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Medium/Long Range Discussion Part 2

IWXwx

By IWXwx,
in Lakes/Ohio Valley

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snowstormcanuck

snowstormcanuck

Posted
Posted

Think the problem overall is that our -NAO looks to be too west based. This leep heights persistently low across Hudson Bay/Quebec. Everything coming in from the Pacific is going to quashed in a pattern like that with extreme confluence across SE Canada/New England.

The one good piece of news is that when I look at EURO through 240, there are an abundance of s/ws crashing into the west coast. All you need is a little kink in the polar jet, or for the vortex to retrograde slightly, and it's possible one of these things could blow up. But it's the epitome of thread the needle.

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buckeye

buckeye

Posted
Posted

Think the problem overall is that our -NAO looks to be too west based. This leep heights persistently low across Hudson Bay/Quebec. Everything coming in from the Pacific is going to quashed in a pattern like that with extreme confluence across SE Canada/New England.

The one good piece of news is that when I look at EURO through 240, there are an abundance of s/ws crashing into the west coast. All you need is a little kink in the polar jet, or for the vortex to retrograde slightly, and it's possible one of these things could blow up. But it's the epitome of thread the needle.

For us a bit further south, we need that vortex too relax when one of those sw monsters come out and you end up with a PDII - type scenario. Major overrunning in the midwest and OV. Been awhile since we had a juicy west to east overrunning event.

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snowstormcanuck

snowstormcanuck

Posted
Posted

Brett Andersons long range

590x450_12281304_dec28a.png

590x450_12281305_dec28b.png

590x450_12281306_dec28c.png

I'm assuming these are Anderson's interpretation of the EURO weeklies. Looks like we'll have to wait for mid January to have some action resume.

Disappointing thing about this cold pattern coming up for the next week or so is that the flow looks dry/anti-cyclonic. Even though 850s are going to flirt with -20, doesn't look like a lot of potential for any huge LES outbreaks.

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Ottawa Blizzard

Ottawa Blizzard

Posted
Posted

I'm assuming these are Anderson's interpretation of the EURO weeklies. Looks like we'll have to wait for mid January to have some action resume.

Disappointing thing about this cold pattern coming up for the next week or so is that the flow looks dry/anti-cyclonic. Even though 850s are going to flirt with -20, doesn't look like a lot of potential for any huge LES outbreaks.

I always find it difficult to interpret 850 temperatures. The GFS shows the -18C 850 isotherm going south of us, yet EC is calling for highs in the low to mid twenties. Hardly severe cold.

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snowstormcanuck

snowstormcanuck

Posted
Posted

I always find it difficult to interpret 850 temperatures. The GFS shows the -18C 850 isotherm going south of us, yet EC is calling for highs in the low to mid twenties. Hardly severe cold.

You know the drill. EC is usually too warm in the extended because the GGEM is a warm biased model. However, even the GGEM is showing it getting pretty damn cold by next Thursday. I'd expect those numbers to come down some over the next couple of days. GFS MOS has temps in the mid teens next Thursday.

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QVectorman

QVectorman

Posted
Posted

Since things are slow in here I figured I would add my posts from yesterday in the NE forum here to give some thing for discussion or give some hope

With the MJO going into phase 1 and the 5-7 day lag for MJO induced waves to traverse the eastern US it would set us up for a wave to arrive in the east between Dec. 18-20 which is progged on the 180hr GFS and Euro moving across the upper Midwest or Great Lakes. The same wave also ushers in relatively "colder" air and plays nicely into the idea I spoke of the other day in my post about the pocket of relatively "colder" air arriving during the Dec. 21-23 time frame based off of GWO analogs for the eastern US.Using that same concept for the GWO I expect another batch of colder air Dec. 27-30. And Following the spike in the 10 and 30 mb temps that peaked back on Dec. 6 seems we should see a good shot of colder air Dec 30-Jan 3.

With the newest GWO numbers today the latest analogs indicate a 15-20F warm up in sfc temps Jan 3-Jan 6 compared to prior days highs across Midwest or NE (the Dec. 31-Jan 3 cold episode) and analogs suggest a stair stepped 15-20F temperature fall behind the warm up 1-2 days after that, meaning another spell of colder air Jan 5-8.

I extended my outlook through Jan 8 on Dec. 14. I still feel comfortable with those dates and with the newest GWO analogs and latest 10 and 30 mb temp forecast it appears the time frame between Jan 8-10 will see a warm up over the east with a short wave moving through the east Jan 10-11 with cooler air dropping in behind it for Jan 10-13 across the MW/GLKS and then pockets of cooler air arriving Jan 15-19 time frame for the east followed by a second reinforcement of cooler air Jan 20-24. My GWO analogs only take me out to Jan 9 so there may be another short wave or two to add to the 2 already expected for the Jan 9-24 time frame. I will update as the newest GWO numbers come out over the next week and half.

