SpartyOn Posted January 10, 2013 Share Posted January 10, 2013 The Euro has a weird retro-grade look to it.... The cold appears to head east, then switches directions and comes back. Probably a good bet that the Euro will win out on this cold snap. The GFS has a small issue blowing the cold out of the water and over doing it. Link to comment Share on other sites More sharing options...
Jonger Posted January 10, 2013 Share Posted January 10, 2013 Probably a good bet that the Euro will win out on this cold snap. The GFS has a small issue blowing the cold out of the water and over doing it. Both models are pretty similar, the Euro is a bit warmer... But the same idea is there. Link to comment Share on other sites More sharing options...
Jonger Posted January 10, 2013 Share Posted January 10, 2013 Supposed to hit the -40's in Winnipeg. Link to comment Share on other sites More sharing options...
Geos Posted January 10, 2013 Share Posted January 10, 2013 That's probably good that the EURO doesn't bring the core of the cold down. Too much cold kills snow chances including LES. Link to comment Share on other sites More sharing options...
Hoosier Posted January 10, 2013 Share Posted January 10, 2013 I'd expect model flip flops with the magnitude of the cold given such a tight gradient. I mean obviously the core of the cold is going to stay in Canada for the forseeable future but I wouldn't be surprised to see the Euro go colder again. The southwest cutoff low could also play a role...the stronger that is, the harder it may be for the cold to come south. Link to comment Share on other sites More sharing options...
Jonger Posted January 10, 2013 Share Posted January 10, 2013 That's probably good that the EURO doesn't bring the core of the cold down. Too much cold kills snow chances including LES. The big LES outbreak in Dec 2001, the high temps were in the upper teens to low 20's. So this is true. Link to comment Share on other sites More sharing options...
roardog Posted January 10, 2013 Share Posted January 10, 2013 The big LES outbreak in Dec 2001, the high temps were in the upper teens to low 20's. So this is true. If it gets too cold, the snow is like dust. It reduces visibilities but doesn't accumulate much. Sometimes the flakes are so small, you can't tell if it's snowing or just blowing snow off the ground. Link to comment Share on other sites More sharing options...
Geos Posted January 10, 2013 Share Posted January 10, 2013 The big LES outbreak in Dec 2001, the high temps were in the upper teens to low 20's. So this is true. Yeah you start to get Delta Ts over 24°C then you chances go downhill. I've seen snow at -3°F about, but it was very fine and didn't accumulate that well. Link to comment Share on other sites More sharing options...
ValpoVike Posted January 10, 2013 Share Posted January 10, 2013 Yeah you start to get Delta Ts over 24°C then you chances go downhill. I've seen snow at -3°F about, but it was very fine and didn't accumulate that well. I apologize in advance if this turns out as a double post, having issues for some reason. But, you're right on. Delta T's in the low 20's, moderate wind speed, long fetch, and temps in the mid-upper teens can produce some spectacular snowfall rates, at least from my experiences living in Geauga county Ohio. Here in Valpo, it takes more than that - a lephrechaun, a rabbits foot, alignment of the stars, and wind fields that don't shift more than 5 degrees from the sweet spot. Link to comment Share on other sites More sharing options...
QVectorman Posted January 10, 2013 Share Posted January 10, 2013 Newest CCKW map shows the extra tropical rossby wave train at 155W 30N and the one continuing to develop at 150E 20N along with the CCKW at 165E 0N. Still on schedule the 155W RW should move over the eastern US on Jan 15-16 and the 150E should pass over the eastern US Jan. 22-23. Also watching the GWO, the analogs are pointing to an arctic blast of air possible Jan 24-27 or Feb 2-4. I'm leaning more towards the 24-27 time frame since it coincides with the 2-3 week window after the SSW->PV split yesterday. Obviously models aren't feeling this yet. They are all over the place anyways but I think they will come around in the end. Still falls in line with thoughts back on the the 5th that Jan 25-30 could see -33C 850 tmps sneaking over the northern plains or GLKS or NE. Link to comment Share on other sites More sharing options...
