donsutherland1 Posted January 13, 2017 Share Posted January 13, 2017 33 minutes ago, pazzo83 said: Bluewave, Isotherm, PB, Forky, Don, others? Do you think the profound lack of sea ice and unusually large areas of open water in the Arctic right now will have material impacts on the pattern going forward? If so, what do you think they'd be? With a large measure of caution, I believe this outcome might modestly increase/lengthen the persistence of the pattern that evolves. There seems to be some evidence of that in the winter and, more recently, a paper also suggested such an impact for the summer. http://science.sciencemag.org/content/early/2015/03/11/science.1261768.full There is still a lot of debate on this topic, but it seems that the evidence for such an effect is gradually increasing. Whether or not it has operational forecasting implications right now remains to be seen. Link to comment Share on other sites More sharing options...
danstorm Posted January 13, 2017 Share Posted January 13, 2017 38 minutes ago, pazzo83 said: Same downtown (KJRB - Wall St). Park at 46F - been pretty steady since this morning. Steady temp is indicative that there's cold air advection occurring, it's just being offset by the solar radiation. Link to comment Share on other sites More sharing options...
snywx Posted January 13, 2017 Share Posted January 13, 2017 Been stuck at 39° here for quite some time Link to comment Share on other sites More sharing options...
donsutherland1 Posted January 13, 2017 Share Posted January 13, 2017 Today’s extended range GFS ensembles closely resemble some past patterns that have developed given the forecast teleconnections (EPO, AO, and PNA). The 500 mb pattern shown below the GEFS forecast is based on a composite of 91 dates from teleconnections similar to those forecast in the extended range. The charts illustrate how that pattern evolved: 1. Discontinuous trough development took place in the East during the early stages of the pattern change 2. The trough became established in the East after 5-7 days 3. Seven to ten days afterward there was a significant pattern amplification That would essentially take us out toward mid-February. Following the pattern amplification, a number of scenarios would be plausible. The trough could migrate northward into Canada (with or without a ridge developing beneath it). The trough could migrate into the Deep South while weakening. All of that is far in the extended range. The main points are (1) there is growing guidance indicating the potential for a pattern change toward the end of January and, (2) the pattern change could bring potential in terms of cold and snowfall. It should be noted that the charts that follow provide an illustration for a “big picture” snapshot, only. The specific details remain to be worked out. Link to comment Share on other sites More sharing options...
Morris Posted January 13, 2017 Share Posted January 13, 2017 Link to comment Share on other sites More sharing options...
WeatherFeen2000 Posted January 13, 2017 Share Posted January 13, 2017 That looks juicy! Link to comment Share on other sites More sharing options...
SnowGoose69 Posted January 13, 2017 Share Posted January 13, 2017 5 minutes ago, Morris said: The Op run changes every run usually from Day 8 onward Link to comment Share on other sites More sharing options...
jm1220 Posted January 13, 2017 Share Posted January 13, 2017 20 minutes ago, Morris said: Wow, palm trees on Hudson Bay and icebergs in New Orleans anyone? Link to comment Share on other sites More sharing options...
SnowGoose69 Posted January 13, 2017 Share Posted January 13, 2017 5 minutes ago, jm1220 said: Wow, palm trees on Hudson Bay and icebergs in New Orleans anyone? When you look closer the cold air is very stale down there Link to comment Share on other sites More sharing options...
Isotherm Posted January 14, 2017 Share Posted January 14, 2017 EPS continues with the +NAM/NAO through late Jan, which isn't surprising that it backed off a bit once again. I personally think the pattern is quite hideous for east coast snowstorms through the 26th: the very end of the EPS could potentially be serviceable, for the interior particularly, but it is really a transitional period. The MJO forcing won't fully realize until early February, and then we'll have to monitor the stratosphere for polar cooperation. The million dollar question is: will this be a transient window or sustained pattern? If we revert back to Nina forcing as the MJO effect decays coupled with an unfavorable stratosphere, warmth will return. If we see some dominos line up, it will be a good pattern, and if the stratospheric vortex splits, it will be excellent. Right now I am favoring the improved pattern but nowhere near historic or ideal at this juncture. That can change, but I need to see more evidence over the coming days. Link to comment Share on other sites More sharing options...
