPipPipPipPip
  • 23693 posts
  • LocationHockinson, WA
I was heading west on Highway 14 this evening and the solar seemed pretty d**n strong to me. Sunglasses and visor were deployed out of necessity.
All roads lead to Walgreens.

#215
Phil

Posted 25 October 2019 - 08:34 PM

Phil

    Forum Fantastic

  • Members
  • PipPipPipPipPipPipPipPip
  • 27440 posts
  • LocationCabin John, MD.

Why are you choosing mostly Nino years? I think your forecast is extremely pessimistic and has little chance of verifying, but we'll see.


Because the system state is closer to that of an El Niño that a La Niña? There should be no La Niña analogs used this winter, period.
Winter 2019/20
Winter events: 3 (11/16, 12/11, 12/16)
Total snowfall: 1.1”
Coldest temp: 21.4*F (11/14)
Highest Gust: 54mph (11/27)
Personal Weather Station Live Stream
NOAA: https://www.wrh.noaa...168&banner=NONE
Wunderground: https://www.wundergr...019-08-23/daily

#216
snow_wizard

Posted 25 October 2019 - 09:35 PM

snow_wizard

    The Snow Wizard

  • Mods
  • 17684 posts
  • LocationCovington, WA

What evidence is there that sunspots were observed 200 years ago?

 

The graphs are available online.  They actually go back more than 200 years.


Death To Warm Anomalies!

 

Winter 2019-20 stats

 

Total Snowfall = 2.8"

Day with 1" or more snow depth = 3

Total Hail = T

Coldest Low = 20

Lows 32 or below = 34

Highs 32 or below = 0

Lows 20 or below = 1

Highs 40 or below = 7

 

 


#217
snow_wizard

Posted 25 October 2019 - 09:38 PM

snow_wizard

    The Snow Wizard

  • Mods
  • 17684 posts
  • LocationCovington, WA

Because the system state is closer to that of an El Niño that a La Niña? There should be no La Niña analogs used this winter, period.

 

Warm neutral seems reasonable.  Historically a very good ENSO state for us.  It's really a stretch to call this Ninoish.  Right now the MJO is in Nina territory.  This is classic neutral.  As I pointed out before the all important OLR 160W to 160E is actually Ninaish right now and has been for a while.  We have serious mixed signals.


Death To Warm Anomalies!

 

Winter 2019-20 stats

 

Total Snowfall = 2.8"

Day with 1" or more snow depth = 3

Total Hail = T

Coldest Low = 20

Lows 32 or below = 34

Highs 32 or below = 0

Lows 20 or below = 1

Highs 40 or below = 7

 

 


#218
Phil

Posted 26 October 2019 - 10:44 AM

Phil

    Forum Fantastic

  • Members
  • PipPipPipPipPipPipPipPip
  • 27440 posts
  • LocationCabin John, MD.

Warm neutral seems reasonable. Historically a very good ENSO state for us. It's really a stretch to call this Ninoish. Right now the MJO is in Nina territory. This is classic neutral. As I pointed out before the all important OLR 160W to 160E is actually Ninaish right now and has been for a while. We have serious mixed signals.


Except it’s not..

The strongest positive OLR anomalies have been located over the Maritime continent, with the lowest OLR anomalies over the WHEM/EPAC. The reason there have been so many positive OLR anomalies from 100E to 150W this autumn is because the Walker Circulation has been much weaker than normal, which has reduced uplift over the IPWP domain. This is partially due to the super +IOD (which may have climaxed..we’ll have to see).

Again, it’s about the *spatial distribution* of the anomalies, relatively speaking. Not their values..it matters where they are occurring relative to one another and where the gradients are.
Winter 2019/20
Winter events: 3 (11/16, 12/11, 12/16)
Total snowfall: 1.1”
Coldest temp: 21.4*F (11/14)
Highest Gust: 54mph (11/27)
Personal Weather Station Live Stream
NOAA: https://www.wrh.noaa...168&banner=NONE
Wunderground: https://www.wundergr...019-08-23/daily

#219
Front Ranger

Posted 26 October 2019 - 01:25 PM

Front Ranger

    Very Special and Incredibly Advanced Contributor

  • Members
  • PipPipPipPipPipPipPipPip
  • 20630 posts
  • LocationWestminster, CO
Wxstatman is gonna have a ton of write-ups to do after this fall/winter. :)
  • Kayla likes this

Low. Solar.


#220
Guest_CulverJosh_*

Posted 27 October 2019 - 02:06 PM

Guest_CulverJosh_*
  • Guests
Kyle Dittmer has real data as it pertains to sunspots and La Nina...PNW weather

#221
snow_wizard

Posted 27 October 2019 - 07:13 PM

snow_wizard

    The Snow Wizard

  • Mods
  • 17684 posts
  • LocationCovington, WA

Wxstatman is gonna have a ton of write-ups to do after this fall/winter. :)

 

I think you're right.


Death To Warm Anomalies!

 

Winter 2019-20 stats

 

Total Snowfall = 2.8"

Day with 1" or more snow depth = 3

Total Hail = T

Coldest Low = 20

Lows 32 or below = 34

Highs 32 or below = 0

Lows 20 or below = 1

Highs 40 or below = 7

 

 


#222
Chris

Posted 30 October 2019 - 11:17 AM

Chris

    Community Mod

  • Admin
  • 1302 posts
  • LocationOregon Coast Range 1000'

I’ve finally had time to catch up with things today. And unless I’m flat out wrong about everything, I continue to favor the idea of prolific cold into the USA through the first half of winter at least, with a few relaxations, of course.

