Sandy/Posttrop Phase Thread For PHL Area

[tombo82685]

What's the word on them?

the mean is just outside the bm, but it shows the operational is not the outlier with other members supporting or west of it.

[Yes_Probably_Maybe_No]

Could be a bad sign for winter with 7 day teases and then meh...it looks like to me that one of the early battles on the models will be if we can get some of that west based -NAO to slip on south and create some separation between our storm and the LP to it's NE.

Certainly would make trick or treating interesting...

[tombo82685]

Could be a bad sign for winter with 7 day teases and then meh...it looks like to me that one of the early battles on the models will be if we can get some of that west based -NAO to slip on south and create some separation between our storm and the LP to it's NE.

Certainly would make trick or treating interesting...

i think the low to the northeast is acting as a block, which is being blocked itself by the -nao.

[Yes_Probably_Maybe_No]

i think the low to the northeast is acting as a block, which is being blocked itself by the -nao.

The way I viewed it on the models, particularly the GFS and Euro (prior to hr 168), is that Sandy ends up following the path of least resistance and simply goes underneath the HP blocking and follows that low like a magnet. If we can get ridging in between and force Sandy more westward, then it has a better shot at getting picked up by the trough. To me that looks like one of the biggest differences between the easterly models and westerly models like the GGEM.

[tombo82685]

The way I viewed it on the models, particularly the GFS and Euro (prior to hr 168), is that Sandy ends up following the path of least resistance and simply goes underneath the HP blocking and follows that low like a magnet. If we can get ridging in between and force Sandy more westward, then it has a better shot at getting picked up by the trough. To me that looks like one of the biggest differences between the easterly models and westerly models like the GGEM.

to me it looks like the difference is the sharpness of the trof and the s/w that rounds the base of it. The gfs trof is flattened out and when that s/w rotates through the base of the trof it can't pick the storm up. While you look at the ggem the trof is sharper and the s/w coming around it phases in with the storm.

The first image is the gfs, the second is the ggem. I circled in yellow the differences.

[NorEaster27]

If you're looking at only the GFS/EC then yes. However most of the other models are showing a more westward solution with vast disagreement in the 12z GFS ensemble members as well.

http://www.wunderground.com/tropical/tracking/at201218_ensmodel.html

I wouldnt call that vast disagreement, the exact opposite actually remarkable agreement given its 7 days out.

[dryslotted]

Glenn blogging this evening on Sandy's potential...

http://www.nbcphilad...-175318961.html

Once upon a time there was a 3-year old in Mt. Airy who experienced one of the strongest storms in Philadelphia history. Its name was Hazel, and it produced the highest wind gust ever recorded here-94 mph. Hazel formed in the Caribbean and raced up the East Coast, hitting North Carolina in the morning and passing west of Philadelphia THE SAME EVENING.

I AM NOT SAYING THAT WE WILL HAVE “ANOTHER HAZEL”. DON’T QUOTE ME THAT WAY. BUT DOES THAT MEAN WE HAVE TO SHUT UP AND IGNORE THE MOST ACCURATE COMPUTER MODEL IN THE WORLD?

Now to the science (yes, the 3-year old was me)……

Question 1: Is Sandy in a favorable position for a) strengthening and moving north for many days. Answer: Yes. The central Caribbean, where Sandy has just formed, is THE most favored area for formation in October. And, many October/November storms track northward (many track northeastward as well).

Question 2: Is the current overall weather pattern favorable for a strengthening, northward tracking storm. Yes. Computer models virtually all agree on at least 3 days of this.

The European computer model has, in general, gone for an extreme East Coast solution 3 times in a row. It has the unofficial title of most accurate model in the world overall, and has had that for at least 20 years.

Question 3: Are there other computer models that have extreme solutions, even if they are not identical to the EURO? Yes (No one would expect identical solutions 5-8 days ahead of time!). The Canadian has also had consistently extreme solutions for the past 24 hours. It often has extreme solutions, so that’s not too surprising. But another model, the UKMET, also had extreme solutions (not nearly as extreme as the other 2, but pretty impressive). Even the Japanese model is “onboard”. Only the American model, the GFS, has a clear out-to-sea solution.

