PNW March 2023 Weather Discussion (2012 Redux)

[SilverFallsAndrew]

2 minutes ago, Phil said:

March-May every year.

Reminiscent of the late 2000s/early 2010s ECMWF tendency to put a cutoff ULL over the SW US. The next GFS upgrade in 2024/2025 should address this issue. I hope.

All in all, the next 2-3 weeks look to be a continuation of the pattern we have seen since mid-February. At least out here. 

[MossMan]

Tankage. 

[Phil]

14 minutes ago, SilverFallsAndrew said:

All in all, the next 2-3 weeks look to be a continuation of the pattern we have seen since mid-February. At least out here. 

Yeah looks like it. But I’m skeptical the cool/wet pattern will continue beyond mid-April. Lowpass constructed analogs converge to a much drier-looking pattern in W-Canada/PNW from mid/late April through mid/late May, while the Southwest/Interior West continue with a cool/wet theme (probably due to ULL activity associated with the STJ).

But it’s a very different pattern than those of the last few years at that stage. It was clear early-on in both 2021 and 2022 that the 4CH was going to be a beast heading into the warm season. Not the case this year.

[Doinko]

1 minute ago, Phil said:

Yeah looks like it. But I’m skeptical the cool/wet pattern will continue beyond mid-April. Lowpass constructed analogs converge to a much drier-looking pattern in W-Canada/PNW from mid/late April through mid/late May, while the Southwest/Interior West continue with a cool/wet theme (probably due to ULL activity associated with the STJ).

But it’s a very different pattern than those of the last few years at that stage. It was clear in both 2021 and 2022 that the 4CH was going to be a beast. Not the case this year.

Would that increase chances for thunderstorms here?

[snow_wizard]

Dry pattern for WA, BC, and less so for OR is locking in it would appear.

[Phil]

1 minute ago, Doinko said:

Would that increase chances for thunderstorms here?

I don’t know enough about PNW thunderstorm climatology to say one way or another.

[snow_wizard]

9 hours ago, Gradient Keeper said:

00z GEFS 10 Day Snowfall totals

If I could have a dollar for every inch it has shown for me since mid Feb I could go on a nice vacation.

[SilverFallsAndrew]

5 minutes ago, Phil said:

Yeah looks like it. But I’m skeptical the cool/wet pattern will continue beyond mid-April. Lowpass constructed analogs converge to a much drier-looking pattern in W-Canada/PNW from mid/late April through mid/late May, while the Southwest/Interior West continue with a cool/wet theme (probably due to ULL activity associated with the STJ).

But it’s a very different pattern than those of the last few years at that stage. It was clear early-on in both 2021 and 2022 that the 4CH was going to be a beast heading into the warm season. Not the case this year.

This makes sense. The pattern evolution is quite a bit different this year than last. We had a cold snap at the end of last February too, but it was more of a one off, March was fairly mild overall, the default troughing set up much later on. 

[snow_wizard]

47 minutes ago, SilverFallsAndrew said:

Today will likely be our last day of continuous snowcover too. That will be a 26 day streak as well. 2nd longest since I've been here. We went from Feb 3 - March 21 with continuous snow cover in 2019. Historically speaking the big snow years up here generally melt out around March 15-20th. 

2019 was like that up here too.  Places just north of me had continuous snow cover for a month at about 500 feet.  I was just barely too far south to really cash in that last big snow so it didn't last as long.

[Deweydog]

14 minutes ago, Phil said:

Yeah looks like it. But I’m skeptical the cool/wet pattern will continue beyond mid-April. Lowpass constructed analogs converge to a much drier-looking pattern in W-Canada/PNW from mid/late April through mid/late May, while the Southwest/Interior West continue with a cool/wet theme (probably due to ULL activity associated with the STJ).

But it’s a very different pattern than those of the last few years at that stage. It was clear early-on in both 2021 and 2022 that the 4CH was going to be a beast heading into the warm season. Not the case this year.

STRONG feeling that our cold July will be a rock solid case of delayed but NOT denied.

[snow_wizard]

1 minute ago, Deweydog said:

STRONG feeling that our cold July will be a rock solid case of delayed but NOT denied.

August is the month we haven't been able to buy a cool anomaly this century though.

[snow_wizard]

I think we may have hit the first peak of the solar cycle.  The last couple of days have had a lower sunspot number than any day since November.  On the last cycle the second peak was slightly higher than the first which is somewhat unusual.

We often have a loser winter or two just after the peak so my bets are on 2024-25 being a turd.  Interestingly the strongest solar max on record was in 1957, so that and the resultant El Nino is probably what brought an end to the amazing cold period we had in the late 1940s through 1957.

[SilverFallsAndrew]

2 minutes ago, snow_wizard said:

I think we may have hit the first peak of the solar cycle.  The last couple of days have had a lower sunspot number than any day since November.  On the last cycle the second peak was slightly higher than the first which is somewhat unusual.

