STORM2K

The models are jumping all over the place beyond this weekend. What we know is that very cold air is going to build in western Canada early next week and with blocking it will have to move somewhere.

TeamPlayersBlue wrote:I find it hard to believe the temps of the Euro with that type of setup.

The MSLP levels on the GFS seem a bit more realistic.

The lesser cold runs develop the cyclone up north and it wraps the coldest air around it, more of glancing blow. If the cyclone develops further south then trajectory is colder. Of course all this is dependent on how well the model sees the movement of the cold air. We know it is a very cold air mass.

18Z GFS is about 200 miles further south and a bit slower with the low next week compared to the 12Z run. It has snow down to the Red River on Thursday.

Long range keeps reloading cold air in our source region and putting it on the shot block down to our smiling faces

Midday temperatures next Thursday near freezing at DFW on the gfs... even before the Arctic air the warmest high is 60.

Fairbanks, Alaska today had a daytime high (as of 3.53PM local time there) of -22F. Normal high is a balmy 7F, a departure of 29F below normal. Some areas in Alaska didn't get out of the -30s! Yikes that's cold.

Ntxw wrote:Fairbanks, Alaska today had a daytime high (as of 3.53PM local time there) of -22F. Normal high is a balmy 7F, a departure of 29F below normal. Some areas in Alaska didn't get out of the -30s! Yikes that's cold.

Come to Papa!

I'll be hiking and skiing in Western Montana the last week of December so I'm hoping for some extreme weather to test me.

Ntxw wrote:Fairbanks, Alaska today had a daytime high (as of 3.53PM local time there) of -22F. Normal high is a balmy 7F, a departure of 29F below normal. Some areas in Alaska didn't get out of the -30s! Yikes that's cold.

And before the Aleutian ridge blocked the Pacific Maritime air, in mid November they were often in the 20s and 30s which was 15-20 degrees above normal. Amazing what happens when you block the ocean air and switch the winds towards Asia. No doubt the pattern above the North Pacific controls how cold North America gets.

Ntxw， how strong is the hp on the gfs，cmc，and euro? Also， in reality what do we need to see happen for us to see a better chance at a winter event here? Trough a little further east?

How much rain are going to get this weekend? How cold is going to get next week?

Golf7070 wrote:Ntxw， how strong is the hp on the gfs，cmc，and euro? Also， in reality what do we need to see happen for us to see a better chance at a winter event here? Trough a little further east?

I think anywhere from 1045-1055 is a reasonable guess. The stronger the high the further south the deep cold will get pushed. Would like to see ridging get stronger perhaps 564dm at 500mb or greater into NW Canada but details like that are not reasonably caught until within 100 hours.

We've had snowstorms and ice storms with 1035-1040 if positioned right and the source region is cold. But for really big cold you'd want to see 1050+ in Montana.

starsfan65 wrote:How much rain are going to get this weekend? How cold is going to get next week?

Half an inch to an inch. Southeast Texas a little more perhaps 1-2"+ and greater locally. Lows in the 20s/ highs in the 30s and 40s after frontal passage of the arctic front probably.

Ntxw，is there any chance the hp is 1050+ or does the pattern not support it in the pacific? I mean if thats our only realistic chance to perhaps see a winter storm or ice storm.or something? Do you think the alutian high can come back once it breaks down or even get an alaskan ridge? Just curious

Golf7070 wrote:Ntxw，is there any chance the hp is 1050+ or does the pattern not support it in the pacific? I mean if thats our only realistic chance to perhaps see a winter storm or ice storm.or something? Do you think the alutian high can come back once it breaks down or even get an alaskan ridge? Just curious

Strength of the surface high often is linked to how strong the blocking is over Alaska/NW Canada from the Pacific. The relation is very simple, you block the ocean air and the air over land can get cold. Mix in warmer Ocean air and it warms up quickly. The Aleutian high is a dominant feature of La Nina just as the Aleutian low is the dominant feature of El Nino. We are in weak Nina/cold neutral so the Aleutian high tends to kick in during the winter months. It's a semi-permanent feature now. If and when the high nudges to Alaska then cold air moves south from Canada.

It could go 1050+, but if the air over western Canada is very cold, you won't need that strong a HP to being an arctic front. Just with the stronger HP the more likely you are to drive it south with more veracity.

1048 MB minimum crossing the border i think. Anything above that really grabs the attention and brings cold air down.

Just a little more south

Brent wrote:Just a little more south

http://www.tropicaltidbits.com/analysis ... cus_35.png

this GFS run actually focuses a lot of the vorticity more to the south than the previous few runs. Not to mention it's been all over the place in general.

Past 6 runs for the same day

It is slowly trending further south, right?

The cold air is much more progressive this run also... warms up fairly quickly, but this is fantasy land.