Question 4: Is the EURO solution representative of other “ensemble members” from the EURO. Yes. The EURO is run 51 times with slight differences in the current conditions. At NBC10, we get maps and data from these “ensembles” exclusively. We can’t show them to you, but I can tell you that many of the 50 other solutions are extreme AND close enough to the East Coast for major impacts.

Question 5: Do the folks at the National Weather Service in Wash, DC think an extreme East Coast solution is possible? Yes. Here’s their official 7-day forecast valid next Monday.

Question 6: Even if the track of this Hurricane/Hybrid/Nor’easter goes hundreds of miles offshore, will it still have a significant impact on the East Coast? Yes. As we say all the time, hurricanes are NOT a point, often covering hundreds of miles. And part hurricane/part Nor’easter storms are often even bigger. That means heavy rain, gusty winds, rip currents, and beach erosion could still happen with an offshore track.

CONCLUSION:

Although it’s nearly a week from now, there is enough evidence for a large, strong storm of some sort: Tropical, Nor’easter, or Hybrid (combination, of Tropical & Nor’easter) tracking off the East Coast. Of course, details are far from clear-cut. I’ll update the scenarios and odds as the week progresses.

[am19psu]

Great write up from Glenn

[wederwarrior]

Great write up from Glenn

indeed

[Mitchell Gaines]

http://www.wundergro...8_ensmodel.html

I wouldnt call that vast disagreement, the exact opposite actually remarkable agreement given its 7 days out.

I see you point vast was a poor word choice on my part. Graphic shows about of 1/4-1/3 of members closer to other models.

[Mitchell Gaines]

Glenn blogging this evening on Sandy's potential...

http://www.nbcphilad...-175318961.html

Once upon a time there was a 3-year old in Mt. Airy who experienced one of the strongest storms in Philadelphia history. Its name was Hazel, and it produced the highest wind gust ever recorded here-94 mph. Hazel formed in the Caribbean and raced up the East Coast, hitting North Carolina in the morning and passing west of Philadelphia THE SAME EVENING.

I AM NOT SAYING THAT WE WILL HAVE “ANOTHER HAZEL”. DON’T QUOTE ME THAT WAY. BUT DOES THAT MEAN WE HAVE TO SHUT UP AND IGNORE THE MOST ACCURATE COMPUTER MODEL IN THE WORLD?

Now to the science (yes, the 3-year old was me)……

Question 1: Is Sandy in a favorable position for a) strengthening and moving north for many days. Answer: Yes. The central Caribbean, where Sandy has just formed, is THE most favored area for formation in October. And, many October/November storms track northward (many track northeastward as well).

Question 2: Is the current overall weather pattern favorable for a strengthening, northward tracking storm. Yes. Computer models virtually all agree on at least 3 days of this.

The European computer model has, in general, gone for an extreme East Coast solution 3 times in a row. It has the unofficial title of most accurate model in the world overall, and has had that for at least 20 years.

Question 3: Are there other computer models that have extreme solutions, even if they are not identical to the EURO? Yes (No one would expect identical solutions 5-8 days ahead of time!). The Canadian has also had consistently extreme solutions for the past 24 hours. It often has extreme solutions, so that’s not too surprising. But another model, the UKMET, also had extreme solutions (not nearly as extreme as the other 2, but pretty impressive). Even the Japanese model is “onboard”. Only the American model, the GFS, has a clear out-to-sea solution.

Question 4: Is the EURO solution representative of other “ensemble members” from the EURO. Yes. The EURO is run 51 times with slight differences in the current conditions. At NBC10, we get maps and data from these “ensembles” exclusively. We can’t show them to you, but I can tell you that many of the 50 other solutions are extreme AND close enough to the East Coast for major impacts.

Question 5: Do the folks at the National Weather Service in Wash, DC think an extreme East Coast solution is possible? Yes. Here’s their official 7-day forecast valid next Monday.

Question 6: Even if the track of this Hurricane/Hybrid/Nor’easter goes hundreds of miles offshore, will it still have a significant impact on the East Coast? Yes. As we say all the time, hurricanes are NOT a point, often covering hundreds of miles. And part hurricane/part Nor’easter storms are often even bigger. That means heavy rain, gusty winds, rip currents, and beach erosion could still happen with an offshore track.