SpartyOn Posted January 10, 2013 Share Posted January 10, 2013 Newest CCKW map shows the extra tropical rossby wave train at 155W 30N and the one continuing to develop at 150E 20N along with the CCKW at 165E 0N. Still on schedule the 155W RW should move over the eastern US on Jan 15-16 and the 150E should pass over the eastern US Jan. 22-23. Also watching the GWO, the analogs are pointing to an arctic blast of air possible Jan 24-27 or Feb 2-4. I'm leaning more towards the 24-27 time frame since it coincides with the 2-3 week window after the SSW->PV split yesterday. Obviously models aren't feeling this yet. They are all over the place anyways but I think they will come around in the end. Still falls in line with thoughts back on the the 5th that Jan 25-30 could see -33C 850 tmps sneaking over the northern plains or GLKS or NE. tues2.jpg -33 850s sounds incredible. Link to comment Share on other sites More sharing options...
QVectorman Posted January 10, 2013 Share Posted January 10, 2013 Well the 12z Euro has -36C in Maine for 1/19 12z and 12z GFS has -36C in northern MN at 12z for 1/20. And those types of temps have been showing up from time to time on the runs. That's obviously not the 24-27 time frame but gives credence that the models believe it's physically possible to achieve those type of temps in the next couple weeks. Plus as I recall the GFS was indicating these types of 850 temps arriving for Jan 15-16 back a week ago which now has been pushed back to the 19th. I mentioned previously that I thought that the models last week were rushing the coldest air in too soon. I still think that and think we will see this coldest air delayed again by the models for another 4-5 days til the at least the 24th Link to comment Share on other sites More sharing options...
frostfern Posted January 11, 2013 Share Posted January 11, 2013 If it gets too cold, the snow is like dust. It reduces visibilities but doesn't accumulate much. Sometimes the flakes are so small, you can't tell if it's snowing or just blowing snow off the ground. If it's too cold the DGZ goes underground. Link to comment Share on other sites More sharing options...
michsnowfreak Posted January 11, 2013 Share Posted January 11, 2013 With our snowpack being destroyed by this thaw and the cold coming in, I am starting to get a LITTLE worried we have one of those bare ground/cold periods. We havent really had those lately, and they are way more common then you might think. Everyone knows Im the stats guy, but in my time looking at old weather records, keep in mind a lot of the "non-interesting" stuff never gets posted. I cannot BELIEVE how many times over the years arctic blasts have been met with little or no snowcover. Below are just a few of the more longer lasting blasts of cold (by this I mean highs in the teens or colder) that had no real snowcover at Detroit. Of course there also were tons of other 1 and 2 day stretches with highs in the teens or lower with no snowcover, and even some of the most notorious coldwaves had very light snowcover. The Dec 1989 arctic blast had a snow depth of mostly around 2". The Feb 1934 arctic blast had a depth of T-1". The brutal Feb 1899 cold wave had snow depth of 1-2". I could go on. And also, many of our deep snowcover times (many, not all) are in periods of more seasonable cold rather than arctic cold. Does this mean I think this bare ground/arctic air combo will happen this time around? No, I dont think it will be THAT cold for more than a few days and I dont think we will get less than an inch of snow with active Lakes. But its some scary food for thought! ....................High....Low....Snowdepth 12-25-1899….17…11….T 12-26-1899….18…..9….T 12-27-1899….20…12….T 12-28-1899….20…10….T 12-29-1899….14…..6….T 12-30-1899…..8…...0….T 12-31-1899….12…..4….T 01-01-1900….19…..5….T 02-05-1942.....12......2.....T 02-06-1942.....22......0.....T 02-07-1942.......3.....-5.....T 02-08-1942.......7.....-4.....T 02-09-1942.....16......6.....T 02-10-1942.....14.....-2.....T 01-21-1961.....18......6......T 01-22-1961.....14......3......T 01-23-1961….18…..3…..T 01-24-1961….15…..0…..T 01-25-1961….18….-1…..T 01-26-1961….15…10…..T 01-30-1996.....17......8......0 01-31-1996.....16......2......0 02-01-1996.....15......1......0 02-02-1996.....10.....-2......0 02-03-1996.......8.....-7......0 02-04-1996.....11.....-5......0 02-05-1996.....22......0......0 Link to comment Share on other sites More sharing options...
