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Medium/Long Range Discussion Part 2


IWXwx

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alrighty trying to make sense of this scenario for next weekend , Flying into MSP for 6 days to hang out with a good friend on the 12th who lives in Waconia MN, been reading some discussions and trying to understand . You all live up this way and know the weather and how it behaves. Any thoughts on next Sat? Little concerned that maybe I should reschedule flight into for Monday the 14th.

Looking at the models, current thinking based on the GFS, FIM and GGEM models, the trough will take on a negative tilt as the storm gets going. The euro is not as strong.   MPX has found that the FIM has been one of the better models this season, at least at this latitude, and has quoted it often in their AFD's.  While MPS's ability  to move snow is legendary and impressive, you may want to consider a Friday or Monday arrival time.  Btw the 6z GFS does become negatively titled. 

 

To quote from MPX:

 

CYCLOGENESIS OVER THE TX PANHANDLEWILL PRODUCE A SURFACE LOW THAT COULD DEVELOP IN A NUMBER OF WAYSDEPENDING ON THE EVOLUTION OF THE WESTERN TROUGH AND ITSINTERACTION WITH A TIGHTENING BAROCLINIC ZONE. IF MORE ENERGY CANEJECT NORTHEAST WITH THE STORM AND ALLOW IT TO BECOME NEGATIVELYTILTED...A VERY POWERFUL WINTER STORM WOULD RESULT FOR THECENTRAL PLAINS INTO UPPER MIDWEST AND WESTERN GREAT LAKES WITHHEAVY SNOW ACCUMULATIONS AND BLIZZARD CONDITIONS. THE FIM MODELHINTS TOWARD THAT SOLUTION. IF THE GFS AND EC ARE RIGHT AND ASIZABLE PORTION OF THE ENERGY REMAINS LOCKED OVER THE SOUTHWESTERNU.S...A MORE POSITIVELY TILTED SYSTEM WOULD BRING MUCH LIGHTERACCUMULATIONS. FOR NOW...BUMPED UP POPS INTO THE MEDIUM RANGESATURDAY. THIS PATTERN WILL NEED TO BE WATCHED VERY CLOSELY.
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There's like a 50 degree spread in temps/dewpoints between C IA/C IL on the 00z Euro at 144 hours.

 

Just took a close look at that.  temps range from 60 near Peoria/Springfield IL to 10 near Des Moines/Waterloo IA.  Here we crash from 55 at noon to 25 at 6pm, and near 10 at midnight.  Snow or no snow that would make for a very interesting storm system.  Gonna be a fun week ahead.  :popcorn:

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I don't know what's wrong with the forum but I can't quote stuff correctly anymore. Anyways just wanted to give a POP to the board for my forecast so far. I chose Detroit as the verification point. I added numeric labels into the old posts to keep track of the dates.

 

Event 1 temps drop from mid 40's to upper 30's during the week to a high of 33 on sat.

Event 2 temps did cool about 4-5 degrees as a front came through from mid 30's to high of 28. Notice overnight low of around 12F

Event 3 temps drop from 30 on Jan 1 to a high of 24 on Jan 2...coldest afternoon air of season so far. (good shot of cold)

Event 4 temps warm from a high of 24 on Jan 2 to a high of 36 on Jan 6....12F warm up

Event 5 we saw a high of 36 yesterday and the forecast was for todays high to be 32 at DTW but we are up to 34 so far so it's definitely a bust on the magnitude of the cool down but I posted the 850 chart from last night 0z and you can see there is a pocket of colder air at 850 that moved over the region (not same cold air mass from Jan 2 event)...it just didn't translate to the surface. And all my forecasts I note that the forecast is referencing warm up/cool down of 850 temps unless I say at the sfc. 

Thanks so much guys! Here ya go!

'QVectorman', on 13 Dec 2012 - 14:48, said:snapback.png

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 1) 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 2)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 3)good shot of colder air Dec 30-Jan 3.

'QVectorman', on 14 Dec 2012 - 16:54, said:snapback.png

With the newest GWO numbers today the latest analogs indicate a 15-20F 4)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 5) spell of colder air Jan 5-8.

 

'QVectorman', on 21 Dec 2012 - 12:37, said:snapback.png

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 

 

post-3697-0-18121600-1357582331_thumb.jp

post-3697-0-45673300-1357582345_thumb.jp

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QVectorman had hit on this a few pages back, but I'll post something again I did awhile back. 6"+ snowstorms at MDW and MJO phase (since Fall 1974). Bottom chart is by what phase the storm started in, FYI. Amplitude of the MJO is not considered in this exercise. 