We often have a loser winter or two just after the peak so my bets are on 2024-25 being a turd.  Interestingly the strongest solar max on record was in 1957, so that and the resultant El Nino is probably what brought an end to the amazing cold period we had in the late 1940s through 1957.

If we have a big late October cold snap this year then I'm throwing in the towel. If we get a dud I hope it's more like 2009-10 and not 2014-15. 

[Gradient Keeper]

12z GFS, GEM 10 Day Loop.
The GFS digs the trough offshore a bit, and the Canadian hammers us with one cold trough after another. WOW!

[TT-SEA]

More of a direct hit for western WA with the Thursday/Friday trough.   Even shows snow for my area... but also shows a south wind and temps above freezing during that time so I doubt it amounts to much.

[SilverFallsAndrew]

1 minute ago, TT-SEA said:

More of a direct hit for western WA with the Thursday/Friday trough.   Even shows snow for my area... but also shows a south wind and temps above freezing during that time so I doubt it amounts to much.

Looks like close to 6" here. This could be a solid late season EVENT. 

[SilverFallsAndrew]

EURO seems drier than the GEM and GFS after the first trough. It also shows lows into the mid-20s in the WV on Sunday and Monday. 

[TT-SEA]

High clouds are thinning... filtered sun and 61 now.

[MossMan]

2 minutes ago, TT-SEA said:

High clouds are thinning... filtered sun and 61 now.

Quite cloudy and 56 here. 

[T-Town]

25 minutes ago, TT-SEA said:

More of a direct hit for western WA with the Thursday/Friday trough.   Even shows snow for my area... but also shows a south wind and temps above freezing during that time so I doubt it amounts to much.

Tacoma C-zone?

[Cascadia_Wx]

Looks like PDX hit 60 for the 4th day in a row. Let’s hope we can put the overachieving warm spell thing to rest now and it doesn’t become the theme the next 6-7 months.

[snow_wizard]

The GFS and ECMWF both agree on daily averages dropping into the 8 to 10 below normal range later this week.  Should nicely round out a solidly cold March.

[Cold Snap]

35 minutes ago, TT-SEA said:

More of a direct hit for western WA with the Thursday/Friday trough.   Even shows snow for my area... but also shows a south wind and temps above freezing during that time so I doubt it amounts to much.

It would be nice to see one more event. I remember there was a nice little event on 3/22/13 that gave me an unexpected 1.5”. I remember the news saying it was going to snow but wasn’t going to really accumulate much but it ended up sticking to everything and I still had school that day and most of the buses ended up being 10+ minutes late because none of the roads were treated.

[SilverFallsAndrew]

8 minutes ago, Cascadia_Wx said:

Looks like PDX hit 60 for the 4th day in a row. Let’s hope we can put the overachieving warm spell thing to rest now and it doesn’t become the theme the next 6-7 months.

WOW! I did NOT see that coming! Different world down here. Light rain and 45. 

[snow_wizard]

I so hope we don't get a significant El Nino this year.  When we get on a cold roll like this it normally ends when a Nino knocks out the endless parade of GOA ridges.  High chance at least the early part of the next cold season will be very good if nothing upsets the apple cart.

[snow_wizard]

1 hour ago, SilverFallsAndrew said:

If we have a big late October cold snap this year then I'm throwing in the towel. If we get a dud I hope it's more like 2009-10 and not 2014-15. 

If there's a Nino I agree.  October cold waves are toxic in that case.  If it's neutral I think an October cold wave would be fine.

[Phil]

1 hour ago, snow_wizard said:

I think we may have hit the first peak of the solar cycle.  The last couple of days have had a lower sunspot number than any day since November.  On the last cycle the second peak was slightly higher than the first which is somewhat unusual.

We often have a loser winter or two just after the peak so my bets are on 2024-25 being a turd.  Interestingly the strongest solar max on record was in 1957, so that and the resultant El Nino is probably what brought an end to the amazing cold period we had in the late 1940s through 1957.

Doubt we’ve hit the peak since the mean polar field/IMF hasn’t flipped yet (just the south pole). Maybe a year or two from maximum?

[snow_wizard]

The MJO forecast is more bullish on the current wave staying strong over the Indian Ocean with each run.  Good sign for upsetting the development of any possible Nino.

[snow_wizard]

2 minutes ago, Phil said:

Doubt we’ve hit the peak since the mean polar field/IMF hasn’t flipped yet (just the south pole). Maybe a year or two from maximum?

I think we might see a case where the second peak is the highest again....like the last cycle.

[Phil]

4 minutes ago, snow_wizard said:

I so hope we don't get a significant El Nino this year.  When we get on a cold roll like this it normally ends when a Nino knocks out the endless parade of GOA ridges.  High chance at least the early part of the next cold season will be very good if nothing upsets the apple cart.

Well that explains why you’re so adamantly against one.