QVectorman Posted January 11, 2013 Share Posted January 11, 2013 Josh what did 94 look like? Can't believe you forgot 94!!!! -25f in Detroit Link to comment Share on other sites More sharing options...
dmc76 Posted January 11, 2013 Share Posted January 11, 2013 Josh what did 94 look like? Can't believe you forgot 94!!!! -25f in Detroit Oh I remember. -5 for the high one day. 2 days off from school. Wind chills reached near -50. Wicked Cold for these parts. Link to comment Share on other sites More sharing options...
TimChgo9 Posted January 11, 2013 Share Posted January 11, 2013 I am listening to the rain pelting my roof.. The most depressing sound ever. Calender says January 10th, weather outside says late March. Reading about the potential cold though, does make for a nice distraction from the rain. Positively miserable out there tonight. Link to comment Share on other sites More sharing options...
michsnowfreak Posted January 11, 2013 Share Posted January 11, 2013 Josh what did 94 look like? Can't believe you forgot 94!!!! -25f in Detroit Oh I didnt forget it...I was mainly focusing on arctic blasts that featured no snowcover, 1994 had decent snow depth. Jan 19, 1994 is officially Detroits coldest day on record (hi -4, lo -20). The unofficial coldest temp is -24F in Dec 1872 but records (without some error) officially begin in 1874. Detroits low temps of -15F or colder and corresponding snowcover (I will rank in order simply of coldest Low). Looks like all the big daddys of cold waves had firm snowpack. .....................High.....Low....Snowcover 01-21-1984......1......-21.......3" 01-19-1994.....-4......-20.......8" 02-09-1875......?......-20.......? 01-18-1976.....11.....-18.......5" 01-12-1918.....26.....-16.......7" 02-05-1918.....13.....-16.......9" 01-25-1897.......2.....-16.......5" 01-15-2009.......3.....-15.....10" 01-18-1994.......1.....-15.......8" 02-03-1985.....16.....-15.......6" 01-17-1982......-1.....-15.......4" 02-14-1905.....13.....-15.....16" 01-03-1879.......7.....-15.......? Link to comment Share on other sites More sharing options...
OHweather Posted January 11, 2013 Share Posted January 11, 2013 Well the 12z Euro has -36C in Maine for 1/19 12z and 12z GFS has -36C in northern MN at 12z for 1/20. And those types of temps have been showing up from time to time on the runs. That's obviously not the 24-27 time frame but gives credence that the models believe it's physically possible to achieve those type of temps in the next couple weeks. Plus as I recall the GFS was indicating these types of 850 temps arriving for Jan 15-16 back a week ago which now has been pushed back to the 19th. I mentioned previously that I thought that the models last week were rushing the coldest air in too soon. I still think that and think we will see this coldest air delayed again by the models for another 4-5 days til the at least the 24th The 0z GFS fits your idea well...shows a couple of cold shots (-20C at 850mb south of the boarder) during the latter portions of next week and then again around the 20th...but then drives -30C 850's into the lower lakes on the 26th. Link to comment Share on other sites More sharing options...
QVectorman Posted January 11, 2013 Share Posted January 11, 2013 The 0z GFS fits your idea well...shows a couple of cold shots (-20C at 850mb south of the boarder) during the latter portions of next week and then again around the 20th...but then drives -30C 850's into the lower lakes on the 26th. Dang! I need to check that run out ASAP...lol. Of course as we all know we won't that solution again until 2 days before the event! Wawa! Edit: Add...GEEEZZZ -31C at DTW. Nice! Link to comment Share on other sites More sharing options...