 

 

 

Seems most of the guidance, for this first time in a long time, is taking it through phases 5-6 and then possibly into phase 7-8...with some amplitude. As you can see, these are more favorable for bigger snow events at MDW...especially in DJF. Just one piece of the puzzle though.

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QVectorman had hit on this a few pages back, but I'll post something again I did awhile back. 6"+ snowstorms at MDW and MJO phase (since Fall 1974). Bottom chart is by what phase the storm started in, FYI. Amplitude of the MJO is not considered in this exercise. 

 

attachicon.gifMDW SNOWFALL:MJO A.png

 

attachicon.gifMDW SNOWFALL:MJO B.png

 

Seems most of the guidance, for this first time in a long time, is taking it through phases 5-6 and then possibly into phase 7-8...with some amplitude. As you can see, these are more favorable for bigger snow events at MDW...especially in DJF. Just one piece of the puzzle though.

 

I found your data quite interesting. After reading HM's post, you do see he has solid reasoning to say it could turn snowy here with phases 6-8. Usually we associate phase 6 and 7 as mild in this region. Probably varies with ENSO, but that seems to be the phases for snowstorms in the Great Lakes. Couple that with a rising PNA and we could be seeing some really active weather after this weekend.

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The Euro seems to be trending towards a more consolidated upper trough with each run, the 12z was pretty close to a really big solution with the second system.

All models are very close to that big solution.  They all seem to have a sub 1000mb low get established over Western Kansas, Eastern CO.  At which point the 850mb winds originate over the desert sw, although they are around 50knts or so, they are bone dry, so therefore the surface system weakens dramatically.  Imo  what we need to happen is have the H85-700mb south eastern ridge back off by about 300 miles or so, as that would allow a bit more of a flow out of the Gulf.

 

As to the question of the cold air ever getting into the lower 48, the Euro is right on time:

 

12zeurohourly850mbTempAnomalyNA240.gif

 

looks like a cross polar flow to me, once the clipper system moves out the dogs can be released, I know it's 10 days out, but the timing is right.

 

12zeuro850mbTSLPUS240.gif

 

time_pres_TEMP_ANOM_JFM_NH_2013.gif

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All models are very close to that big solution.  They all seem to have a sub 1000mb low get established over Western Kansas, Eastern CO.  At which point the 850mb winds originate over the desert sw, although they are around 50knts or so, they are bone dry, so therefore the surface system weakens dramatically.  Imo  what we need to happen is have the H85-700mb south eastern ridge back off by about 300 miles or so, as that would allow a bit more of a flow out of the Gulf.

 

IMO it's the backside waves that are playing havoc as to what really happens. 

 

at 90hr it has the look of a big system about to get going

 

 

but by 102hr you and several smaller waves come flying down the backside and mess with the orientation and eventual placement of the first ULL dropping down

 

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Yesterday there was a CCKW over 120E which is equivalent to phase 6 of the MJO that may trigger the teleconnection pattern that will produce the Jan 14-15 storm over the plains/midwest. Also another factor is an extra tropical rossby wave train that is clipped on the analysis at 30N 170W that will move over the central portion of the country Jan 14-15 time frame. So both the CCKW and x-t RW should contribute to generating a decent short wave Jan 14-15. This is an identical set up and timing with CCKW and xt RWT to the Dec. 26th snow storm that hit the Midwest/Great Lakes. IF a big IF, if the MJO makes it to phase 7 around Jan 13/14(Ventrice site) or Jan 15/16 (CPC models) depending on what site given a 7-10 day lag we could see another storm for the east coast for Jan 20-23 or Jan 22-25 which jives with my Jan 21-25 or Jan 24-27 that I posted back on Dec. 20th. I like my dates from a month ago for shortwaves for time frame Jan 21-25 and another  wave jan 24-27 so I think the MJO forecast will change a few times in the next couple days eventually falling in line with GWO dates which are the dates from Dec. 20. Which makes sense since the GWO impacts the MJO and vice versa. 

post-3697-0-88137300-1357589495_thumb.jp

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IMO it's the backside waves that are playing havoc as to what really happens. 

 

at 90hr it has the look of a big system about to get going

 

attachicon.gif90hr.gif

 

but by 102hr you and several smaller waves come flying down the backside and mess with the orientation and eventual placement of the first ULL dropping down

 

attachicon.gif102hr.gif

 

I saw that as well this morning, without posting maps of the 06/12z GFS differences, that appears to be caused by the difference in the way the model treats the ridge axis in the Gulf of AK. ( I use the word appears b/c i'm not 100% sure.)  Yet on the other hand the GFS, Euro, and GGEM have anywhere from a 995 to 998 mb surface low forming in reaction to the lead wave of energy, but with no moisture to work with it almost drys up.  Not sure if the cause of this is the back side waves or the southeastern ridge, at any rate it just looks a bit strange to my amateur eye.  