I still favor a major blocking episode in late November, following the mid-month relaxation/jet extension. It is still uncertain whether it will affect the PNW or slide east ahead of a niño-ish December, but either way this isn’t too relevant IMO, as January looks to have the highest potential, should all the pieces align.

In the ideal case, the strongest blocking since the last solar minimum begins around New Years. Big cold shot into the country during the first half of the month with an Archambault NAO progression and subsequent EPO retrogression and Arctic intrusion across NW-North America thereafter. Doesn’t have to be this extreme..but this isn’t some far-fetched weenie dream either.



#223
Front Ranger

Posted 09 November 2019 - 12:03 PM

Front Ranger

    Very Special and Incredibly Advanced Contributor

  • Members
  • PipPipPipPipPipPipPipPip
  • 20630 posts
  • LocationWestminster, CO

After several record-breaking cold air masses across the West the past 6 weeks, now it's the East's turn: https://www.washingt...vely-cold-snap/


Low. Solar.


#224
Phil

Posted 09 November 2019 - 12:38 PM

Phil

    Forum Fantastic

  • Members
  • PipPipPipPipPipPipPipPip
  • 27440 posts
  • LocationCabin John, MD.

After several record-breaking cold air masses across the West the past 6 weeks, now it's the East's turn: https://www.washingt...vely-cold-snap/


It was chilly this morning (21*F @ IAD was the coldest this early since the 19*F in 1976) but unless we can decouple next week, it’ll be tough to beat the numbers Nov 2014 eventually put up.

We suck at early season cold more than most places, so I’m always bearish until the winter solstice.
Winter 2019/20
Winter events: 3 (11/16, 12/11, 12/16)
Total snowfall: 1.1”
Coldest temp: 21.4*F (11/14)
Highest Gust: 54mph (11/27)
Personal Weather Station Live Stream
NOAA: https://www.wrh.noaa...168&banner=NONE
Wunderground: https://www.wundergr...019-08-23/daily

#225
Front Ranger

Posted 09 November 2019 - 12:44 PM

Front Ranger

    Very Special and Incredibly Advanced Contributor

  • Members
  • PipPipPipPipPipPipPipPip
  • 20630 posts
  • LocationWestminster, CO

It was chilly this morning (21*F @ IAD was the coldest this early since the 19*F in 1976) but unless we can decouple next week, it’ll be tough to beat the numbers Nov 2014 eventually put up.

We suck at early season cold more than most places, so I’m always bearish until the winter solstice.

 

I didn't realize that was so impressive in your area. Definitely one of the most anomalous cold air masses in recent decades, and affected a huge area.


  • Phil likes this

Low. Solar.


#226
Phil

Posted 08 December 2019 - 11:14 AM

Phil

    Forum Fantastic

  • Members
  • PipPipPipPipPipPipPipPip
  • 27440 posts
  • LocationCabin John, MD.
🤷‍♂️

I honestly don’t know yet. Probably leaning drier than normal with a weaker jet but that could favor a colder outcome as well.


The only aspect I’m (somewhat) confident about right now is a drier than normal winter overall, or a background state that is of the meridional/weak jet type. I suppose a strong intraseasonal MJO/AAM cycle could wreak havoc on that prediction, but I have to lean dry right now.

Haven’t decided on temperatures yet..depends on a number of processes that have yet to fully evolve/tip their hand.


Winter 2019/20
Winter events: 3 (11/16, 12/11, 12/16)
Total snowfall: 1.1”
Coldest temp: 21.4*F (11/14)
Highest Gust: 54mph (11/27)
Personal Weather Station Live Stream
NOAA: https://www.wrh.noaa...168&banner=NONE
Wunderground: https://www.wundergr...019-08-23/daily

#227
Deweydog

Posted 08 December 2019 - 11:19 AM

Deweydog

    Forum Fantastic

  • Banned
  • PipPipPipPipPipPipPipPip
  • 23693 posts
  • LocationHockinson, WA

🤷‍♂️



😱
All roads lead to Walgreens.

#228
Jesse

Posted 27 December 2019 - 12:59 PM

Jesse

    Forum Fantastic

  • Members
  • PipPipPipPipPipPipPipPip
  • 35432 posts
  • LocationEast Vancouver, WA (300')

Right now we seem to be set up pretty well for some early season action in November or December. Beyond that, who knows. If November or December ends up ridgy or warmer than expected there’s a chance winter will try to make a comeback in January but it’s hard telling not knowing. Probably a drier than average winter for most of the region if the blockiness keeps up, mountain snowpack could be near average though if the balance of the storms end up colder than usual.


😏
  • Phil likes this

#229
Phil

Posted 27 December 2019 - 01:49 PM

Phil

    Forum Fantastic

  • Members
  • PipPipPipPipPipPipPipPip
  • 27440 posts
  • LocationCabin John, MD.
I had a warm western December forecasted, however that TPV entrapment over the Beaufort f**ked me silly. Very fluky..would never have seen it (and I will almost certainly miss it again if this happens in the future).

Was expecting -EPO/+PNA for December. Instead it ended up being +EPO/+PNA. 🤷‍♂️
Winter 2019/20
Winter events: 3 (11/16, 12/11, 12/16)
Total snowfall: 1.1”
Coldest temp: 21.4*F (11/14)
Highest Gust: 54mph (11/27)
Personal Weather Station Live Stream
NOAA: https://www.wrh.noaa...168&banner=NONE
Wunderground: https://www.wundergr...019-08-23/daily