BowMeHunter Posted January 11, 2013 Share Posted January 11, 2013 Remy LaCroix 00z gfs Link to comment Share on other sites More sharing options...
OHweather Posted January 11, 2013 Share Posted January 11, 2013 Models toying with the idea of extreme cold across the region during the last week to 10 days of January…is the idea realistic, and will there be storm chances to go along with the cold? The current pattern is a torchy one across the eastern half of the CONUS into eastern Canada…however, some changes are occurring which will bring cold to the sub-forum. Ridging is nosing into Alaska and the AO is beginning to fall with heights rising over the North Pole. A polar vortex is currently over northeastern Canada with an east based –NAO (responsible for a recent and rare Jerusalem snowstorm) located between Iceland and England. A very strong Asian-Pacific jet, breaking over the central Pacific in conjunction with a strong Asian polar vortex support heights continuing to rise into Alaska. The positioning of tropical convection (Indian Ocean and Western Pacific) in combo with the location of this vortex, which has become a bit of a main stay this fall and winter, support the Asian-Pacific jet remaining quite strong but breaking east of the date-line. This supports above normal heights over Alaska which most modeling agrees on: The progression of the MJO through phase 6 and into phase 7 over the next week supports convection remaining west of the dateline, which also supports ridging continuing to build into Alaska thanks to a strong Asian-Pacific jet breaking over the central Pacific. The 18z GFS, valid 12z/the 16th continues to show this occurring: This period of ridging trying to build over the far western portion of the continent should direct a nice shot of cold aimed towards the Upper Midwest near the middle of next week as the polar vortex dislodges south somewhat towards southern Hudson Bay, which the GFS and European ensembles do agree on: However, blocking over the arctic will still be pretty weak and this cold shot probably won’t penetrate south of the Great Lakes, and will only be seasonably cold. A bit of a cross-polar flow will develop next week but the polar vortex will be too far north to allow true arctic air to spill south of the boarder…it will likely just be a parting blow. The European ensembles agree on a closed low ejecting out of the west in this timeframe…if it ejects at the right to time get caught by a shortwave rotating around the west side of the vortex there may be some sort of a storm over the lower lakes/Ohio Valley…but right now it appears the PV will be a bit too far north thanks to a lack of robust blocking to allow this to work out…however as the arctic air spills south it will likely be accompanied by a strong front with some snow showers and some lake effect should flare up behind it so the Great Lakes and Upper Midwest should be re-covered by a light blanket of snow where the snow cover disappears (or has disappeared) but it probably won’t be a significant amount of snow. Despite the strongest portion of the Pacific jet being focused to our west, the energy currently contained in the extremely strong jet streak will probably flatten ridging over the far western portions of N. America enough to see a brief moderating trend at some point, perhaps next weekend. However, as the jet relaxes some (see the second western Pac GFS image I posted above) ridging should build back into Alaska and we shouldn’t see more than a brief period of above average temps. The polar vortex will also remain displaced fairly far south and poised to deliver more cold. The stratospheric warming has successfully disrupted the stratospheric vortex at all levels. The question is will this propagate downward, and how soon will this occur? By day 10, the GFS and ECM ensembles (12z Thursday) both show heights rising over the North Pole. This is likely the start of the stratospheric warming propagating into the troposphere. There is typically a 1-3 week lag between a stratospheric warming/vortex split and impacts on the troposphere, if they occur, and this is right in that time period. Although there is considerable spread amongst the GFS ensemble members, most members keep the AO negative through the forecast period with a few members showing a severely negative AO developing: How efficient this is in producing cold over the Great Lakes/Ohio Valley remains to be seen, and is likely dependent on the Pacific pattern not going too zonal. If we see convection remain just west of the dateline…that should support continued ridging into Alaska, however, if the MJO completely dies that may allow the pattern over the Pacific to flatten out a little bit. The GFS suite keeps the MJO a bit stronger while stalling it in phases 6-7 than the ECM suite which shows it crashing a bit harder. I’m certainly not a GWO/GLAAM expert however…the most momentum