If past experience with late-season tropical systems is of any relevance, it is unlikely that the Atlantic Ocean storm will back all the way into New England later this week.
Overall, since 1851, there have been 37 tropical systems that were heading west while east of 68° West and reached at least 65° West. 7 of those storms were late-season (formed October 1 or later) storms.
From these storms, three clusters can be found:
• Storms that failed to reach 70° West: Tropical Storm #8 (1943), Hurricane Karen (2001), and Tropical Storm Nicole (2004)
• Storms that moved reached 70° West but failed to make landfall: Hurricane Lili (1990), and Hurricane #8 (1991)
• Storms that turned south or southwest and then back more toward the west and came well west of 70° West. Some of these storms ultimately made landfall: Tropical Storm #9 (1906), Hurricane #6 (1935), and Tropical Storm #6 (1938)
In my view, this set of data strongly suggests that it would be unlikely for the Atlantic Ocean storm to track west all the way into New England. Rather, it would be more likely either to advance to point before heading eastward or turn south and southwestward before threatening the Southeast. However, given the presence of a southern stream system, I believe that the latter option is not very likely.
The threat of offshore phasing is a possibility. The former solution where the storm advances to a point before turning back seems to be the more reasonable idea, especially as the NAO- could be relaxing before strengthening again (per GFS ensembles). Consequently, there could be room for the southern stream system to take a less suppressed track than is currently implied by some of the modeling.
This does not mean that New England or even the northern Mid-Atlantic region cannot be impacted by the offshore storm. I would not be surprised if some of its precipitation does come ashore.
Finally, several caveats are in order:
1) The data set is limited.
2) This is just one set of scenarios per past tropical data. It is anything but all-inclusive.
This Week's Ocean Storm: Can Tropical Experience Shed Light?
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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.
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donsutherland1
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donsutherland1
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donsutherland1
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Re: This Week's Ocean Storm: Can Tropical Experience Shed Li
Last night, I drew upon past late-season tropical systems to see if this information could help shed light on a very complex situation for later this week.
Briefly, I found three distinct sets of storms:
• Storms that failed to reach 70° West: Tropical Storm #8 (1943), Hurricane Karen (2001), and Tropical Storm Nicole (2004)
• Storms that reached 70° West but failed to make landfall: Hurricane Lili (1990), and Hurricane #8 (1991)
• Storms that turned south or southwest and then back more toward the west and came well west of 70° West. Some of these storms ultimately made landfall: Tropical Storm #9 (1906), Hurricane #6 (1935), and Tropical Storm #6 (1938)
Taking into consideration the current level of blocking and the idea that it will be temporarily relaxing per the GFS ensembles, I believe one can begin to sketch one low probability scenario out of a number of such low probability scenarios that might have at least some merit in the face of a continuing lack of modeling consensus.
Under such a scenario, the Atlantic Ocean storm would continue to back westward. However, I do not believe there is sufficient blocking to drive it into the East Coast. So, the top two scenarios with an emphasis on the first (where the storm does not reach 70° W) might have relevance.
If one examines the latest PNA data, the PNA has gone negative. Thus, there might be a growing progressive emphasis downstream thought it should be reasonably mild at this time. This adds to the argument that the Ocean storm won't make landfall.
The return of the PNA- (which I expect to be transient) also suggests that the second system will probably exit the Coast either in the Southeast or lower Mid-Atlantic and, by itself, won't be turned northward.
By the time the second system is exiting, there is just a chance that the Ocean storm might try to begin to turn more toward the south as its forward motion toward the west slows.
Ultimately, this raises the question as to phasing. The way I see it, there is a chance that the Ocean storm absorbs the second storm. But this will only occur if the Ocean storm does, in fact, turn more toward the south to bring it in closer proximity.
If a phase takes place, it will probably be somewhere well off the Mid-Atlantic coast. In my view, it would be too far offshore to bring substantial precipitation to most of the Mid-Atlantic or Northeast.
More likely is that the storms do not come close enough to phase in the aforementioned vicinity. The second storm heads well offshore and then gradually turns more to the north--too far offshore again and follows the Ocean storm. Both gradually turn more toward the north and then perhaps bend a little to the west up around the Canadian Maritimes.
At that latter point, they pump the heights around Greenland and the NAO heads more negative (as has generally been depicted on the GFS ensembles for some time).
Impacts:
• Coastal New England/Coastal Mid-Atlantic: Period of mixed precipitation/rain and wind. Beach erosion.
• Interior Northeast/Interior Mid-Atlantic and I-95 Cities: Possible mixed precipitation/rain but not significant. Breezy.
• Lower Mid-Atlantic/Southeast: Rain from exiting system; NC Mountains and usual CAD-effected areas; Snow to ice to mixed precipitation.