I was going to wait until we were upon the first wave of cold air in my date windows but things are slow again in here and the models look like there are in pretty good agreement so I think it's safe to post a analysis and extend the forecast.

First Dec. 27-30 window as mentioned back on Dec. 13...we have the Euro 39h 850's for Dec. 30 with the cold pool of -10 to -12C air covering most of the MW/NE.

post-3697-0-53538300-1356739878_thumb.jp

After a brief stint of southerly flow on the back side of a hp over Florida 850's warm to 0 to -2C over IN, OH and parts of MI for Dec. 31

Second window Dec. 30-Jan 3 as mentioned back on Dec. 13...signs still pointing to much colder air arriving over the Eastern US...the Euro at 156h 850's for Jan 4 0z---Jan 3 7pm EST with -20 to -22C over WI and N. MI

post-3697-0-33416400-1356740336_thumb.jp

It appears the Jan 20-24 cold shot should be comparable in magnitude of the upcoming Jan 2-3 airmass. Also latest GWO numbers are currently trending towards an agreement of the Jan 20-24 date. I will have concrete confirmation or rejection of that assumption by Tues.

Extending the outlook Jan 24-26 show up as next pocket of cooler air...although I will say signals are mixed on this window date so I'm not too confident on this time frame producing a cooler airmass for the MW/NE.

Although Jan 26-30 looks very impressive and should out do the Jan 2-3 850mb cold air wrt temps. The newest ECMWF strat. temp forecast shows a ~+48C warming at 10mb from Dec. 29 through Jan. 2 and a ~+42C warming from Jan1 to Jan 2. There is also a wind reversal forecasted to take place Jan 2 at 1mb and 10mb at 60N. This should qualify as a MAJOR SSW since only a +25C temp change is required over a week period for a minor SSW and I believe the wind reversal is extensive enough to qualify also. If not it is still a minor SSW. The EP vector is also forecasted poleward at least at 90N which is a good signal that the SSW will in fact allow arctic air to spill southward. This event should produce the Jan 26-30 window cold pocket...Although I don't have much experiencing timing out SSW events so this may not be the exact window, it may have to be adjusted forward or backwards by a few days.

post-3697-0-66775700-1356743976_thumb.jp

I will also say that it appears a lot of these dates are back to back and should mention that these forecasted chunks of cooler/colder air are cooler/colder relative to the air in place that they displace. So I don't claim to know the temperature range of the 850mb temps arriving...The concept can only forecast that it will be "colder" than the one that will be in place at the time of it's arrival and are associated with shortwaves so there will be brief time frames of southerly winds ahead of the short waves that will produce WAA ahead of waves and as a result might produce brief minor spikes in 850 temps and sfc temps in transition from time frame to time frame. So for example over a period of days (windows) it could just go from -2C...cool to -5C (window/event 1) then warm to 0C and cool to -4 (window/event 2) where event 2 ends up "cooling" but ends up actually with warmer temps than just a few days prior but cooler compared to just 1 or 2 days prior.This also doesn't elude to AA temps or BA temps just "relative" so even with all the time frames for shortwaves thus...colder airmasses; it doesn't rule out that the resulting cooler temps still produce above average temperatures for daytime highs.When the signals are stronger an estimation of the temp of the air is possible such as the Jan. 2-3 and Jan 20-24 and Jan 26-30 episode. The other time frames are just hiccups in the stat. signal and coincide to minor dips in sfc temperatures relative to previous days' highs but I figure they are worth mentioning.

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Ottawa Blizzard

Ottawa Blizzard

Posted
Posted

You know the drill. EC is usually too warm in the extended because the GGEM is a warm biased model. However, even the GGEM is showing it getting pretty damn cold by next Thursday. I'd expect those numbers to come down some over the next couple of days. GFS MOS has temps in the mid teens next Thursday.

Yeah, the GGEM is warm biased...big time.

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snowstormcanuck

snowstormcanuck

Posted
Posted

I extended my outlook through Jan 8 on Dec. 14. I still feel comfortable with those dates and with the newest GWO analogs and latest 10 and 30 mb temp forecast it appears the time frame between Jan 8-10 will see a warm up over the east with a short wave moving through the east Jan 10-11 with cooler air dropping in behind it for Jan 10-13 across the MW/GLKS and then pockets of cooler air arriving Jan 15-19 time frame for the east followed by a second reinforcement of cooler air Jan 20-24. My GWO analogs only take me out to Jan 9 so there may be another short wave or two to add to the 2 already expected for the Jan 9-24 time frame. I will update as the newest GWO numbers come out over the next week and half.

I was going to wait until we were upon the first wave of cold air in my date windows but things are slow again in here and the models look like there are in pretty good agreement so I think it's safe to post a analysis and extend the forecast.

