Jump to content
  • Member Statistics

    17,608
    Total Members
    7,904
    Most Online
    NH8550
    Newest Member
    NH8550
    Joined

Winter 2014/15 Med/Long Range Discussion Part 3


Chicago Storm

Recommended Posts

  • Replies 1k
  • Created
  • Last Reply

All aboard!

 

yQIp02h.png

Ha, I love it. A couple of those clippers stay further north, but those will trend south in a hurry with any east coast development to buckle the flow.

We enjoyed our day off, now it's time to get back to business. Clipper one gets underway in 18 hours or so. And the GEM trended slightly toward the deeper Euro tonight for Wed night.

Link to comment
Share on other sites

Ha, I love it. A couple of those clippers stay further north, but those will trend south in a hurry with any east coast development to buckle the flow.

We enjoyed our day off, now it's time to get back to business. Clipper one gets underway in 18 hours or so. And the GEM trended slightly toward the deeper Euro tonight for Wed night.

6Z GFS run was overall pretty nice too!!

Link to comment
Share on other sites

12z Euro north again with the 2/7-8 system. Might be a nice consolation storm for some of the below normal areas up north (DLH, MSP, GRB, northern lower MI, etc). Good hit for MKE, GRR, and DTW as well.

 

 

Curious to know what the thermals are like on that run.  With the deep snowpack and a high to the north, it seems like perhaps a candidate for ice just south of the snow line.

Link to comment
Share on other sites

Loving this weekend potential, starting to look like a pretty good hit here locally.

Oddly similar to 2/8/13 in terms of areas impacted/the hybrid setup and happens to fall on its second anniversary. There are obvious differences in terms of the amount of S stream interaction, but its an interesting setup.

Link to comment
Share on other sites

The latest weeklies have a continuing +PNA/-EPO look right through early March. NAO and AO are neutral for the most part, but no real sign of any Atlantic blocking. A pattern like this is boring, lol. Just a string of clippers for the most part. With a +PNA/-EPO combo, you have the mean trough in the East with a ridge out West. This pattern screams clippers as the Polar jet stream is enhanced with the southern stream locked out in the south. Another word for this would be a "rex block". 

 

The strong Pacific jet stream will mean continuous storm development in the Pacific, so the El Nino is having some forcing globally, but not your typical El Nino as it hasn't been consistent from an Atmospheric standpoint. Would be nice if we can get a -EPO/neutral PNA pattern with the mean trough in the Plains/Midwest and mean ridge around Alaska. This is an ideal pattern for storm development especially if we have a weak SE Ridge creating a nice gradient boundary. 

 

The Eurasian snow-cover theory didn't hold well for a 2nd season in a row. Again its just a theory but with a decently high probability rate, its surprising how off it was. Just another reason for Mother nature to gloat, haha. 

Link to comment
Share on other sites

The latest weeklies have a continuing +PNA/-EPO look right through early March. NAO and AO are neutral for the most part, but no real sign of any Atlantic blocking. A pattern like this is boring, lol. Just a string of clippers for the most part. With a +PNA/-EPO combo, you have the mean trough in the East with a ridge out West. This pattern screams clippers as the Polar jet stream is enhanced with the southern stream locked out in the south. Another word for this would be a "rex block". 

 

The strong Pacific jet stream will mean continuous storm development in the Pacific, so the El Nino is having some forcing globally, but not your typical El Nino as it hasn't been consistent from an Atmospheric standpoint. Would be nice if we can get a -EPO/neutral PNA pattern with the mean trough in the Plains/Midwest and mean ridge around Alaska. This is an ideal pattern for storm development especially if we have a weak SE Ridge creating a nice gradient boundary. 

 

The Eurasian snow-cover theory didn't hold well for a 2nd season in a row. Again its just a theory but with a decently high probability rate, its surprising how off it was. Just another reason for Mother nature to gloat, haha. 

 

It seems that between storms we are super cold, but as the storms approach, nothing keeps them from moving too far north and screwing us.

Link to comment
Share on other sites

It seems that between storms we are super cold, but as the storms approach, nothing keeps them from moving too far north and screwing us.

