By Eric Holthaus
Weather models are beginning to coalesce around an unlikely meteorological scenario: a hurricane blending with an inland snowstorm just in time for Halloween.
Before we get into that weather wonderland, Greater New York will enjoy pleasant afternoon temperatures in the low 70s for the rest of the week. For next week, however, it's starting to seem like not a question of if but where this giant "snor'eastercane" might strike.
Regardless of the exact landfall location on the East Coast, impacts will be felt from Florida to Maine. Nearly every single major weather model now shows the eventual "phasing," or capture, of Hurricane Sandy by an intense polar airmass. The two primary medium-range forecast centers for the National Weather Service agree. The European ECMWF, generally considered one of the best weather models in the world, has shown this scenario consistently for the last five days.
This consensus gives me enough confidence to increase to two-out-of-three odds that Greater New York experiences significant impacts from this storm. Here are a few reasons why I'm expecting nasty weather ahead in New York City:
Orientation: Sandy is coming nearly due northward and should at least brush much of the East Coast on its way towards Greater New York. Although the storm will likely hook inland once it makes landfall, the storm should spend a significant amount of time running parallel to the coast, much like Hurricane Irene did last year.
At last count, major models showed potential landfall locations anywhere from Virginia Beach to Maine, with a blend of these outlooks favoring a hit near New York City or Long Island.
In the Hurricane Center's most recent track released Wednesday, the New Jersey shore is within the five-day cone of uncertainty. The center also lists odds for sustained tropical storm conditions in Greater New York at about one-in-10, which I would expect to rise significantly in the coming days.
Should the storm make landfall north of New York City, coastal flooding would be minimized but several inches of snowfall could drop on the region. With leaves still on the trees in New York City and Long Island, tree damage and power outages would be increased. If the storm makes landfall south of the five boroughs, that would mean the city is in line for Sandy's worst effects: storm surge, wind and heavy rains.
Since model averages prefer a landfall solution near the tri-state region, there's really nowhere for the storm to go anymore that would spare us at least some type of impact.
Size: The latest assessments of Sandy's destructive potential rate the storm's wave and surge potential at a 3.4 on a six-point scale. One respected meteorologist has already called Sandy "a potential billion dollar storm for the Mid-Atlantic and New England".
Overall Pattern: An increasingly negative NAO pattern is forecasted to become much stronger than normal, which will bring a near halt to the normal west-to-east movement of storm systems across the U.S. That more than anything else will open the door for Sandy to be sucked back towards the East Coast.
In a nearly unprecedented step, the National Weather Service has ordered a nationwide doubling of weather balloon launches starting Thursday afternoon in an attempt to get a better handle on this unusual atmospheric setup. That should increase the accuracy of models going forward.
Full Moon: One additional facet to this forecast is the high tides happening Monday during the full moon. Up to one additional foot of coastal flooding could occur should the storm make landfall at high tide.
New weather data could shift Sandy's projected track back out to sea in the coming days — especially with five days still to go. But so much agreement so early on in the forecast cycle should argue against big forecast changes from here on out.
Thursday's Greater New York forecast roundup:
- WSJ Headquarters in Manhattan:
- Actual High: 65; High feels like: 67
- Actual Low: 55; Low feels like: 57
- Weather: Patchy clouds
- Brooklyn: 65/56
- Queens: 65/58
- Bronx: 65/55
- Staten Island: 62/56
- Poughkeepsie, N.Y.: 64/48
- Trenton, N.J.: 72/53
- Islip, Long Island: 63/52
- New Haven, Conn.: 61/47
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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