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IMO it's the backside waves that are playing havoc as to what really happens. 

 

at 90hr it has the look of a big system about to get going

 

attachicon.gif90hr.gif

 

but by 102hr you and several smaller waves come flying down the backside and mess with the orientation and eventual placement of the first ULL dropping down

 

attachicon.gif102hr.gif

The question is if we can get a setup where those waves either don't affect it, or actually help with it's evolution, both scenarios would probably involve the lead trough digging further south (or at least going by trends with the ensemble members that end up bombing out).

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Yesterday there was a CCKW over 120E which is equivalent to phase 6 of the MJO that may trigger the teleconnection pattern that will produce the Jan 14-15 storm over the plains/midwest. Also another factor is an extra tropical rossby wave train that is clipped on the analysis at 30N 170W that will move over the central portion of the country Jan 14-15 time frame. So both the CCKW and x-t RW should contribute to generating a decent short wave Jan 14-15. This is an identical set up and timing with CCKW and xt RWT to the Dec. 26th snow storm that hit the Midwest/Great Lakes. IF a big IF, if the MJO makes it to phase 7 around Jan 13/14(Ventrice site) or Jan 15/16 (CPC models) depending on what site given a 7-10 day lag we could see another storm for the east coast for Jan 20-23 or Jan 22-25 which jives with my Jan 21-25 or Jan 24-27 that I posted back on Dec. 20th. I like my dates from a month ago for shortwaves for time frame Jan 21-25 and another  wave jan 24-27 so I think the MJO forecast will change a few times in the next couple days eventually falling in line with my dates from Dec. 20. 

attachicon.gifsun.jpg

Thanks for your insight and lending your knowledge to this sub forum, its much appreciated.  Sometimes I wished we had more pro mets join us.  Good luck with your forecast.  I have so much to learn about the KW thing.

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The question is if we can get a setup where those waves either don't affect it, or actually help with it's evolution, both scenarios would probably involve the lead trough digging further south (or at least going by trends with the ensemble members that end up bombing out).

 

This is the one we need and where all the energy and main jet streak is at the base of the trof, not where the ULL scoots northeastward quickly. 

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This is the one we need and where all the energy and main jet streak is at the base of the trof, not where the ULL scoots northeastward quickly. 

So Thunder are you saying that the back side waves are pushing the lead energy out to quickly?  If you are that makes sense to me and may very well be the reason the surface cyclone doesn't have any moisture to work with.

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Anyone else liking the 16-18 time period for a snowstorm in the OV? GFS has been showing something including a monster apps runner that the 12z showed and 0z GGEM at hour 240 as the looks of an apps runner as well.

right before that on the 13/14th GFS has been showing a Potential snowstorm for parts of the Midwest off and on for the past couple days now

Sent from my iPhone 5 using

Tapatalk!

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Heh, FWIW the 18z op GFS brings the LOT CWA a few inches of snow Sunday into Sunday night, but then again at the same time, the 12z Euro has a big 1035 mb high over the region. Will be at least mildly interesting to see if what the GFS is currently showing lasts for more than 1 or 2 cycles. 

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Thanks for your insight and lending your knowledge to this sub forum, its much appreciated.  Sometimes I wished we had more pro mets join us.  Good luck with your forecast.  I have so much to learn about the KW thing.

 

NP glad to have a great discussion with everyone and a good exchange of ideas and thoughts!

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Looking at the models, current thinking based on the GFS, FIM and GGEM models, the trough will take on a negative tilt as the storm gets going. The euro is not as strong.   MPX has found that the FIM has been one of the better models this season, at least at this latitude, and has quoted it often in their AFD's.  While MPS's ability  to move snow is legendary and impressive, you may want to consider a Friday or Monday arrival time.  Btw the 6z GFS does become negatively titled. 

 

Thank you , Will take advice under consideration I'm thinking maybe 24 more hrs ? maybe will help, grrrrrrrrrrrr. but the weather nut in me so wants to see a MN Blizzard up close and personal  !!!! lol.... 

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Heh, FWIW the 18z op GFS brings the LOT CWA a few inches of snow Sunday into Sunday night, but then again at the same time, the 12z Euro has a big 1035 mb high over the region. Will be at least mildly interesting to see if what the GFS is currently showing lasts for more than 1 or 2 cycles. 

 

It wasn't all that different from the 12z run and has some ensemble support.  I wouldn't be shocked if the 0z run continues to advertise something similar or even wetter but with the Euro so far off, it's hard to get too jazzed.