 

Yeah. The weeklies keep the PV on our side of the globe and this allows for continuous cold week in and out as the +PNA doesn't want to break lose. Hard to cool down the PDO with a +PNA. A -PDO is good for our region because it creates a more poleward Aleutian ridge (-EPO) and aides in the protraction of La Nina's.  If i could post the weeklies here i would, but it basically shows a repeat of last Winter right through Week 4, lol. With the +PNA, the southern stream of energy is locked out from going anywhere. The PV to the north will likely shred some clippers out of there energy and all were left with is maybe 1-4" thanks to the high ratios. It's a nickel and dime season, haha.

 

Unless the +PNA breaks down some, the STJ will have little effect on us. New England is in an ideal spot. The warm waters of the Atlantic will refuel the clippers as they get out of the area and this will give them countless opportunities at seeing 6"+ in this pattern. 

Link to comment
Share on other sites

The latest weeklies have a continuing +PNA/-EPO look right through early March. NAO and AO are neutral for the most part, but no real sign of any Atlantic blocking. A pattern like this is boring, lol. Just a string of clippers for the most part. With a +PNA/-EPO combo, you have the mean trough in the East with a ridge out West. This pattern screams clippers as the Polar jet stream is enhanced with the southern stream locked out in the south. Another word for this would be a "rex block". 

 

The strong Pacific jet stream will mean continuous storm development in the Pacific, so the El Nino is having some forcing globally, but not your typical El Nino as it hasn't been consistent from an Atmospheric standpoint. Would be nice if we can get a -EPO/neutral PNA pattern with the mean trough in the Plains/Midwest and mean ridge around Alaska. This is an ideal pattern for storm development especially if we have a weak SE Ridge creating a nice gradient boundary. 

 

The Eurasian snow-cover theory didn't hold well for a 2nd season in a row. Again its just a theory but with a decently high probability rate, its surprising how off it was. Just another reason for Mother nature to gloat, haha. 

What is the Eurasia snowcover theory?

Link to comment
Share on other sites

From the best Met in Buffalo
 

After a nearly forgotten very mild and much less snowy than average December, the weather worm turned around January 5th. That’s when we began our downward spiral for most of last month and into this month. A rather persistent western ridge (with minor variations) have keep the west and central US with above average temperatures. An absence of blocking over the North Atlantic has allowed the eastern trough to set up far enough east to restrict most of the really cold weather to the eastern Great Lakes and the NE, into eastern Canada as well.

 

This high amplitude pattern is going to relax somewhat for a few days, allowing for much less harsh temperatures over the weekend. The price to be paid will be several waves of low pressure moving along a boundary between arctic air to the north and moist Pacific air to the south. Temperatures will be somewhat below average for the first half of next week, but by later in the week, a reamplification of the western ridge/eastern trough will occur. This has been showing up in model ensemble means for quite a while.

 

With the considerable help of long range forecaster Dr. Judah Cohen, I’m stuck with the unpleasant task of telling people we are nowhere near out of this frigid mess. There is even some chance matters may grow worse. Cohen writes of evidence in the GEFS ensemble and less robust evidence in the ECMWF that the blocking in the North Atlantic which has been absent most of the winter is going to begin to develop. The polar vortex which has been settled lately over the far north of Eurasia is going to drift back toward the north pole. What this favors is a strengthening of the western ridge, which teleconnects with a strengthening of the eastern trough, and more frigid air pouring not only into the NE but retrograding into the central states as well. These teleconnections favor more cross-polar flow. In addition, at about the same time the N Atlantic ridging develops, the MJO will be entering what’s called phase 7 & 8, which correlates with below average temperatures in our part of the country. It’s far from certain that the N Atlantic blocking will become strong, but if it does the NAO would finally go strongly negative–it’s been a nonfactor this winter–and the AO (currently weakly & briefly negative before it goes positive again next week) would go negative as well. The fact that the AO has been positive the majority of the time in the last 4-5 weeks speaks to how poor a predictor in this winter as to cold and snow in the east/NE.

 

This pattern, with minor variations, is expected to persist into early March in Cohen’s eyes, as I’d speculated the other night on the previous thread. This is a draining, disruptive pattern leading to economic dislocation, high energy costs, and damage to our infrastructure. If we’re correct, this will be one of the longest cold periods in a number of years.

