By Eric Holthaus
Hurricane Sandy has emerged from the Caribbean and appears to be making a beeline for Greater New York.
This won't be your average, everyday New York City hurricane threat (if there even is such a thing) — as Sandy moves northward, it will be increasingly drawn toward and eventually merge with a snowstorm currently forming over the Great Lakes, creating a Frankenstein monster of weather badness.
The Hydrometeorological Prediction Center — the branch of the National Weather Service with primary responsibility for Sandy once it leaves the tropics — themselves have offered up the hashtag #frankenstorm for the impending storm, emphasizing the storm's hybrid nature and its likely landfall date just before Halloween.
Here at Weather Journal, we've been preparing for Sandy all week. On Monday morning, we first raised the spectre of a potential Halloween superstorm. Later on Monday, once Sandy was named, we discussed the political ramifications of a pre-election landfall in several East Coast swing states, namely North Carolina, Virginia, Ohio, and New Hampshire — all of which could be looking at lingering impacts up to and including Election Day. On Tuesday, as the possibly historic nature of the storm became more apparent, we noted there was an increasingly narrow chance for the storm to escape safely out to sea. And on Wednesday, we gave four main reasons for why significant impacts in the New York City area are now likely.
In my live interview on the Journal's News Hub program Thursday afternoon, I explained that it's important to remember that Sandy will be a much larger than a normal hurricane — not necessarily in terms of wind speed, but definitely in the geographic scale and duration of the wind and flooding potential.
Now, it seems that hurricane models are beginning to converge on a likely strike somewhere between Delaware and Long Island, with the most likely place for the hybrid storm's center to come ashore right now looking like the central New Jersey shore. The entire tri-state is within the National Hurricane Center's most recent five-day cone, with experts there agreeing that New Jersey is Sandy's likely final destination. But the storm will be so large by its landfall on Tuesday that significant impacts will extend outward for hundreds of miles from the center. In my opinion, the worst of Sandy's coastal impacts are now likely to occur somewhere near the Greater New York area.
Here's a look at what the tri-state can expect should Sandy stay on its current course:
1) Coastal storm surge
Should the Frankenstorm version of Sandy stay south of New York City as the National Hurricane Center predicts, several feet of wind-driven ocean water would be funneled into New York Harbor and up against area beaches, especially along the south shore of Long Island. This will likely be the storm's greatest impact both locally and as a whole, and the local National Weather Service office has gone as far as to say this could be nearly a worst case scenario for the city, depending on the exact location of landfall.
In a phone conversation Thursday, meteorologist Jeff Masters from Weather Underground said that he expects Sandy could flood parts of the New York City subway system if current forecasts hold.
A National Weather Service wave height projection shows waves in excess of 30 feet just offshore as Sandy approaches, which would generate massive beach erosion and increase the storms destructive coastal potential.
To top it off, Sandy is expected to make landfall during the full moon, which would add an additional foot or so of tidal influence to coastal flooding projections.
2) Inland river flooding
Rainfall totals are expected to reach eight to 10 inches across parts of the tri-state, which would challenge totals achieved during Hurricane Irene. Though it is still too early to say, it doesn't initially appear that flooding will be as severe, as current river flows are drier than average for this time of year.
However, due to Sandy's angle of attack, places like the Catskills will endure extremely heavy rainfall for two to three days, prompting concerns about a repeat of flash flooding to some extent — though likely not as severe as during Irene.
3) Wind
Hurricane force wind gusts may also occur locally, especially on ocean-facing beaches on Long Island. Of particular concern is the fact that most area trees are still in full leaf, which could increase the chances of extensive power outages as they will more easily catch the wind. Wind damage could also occur within New York City itself, although I don't anticipate winds to be stronger than the were during Irene. Winds will, however, last much longer. While Irene moved through the five boroughs in a matter of hours, Sandy will linger much longer, increasing the potential for damages to occur.
4) Possible heavy wet snow
Areas to the south of where Sandy makes landfall could receive several inches — even up to a foot or more — of heavy wet snow as extremely cold air is pulled southward by Sandy's strong circulation. In keeping with Sandy's current track, that cold air could cause significant accumulating flakes from the Washington, D.C. area northward through Central Pennsylvania and much of western New York State. As those in Connecticut remember from last year's Snowtober, heavy snow mixed with fully leafed trees are not a good mix if you want to keep your power on.
Overnight, Sandy went through a period of rapid intensification after it made landfall near Kingston, Jamaica and before its second landfall in Cuba. The central pressure of the storm dropped so quickly (35 millibars in 24 hours) that maximum wind speeds increased from Category 1 to nearly Category 3 within a span of only six or so hours. The storm has remained a Category 2 throughout Thursday and is now expected to retain hurricane strength nearly up until its landfall in the United States on Tuesday.
Comparisons of Sandy have been made to the 1991 "Perfect Storm", where a large nor'easter absorbed Hurricane Grace well offshore of New England. However, most of the worst impacts of that storm occurred well out to sea. Last year's Hurricane Irene and the Snowtober snowstorm — if blended together — may provide other analogues of Sandy, however Irene was weakening upon its landfall in Coney Island, and the impact of the Snowtober storm was not fully captured by weather models until only a day or two before it struck. Still — lower Manhattan narrowly escaped flooding in Irene, and parts of Connecticut were without power for weeks in Snowtober.
Most likely, Sandy will be in a class by itself — as most major weather events tend to be. The storm will linger for more than 36 hours over the East Coast, pushing copious amounts of seawater ashore, and could produce October snowfall as far south as North Carolina.
Weather Journal will be back this weekend with a forecast update, providing more detailed wind, flooding, rainfall and snowfall estimates across the tri-state.
Your Weather Journal weekend forecast roundup:
- WSJ Headquarters in Manhattan:High: Friday: 69, Saturday: 68, Sunday: 63Low: Friday: 56, Saturday: 54, Sunday: 53Weather: Sandy's impacts begin Sunday
Friday/Saturday/Sunday Highs for Greater New York:
- Brooklyn: 70/68/63
- Queens: 70/70/64
- Bronx: 72/71/64
- Staten Island: 67/66/62
- Poughkeepsie, N.Y.: 68/69/59
- Trenton, N.J.: 72/69/62
- Islip, Long Island: 67/66/63
- New Haven, Conn.: 67/66/63
Meteorologist Eric Holthaus contributes daily weather reports and analysis on Metropolis. For the latest on conditions in New York and elsewhere, follow his updates (@WSJweather) on Twitter.
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