ATL: SANDY - Remnants - Discussion

[monicaei]

Noob question. Can anyone explain, fairly simply, why the models show this turning into the coast as opposed to staying offshore and getting flung out to sea like one would normally expect?

[RVAHudson]

Noob question. Can anyone explain, fairly simply, why the models show this turning into the coast as opposed to staying offshore and getting flung out to sea like one would normally expect?

This isn't the usual steering deal. Usually we're used to see systems pushed west by building high pressure to the north.

This time, Sandy will be "pulled" westward by the flow around the negatively-tilted trough over the upper midwest, it's acting like a magnet.

Moreover, the Sandy will have a lot of energy injected into it from that weather system. That baroclinic forcing will make this much larger than a normal tropical system. Winds will be very strong well north of the center. Could be historic.

This isn't without precedent, this has happened a lot of times over the years. It just hasn't happened since the internet has been around, so this a new experience for a lot of weather people.

MW

[Portastorm]

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The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.


Per the photo posted a few posts ago, look at all that mid-level cu - not exactly a hurricane anymore, that's for sure...

I'm going to take a guess and say everything is going to turn out better up north than everyone is fearing...

Frank

Congratulations Frank! You may be the only person I know of who is downplaying this storm threat for the East Coast. Understand, of course, that your statement goes against what every nationally respected meteorologist and all of the National Weather Service offices from the Middle Atlantic coast on up through New England are saying.

I'm going to take a guess and say you're going to end up being horribly wrong with your guess.

[wxman57]

Should I be fine on my Monday, 10/29, 6:30 AM-4 PM flight from London to Newark? Anyone think there will be delays/cancellations by that point up there?

Need to get home and do as much prep as possible before it actually hits.

Winds will likely already be at/near tropical storm strength in Newark by 4pm Monday. High probability your flight will be cancelled.

[GoneBabyGone]

Should I be fine on my Monday, 10/29, 6:30 AM-4 PM flight from London to Newark? Anyone think there will be delays/cancellations by that point up there?

Need to get home and do as much prep as possible before it actually hits.

Winds will likely already be at/near tropical storm strength in Newark by 4pm Monday. High probability your flight will be cancelled.

Thanks. Trying to schmooze my way into a free flight change now. Ugh.

[capepoint]

Personal Forecast Disclaimer:
The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.


Per the photo posted a few posts ago, look at all that mid-level cu - not exactly a hurricane anymore, that's for sure...

I'm going to take a guess and say everything is going to turn out better up north than everyone is fearing...

Frank

Well, you are partly correct.....this is transforming into a cool-cored system, just as has been predicted for several days now. And it's too bad too, because a true hurricane would end-up making a much small damage swath that this thing has the potential to make......As far as the rest of your statement, I hope to God that you are right, but I have a bad feeling that you are wrong. While I sort-of doubt the apocalyptic doomsday scenario that many are hyping (too many years of unfulfilled hype starting to take it's toll on me?) i am afraid that this will end-up costing Billions of dollars and a few lives......As most folks from NC north already know, Nor'easters are usually worse than hurricanes.

Personal Forecast Disclaimer:
The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[crimi481]

The Ridging/ High pressure surrounding Sandy may really slow her down -changing landfall locations later
N.W. motion may continue longer than thought. Last few frames more west than NW (wobble)
Current front in Gulf area is slowing down (southern part of it) - hitting high pressure? (angle of front)

http://www.ssec.wisc.edu/data/geo/index ... thod=flash

Not an official opinion -see NHC forecasts

[FutureEM]

Can we expect a new eye feature to form (baroclinicly?) with Sandy like the ones we have seen in similar storms, like the 1991 Perfect Storm or the blizzard of 2006.

[KBBOCA]

I found this transcript of a Twitter media call with NHC officials posted in the comments to Dr. Jeff Masters lated post at Wunderground. Very interesting reading. Sorry, I haven't figured out how to link to comments at Wunderground, so I'll post it all here.

Live-tweeting Media call with @NHC_Atlantic branch chief James Franklin and NCEP director Louis Uccellini on #Sandy

James Franklin from @NHC_Atlantic first up. #Sandy is a cat1 hurricane, 80 mph, moving NNW out of Bahamas. Turn was expected.

Franklin: Another turn back toward the N, then NW, is expected once it gets past the NC coastline. Error grows at days 3-5 days. #Sandy

Franklin: Someone is going to get a significant surge event out of this, but it's still too soon to tell whom. #Sandy

Franklin: Someone is going to get a significant surge event out of this, but it's still too soon to tell whom. #Sandy

NCEP director Uccellini: One complication is transformation from tropical to extra-tropical. #Sandy may not remain tropical to landfall.

Uccellini: When and where this transformation takes place probably won't have a big effect on impacts, however. #Sandy

Uccellini: We're at the 90% level of certainty that #Sandy will make landfall somewhere. Size of storm will dictate big wind/surge impacts.