CONCLUSION:

Although it’s nearly a week from now, there is enough evidence for a large, strong storm of some sort: Tropical, Nor’easter, or Hybrid (combination, of Tropical & Nor’easter) tracking off the East Coast. Of course, details are far from clear-cut. I’ll update the scenarios and odds as the week progresses.

Thanks for posting this. Good Insight from NBC 10.

[NaoPos]

0z GFS

18z

Good signs from out west, but she never gets captured on this run. However, it's a step towards the euro.

[AlexD]

The trend is your friend,.lol.

Seriously, though.....lets see how things stand Wednesday-ish.....then it might be time to give this more serious consideration...

[phlwx]

Euro brings it back in over Long Island/SNE.

Canadian brings a 960 low near Sandy Hook. Has it down to 939 as its strongest.

[Allsnow]

Euro ens mean right into sne

[tombo82685]

the clown maps for the euro for snowfall actually has snow for for delco on west. with lanc county getting several inches. also combine that with 5-7 inches of rain over the region from the euro.

[Voyager]

So, general thoughts without the extreme play-by-play are that the models are still on to the idea of this threat being legitimate. At least as of the latest models?

[phlwx]

the clown maps for the euro for snowfall actually has snow for for delco on west. with lanc county getting several inches. also combine that with 5-7 inches of rain over the region from the euro.

mix or even coating accums in the city.

[phlwx]

So, general thoughts without the extreme play-by-play are that the models are still on to the idea of this threat being legitimate. At least as of the latest models?

Yes and the GFS is latching back onto the idea of "something" for New England.

[am19psu]

So, general thoughts without the extreme play-by-play are that the models are still on to the idea of this threat being legitimate. At least as of the latest models?

It's still an extreme solution. I still wouldn't go higher than 20-40% for impacts to the US (which given the implications, is still a very legit threat). Euro ops is just a smidge left of the mean and there a lot of members that stronger/left of the op. The GEFS EnKF has a 2-3 members that try to recapture a la the Euro and same with the op GEFS. There is just too much uncertainty at this time to make any sort of call, outside of effects are possible but not necessarily likely.

[NaoPos]

Man, the GFS is locked in.

At this point, I still don't know who's closer to being in the right.

[Rainshadow]

It's still an extreme solution. I still wouldn't go higher than 20-40% for impacts to the US (which given the implications, is still a very legit threat). Euro ops is just a smidge left of the mean and there a lot of members that stronger/left of the op. The GEFS EnKF has a 2-3 members that try to recapture a la the Euro and same with the op GEFS. There is just too much uncertainty at this time to make any sort of call, outside of effects are possible but not necessarily likely.

Yes, that day 7 ellipse is quite large.

[Voyager]

Yes and the GFS is latching back onto the idea of "something" for New England.

It's still an extreme solution. I still wouldn't go higher than 20-40% for impacts to the US (which given the implications, is still a very legit threat). Euro ops is just a smidge left of the mean and there a lot of members that stronger/left of the op. The GEFS EnKF has a 2-3 members that try to recapture a la the Euro and same with the op GEFS. There is just too much uncertainty at this time to make any sort of call, outside of effects are possible but not necessarily likely.

Thanks guys!

[am19psu]

Yes, that day 7 ellipse is quite large.

I wish these ellipses were available for the Euro ensemble. It would show a completely different picture.

[NaoPos]

Just stumbled upon this in the SNE thread.

[Quakertown needs snow]

Congrats mts!

Joe Bastardi ‏@BigJoeBastardi

ECMWF has 2-3 foot snow totals in mtns of pa on western side with this. GFS trends west thru 96 hrs, then handoff to wrong trog starts

[chubbs]

Two of 06z GFS members bring Sandy to MA coast.

[Rtd208]

Tell you what, if things play out like some of the models are showing things are going to get very interesting around here in the Sunday into Tuesday timeframe. The impacts from this storm could be huge.

[forkyfork]

Yes, that day 7 ellipse is quite large.

looks like the block is forcing either a NW curve scenario or a squash out to sea

[forkyfork]

I wish these ellipses were available for the Euro ensemble. It would show a completely different picture.

what do they look like in terms of spread?