Monday, October 29, 2012

Hurricane Sandy

Statement as of 5:00 PM EDT on October 29, 2012

...Sandy moving quickly toward southern New Jersey and Delaware...
...Landfall expected early this evening accompanied by life-threatening storm surge and hurricane-force winds...

summary of 500 PM EDT...2100 UTC...information
location...38.8n 74.4w
about 30 mi...45 km ESE of Cape May New Jersey
about 40 mi...65 km S of Atlantic City New Jersey
maximum sustained winds...90 mph...150 km/h
present movement...WNW or 300 degrees at 28 mph...44 km/h
minimum central pressure...940 mb...27.76 inches

watches and warnings
changes with this advisory...

all tropical storm warnings for eastern North Carolina have been discontinued.

Summary of watches and warnings in effect...

there are no coastal tropical cyclone warnings in effect.

However...there are non-tropical high-wind warnings in effect for portions of the mid-Atlantic and New England states. Please see statements from local National Weather Service forecast offices.

 Hurricane-force winds are expected along portions of the coast between Chincoteague Virginia and Chatham Massachusetts. This includes the tidal Potomac from Cobb Island to Smith Point...the middle and upper Chesapeake Bay...Delaware Bay...and the coasts of the northern Delmarva Peninsula...New Jersey...the New York City area...Long Island...Connecticut...and Rhode Island.

Tropical-storm-force winds are expected north of Chatham to Merrimack River Massachusetts...the lower Chesapeake Bay...and south of Chincoteague to extreme northeastern North Carolina.

 For storm information specific to your area...including possible inland watches and warnings...please monitor products issued by your local National Weather Service forecast office.

 Discussion and 48-hour outlook
at 500 PM EDT...2100 UTC...the center of Hurricane Sandy was located by an Air Force Reserve hurricane hunter aircraft and NOAA Doppler weather radars to be near latitude 38.8 north...longitude 74.4 west. Sandy is moving toward the west-northwest near 28 mph...44 km/h. This general motion is expected to continue through this evening until landfall occurs. On the forecast track...the center of Sandy is expected to make landfall along or just south of the southern New Jersey coast within the next few hours.

 Maximum sustained winds are near 90 mph...150 km/h...with higher gusts.  Sandy is expected to transition into a frontal or wintertime low pressure system shortly. Little change in strength is expected prior to landfall. Sandy is forecast to weaken after landfall.

Hurricane-force winds extend outward up to 175 miles...280 km...from the center...and tropical-storm-force winds extend outward up to 485 miles...780 km. Sustained winds to tropical storm force are occurring from southern New England through Long Island and Long Island Sound...and southward along the coasts of New Jersey... Delaware...and eastern Virginia...and including all of the Chesapeake and Delaware bays. Hurricane-force wind gusts have been reported by ham radio operators across portions of extreme southeastern Massachusetts and Rhode Island. A ham radio operator recently reported a sustained wind of 64 mph...103 km/h...with gust to 86 mph...138 km/h in westerly Rhode Island...and another ham radio operator reported a wind gust to 76 mph...122 km/h in Barnstable Massachusetts.

The estimated minimum central pressure based on reports from the hurricane hunter aircraft is 940 mb/27.76 inches.

Hazards affecting land
wind...tropical-storm-force winds are already occurring over portions of the mid-Atlantic states from North Carolina northward to southern New England. Gale-force winds are expected to continue to spread over other portions of the mid-Atlantic states over the next couple of hours. Hurricane-force wind gusts have reached the southern Massachusetts and Rhode Island. Hurricane-force winds are expected to gradually spread across southern New England and mid-Atlantic states...from Connecticut southward to New Jersey and Delaware...including New York City and Long Island.

 It is important to note that winds affecting the upper floors of high-rise buildings will be significantly stronger than those near ground level.

Storm surge...the combination of an extremely dangerous storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters. The water could reach the following depths above ground if the peak surge occurs at the time of high tide...

 NC north of Surf City including Pamlico/Albemarle sounds...3 to 5 ft se VA and Delmarva including lower Chesapeake Bay...2 to 4 ft upper and middle Chesapeake Bay...1 to 3 ft Long Island Sound...Raritan Bay...and New York Harbor...6 to 11 ft elsewhere from Ocean City MD to the CT/RI border...4 to 8 ft CT/RI border to the South Shore of Cape Cod including Buzzards Bay and Narragansett Bay...3 to 6 ft Cape Cod to the MA/NH border including Cape Cod Bay...2 to 4 ft MA/NH border to the U.S./Canada border...1 to 3 ft

 surge-related flooding depends on the relative timing of the surge and the tidal cycle...and can vary greatly over short distances. Given the large wind field associated with Sandy...elevated water levels could span multiple tide cycles resulting in repeated and extended periods of coastal and Bayside flooding.  In addition... elevated waters could occur far removed from the center of Sandy. Furthermore...these conditions will occur regardless of whether Sandy is a tropical or Post-tropical cyclone.  For information specific to your area...please see products issued by your local National Weather Service office.

 Rainfall...rainfall totals of 3 to 6 inches are expected over far northeastern North Carolina with isolated maximum totals of 8 inches possible. Rainfall amounts of 4 to 8 inches are expected over portions of the mid Atlantic states...including the Delmarva Peninsula...with isolated maximum amounts of 12 inches possible.
Rainfall amounts of 1 to 3 inches with isolated maximum amounts of 5 inches are possible from the southern tier of New York state northeastward through New England.

 Snowfall..snow accumulations of 2 to 3 feet are expected in the mountains of West Virginia with locally higher totals today through Wednesday. Snowfall of 1 to 2 feet is expected in the mountains of southwestern Virginia to the Kentucky border...with 12 to 18 inches of snow expected in the mountains near the North Carolina/Tennessee border and in the mountains of western Maryland.

Surf...dangerous surf conditions will continue from Florida through New England for the next couple of days.

 Next advisory
next complete advisory...1100 PM EDT.
Tropical cyclone updates will be issued at 700 and 900 PM EDT...and
when landfall occurs.

Forecaster Stewart

1 comment:

NotClauswitz said...

The Hawspiper blogger has a remarkable perspective on the storm.