11 hours ago
Just posted this special edition of the trosum (tropical summary) on weather.com ...
Extraordinary storm, extremely serious threat
Stu Ostro, Senior Meteorologist, The Weather Channel
Oct 28, 2012 12:46 pm ET
- History is being written as an extreme weather event continues to unfold, one which will occupy a place in the annals of weather history as one of the most extraordinary to have affected the United States.
- REGARDLESS OF WHAT THE OFFICIAL DESIGNATION IS NOW OR AT/AFTER LANDFALL -- HURRICANE (INCLUDING IF "ONLY" A CATEGORY ONE), TROPICAL STORM, POST-TROPICAL, EXTRATROPICAL, WHATEVER -- OR WHAT TYPE OF WARNINGS ARE ISSUED BY THE NATIONAL WEATHER SERVICE AND NATIONAL HURRICANE CENTER -- PEOPLE IN THE PATH OF THIS STORM NEED TO HEED THE THREAT IT POSES WITH UTMOST URGENCY.
- TAKE COASTAL FLOODING EVACUATION ORDERS SERIOUSLY; PREPARE FOR DOWNED TREES AND STRUCTURAL DAMAGE BY OBSERVING TORNADO SAFETY GUIDELINES, I.E. STAYING INSIDE AND GETTING INTO THE LOWEST, MOST-INTERIOR PORTION OF THE BUILDING OR ANOTHER DESIGNATED SAFE PLACE; BE KEENLY AWARE OF YOUR LOCATION'S SUSCEPTIBILITY TO FLASH FLOODING (URBAN AND SMALL STREAM) FROM RAINFALL AND RIVER RISES; KNOW THAT YOU COULD BE WITHOUT POWER FOR A LONG TIME BUT ALSO UNDERSTAND THE DANGERS OF CARBON MONOXIDE POISONING FROM IMPROPER USE OF GENERATORS.
- With Sandy having already brought severe impacts to the Caribbean Islands and a portion of the Bahamas, and severe erosion to some beaches on the east coast of Florida, it is now poised to strike the northeast United States with a combination of track, size, structure and strength that is unprecedented in the known historical record there.
- Already, there are ominous signs: trees down in eastern North Carolina, the first of countless that will be blown over or uprooted along the storm's path; and coastal flooding in Florida, North Carolina and Virginia, these impacts occurring despite the center of circulation being so far offshore, an indication of Sandy's exceptional size and potency.
- A meteorologically mind-boggling combination of ingredients is coming together: one of the largest expanses of tropical storm (gale) force winds on record with a tropical or subtropical cyclone in the Atlantic or for that matter anywhere else in the world; a track of the center making a sharp left turn in direction of movement toward New Jersey in a way that is unprecedented in the historical database, as it gets blocked from moving out to sea by a pattern that includes an exceptionally strong ridge of high pressure aloft near Greenland; a "warm-core" tropical cyclone embedded within a larger, nor'easter-like circulation; and eventually tropical moisture and arctic air combining to produce heavy snow in interior high elevations. This is an extraordinary situation, and I am not prone to hyperbole.
- That gigantic size is a crucially important aspect of this storm. The massive breadth of its strong winds will produce a much wider scope of impacts than if it were a tiny system, and some of them will extend very far inland. A cyclone with the same maximum sustained velocities (borderline tropical storm / hurricane) but with a very small diameter of tropical storm / gale force winds would not present nearly the same level of threat or expected effects. Unfortunately, that's not the case. This one's size, threat, and expected impacts are immense.
- Those continue to be: very powerful, gusty winds with widespread tree damage and an extreme amount and duration of power outages; major coastal flooding from storm surge along with large battering waves on top of that and severe beach erosion; flooding from heavy rainfall; and heavy snow accumulations in the central Appalachians.
- Sandy is so large that there is even a tropical storm warning in effect in Bermuda, and the Bermuda Weather Service is forecasting wave heights outside the reef as high as 30'.
- There is a serious danger to mariners from a humongous area of high seas which in some areas will include waves of colossal height. Wave forecast models are predicting significant wave heights up to 50+ feet, and that is the average of the top 1/3, meaning that there will be individual waves that are even higher. The Perfect Storm, originally known as the Halloween Storm because of the time of year when it occurred, peaking in 1991 on the same dates (October 28-30) as Sandy, became a part of popular culture because of the tragedy at sea. This one has some of the same meteorological characteristics and ingredients coming together, but in an even more extreme way, and slamming more directly onshore and then much farther inland and thus having a far greater scope and variety of impacts.