Uccellini: #Sandy will cause some snow across the Apps, ctrl WV, and further west into eastern OH and into SW PA as colder air moves in.

Uccellini: Strong winds likely to develop in the Ohio valley and across the Great Lakes, especially east due to the size of the storm.

Uccellini: Want to emphasize - still a range of solutions for #Sandy's track. Track will dictate surge, rain most. Significant surge likely.

Uccellini: Current forecast track points to significant effects and risk of flooding in DC, DE, eastern/central PA and NY.

Question: Can you explain the difference of rain/snow depending on track differences north vs south? What totals can we expect? #Sandy
Uccellini: WV will be the snow area regardless of track due to upper level pattern. #Sandy

Uccellini: 10" of rainfall likely along and east of the eventual track w/ max amount concentrated close. Shift N would include SE NY. #Sandy

Uccellini: Wind likely from Carolinas well into New England. Wind minimum in the Appalachian mtns. Breezy again N/W of #Sandy.

Franklin: 4 days out, it doesn't pay to get too specific about winds given track error & complicated T/ET evolution at landfall. #Sandy

Franklin: Several hundred miles wide area of TS-force winds likely around the track with hurricane force winds close to center. #Sandy

Question: How big will the surge be and how much damage will it do relative to #Irene? #Sandy
Franklin: No specific numbers yet, but numbers higher than #Irene for someone with #Sandy.
Franklin: Wind field & angle of attack with #Sandy means a "very, very, very large area" of surge north of the center. Bigger than

Question: Best sense for what NYC will expect? Franklin: Not 4 days out. Track error is average 200 miles. #Sandy

Franklin: If track shifts south, NYC gets low-mid TS winds. If track shifts north, NYC gets high-end TS-force. #Sandy

Uccellini: Same is true for rainfall. Shift in track north would move rainfall maximum north toward NYC. #Sandy

Question: Any sense on what kind of snowfall we could see? Uccellini: Over 1 foot in WV mtns. Chances for 2' increasing. #Sandy

Uccellini: Lighter amounts in lower elevations in OH, PA, etc. Potential 4-8" in SE/E OH. #Sandy



Question: Chance of impacts being greater inland like #Irene? Uccellini: Chances of 4-8" of rain incr. Slow mvt, topo will enhance.

Franklin: Diff between trop cyclone and ET: With tropical, need storms to bring fast winds down to surface. Very spotty high winds.

Franklin: In #Sandy's case, it's the large-scale pressure field driving winds. This will give us a large area with a uniform wind field.

Question: Can you quantify this in terms of history? Barometric pressure? Franklin: Intensification due to tropical processes ending. #Sandy
Uccellini: The way the two systems are merging are contributing to each other to enhance the process. #Sandy

Uccellini: #Sandy has the potential of "standing on its own with respect to minimum surface pressure%u2026 [size]%u2026 and rainfall."

Uccellini: With #Sandy, "we're dealing with categories we don't normally see."

Question: Why is #Sandy moving so slow? Uccellini: Blocking flow - upper level systems aren't moving W-to-E like normal.

Uccellini: "Extraordinary" blocking pattern is also going to contribute to the westward movement that will drive #Sandy toward the coast.

Question: What's causing this blocking? Uccellini: "I am sure this will be the cause of research%u2026" #Sandy

Question (from Max Mayfield!): If #Sandy becomes ET, who issues advisories? NHC or HPC? When will the handoff?

Franklin: Goal is continuity of service. TC/ETC conversion is not an on/off time. Gives flexibility to when the handoff happens. #Sandy

Franklin: Plan for #Sandy is for HPC to continue to issue public advisories "earlier than they normally do", possibly before landfall.

Franklin: @NHC_Atlantic will continue to "lead the internal NWS coordination"with HPC, OPC, etc. #Sandy

Question: Was it HPC who came up with "Frankenstorm"? Seems to have taken off. Is that how it will be referred to? #Sandy

Uccellini: Phrase came out of an HPC discussion. Storms normally get names after the event. During event, it will be #Sandy.

Franklin: When HPC takes over, advisories will be under header "Post-tropical cyclone #Sandy"

Question: Normal models (WRF, NAM, etc.) forecasting big differences than @NHC_Atlantic track. Why? Franklin: NHC rarely uses NAM. #Sandy

Franklin: Two best performers long-term with track and ET transition are GFS and ECMWF. "Head and shoulders" above others. #Sandy

Franklin: Regional models (HWRF, GFDL) not being used because structure of #Sandy not well-represented.

Franklin: Leaning toward the ECMWF in part due to the fact that it picked up on the westward turn sooner than GFS. Expect EC > GFS. #Sandy

Uccellini: When we have phasing as we will have with #Sandy, *all* models are challenged by these kinds of system mergers.