appears to be shifting southward, currently focused near 30N but trending south…and the GLAAM appears to be rising towards neutral. If we see this trend continue, it may support the GLAAM moving into phase 5 at a moderate amplitude which supports convection near the dateline…this would allow ridging to continue into Alaska/western Canada and perhaps help facilitate a cross polar flow with ridging developing over the North Pole. This does however have implications…if the convection does remain west of the dateline, that would continue to focus the heart of the cold towards the upper Plains which would leave room for a storm track into the Ohio Valley if the sub-tropical jet becomes more active…which may occur if the GLAAM does make strides closer to more El Nino like phases. However, if the convection does eventually propagate east of the dateline the storm track would shift east and the focus would be towards the eastern end of this sub-forum and into the Mid-Atlantic/New England. Right now though I’d favor the pattern remaining amplified enough to capitalize on the falling AO… I’m going with a glancing cold shot Wednesday-Friday with rather insignificant fan-fare…a brief moderation next weekend and then another cold shot, perhaps with a bit better penetration into the CONUS and more longevity around the 21st and 22nd. This cold retreats briefly perhaps around the 24th-25th before we see another, much more significant cold shot aimed at the Plains/upper Midwest around the 26th-27th as the MJO perhaps attempts to get going again and re-amplifying the Pacific Pattern and a potential classic cross-polar flow developing over western Canada. With the sub-tropical jet perhaps becoming a bit more active there may be room for an Ohio Valley runner in this time frame although we will be walking a fine line with potential suppression. Recent trends amongst the GFS/Euro ensembles were used to aid in the timing mentioned above, FYI. 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RCNYILWX Posted January 11, 2013 Share Posted January 11, 2013 Bringing the goods as always OHweather, thanks for the fantastic analysis. Link to comment Share on other sites More sharing options...
QVectorman Posted January 11, 2013 Share Posted January 11, 2013 Great discussion I would add about the SSW propagating I believe as others have forecasted it will propagate looking at the EP flux vectors. They were pretty strong for the last 2 days in the poleward direction. I'm thinking it will be enough. Time will tell I guess! Also you're concerns about the MJO are legit Mike Ventrice has shed some light on this issue over the past few days...sorry quotes don't work for some reason from other threads in Chrome. This was a great discussion! I'm glad to see this in a NWS WFO discussion. This discussion is in agreement with what Adam and I spoke about on this forum in December. The only thing that concerns me is the discussion of the weakening of the MJO event... Most dynamical and statistical models will always show a weakening of the MJO when it tranverses around the Western Hemisphere. In this case, the dynamical models hold onto this MJO signal, but statistical approaches like Paul Roundy's will show a weakening of the MJO over the Western Hemisphere. This weakening is not a true weakening, and is a biproduct of the MJO speeding up over the Western Hemisphere, taking the shape of a strong convectively-coupled Kelvin wave. Therefore, space-time filtering techinques (like Paul's) will weaken MJO filtered anomalies and replace them with Kelvin filtered anomalies. Agreed, though while convection might turn off over the "convectively dead regions" such as the East Pacific and Atlantic ITCZ, the upper-level circulation associated with the MJO contineus progressing eastward with time. Incorporating U200 into RMM is why RMM is capable of detecting MJO-related signals over the Western Hemisphere. The semi-loop that many of the models are suggesting very well may happen in RMM phase 7. However, this doesnt necessarily mean the MJO is weakening... it is just most likely associated with noise projecting onto the RMM PCs. According the space-time filtered VP850, the core of the MJO signature appears to be centered about 150E. In a week, it should be located east of the dateline, two weeks over the East Pacific, and three weeks back over the Indian. There is potential for the development of an oceanic Kelvin wave that could couple convection. If this were the case, there could be two cores of equatorial convection when the MJO signal gets back over the Indian Ocean. One core associated with the MJO, the second associated with the oceanic Kelvin wave. The development of this oceanic Kelvin wave could throw off some of the extra-tropical circulation signals we commonly acustom with an MJO phase 1-3. Something to keep an eye on. Link to comment Share on other sites More sharing options...