bluewave Posted January 14, 2017 Share Posted January 14, 2017 LGA may have set a new record for January warmth combined with above normal snowfall. This may be the first time that January 1-13 went +4.8 with a 38.1 average temperature and 8.3" of snow. Average January snowfall at LGA is 7.4" with a 32.9 mean temperature. The last two times that LGA finished January with a similar snowfall total, it needed much more cold to get the job done. Jan 2009..-4.1...28.0....9.8" Jan 2001..+2.2..33.7...7.4" Link to comment Share on other sites More sharing options...
donsutherland1 Posted January 14, 2017 Share Posted January 14, 2017 Today, the PNA was +0.361, marking the first time since December 22 that it has been positive. As happened during the prior to the just-ended streak of PNA- days, the guidance suggests that the current PNA+ stretch will be short-lived (the previous one lasted 6 days from December 17 through December 22). During the prior PNA+ period, the MJO was in Phase 6. It is currently in Phase 6. However, this is where the similarities end going forward, at least if the guidance is correct. The December 17-22 PNA+ period was followed by an MJO that skipped Phases 7 and 1 and spent all of one day in Phase 2. This time around, it is forecast to spend considerable time and at higher amplitude moving through Phases 8, 1, 2, and 3. For the January-March period, those phases typically favor colder weather (the composite temperature anomalies are posted at the end of this message). However, before we reach the transition that should get underway during the last week of January, a very warm period lies ahead. It is possible that New York City may even see another 60° reading during that time. Link to comment Share on other sites More sharing options...
CPcantmeasuresnow Posted January 14, 2017 Share Posted January 14, 2017 Central Park and JFK now 3.7 degrees above normal for the month, LGA 4.8 above. I revise what I said yesterday and say this month will definitely be a plus 5 for temperatures at every Upton reporting location. Actually with the next two days near normal and the ten days afterward now looking to be 10-15 above normal we may be looking at a top 10 warmest January when all is said and done. That will probably depend on whether or not we get the hoped for pattern change before the month ends. Link to comment Share on other sites More sharing options...
Allsnow Posted January 14, 2017 Share Posted January 14, 2017 Link to comment Share on other sites More sharing options...
UlsterCountySnowZ Posted January 14, 2017 Share Posted January 14, 2017 Sitting at 25, got down to 16 last night Link to comment Share on other sites More sharing options...
Paragon Posted January 14, 2017 Share Posted January 14, 2017 5 hours ago, bluewave said: LGA may have set a new record for January warmth combined with above normal snowfall. This may be the first time that January 1-13 went +4.8 with a 38.1 average temperature and 8.3" of snow. Average January snowfall at LGA is 7.4" with a 32.9 mean temperature. The last two times that LGA finished January with a similar snowfall total, it needed much more cold to get the job done. Jan 2009..-4.1...28.0....9.8" Jan 2001..+2.2..33.7...7.4" Thanks, are the numbers looking similarly exceptional for JFK? Link to comment Share on other sites More sharing options...
bluewave Posted January 14, 2017 Share Posted January 14, 2017 17 minutes ago, Paragon said: JFK is also doing much better in the snowfall department for a January that has been this mild. JFK...36.7...+3.7..avg 32.7.......9.3"....avg 6.3" Last two Januaries with similar snowfall were much colder. Jan...2001...31.8...+0.6....8.2" Jan...2000..30.7...-0.5......8.5" Link to comment Share on other sites More sharing options...
Paragon Posted January 14, 2017 Share Posted January 14, 2017 39 minutes ago, bluewave said: JFK is also doing much better in the snowfall department for a January that has been this mild. JFK...36.7...+3.7..avg 32.7.......9.3"....avg 6.3" Last two Januaries with similar snowfall were much colder. Jan...2001...31.8...+0.6....8.2" Jan...2000..30.7...-0.5......8.5" Thanks. Was less January much warmer than normal at JFK too? I know the snowfall was over 30" last January and they had their first 40-40 winter Link to comment Share on other sites More sharing options...
bluewave Posted January 14, 2017 Share Posted January 14, 2017 20 minutes ago, Paragon said: Thanks. Was less January much warmer than normal at JFK too? I know the snowfall was over 30" last January and they had their first 40-40 winter Yeah, last January was the snowiest on record for JFK with 31.3". The average temperature still finished a little above normal 34.6...+1.9. But the previous above 20" Januaries were generally 3 to 5 degrees colder. 1996...23.0"....31.2...0.0 2011..22.1"....29.1..-2.7 1978...20.1....29.2...-2.2 Link to comment Share on other sites More sharing options...
