December 2020 Forecasts and Discussions

Weather reports, analysis etc. pertaining to Southern BC.
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wetcoast91
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Re: December 2020 Forecasts and Discussions

Post by wetcoast91 »

Monty wrote: Wed Dec 16, 2020 8:13 am Pretty chilly trough next week with a weak continental High sliding south in the interior. Energy remains split and all the moisture slides south. But it would be frosty.

A3E1DEA6-0DE1-45E1-B33F-D833D807BB2C.png
Always prone to seeing something pop up in those trough axis. Curvature vortices aloft and decent shear below 6km leads me to believe we could see some instability towards the Valley and SW Vancouver Island. Don't see anything that poses a threat right now but that could change.

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Re: December 2020 Forecasts and Discussions

Post by Rubus_Leucodermis »

Looks like Team 10ËšC Rain is going to notch another win today.
It's called clown range for a reason.
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Re: December 2020 Forecasts and Discussions

Post by PortKells »

A classic wet blanket gfs run. Ensembles more important anyways.
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Re: December 2020 Forecasts and Discussions

Post by Rubus_Leucodermis »

Catnip wrote: Wed Dec 16, 2020 9:05 am I still have the feeling that something could "pop up" in the models with not too much warning, but I :dunno:

I could be wrong.
Same feeling here. Model accuracy is never very good more than a week out, and it’s really been crap since the pandemic reduced the amount of data coming from commercial aircraft. There’s still over two full weeks of December left.
It's called clown range for a reason.
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Re: December 2020 Forecasts and Discussions

Post by wetcoast91 »

Overall a big step back on the 12z runs for any cold. Canadian is wet and mild. GFS is mild, drier but no signs of blocking.
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Re: December 2020 Forecasts and Discussions

Post by Monty »

Split the difference between the gfs and gem and it could snow early next week.
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Re: December 2020 Forecasts and Discussions

Post by Antares »

Personally I think the models spoil things a bit.

Like last January, if I had not looked at all those amazing model runs, it wouldn't have seemed like such a dud. :lol:
It always snows in December in the Kootenays :clap:
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Re: December 2020 Forecasts and Discussions

Post by Monty »

Antares wrote: Wed Dec 16, 2020 10:00 am Personally I think the models spoil things a bit.

Like last January, if I had not looked at all those amazing model runs, it wouldn't have seemed like such a dud. :lol:
If last January felt like a dud then yea you gotta move :arrow:
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Re: December 2020 Forecasts and Discussions

Post by wetcoast91 »

Monty wrote: Wed Dec 16, 2020 10:09 am If last January felt like a dud then yea you gotta move :arrow:
To be fair, some runs were showing an extended period of cold rivaling Dec 2008 with a Jan 1990 setup of a baroclinic snowstorm. Some runs even had 50-60" of snow over a full week. This turned to be 20" with some areas seeing 30." It overperformed in the close range days but extended runs had persistent cold and snow which morphed into a warm zonal/AR event.

Now Jan 2011 (?). That was a clear bust within 72 HR. Went from a PDX snowstorm, to a SEA snowstorm, to a YVR snowstorm to a overrunning event followed by +12 sunshine the next day.
Last edited by wetcoast91 on Wed Dec 16, 2020 10:27 am, edited 1 time in total.
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Re: December 2020 Forecasts and Discussions

Post by Bonovox »

Not a bad GEFS run.
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Spring/Summer :sick: Fall/Winter :thumbup:

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Re: December 2020 Forecasts and Discussions

Post by Antares »

January 2020 basically went like this:

*******\_____/*********************

* = Rain/zonal flow
_ = Snow/cold temps

It's to be expected here though. That kind of progression is all too common, so it wasn't too surprising. It was just incredibly depressing to go back to the zonal flow after dealing with that all of December and part of early January. :lol:
It always snows in December in the Kootenays :clap:
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Re: December 2020 Forecasts and Discussions

Post by stuffradio »

12Z GFS for YXX, 200mm through 386 hours.
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Re: December 2020 Forecasts and Discussions

Post by Abby_wx »

January was a bit of a dud here... I barely hit 12" for the month. There were a couple of days that were impressively chilly during the day. There were no impressive overnight lows, though.
:dragon:

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Low min: -16.6C (Jan 12th)
Low max: -9.9C (Jan 12th)
Snowfall: 8.0 cm
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Re: December 2020 Forecasts and Discussions

Post by wetcoast91 »

12Z ECMWF shoves that trough too far east. REX block looks healthier along the West Coast and keeps us dry from Mon through Xmas Eve. Mild rain finally moves in for Xmas.

Image


Looks like some +8C drizzle for xmas!
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Re: December 2020 Forecasts and Discussions

Post by Monty »

wetcoast91 wrote: Wed Dec 16, 2020 10:25 am To be fair, some runs were showing an extended period of cold rivaling Dec 2008 with a Jan 1990 setup of a baroclinic snowstorm. Some runs even had 50-60" of snow over a full week. This turned to be 20" with some areas seeing 30." It overperformed in the close range days but extended runs had persistent cold and snow which morphed into a warm zonal/AR event.

Now Jan 2011 (?). That was a clear bust within 72 HR. Went from a PDX snowstorm, to a SEA snowstorm, to a YVR snowstorm to a overrunning event followed by +12 sunshine the next day.
I guess model solutions showing 150cm of snow with lows of -20C should be looked at with just a pound of skepticism. It was probably some of the best powder snow a lot of people have seen in a decade or more. Anyway, every little microclimate has their own experiences, I think January had the coldest deep powder I’ve seen here since 1996.
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