Mid January Discussion

[forkyfork]

Could see a streamer make it down to the coast later on Saturday.

it's part of a sfc trof

[SnowGoose69]

The 18z GFS at 300 hours shows another thing we need that we have not been getting this winter. Notice the high cuts across Canada, it does not dive SE across the OH Valley and merge with a Gulf high and then move offshore. We are getting that happening too much, even during the transient cold shots, the angle of departure of the high is important and we need them to stay north of us and exit to our north so that systems run into them and produce a NE flow and not S or SE.

[earthlight]

Regardless of these differences, there's no real blowtorch at least in the medium range

The GEFS means suggest that a good portion of the CONUS, especially east of the Plains, could experience 2m temperature departures of 8 degree or more above normal beginning around Day 10 and rolled forward, probably continuing through Day 15 at least.

This is supported by the retrograding Polar Vortex. The pattern definitely changed, as evidenced on all global ensembles with a tremendously anomalous ridge forming in the Pacific and moving northward. However, this ridge is too far west...and allows the Polar Vortex to retrograde and re-establish over Alaska, extending even to British Columbia Canada and as far west as the Aleutians. That is a very poor position for us. Because while there very well may be a gradient pattern to the east of it, there is nothing to keep us on the correct side of that gradient....like a -NAO for instance.

So the -EPO/AO regime definitely changed the pattern, but the lack of any high latitude blocking near the NAO region and the positioning of the two anomalous features in the Pacific...suggest that things could get very ugly to close out the month.

In fact, if the modeling is generally correct, I would not be surprised if the second half of the month featured the most anomalous positive 2m temperature departures we have seen so far this winter.

http://www.meteo.psu...NH_18z/f252.gif

http://www.meteo.psu...EP2_12z/D15.gif

[blizzardof09]

The GEFS means suggest that a good portion of the CONUS, especially east of the Plains, could experience 2m temperature departures of 8 degree or more above normal beginning around Day 10 and rolled forward, probably continuing through Day 15 at least.

This is supported by the retrograding Polar Vortex. The pattern definitely changed, as evidenced on all global ensembles with a tremendously anomalous ridge forming in the Pacific and moving northward. However, this ridge is too far west...and allows the Polar Vortex to retrograde and re-establish over Alaska, extending even to British Columbia Canada and as far west as the Aleutians. That is a very poor position for us. Because while there very well may be a gradient pattern to the east of it, there is nothing to keep us on the correct side of that gradient....like a -NAO for instance.

So the -EPO/AO regime definitely changed the pattern, but the lack of any high latitude blocking near the NAO region and the positioning of the two anomalous features in the Pacific...suggest that things could get very ugly to close out the month.

In fact, if the modeling is generally correct, I would not be surprised if the second half of the month featured the most anomalous positive 2m temperature departures we have seen so far this winter.

http://www.meteo.psu...NH_18z/f252.gif

http://www.meteo.psu...EP2_12z/D15.gif

so then what your saying is if taking that literally january as well as beginning of february may end up being a wash for us right?

[tmagan]

KFOK minimum on Monday may be in the low single digits.

[Ericjcrash]

KFOK minimum on Monday may be in the low single digits.

Obviously a blazing torch! Seriously with all the buds it will be an interesting spring with the freeze and thaw cycles.

[NYCSuburbs]

The GEFS means suggest that a good portion of the CONUS, especially east of the Plains, could experience 2m temperature departures of 8 degree or more above normal beginning around Day 10 and rolled forward, probably continuing through Day 15 at least.

This is supported by the retrograding Polar Vortex. The pattern definitely changed, as evidenced on all global ensembles with a tremendously anomalous ridge forming in the Pacific and moving northward. However, this ridge is too far west...and allows the Polar Vortex to retrograde and re-establish over Alaska, extending even to British Columbia Canada and as far west as the Aleutians. That is a very poor position for us. Because while there very well may be a gradient pattern to the east of it, there is nothing to keep us on the correct side of that gradient....like a -NAO for instance.

So the -EPO/AO regime definitely changed the pattern, but the lack of any high latitude blocking near the NAO region and the positioning of the two anomalous features in the Pacific...suggest that things could get very ugly to close out the month.

In fact, if the modeling is generally correct, I would not be surprised if the second half of the month featured the most anomalous positive 2m temperature departures we have seen so far this winter.

http://www.meteo.psu...NH_18z/f252.gif

http://www.meteo.psu...EP2_12z/D15.gif

I definitely agree with this analysis... I probably wasn't clear enough when I was trying to refer to the medium range as somewhere around the 6-10 day range, which is just my interpretation of the medium range, when there's still a bit of cold air around but no blowtorch at least in this region. Beyond Day 10, I certainly agree, the ridging is in a poor position with the gradient setting up too far to our north, and this time frame does have the potential to bring much warmer departures to a large part of the US, including NYC. With this type of pattern in place, I still don't see much reason to believe any of those pattern flip calls for the second half of the month, in fact as you said it could get even worse than it is now.

[bates]

The GEFS means suggest that a good portion of the CONUS, especially east of the Plains, could experience 2m temperature departures of 8 degree or more above normal beginning around Day 10 and rolled forward, probably continuing through Day 15 at least.

