December 2022 Forecasts And Discussions

[John]

They did in December 68 and January 69 John.

Probably some model runs back then said it would be -50 at yvr but moderated to -20

[Typeing3]

18z completely different again cold slides east still the most likely outcome imo

Eh. GFS has been pretty inconsistent lately. Best to look at the trends on the ECMWF instead.

Most likely outcome is to see moderation as we get within closer range. That always happens.

[VanCitySouth]

Also has this
gfs_mslp_pcpn_frzn_nwus_31.png

That's an other way to get . I think Nito will stay at bay.
gfs_T850_nwus_32.png

In my defence, it was a lot less cold at 120 hours.

[John]

Eh. GFS has been pretty inconsistent lately. Best to look at the trends on the ECMWF instead.

Consistent or realistic?

[PortKells]

Most likely I said, there is also climo to consider
extreme model runs have never verified

It will definitely moderate of course. But its not all going to slide east, based on the GFS anyways. If the real models show an easterly trend later then yes, its probably going to slide east.

[Typeing3]

Consistent or realistic?

ECMWF

Day 5 (Saturday morning) -- past three 12z runs trend.

ec-fast_T850_nwus_fh120_trend.gif

Day 6 (Sunday morning) -- last three 12z runs trend.

ec-fast_T850_nwus_fh144_trend.gif

[HarrisonSasquatchWx]

Probably some model runs back then said it would be -50 at yvr but moderated to -20

perhaps yes.

[tyweather]

With cold weather forecasted (including chilly weather this week) and December still averaging below 0c for the mean it looks like Agassiz could have an average mean temperature 0c or below for this month. If it does then this will be the 2nd year in a row to achieve an average mean 0c or below and only the 4th time since 1996 to do so. There was a 20 year gap between 1996 and 2016 where Agassiz didn't have a monthly mean average below 0c. (Dec 2008 average just above 0 at 0.3c).

[Typeing3]

With cold weather forecasted (including chilly weather this week) and December still averaging below 0c for the mean it looks like Agassiz will likely have an average mean temperature 0c or below for this month. This will be the 2nd year in a row to achieve an average mean 0c or below and only the 4th time since 1996 to do so. There was a 20 year gap between 1996 and 2016 where Agassiz didn't have a monthly mean average below 0c. (Dec 2008 average just above 0 at 0.3c).

Nice graph! Can you also post it in the thread below so they don't get lost here.

https://forums.bcstorms.ca/viewtopic.php?f=201&t=1491

[Storm]

I say we wait for the 18z EPS

[Bonovox]

The theme this winter has been to slide the trough too far SW. That is something to watch on the Euro, but I don’t get that feeling this time around. The block seems to be strong enough to shunt more of the energy in a N-S orientation than NE-SW.

[VanCitySouth]

The theme this winter has been to slide the trough too far SW. That is something to watch on the Euro, but I don’t get that feeling this time around. The block seems to be strong enough to shunt more of the energy in a N-S orientation than NE-SW.

I wonder why it is that the atmosphere seems to get into these rinse and repeat patterns which feel very difficult to dislodge.

[Bonovox]

I wonder why it is that the atmosphere seems to get into these rinse and repeat patterns which feel very difficult to dislodge.

It is fascinating, but way beyond my level of comprehension.

[Typeing3]

I wonder why it is that the atmosphere seems to get into these rinse and repeat patterns which feel very difficult to dislodge.

I remember reading this a long ways back.

https://stormtrack.org/community/thread ... her.15932/

The Lezak's Recurring Cycle (or LRC) is a theory developed by Gary Lezak. Gary noticed back in the 1980s that storm systems seemed to have similar characteristics unique to that year. Quite simply a storm in February looked very similar to one that had occured earlier in that season, say in December. As the years went by Gary started paying closer attention to the weather patterns and he came up with the LRC.


The LRC (Lezak's Recurring Cycle)​

[*]A unique weather pattern sets up every autumn between October 1st and November 10th
[*]"Long term" longwave troughs and ridges become established over the northern hemisphere
[*]The pattern cycles and repeats over and over again until it slowly weakens and falls apart during the mid summer months

[HarrisonSasquatchWx]

When did E.C. throw flurries into the central valley forecast it wasn't there @ 5a.m. colder to now.