Question: Can you be specific about precip - 4-8" of rain, up to 2' of snow. Entirety of storm or just a couple of days? #Sandy
Uccellini: Precip numbers for the entire event of #Sandy but locally heavier amounts are possible.
Uccellini: Full moon is Sunday, highest tides usually 1-2 days after. Could be multiple tidal cycles with #Sandy.

Question: Have you ever seen anything like this? #Sandy
Uccellini: In some ways, this is similar to the "perfect storm", other ways different. '91 had colder air, #Sandy is stronger TC.

End of Media call.

[WeatherNewbie]

Noob question. Can anyone explain, fairly simply, why the models show this turning into the coast as opposed to staying offshore and getting flung out to sea like one would normally expect?

there is a long post from houstonia on page 73 that actually explains it very well. the trough normally runs along the coast, which causes storms to bounce off it. this time, it will be facing the coast, which will funnel the storm inwards.

[Blown Away]

How much closer will Sandy get to me, she took a left hook and is beelining towards me in little Hobe Sound!!
http://www.ssd.noaa.gov/PS/TROP/floater ... -long.html

[ozonepete]

Can we expect a new eye feature to form (baroclinicly?) with Sandy like the ones we have seen in similar storms, like the 1991 Perfect Storm or the blizzard of 2006.

It is quite possible. Those "eye-like features" are common in the most powerful hybrid storms. They are called warm air seclusions because warm air gets wrapped into the center by the complex way fronts are drawn into the system.

[GCANE]

High CAPE air is mixing into the core and beginning to see a flare.

http://www.ssd.noaa.gov/PS/TROP/floater ... -long.html

http://rammb.cira.colostate.edu/product ... 261255.jpg

http://www.spc.noaa.gov/exper/mesoanaly ... sector=18#

[ozonepete]

Personal Forecast Disclaimer:
The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.


Per the photo posted a few posts ago, look at all that mid-level cu - not exactly a hurricane anymore, that's for sure...

I'm going to take a guess and say everything is going to turn out better up north than everyone is fearing...

Frank

Congratulations Frank! You may be the only person I know of who is downplaying this storm threat for the East Coast. Understand, of course, that your statement goes against what every nationally respected meteorologist and all of the National Weather Service offices from the Middle Atlantic coast on up through New England are saying.

I'm going to take a guess and say you're going to end up being horribly wrong with your guess.

I agree with you, Portastorm.

Frank, I sincerely hope no one in the path of this storm is deciding to ignore it because of what you're saying. Now THAT would be tragic.

[chris_fit]

She definitely put on the brakes last 2 hours or so

[jlauderdal]

How much closer will Sandy get to me, she took a left hook and is beelining towards me in little Hobe Sound!!
http://www.ssd.noaa.gov/PS/TROP/floater ... -long.html

some of the modeling yesterday was picking up on this motion in the northern bahamas,,lets give it a a few more hours and even out the motion

[curtadams]

Well, you are partly correct.....this is transforming into a cool-cored system, just as has been predicted for several days now. .

It's transforming to an extratropical structure (fronts around a low with precipitation in a wedge), but it's still warm-core, and likely to remain so until landfall or thereabouts. The very high clouds NW of the center indicate there's still oceanic heat driving the system (partly) and the GFS predicts it will stay warm-core for the next several days. At this point, it's subtropical and it's a hurricane, and the fact that there's not a category for subtropical hurricanes shows what a strange beastie Sandy has become.

[WeatherLovingDoc]

The Ridging/ High pressure surrounding Sandy may really slow her down -changing landfall locations later
N.W. motion may continue longer than thought. Last few frames more west than NW (wobble)
Current front in Gulf area is slowing down (southern part of it) - hitting high pressure? (angle of front)

http://www.ssec.wisc.edu/data/geo/index ... thod=flash

Not an official opinion -see NHC forecasts

Nice observations (not official forecast) and picture. Total amateur, and I believe I followed your points.

NO OFFICIAL FORECAST-see NHC.

[crimi481]

The Ridging/ High pressure surrounding Sandy may really slow her down -changing landfall locations later
N.W. motion may continue longer than thought. Last few frames more west than NW (wobble)
Current front in Gulf area is slowing down (southern part of it) - hitting high pressure? (angle of front)

http://www.ssec.wisc.edu/data/geo/index ... thod=flash

Not an official opinion -see NHC forecasts

Nice observations (not official forecast) and picture. Total amateur, and I believe I followed your points.

Thanks Doc! I know nothing - but fun trying?

NO OFFICIAL FORECAST-see NHC.

[bamajammer4eva]

This may have been mentioned already but with this happening one week before Election day it will be interesting to see how the polls handle it with the possibility of power and communications being out in some of the larger cities of the NE US. May be some paper voting going on instead of electronic leading to delayed results?