This is supported by the retrograding Polar Vortex. The pattern definitely changed, as evidenced on all global ensembles with a tremendously anomalous ridge forming in the Pacific and moving northward. However, this ridge is too far west...and allows the Polar Vortex to retrograde and re-establish over Alaska, extending even to British Columbia Canada and as far west as the Aleutians. That is a very poor position for us. Because while there very well may be a gradient pattern to the east of it, there is nothing to keep us on the correct side of that gradient....like a -NAO for instance.

So the -EPO/AO regime definitely changed the pattern, but the lack of any high latitude blocking near the NAO region and the positioning of the two anomalous features in the Pacific...suggest that things could get very ugly to close out the month.

In fact, if the modeling is generally correct, I would not be surprised if the second half of the month featured the most anomalous positive 2m temperature departures we have seen so far this winter.

http://www.meteo.psu...NH_18z/f252.gif

http://www.meteo.psu...EP2_12z/D15.gif

Really? Rather than the pattern definitely changing, it may be more precise and accurate that the pattern simply relaxed before re-loading and continuing.

[dbc]

The GEFS means suggest that a good portion of the CONUS, especially east of the Plains, could experience 2m temperature departures of 8 degree or more above normal beginning around Day 10 and rolled forward, probably continuing through Day 15 at least.

This is supported by the retrograding Polar Vortex. The pattern definitely changed, as evidenced on all global ensembles with a tremendously anomalous ridge forming in the Pacific and moving northward. However, this ridge is too far west...and allows the Polar Vortex to retrograde and re-establish over Alaska, extending even to British Columbia Canada and as far west as the Aleutians. That is a very poor position for us. Because while there very well may be a gradient pattern to the east of it, there is nothing to keep us on the correct side of that gradient....like a -NAO for instance.

So the -EPO/AO regime definitely changed the pattern, but the lack of any high latitude blocking near the NAO region and the positioning of the two anomalous features in the Pacific...suggest that things could get very ugly to close out the month.

In fact, if the modeling is generally correct, I would not be surprised if the second half of the month featured the most anomalous positive 2m temperature departures we have seen so far this winter.

http://www.meteo.psu...NH_18z/f252.gif

http://www.meteo.psu...EP2_12z/D15.gif

As always your analysis is spot on, but I must say at this range hardly a slam dunk. Some days ago we were seeing a reversal of this dreadful pattern to something more favorable for us at similar time ranges and obviously that has not verified now that the time frame prognosticated has arrived or will arrive in the coming days. So forgive me I do not buy this playing out exactly as depicted at the present time. Coud it? Sure but any of these long term model depictions changes on a whim from day to day.

[Nikolai]

Is noone else seeing snow?! Flurries in Harlem!

[ag3]

Is noone else seeing snow?! Flurries in Harlem!

Yup. All morning. Check the banter thread.

[earthlight]

Really? Rather than the pattern definitely changing, it may be more precise and accurate that the pattern simply relaxed before re-loading and continuing.

No, that would be incorrect. The pattern changed dramatically over a good part of the globe. To say that it relaxed and then continued the way it was before would be incorrect. The end result may not have been very "favorable" for our forecast area, or especially areas south of us, but the dramatic shifts in the pattern are noticeable and they are not forecast to reverse back to the way they were in December or very early January.

Here's a link to the current 500mb height anomalies (or yesterdays at 18z)

http://www.meteo.psu.edu/~gadomski/ENSHGTAVGNH_18z/f0.gif

And the forecast height anomalies rolled forward to almost 200 hours are below. You can see a complete reversal in the EPO and PNA regimes in the Pacific, and a re-orientation and re-positioning of the Polar Vortex. That is a pattern change.

[bluewave]

Nice little snow squall in progress along the South Shore right now.

It looks like we are getting some ocean enhancement.

[ag3]

Another burst of snow in Bayside with strong winds. Looks to continue on and off for the next hour or 2.

[HeatMiser]

it does seem as though models are starting to acknowledge blocking near greenland now in the outer frames. The weeklies finally acknowledged it as well. Hypothetically, if we actually see a -NAO lock in, what is the usual trend 30-45 days? I gotta think if it actually materializes, our odds for better cold shots get better.

[earthlight]

As always your analysis is spot on, but I must say at this range hardly a slam dunk. Some days ago we were seeing a reversal of this dreadful pattern to something more favorable for us at similar time ranges and obviously that has not verified now that the time frame prognosticated has arrived or will arrive in the coming days. So forgive me I do not buy this playing out exactly as depicted at the present time. Coud it? Sure but any of these long term model depictions changes on a whim from day to day.

Sure, but that is the nature of long term forecasting. The forecast models are tools to use as guidance moving forward, hence why I used the term "if it plays out as depicted".

Given the highly anomalous nature of the features being depicted on all global ensembles, I think it is fair to say that this point that a large trough/ area of -30dm or greater height departures will develop over the far Northeast Pacific, extending towards the Northwest US, British Columbia, and Alaska by around Day 10. The polar vortex is forecast to generally re-establish itself westward from the Davis Straight to Central Canada (brief window for something wintry when it's here) and then even farther west into West-Central Canada. Without any high latitude blocking over the North Atlantic or Greenland, this pattern out west and over the Pacific will give the Southeast Ridge plenty of room to amplify.

