At least 41 deaths so far from Hurricane Sandy (and counting)
Thousands of homes damaged or destroyed in Cuba
New Jersey & New York/Long Island most likely targets in latest model runs
Monday Night & Tuesday most likely landfall scenarios
Huge storm Sandy may produce flooding rains and damaging winds 300 miles from the center
Major northeast “Billion Dollar Disaster” now likely to unfold Monday through Halloween
“Perfect Storm” #2? Sandy may be historic billion dollar “weather event”
There are a handful of days in my 30 year career as meteorologist where I’ve looked at the weather maps and simply can’t believe my eyes.
The day before the Halloween Mega Storm. Hurricane Andrew. The June 17, 2010 Minnesota tornado outbreak. The “Domebuster” snowstorm in December of 2010.
Today is one of those days.
All week I’ve been talking and blogging about the “potential” and “possible” scenarios for a devastating blow to the East Coast from Hurricane Sandy. All week I’ve been quietly hoping, even praying the forecast models will turn the storm harmlessly out to sea.
Now, just 48 hours before the likely effects from Sandy start pounding the shores of New Jersey and Long Island, it’s time to face the reality that a major devastating blow is likely.
Here’s the latest breakdown on what is shaping up to be an historic blow to the U.S. East Coast form Hurricane Sandy next week.
Already a killer Hurricane:
Hurricane Sandy is already a killer storm. Sandy has killed at least 41 people according to AP, and the number will likely rise this weekend. Thousands of homes are destroyed in Cuba, and Sandy (11 deaths) is the deadliest hurricane in Cuba since Category 5 Dennis killed 16 in 2005.
Frankenstorm: What makes Sandy a unique “Monster Storm?”
Sandy is shaping up to be a unique storm in several ways.
-The unique “blocking” jet stream pattern will favor Sandy’s track to get pulled back to the west…instead of getting shoved out to sea by strong westerlies as is usually the case with late October hurricanes.
Image Credit: Remik Ziemlinski, Climate Central.
-Sandy will ride the unusually warm waters of the Gulf Stream on her path toward the East Coast. This will keep moisture and energy flowing into Sandy from below, and maintain the possibility of rapid, unexpected intensification.
-As Sandy emerges from the tropics, she will interact with the “northern stream” of westerlies. This transition to “extra tropical” status will inject new energy from the mid-latitude jet stream into Sandy.
-This will allow Sandy to morph into a tropical-mid latitude “hybrid” storm upon impact…to grow in size, and potentially spread her damaging wind field over a larger area.
-Because of Sandy’s large size, tropical storm force winds with damaging near hurricane force gusts may extend up to 300 miles outward from the center of Sandy as she comes ashore. This will happen over the most populous area of the USA, where 60 million people will feel the storm’s effects.
The Track: East Coast landfall now likely, perhaps unavoidable
The latest spaghetti models and official NHC track for Sandy now point to a USA landfall sometime Monday night or Tuesday.
The highest probability or “cluster” (there’s a new term for this storm) for landfall now aims somewhere between the New Jersey Coast and Long Island. That puts New York City in a high probability zone for damaging effects from wind and storm surge from Sandy.
The exact landfall of Sandy will be critical for storm surge. If the center comes ashore west of New York City along the Jersey Coast, a huge wall of water will be moved into the mouth of the Hudson River as the storm plows ashore.
Because of Sandy’s large size, exact landfall may not be as critical when it comes to flooding rains or wind damage. Those effects will occur over a large area, regardless of exactly where the storm comes ashore.
NHC forecasts a Category 1 hurricane with 80 mph winds around the time of landfall.
Most of the models show some intensification with Sandy in the 24 hours before landfall. Forecasting intensity with hurricanes is the least accurate part of hurricane science. Track forecasts are much more accurate.
Unusually warm water underneath Sandy complicates intensity forecast even more. There is a chance that Sandy could “flare” in a rapid burst of intensification in the 24 hours before landfall.
Saturday: Sandy pulls north out of the Bahamas and runs parallel to the Carolina Coast. Sandy may encounter increased wind shear which may weaken her slightly, but may maintain near hurricane status over warm waters of the Gulf Stream.
Though the storm will be well offshore, large waves and gusty winds will rake the Carolina Coasts.
NHC position and intensity forecast at noon EDT Saturday:
24H 27/1800Z 29.7N 76.1W 55 KT 65 MPH
Sandy is likely to intensify in a more favorable shear environment over warm water Sunday as she makes a closer pass outside the Outer Banks of North Carolina.
The Outer Banks will see large waves, significant shoreline erosion and squalls with possible damaging wind gusts.
48H 28/1800Z 33.1N 72.6W 65 KT 75 MPH
Sandy will likely intensify a bit more as she makes the turn toward the northwest…and the East Coast Monday.