Link to comment
Share on other sites

What is the Eurasia snowcover theory?

 

According to Mr. Cohen, October snow cover in Eurasia and Siberia can play a role in predicting the AO for the following Winter. His theory states that a large increase in October snow cover will aide in the development of a -AO/NAO for DJF. This is what happened in 2009 when we saw extreme blocking across the Arctic and most of the sub-forum was shunned away from seeing any massive storms like what the mid-Atlantic saw.  

 

On a more scientific description, the increased snow cover increases LP's across Siberia and this enhances Poleward Heat Fluxes into the Atmosphere. Continuous Wave developments overtime will tear away the PV in the stratosphere and enough warming may initiate a SSW (Sudden stratospheric warming) event. It doesn't always mean were going to get cold and snowy conditions in the region. In 2011-12 the SSW didn't help us at all but brought a freezer out in Europe come February, lol. I'm not an expert in some of this, i just know the basics for weather in general but thats what I learned over-time. 

 

You can read this if you want. 

 

http://www.nws.noaa.gov/ost/climate/STIP/FY11CTBSeminars/jcohen_062211.pdf

Link to comment
Share on other sites

Thanks for posting this, BuffaloWeather. I've been watching Don Paul for 20 years now (WIVB is available on cable systems in the Golden Horseshoe/GTA). He's the best met in the Buffalo area.

The persistence in the current pattern is incredible. Despite the mild December, we are on pace to have another below normal winter, temperature-wise.

Link to comment
Share on other sites

According to Mr. Cohen, October snow cover in Eurasia and Siberia can play a role in predicting the AO for the following Winter. His theory states that a large increase in October snow cover will aide in the development of a -AO/NAO for DJF. This is what happened in 2009 when we saw extreme blocking across the Arctic and most of the sub-forum was shunned away from seeing any massive storms like what the mid-Atlantic saw.  

 

On a more scientific description, the increased snow cover increases LP's across Siberia and this enhances Poleward Heat Fluxes into the Atmosphere. Continuous Wave developments overtime will tear away the PV in the stratosphere and enough warming may initiate a SSW (Sudden stratospheric warming) event. It doesn't always mean were going to get cold and snowy conditions in the region. In 2011-12 the SSW didn't help us at all but brought a freezer out in Europe come February, lol. I'm not an expert in some of this, i just know the basics for weather in general but thats what I learned over-time. 

 

You can read this if you want. 

 

http://www.nws.noaa.gov/ost/climate/STIP/FY11CTBSeminars/jcohen_062211.pdf

thanks

Link to comment
Share on other sites

The cold continues. it doesnt really matter what route we go sunday...freezing rain, drizzle, no precip at all...sunday itself is just pointless. Will we lose all the snow? Absolutely not. Not even close. But it will muck up some from a one day thaw (mos has 42F) and we go right back into the deep freezer for the foreseeable future. Generally when this happens the snow still looks nice in the yard but gets dirty by the road. So hoping the NW flow offers refreshers. Nothing uncommon about a thaw, I guess we have just been so lucky in recent years im like the spoiled brat who gets more than he should but wants more more more.

Link to comment
Share on other sites

The cold continues. it doesnt really matter what route we go sunday...freezing rain, drizzle, no precip at all...sunday itself is just pointless. Will we lose all the snow? Absolutely not. Not even close. But it will muck up some from a one day thaw (mos has 42F) and we go right back into the deep freezer for the foreseeable future. Generally when this happens the snow still looks nice in the yard but gets dirty by the road. So hoping the NW flow offers refreshers. Nothing uncommon about a thaw, I guess we have just been so lucky in recent years im like the spoiled brat who gets more than he should but wants more more more.

There will at least be some penny refreshers.  Likely a few nickle and dimers too!

Link to comment
Share on other sites

Global AAM propagating up and that usually signifies that the Atmosphere is starting to resemble a typical Nino. The weeklies showed this nicely with a strong +PNA and clipper pattern. Some downwelling in the sub-surface will cool down the Eastern regions in the coming weeks, while the Western regions warm-up. West based Nino? By Week 3/4 the weeklies started showing a developing -PNA/SE ridge pattern with a continuing -EPO. If the PDO begins cooling down in Spring, the chances of La Nina next season could increase. 

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...