Paragon Posted January 14, 2017 Share Posted January 14, 2017 It's going to be very difficult to predict a below normal snowfall winter, even if we have strong signals for above normal temperatures. It seems that even a small window for below normal temp or normal temps is enough to get us a significant event. Likely altered storm track with storms that previously would have been offshore coming up the coast. Link to comment Share on other sites More sharing options...
Isotherm Posted January 14, 2017 Share Posted January 14, 2017 I'm not impressed with the stratospheric progression through D 10-12 at least. Still no indication of baroclinicity / tilt; temperature rise is meager, and wave-1/2 grossly insufficient to induce the type of heat flux necessary as a prerequisite for an official warming event. However, as I've said heretofore, wave-1 amplitudes will probably continue to increase as we move into early February, and at this time, probabilities will be higher. On the very, very end of the D10 ECMWF stratosphere forecast, it's still far from a SSW/MMW signature to me. Extrapolating forward -- if the wave driving were to persist -- the official event would likely be another 10-12 days away. And of course, a SSW doesn't necessarily guarantee a blocky troposphere either, due to uncertainties regarding effective downward propagation. There will be a disruption sufficient to enable the development of tropospheric higher geopotential heights over the EPO/PNA domains and Canada, reflective of the strat progression. One possibility is that the MJO propagation can aid in slowing the North Atlantic jet temporarily w/ a transient -NAO period in the early part of February coincident with the PNA/EPO amelioration. Essentially, I still like the idea of the tropical forcing driven Pacific improvements, with potentially some ephemeral help from the Atlantic. But I am not thinking a SSW is on the way for at least 14-17 days. We will see what things look like in a few days. Want to see how the wave driving progresses. But right now it is insufficient to induce anything more than a temporary off pole displacement, then subsequent reconsolidation at the pole. I do expect the realization of stronger wave-1 in early Feb which is why I am not asserting that chances are zero -- it may occur in early Feb; but it is too early to say right now. Link to comment Share on other sites More sharing options...
UlsterCountySnowZ Posted January 14, 2017 Share Posted January 14, 2017 That weenie nor'easter on the long rang GFS Is trending east, close on 12zgfs Link to comment Share on other sites More sharing options...
bklnwx1 Posted January 14, 2017 Share Posted January 14, 2017 Very light snow in Sheepshead Bay, Brooklyn. Just a few flakes. Link to comment Share on other sites More sharing options...
bklnwx1 Posted January 14, 2017 Share Posted January 14, 2017 Steady light snow, VIS down to ~ 1mi Link to comment Share on other sites More sharing options...
Paragon Posted January 14, 2017 Share Posted January 14, 2017 Nice light snow, big flakes, temp 33F Link to comment Share on other sites More sharing options...
pazzo83 Posted January 14, 2017 Share Posted January 14, 2017 Mod snow in lower Manhattan. Love it. Link to comment Share on other sites More sharing options...
Paragon Posted January 14, 2017 Share Posted January 14, 2017 It's only sticking to grass, car tops, roof tops, etc. Nothing on the roads, barely anything on the driveways or sidewalks Link to comment Share on other sites More sharing options...
Paragon Posted January 14, 2017 Share Posted January 14, 2017 51 minutes ago, pazzo83 said: Mod snow in lower Manhattan. Love it. Visibility at the Park is a quarter of a mile, half a mile at the airports, everyone in the upper 20s now (28-29). Link to comment Share on other sites More sharing options...
PB GFI Posted January 14, 2017 Share Posted January 14, 2017 After todays event most stations from EWR on East will finish with a total of 10 to 15 inches already for the season Thats pre Jan 15 / not too shabby . After the warm up that ocurrs between the 17th and 24th we are going to enter into a favorable period from the 25th into most of February. So just maybe it wants to snow here this year.... I expect these totals to triple before winter is over . Link to comment Share on other sites More sharing options...
Isotherm Posted January 14, 2017 Share Posted January 14, 2017 +15, +25, +15 the past three days respectively at KNYC. +3.7 for the month there, and +4.8 at LGA. A top 10 warmest January possible. Link to comment Share on other sites More sharing options...
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