Briefly, I found three distinct sets of storms:
• Storms that failed to reach 70° West: Tropical Storm #8 (1943), Hurricane Karen (2001), and Tropical Storm Nicole (2004)
• Storms that reached 70° West but failed to make landfall: Hurricane Lili (1990), and Hurricane #8 (1991)
• Storms that turned south or southwest and then back more toward the west and came well west of 70° West. Some of these storms ultimately made landfall: Tropical Storm #9 (1906), Hurricane #6 (1935), and Tropical Storm #6 (1938)
Taking into consideration the current level of blocking and the idea that it will be temporarily relaxing per the GFS ensembles, I believe one can begin to sketch one low probability scenario out of a number of such low probability scenarios that might have at least some merit in the face of a continuing lack of modeling consensus.
Under such a scenario, the Atlantic Ocean storm would continue to back westward. However, I do not believe there is sufficient blocking to drive it into the East Coast. So, the top two scenarios with an emphasis on the first (where the storm does not reach 70° W) might have relevance.
If one examines the latest PNA data, the PNA has gone negative. Thus, there might be a growing progressive emphasis downstream thought it should be reasonably mild at this time. This adds to the argument that the Ocean storm won't make landfall.
The return of the PNA- (which I expect to be transient) also suggests that the second system will probably exit the Coast either in the Southeast or lower Mid-Atlantic and, by itself, won't be turned northward.
By the time the second system is exiting, there is just a chance that the Ocean storm might try to begin to turn more toward the south as its forward motion toward the west slows.
Ultimately, this raises the question as to phasing. The way I see it, there is a chance that the Ocean storm absorbs the second storm. But this will only occur if the Ocean storm does, in fact, turn more toward the south to bring it in closer proximity.
If a phase takes place, it will probably be somewhere well off the Mid-Atlantic coast. In my view, it would be too far offshore to bring substantial precipitation to most of the Mid-Atlantic or Northeast.
More likely is that the storms do not come close enough to phase in the aforementioned vicinity. The second storm heads well offshore and then gradually turns more to the north--too far offshore again and follows the Ocean storm. Both gradually turn more toward the north and then perhaps bend a little to the west up around the Canadian Maritimes.
At that latter point, they pump the heights around Greenland and the NAO heads more negative (as has generally been depicted on the GFS ensembles for some time).
Impacts:
• Coastal New England/Coastal Mid-Atlantic: Period of mixed precipitation/rain and wind. Beach erosion.
• Interior Northeast/Interior Mid-Atlantic and I-95 Cities: Possible mixed precipitation/rain but not significant. Breezy.
• Lower Mid-Atlantic/Southeast: Rain from exiting system; NC Mountains and usual CAD-effected areas; Snow to ice to mixed precipitation.
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donsutherland1
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Re: This Week's Ocean Storm: Can Tropical Experience Shed Li
For those who are interested, in his midday discussion, JB has laid out a scenario of a system that tracks southwestward, south, and then exits southeast. However, rather than the Ocean storm taking such a track, he envisions a separate system developing south of Nantucket taking such a course.
Overall, this should prove to be a fascinating situation however it unfolds. If it materializes as JB suggested, it showed that an examination of late-season tropical events had at least partial relevance e.g., the southwest and south turn of a system (even if it doesn't then turn more to the west afterward).
What ultimately happens remains uncertain, but at this time, I'm somewhat comfortable with the impacts I described earlier. I should add that JB's sketch could have somewhat more wintry implications than my initial ideas for parts of the affected region.
Overall, this should prove to be a fascinating situation however it unfolds. If it materializes as JB suggested, it showed that an examination of late-season tropical events had at least partial relevance e.g., the southwest and south turn of a system (even if it doesn't then turn more to the west afterward).
What ultimately happens remains uncertain, but at this time, I'm somewhat comfortable with the impacts I described earlier. I should add that JB's sketch could have somewhat more wintry implications than my initial ideas for parts of the affected region.
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donsutherland1
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Stephanie,
It would certainly be an intense storm. I don't believe it would bomb to the extent of the "Perfect Storm" as that unnamed Hurricane tapped into enormous warmth from the dying Hurricane Grace. Still, it would be a formidable storm. However, its main effects would be felt on the coastline--beach erosion, coastal flooding, perhaps some heavy precipitation--and by shipping interests. I don't believe it would be close enough to bring a damaging event to the major cities of the Mid-Atlantic/Northeast.
It would certainly be an intense storm. I don't believe it would bomb to the extent of the "Perfect Storm" as that unnamed Hurricane tapped into enormous warmth from the dying Hurricane Grace. Still, it would be a formidable storm. However, its main effects would be felt on the coastline--beach erosion, coastal flooding, perhaps some heavy precipitation--and by shipping interests. I don't believe it would be close enough to bring a damaging event to the major cities of the Mid-Atlantic/Northeast.
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