First Dec. 27-30 window as mentioned back on Dec. 13...we have the Euro 39h 850's for Dec. 30 with the cold pool of -10 to -12C air covering most of the MW/NE.

post-3697-0-53538300-1356739878_thumb.jp

After a brief stint of southerly flow on the back side of a hp over Florida 850's warm to 0 to -2C over IN, OH and parts of MI for Dec. 31

Second window Dec. 30-Jan 3 as mentioned back on Dec. 13...signs still pointing to much colder air arriving over the Eastern US...the Euro at 156h 850's for Jan 4 0z---Jan 3 7pm EST with -20 to -22C over WI and N. MI

post-3697-0-33416400-1356740336_thumb.jp

It appears the Jan 20-24 cold shot should be comparable in magnitude of the upcoming Jan 2-3 airmass. Also latest GWO numbers are currently trending towards an agreement of the Jan 20-24 date. I will have concrete confirmation or rejection of that assumption by Tues.

Extending the outlook Jan 24-26 show up as next pocket of cooler air...although I will say signals are mixed on this window date so I'm not too confident on this time frame producing a cooler airmass for the MW/NE.

Although Jan 26-30 looks very impressive and should out do the Jan 2-3 850mb cold air wrt temps. The newest ECMWF strat. temp forecast shows a ~+48C warming at 10mb from Dec. 29 through Jan. 2 and a ~+42C warming from Jan1 to Jan 2. There is also a wind reversal forecasted to take place Jan 2 at 1mb and 10mb at 60N. This should qualify as a MAJOR SSW since only a +25C temp change is required over a week period for a minor SSW and I believe the wind reversal is extensive enough to qualify also. If not it is still a minor SSW. The EP vector is also forecasted poleward at least at 90N which is a good signal that the SSW will in fact allow arctic air to spill southward. This event should produce the Jan 26-30 window cold pocket...Although I don't have much experiencing timing out SSW events so this may not be the exact window, it may have to be adjusted forward or backwards by a few days.

post-3697-0-66775700-1356743976_thumb.jp

I will also say that it appears a lot of these dates are back to back and should mention that these forecasted chunks of cooler/colder air are cooler/colder relative to the air in place that they displace. So I don't claim to know the temperature range of the 850mb temps arriving...The concept can only forecast that it will be "colder" than the one that will be in place at the time of it's arrival and are associated with shortwaves so there will be brief time frames of southerly winds ahead of the short waves that will produce WAA ahead of waves and as a result might produce brief minor spikes in 850 temps and sfc temps in transition from time frame to time frame. So for example over a period of days (windows) it could just go from -2C...cool to -5C (window/event 1) then warm to 0C and cool to -4 (window/event 2) where event 2 ends up "cooling" but ends up actually with warmer temps than just a few days prior but cooler compared to just 1 or 2 days prior.This also doesn't elude to AA temps or BA temps just "relative" so even with all the time frames for shortwaves thus...colder airmasses; it doesn't rule out that the resulting cooler temps still produce above average temperatures for daytime highs.When the signals are stronger an estimation of the temp of the air is possible such as the Jan. 2-3 and Jan 20-24 and Jan 26-30 episode. The other time frames are just hiccups in the stat. signal and coincide to minor dips in sfc temperatures relative to previous days' highs but I figure they are worth mentioning.

Thanks for this analysis QVectorman. I'll admit most discussion regarding SSW goes right over my head. Regardless, I'm looking forward to the potential cold snap. :)

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Chicago WX

Chicago WX

Posted
Posted

Top 20 worst starts to a snow season for Milwaukee, through December. 3.8" at MKE through yesterday for 2012. I'm not sure if to believe the additional 3.1" for today in the evening climate report (below)...but if it's correct, well, this will all be for naught. The total in ( ) is the total amount of snowfall that fell after December for each season.

CLIMATE REPORT

NATIONAL WEATHER SERVICE IN MILWAUKEE

644 PM CST SAT DEC 29 2012

...THE MILWAUKEE WI CLIMATE SUMMARY FOR DECEMBER 29 2012...

VALID TODAY AS OF 0600 PM LOCAL TIME.

SNOWFALL (IN)

TODAY 3.1

MONTH TO DATE 6.9

SINCE DEC 1 6.9

SINCE JUL 1 6.9

SNOW DEPTH 2

For reference, 1981-10 total normal snowfall for Jan-May at MKE is 33.6"

1939-40: 0.4" (41.9")

1888-89: 0.6" (28.3")

1913-14: 1.2" (23.7")

2011-12: 1.2" (28.4")

1906-07: 1.3" (26.8")

1943-44: 1.6" (19.4")

1912-13: 1.9" (23.2")

1999-00: 2.3" (35.3")

1928-29: 2.4" (40.3")

1967-68: 2.4" (9.7")

2001-02: 2.6" (33.9")

1979-80: 2.7" (44.3")

1889-90: 2.8" (37.0")

1927-28: 2.8" (24.7")

1948-49: 2.8" (27.2")

1953-54: 2.9" (14.9")

1982-83: 3.4" (34.6")

1998-99: 3.7" (57.0")

2003-04: 3.8" (35.4")

2004-05: 3.9" (44.3")

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