Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
what I would like to know is what makes one winter shove much more extreme cold further south, vs another winter that was way more colder but didn't shove as much further south. These are the nuances I'm interested in.
Quote:
Originally Posted by chicagogeorge
Good question. Could it have something to do with that cold traveling over snow pack as it goes south of Chicago? No snow, less cold.
I love talking about stuff like this. The science aspect of the atmosphere and surface conditions. Only select few meteos actually get into it, Steve D talks about it a lot.
Leaving out the "rain" as the cool result, For instance an active sub tropical Jet in winter but a weak Polar Jet that stays in Canada will give northern U.S warmth yet the south colder then normal because of the clouds and rain associated with the Sub jet...
But as far as the actual Extreme cold push down from Canada.. it could be as simple as the troughs not digging south enough one winter vs another winter or as complicated as what's physically happening downstream in the West and up stream in the North in Canada and East of us in the Atlantic.
If there is a thick cold snowpack in Canada and a frozen Hudson Bay or Great Lakes, wind has less restriction. So if there is a Ridge that pumps up in the West, a trough is more likely to dig further south in the East and without restriction on wind, the colder air pushes south more. So one winter will shove the cold further south then another. Add High Pressure over Greenland (blocking) and the cold stays longer hence gives more below normal results.
Above normal snow growth in Siberia and Canada leads to a negative Arctic Oscillation (AO) and North Atlantic Oscillation (NAO) in the winter and also leads to stronger Polar and Arctic air masses to invade the eastern United States.
So bottom line without a Polar Jet stream digging we don't get the big cold. Without the Sub Tropical Jet stream we don't get the big snows. Where and how far the Polar Jet stream digs south all depends on many factors some listed above.. If you ever get a chance to play a loop of the entire Northern Hemisphere it's so fascinating to see how the atmosphere and 500mb level always flows, loops, and moves and gives you a sense of timing and depth of these Cold troughs.
Take whats happening this week for instance... Yes just September but same rules apply.
Check out the trough that's digging into the South!
First, you got a zonal flow across Western Canada.. that is injecting warmer air into the trough so while the trough is digging further south, the air is moderating and not cold.
Of course its still September but you can see why sometimes the push of air down south is not as extreme one week/month vs another.
But it's still impressive for this time of year.. Single digits at 850mb down to Kentucky?!!
nice look at the cold air building up over the Pole!
Also note how the Hudson Bay plays a role! If that is frozen over and there is frigid air, that will flow right down and into the U.S
I have had my run ins with this forecasting company. What a joke. He has a facebook page, and last winter I went after them for their blown February forecast. They claim to be soooo accurate, and he cherry picks temp data to make it look like they got last winter forecast right. I told him JB (he knows JB) called it exactly right (backended winter) and claimed JB has a total bias. We agree with that, but his forecasts are still pretty darn good last winter.
Anyway, the guy banned me from his Fbook page cause I called him out for his blown forecast. Guy has a super ego.
What he is excellent at is lumping all four winter months together to minimize how blown his Feb, March and April forecast was. He called for a very mild Spring also.
Well, here is their winter forecast for this year. I've yet to see one other forecaster call for such an out on the limb forecast. Check it out. It is heavily based on a super super El Nino. I can't wait to see how he weasels out of this forecast come March.
Here is his blog for last winter, and his accompanying after action report. Again, he played with the data to make it seem like they called last winter. They didn't.
Their early winter forecast last year: couldn't be more wrong.
Anyway, the guy banned me from his Fbook page cause I called him out for his blown forecast. Guy has a super ego.
I don't know how he stays in business tbh.
Haha. You should follow WXRisk. He loves to insult when you dont agree with him. He'll call you a drunk, stupid, idiot, ect. He actually looks like a pedifile. Lmao.
They stay in business because they create a stir up. If you dont have backup to support your success it makes sense to say and do things to draw attention to your business. Although even if successful or having a higher percentage of being right Id still stir up some extra clicks.
Haha. You should follow WXRisk. He loves to insult when you dont agree with him. He'll call you a drunk, stupid, idiot, ect. He actually looks like a pedifile. Lmao.
They stay in business because they create a stir up. If you dont have backup to support your success it makes sense to say and do things to draw attention to your business. Although even if successful or having a higher percentage of being right Id still stir up some extra clicks.
That guy is a trip. Great site. He tells it like it is. I like how he dissects that guys winter forecast. Very true what he is saying. I will follow him. I like people that back up their forecasts with logical thought out reasoning, hopefully without hype. I love it when he calls people as..... for defending TWC. I loved that.
Please register to post and access all features of our very popular forum. It is free and quick. Over $68,000 in prizes has already been given out to active posters on our forum. Additional giveaways are planned.
Detailed information about all U.S. cities, counties, and zip codes on our site: City-data.com.
Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
- Blog - weathertrends360