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It wasn't all that different from the 12z run and has some ensemble support.  I wouldn't be shocked if the 0z run continues to advertise something similar or even wetter but with the Euro so far off, it's hard to get too jazzed.

 

Yup, agreed, 18z was just shifted a bit northwest from 12z and slightly wetter, but would like to see the Euro get on board. 

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Yup, agreed, 18z was just shifted a bit northwest from 12z and slightly wetter, but would like to see the Euro get on board. 

 

The Euro is bombing out the initial low, pushing the cold front clear off the East Coast, while the GFS keeps it more diffuse / disorganized.  It seems like there's a timing difference between the two models even earlier on so who knows which one is better.

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Nice to see NWS on board with time frames everyone has been throwing around on here.000FXUS61 KBUF 080253AFDBUFAREA FORECAST DISCUSSIONNATIONAL WEATHER SERVICE BUFFALO NY953 PM EST MON JAN 7 2013

 

THE SECOND PATTERN CHANGE WILL BEGIN TO SHOW ITS CARDS BY THE MIDDLEOF THE MONTH. A MAJOR SUDDEN STRATOSPHERIC WARMING EVENT IS UNDERWAYAND NEARING COMPLETION. SUDDEN STRATOSPHERIC WARMING EVENTS AREFAVORED TO OCCUR DURING AN EASTERLY PHASE OF THE QUASI-BIENNIALOSCILLATION /QBO/...WHICH IS THE PHASE THE STRATOSPHERE IS IN THISWINTER. THE SUDDEN STRATOSPHERIC WARMING CAUSES A DRAMATICWEAKENING...AND SOMETIMES ENTIRE BREAKDOWN OF THE STRATOSPHERICPOLAR VORTEX...AND A GREAT WEAKENING OR EVEN REVERSAL OF THESTRATOSPHERIC POLAR NIGHT JET. THE GFS FORECASTS THIS TO OCCUR OVERTHE NEXT WEEK AT THE 2MB LEVEL.THE RESULT OF ALL OF THIS IS THE GENERATION OF STRONG HIGH LATITUDEBLOCKING AS THE DRAMATIC CHANGES IN THE STRATOSPHERE FEED DOWN INTOTHE TROPOSPHERE. HIGH LATITUDE BLOCKING FORCES THE COLDEST AIR SOUTHOUT OF THE HIGH ARCTIC AND TOWARDS THE MID LATITUDES...AND ALSOFAVORS LASTING STRONGLY NEGATIVE EPISODES OF ARCTIC OSCILLATION /AO/AND NORTH ATLANTIC OSCILLATION /NAO/. THIS TYPICALLY BEGINS TO TAKEPLACE 10-15 DAYS AFTER THE SUDDEN STRATOSPHERIC WARMING EVENT. HOWLONG IT LASTS CAN VARY...BUT TYPICALLY THE COLD PATTERN LASTS FOR ATLEAST A FEW WEEKS...AND OCCASIONALLY CAN PERSIST THROUGH THE REST OFWINTER.AS ALL OF THIS IS OCCURRING...THE MJO IS FORECAST BY THE GEFSENSEMBLES TO WEAKEN AND FADE AWAY IN ABOUT 10 DAYS. THE PACIFICNORTH AMERICAN PATTERN /PNA/ IS FORECAST TO REMAIN NEGATIVE OVER THENEXT 10 DAYS...WHICH WILL DIRECT THE FIRST BATCHES OF COLD INTO THEWESTERN AND EVENTUALLY CENTRAL UNITED STATES. GEFS ENSEMBLE MEMBERSSUPPORT A TREND TOWARDS A NEUTRAL OR POSITIVE PNA BY THE MIDDLE OFTHE MONTH...WHICH SHOULD ALLOW THE GROWING COLD TO SPREAD EASTWARD.WHAT ALL OF THIS TECHNICAL JARGON MEANS IS THAT THERE IS MODERATE TOHIGH CONFIDENCE IN A PATTERN CHANGE TOWARDS MUCH COLDER WEATHER FORTHE CENTRAL AND EASTERN UNITED STATES STARTING AROUND THE MIDDLE OFJANUARY...WITH COLD LIKELY PEAKING IN LATE JANUARY INTO EARLYFEBRUARY. THERE IS THE POTENTIAL FOR THE COLDEST AIR WE HAVE SEEN INAT LEAST SEVERAL YEARS DURING THIS PERIOD. WHAT SNOW POTENTIAL THISWILL BRING IS MUCH MORE UNCERTAIN DUE TO UNKNOWN DETAILS WITHSYNOPTIC STORM TRACK AND LAKE EFFECT POTENTIAL.
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