FWIW, it’s more likely to be an average/moderate event as opposed to a strong/super niño. We will know a *lot* more during/after the next MJO transit in mid/late April (which should also coincide with a flip to a warmer pattern in the NW, if all goes to plan).

[Phil]

8 minutes ago, snow_wizard said:

The MJO forecast is more bullish on the current wave staying strong over the Indian Ocean with each run.  Good sign for upsetting the development of any possible Nino.

Actually the stronger the MJO is during the EHEM transit, the stronger it will be coming out of the IO/IPWP, and thus will produce a stronger WWB/greater disruption of the Walker Cell, increasing the odds for a stronger El Niño.

The vigorous MJO response to SSW/MC acceleration is what killed the La Niña regime.

[Phil]

8 minutes ago, snow_wizard said:

I think we might see a case where the second peak is the highest again....like the last cycle.

Definitely possible. Though I’m not a solar physicist so my opinion isn’t worth much.

[Cascadia_Wx]

14 minutes ago, SilverFallsAndrew said:

WOW! I did NOT see that coming! Different world down here. Light rain and 45. 

Now looking like one cool day tomorrow then they are in the low 60s again Tuesday/Wednesday. What happened to our cold month Andrew!?

[SilverFallsAndrew]

5 minutes ago, Cascadia_Wx said:

Now looking like one cool day tomorrow then they are in the low 60s again Tuesday/Wednesday. What happened to our cold month Andrew!?

Well, we should end up below normal, but most areas that didn't have 3 weeks of snow cover will not be in the top 10 for cold Marches. Oh well, such is lyfe in a rapidly warming klimate. 

[SilverFallsAndrew]

Could see some cold lows over the weekend and early next week. Of course that won't impact PDX as much, if they do achieve a freeze it will likely be the last one of the season inside the urban core. 

[Cascadia_Wx]

7 minutes ago, SilverFallsAndrew said:

Well, we should end up below normal, but most areas that didn't have 3 weeks of snow cover will not be in the top 10 for cold Marches. Oh well, such is lyfe in a rapidly warming klimate. 

Maybe we’re just not ready 2 be luved Andrew 

https://youtu.be/krdQLzzAeZU

 

[TigerWoodsLibido]

51F with some light rain.

[Cascadia_Wx]

Did some digging and as of today PDX is still tied for the 4th coldest March on record (average temp of 43.8, tied with 1954 and 1964). Of course there are still 13 days to go.

They would have to stay below 44.7 for an average temp to end up with a top ten coldest March. Seems like a long shot but the 3-10 day period is looking pretty chilly on the Euro…

[Cascadia_Wx]

If they did it it would be their first top ten cold March since 1976. We’ve had a lot of chilly Marches in recent years but nothing really top tier.

[Meatyorologist]

2 hours ago, Doinko said:

Would that increase chances for thunderstorms here?

Effectively, yeah. Lots of vorticity and differential winds associated with cutoffs. And they are by definition divorced from the jet stream, so they can meander into warmer/moister airmasses and spark thunderstorms where there are better dynamics.

[SilverFallsAndrew]

2 minutes ago, Cascadia_Wx said:

If they did it it would be their first top ten cold March since 1976. We’ve had a lot of chilly Marches in recent years but nothing really top tier.

Good stuff. Seems largely a function of UHI. Takes an act of the GODS to pull off a cold low at PDX these days. 

[Cascadia_Wx]

1 minute ago, SilverFallsAndrew said:

Good stuff. Seems largely a function of UHI. Takes an act of the GODS to pull off a cold low at PDX these days. 

SLE has taken a pretty hard turn down that path as well in recent decades.

[SilverFallsAndrew]

1 minute ago, Cascadia_Wx said:

SLE has taken a pretty hard turn down that path as well in recent decades.

Oh absolutely. The price of PROGRESS.

[Meatyorologist]

4 minutes ago, SilverFallsAndrew said:

Good stuff. Seems largely a function of UHI. Takes an act of the GODS to pull off a cold low at PDX these days. 

...blessings?

[Deweydog]

Petrichor!

[Gradient Keeper]

12z Euro 10 Day Loop: 500mb Height Anomaly, 850mb Temps. Snow maps are just eye candy.

In this pattern featuring cold onshore flow sticking snow is unlikely below around 1000' to maybe 700'. For us measly lowlanders we could see wet snow and slushy stuff on the trees, yards, and vehicles during the overnight and to around 8-9 AM.

[FroYoBro]

Life giving liquid is taking from the skies. Thank you Gaia!

[Cold Snap]

I think it’s very possible I’m going to be adding even more to my freeze total this coming weekend.

[MossMan]

Going through my video archives it appears we had some late season snow back on March 24th 2018 at our old place which was at 300’. 

[SilverFallsAndrew]

16 minutes ago, MossMan said:

Going through my video archives it appears we had some late season snow back on March 24th 2018 at our old place which was at 300’. 

IMG_4433.MOV

That was a huge storm down this way.