Landfall between Delaware/New Jersey and Long Island Monday night or Tuesday is the currently favored scenario by the bulk of models. That means damaging effects from Sandy are possible anywhere from Washington D.C. to New York and potentially Boston.
The official NHC track follows the European model most closely.
72H 29/1800Z 37.0N 71.5W 70 KT 80 MPH
Here are some of the major model scenarios:
Euro: Landfall Monday night along the New Jersey/Delaware border
NOGAPS: Landfall near New York City Tuesday AM.
GFS: Landfall near eastern Long Island Tuesday AM, then a westward loop around New York City the next 24 hours.
NAM: Landfall near eastern Long Island early Tuesday AM.
My eye favors a more northward landfall along the New Jersey Coast, and potentially closer to New York City Monday night or Tuesday AM.
Effects: The making of a “Billion Dollar Weather Disaster”
Sandy has the rare potential to be a billion, and perhaps multi billion dollar weather disaster.
In some ways, exactly where Sandy comes ashore is not important. In some ways it’s critical.
-If Sandy makes landfall along the Jersey Coast south of New York City, the “L-Shaped” shoreline will act as a funnel to shove elevated storm surge into New York City, and potentially breach floodwalls in Manhattan.
-Regardless of where Sandy comes ashore, the following effects will likely occur over the most densely populated “Megalopolis” in the USA.
This includes Washington D.C. Philly, New York City & suburbs & beyond.
-Wind gusts over 60 mph over a large area
-Widespread tree and power line damage over a huge multi-state area
-Widespread power outages – millions without power leading up to Halloween
-Widespread flooding rainfall totals of 5″ to 10″+ inches, with localized 16″ totals possible
-Severe flooding on rivers well inland, numerous bridge and roads washed out
-Thousands of homes damaged by wind and or flooding
Source: NOAA’s Hydrometeorological Preciction Center (HPC)
Storm surge & waves:
-Massive shoreline erosion from storm surge and waves of 6′ to 12′+
Add it all up and we’re looking at the real potential for a billion dollars in insured losses, and possibly an historic “multi-billion” dollar weather event.
The effects of Sandy could linger for weeks and months. Though most areas will have a week to recover, there could be some residual effects for the election on November 6th. Sandy may soon be affecting pre election polls.
What the hurricane experts are saying:
Two of my most trusted sources on all things hurricane are The Weather Channel’s Bryan Norcross and Weather Underground’s Jeff Masters. I have met them both and had the opportunity to chat them up about hurricanes in the past.
Here are some excerpts from their recent blogs which give some perspective on why Sandy is such an unusual and remarkable storm. (My italics added)
Bryan Norcross Weather Channel Hurricane Expert
This is a beyond-strange situation. It’s unprecedented and bizarre. Hurricanes almost always bend out to sea in October, although there have been some exceptions when storms went due north, but rarely. No October tropical systems in the record book have turned left into the northeast coast.
The strong evidence we have that a significant, maybe historic, storm is going to hit the east coast is that EVERY reliable computer forecast model now says it’s going to happen. The only way we can forecast the weather four or five days days from now is with the aid of these super-complex computer programs run on supercomputers. The two best, the European and the U.S. GFS (Global Forecast System) run by NOAA, are now in reasonable agreement that there IS going to be an extraordinarily unusual confluence of events that results in a massive storm.
The upper-air steering pattern that is part of the puzzle is not all that unheard of. It happens when the atmosphere gets blocked over the Atlantic and the flow over the U.S. doubles back on itself. Sometimes big winter storms are involved.
The freak part is that a hurricane happens to be in the right place in the world to get sucked into this doubled-back channel of air and pulled inland from the coast.
And the double-freak part is that the upper level wind, instead of weakening the storm and simply absorbing the moisture – which would be annoying enough – is merging with the tropical system to create a monstrous hybrid vortex. A combination of a hurricane and a nor’easter.
Jeff Masters Weather Underground & TWC
Wind shear is expected to remain a high 30 – 55 knots for the next four days, as Sandy interacts with a trough of low pressure to its west. The high shear should keep Sandy from intensifying the way most hurricanes do–by pulling heat energy out of the ocean. However, the trough approaching from the west will inject into Sandy what is called “baroclinic” energy–the energy one can derive from the atmosphere when warm and cold air masses lie in close proximity to each other. This transition will reduce the hurricane’s peak winds, but strong winds will spread out over a wider area of ocean. This will increase the total amount of wind energy of the storm, keeping the storm surge threat high. This large wind field will likely drive a storm surge of 3 – 6 feet on Monday and Tuesday to the right of where the center makes landfall, on the mid-Atlantic or New York coasts. These storm surge heights will be among the highest ever recorded along the affected coasts, and will have the potential to cause hundreds of millions of dollars in damage.
In addaition to Updraft, here are some good links to follow as Sandy appraches.
-Jeff Masters Wunderblog
-Bryan Norcross Facebook page
Stay tuned as forecasts for Hurricane Sandy evolve this weekend.