The NAEFS Week 2+ temperatures are in general agreement with most of the 2m temperature departures on the model ensembles...so I can't say I disagree with them at this time.

[NYCSuburbs]

To add to the mid-long range torch signals listed above:

500mb height anomalies - 0z ECM hour 240:

12z GFS and ECM 500mb height anomalies - hours 168-240

Note that the 0z version of this map was colder and did not have the SE ridge shown now, although this is mostly due to the fact that the warm period is starting to enter the 6-10 day range.

It's not a complete blowtorch for the entire time for everyone, but looking at the overall set up idea, there are clear signs that most of the strong cold air will stay trapped in Canada along with a ridge likely building near the central/eastern US, which is when we could see our torch.

[ag3]

The 12z Euro ensembles unfortunately match the operational; if not worse.

[earthlight]

The Euro is ugly. It re establishes the PV over Greenland along with a large negative height anomaly over Alaska and Western Canada. Probably one of the worst runs in the long range that I have seen so far this winter. This is probably one of the worst patterns you could see for snow on the East Coast.

http://www.meteo.psu...0.5_0z/f216.gif

http://www.meteo.psu.edu/~gadomski/ECMWF_0z/test8.gif

The GEFS are in good agreement with a 2m temperature positive anomaly response by Day 7-10 and rolled forward through Day 15. The initial data suggests next Thursday and Friday could be warmest -- with the GEFS means forecasting +15 to +18 2m temperature anomalies on Friday.

Moving forward, the guidance has some hints of changes in the N Atlantic. There were some weakly supportive signs on the Euro weeklies moving forward for a better setup in the N Atlantic and Greenland, but at this point nothing to write home about.

Start Tebowing.

[Weathergun]

The NCEP ensemble overnight had 850mb temps 10-12C above normal over us next Sunday. That would support temps at least upper 50s to around 60. Which would be around 20 degrees above normal:

Also looks almost as mild on Jan 26th:

[NYCSuburbs]

The NCEP ensemble overnight had 850mb temps 10-12C above normal over us next Sunday. That would support temps at least upper 50s to around 60. Which would be around 20 degrees above normal:

Also looks almost as mild on Jan 26th:

We've already had a 60+ degree day this month, although that one was unexpected and was limited to I-95 up to NYC. If the overall idea of the set up is right for the medium range and the SE ridge builds again, it's very possible that NYC would see another 50-55+ degree day, maybe even 60+ degrees for a day or two IMO if the torch gets close to its full potential. Apparently, even in an already terrible pattern, there's still room for the pattern to become worse...

[Isotherm]

The Euro is ugly. It re establishes the PV over Greenland along with a large negative height anomaly over Alaska and Western Canada. Probably one of the worst runs in the long range that I have seen so far this winter. This is probably one of the worst patterns you could see for snow on the East Coast.

http://www.meteo.psu...0.5_0z/f216.gif

http://www.meteo.psu...WF_0z/test8.gif

The GEFS are in good agreement with a 2m temperature positive anomaly response by Day 7-10 and rolled forward through Day 15. The initial data suggests next Thursday and Friday could be warmest -- with the GEFS means forecasting +15 to +18 2m temperature anomalies on Friday.

Moving forward, the guidance has some hints of changes in the N Atlantic. There were some weakly supportive signs on the Euro weeklies moving forward for a better setup in the N Atlantic and Greenland, but at this point nothing to write home about.

Start Tebowing.

Agree, models seem to have found a fairly tight consensus on this. January looks to be shot save for maybe a chance at snow before we torch.

[earthlight]

Lets see if we can get that lake effect streamer to make it near the coast. The SPC WRF says it will get here around 20-22z.

[earthlight]

Some very light returns showing up on KDIX radar over Western NJ along I-78. Trying to push east--although I'm not sure how much of that is reaching the ground.

[Ericjcrash]

Some very light returns showing up on KDIX radar over Western NJ along I-78. Trying to push east--although I'm not sure how much of that is reaching the ground.

DP's are relatively low, doubt any is reaching the ground.

[JCsnow17]

DP's are relatively low, doubt any is reaching the ground.

Actually have a few flurries now. Radar returns are light however.

[Ericjcrash]

Actually have a few flurries now. Radar returns are light however.

Flurries don't cut it, lol.

[JCsnow17]

Flurries don't cut it, lol.

This winter they do.

[ag3]

There are stray flurries around here.

[earthlight]

I guess there is a very small window for something around the 19th-20th of the month. There is a northern stream shortwave modeled to dive southeastward. The flow is fast, so it would have to amplify on it's own, but the potential might be there for some light snows anyway. Maybe something more if we can pull off a miracle and have the shortwave amplify enough to get a surface low going off the coast. The DGEX is close, and some of the GEFS members since 00z last night have shown rapid development off the coast as well. I suppose it's something to keep an eye on.