OHweather Posted January 11, 2013 Share Posted January 11, 2013 Bringing the goods as always OHweather, thanks for the fantastic analysis. Thanks! Great discussion I would add about the SSW propagating I believe as others have forecasted it will propagate looking at the EP flux vectors. They were pretty strong for the last 2 days in the poleward direction. I'm thinking it will be enough. Time will tell I guess! Also you're concerns about the MJO are legit Mike Ventrice has shed some light on this issue over the past few days...sorry quotes don't work for some reason from other threads in Chrome. This was a great discussion! I'm glad to see this in a NWS WFO discussion. This discussion is in agreement with what Adam and I spoke about on this forum in December. The only thing that concerns me is the discussion of the weakening of the MJO event... Most dynamical and statistical models will always show a weakening of the MJO when it tranverses around the Western Hemisphere. In this case, the dynamical models hold onto this MJO signal, but statistical approaches like Paul Roundy's will show a weakening of the MJO over the Western Hemisphere. This weakening is not a true weakening, and is a biproduct of the MJO speeding up over the Western Hemisphere, taking the shape of a strong convectively-coupled Kelvin wave. Therefore, space-time filtering techinques (like Paul's) will weaken MJO filtered anomalies and replace them with Kelvin filtered anomalies. Agreed, though while convection might turn off over the "convectively dead regions" such as the East Pacific and Atlantic ITCZ, the upper-level circulation associated with the MJO contineus progressing eastward with time. Incorporating U200 into RMM is why RMM is capable of detecting MJO-related signals over the Western Hemisphere. The semi-loop that many of the models are suggesting very well may happen in RMM phase 7. However, this doesnt necessarily mean the MJO is weakening... it is just most likely associated with noise projecting onto the RMM PCs. According the space-time filtered VP850, the core of the MJO signature appears to be centered about 150E. In a week, it should be located east of the dateline, two weeks over the East Pacific, and three weeks back over the Indian. There is potential for the development of an oceanic Kelvin wave that could couple convection. If this were the case, there could be two cores of equatorial convection when the MJO signal gets back over the Indian Ocean. One core associated with the MJO, the second associated with the oceanic Kelvin wave. The development of this oceanic Kelvin wave could throw off some of the extra-tropical circulation signals we commonly acustom with an MJO phase 1-3. Something to keep an eye on. fluxes.gif Thanks for the input. I was looking for those EP flux vectors and hadn't found them off a quick search. I'm glad they're poleward, certainly favors the SSW propigating into the troposphere. Link to comment Share on other sites More sharing options...
OHweather Posted January 11, 2013 Share Posted January 11, 2013 12z GFS and its ensembles certainly put all their eggs in the second shot of arctic air being the coldest as opposed to the third one. That is still almost a good 10 days out however, so we'll see if the GFS suite modifies the second shot 21st-22nd like it did to the blast we are going to see next week as we get closer. Link to comment Share on other sites More sharing options...
Hoosier Posted January 11, 2013 Share Posted January 11, 2013 12z Euro looks much colder in the extended. Link to comment Share on other sites More sharing options...
WestMichigan Posted January 11, 2013 Share Posted January 11, 2013 I am liking the 12z Euro much better than what I have been lately. Link to comment Share on other sites More sharing options...
Ajdos Posted January 11, 2013 Share Posted January 11, 2013 Dry and Cold,, what a nice combo... Link to comment Share on other sites More sharing options...
SpartyOn Posted January 11, 2013 Share Posted January 11, 2013 Dry and Cold,, what a nice combo... Indeed. Going into a dry cold suppresed pattern in an already sucktastic winter. Link to comment Share on other sites More sharing options...
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