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8PM-Anylisis of Current Conditions, New Forecsats, and New Intermediate Advisory

Now it is time for the analysis. What exactly is happening? Where is the heaviest rain? Where are the strongest winds? Where is Sandy located? All is answered below.

First, the all-important NHC update.
Winds 75mph
Pressure 950mb
Movement NE 15mph

This has changed only very slightly from at 5 and at 2. The movement has increased slightly and the pressure has loweres a hair to 950 flat. This is down 1 mb from 2PM. This is slight strenghening and we sould expect a more rapid deepening trand as the warm core system moves over the Gulf Stram packing 80 degrees+ SST’s. This will quickly add a core wind speed of 10mph give or take a little and increase to 80-85mph by Monday Morning as it passes.

Sandy has tropical storm force winds extending 1000 miles+ out from the center and hurricane force winds 230 miles+ out from the center. The wierd thing is though, that the tropical storm force winds extend out farther to the NE than SW and the hurricane force winds extend farther to the SW than the NE.

After the Gulf Stream, the system will move over cooler waters of 65-70 degrees and will begin the transition to a full cold core system. This cold core system will be more adept to caputring the baroclinic energy brought in by the trough.

This may seem a bit overwhelming at first but it is just some pretty simple stuff under-cover. The lower left hand box is the moisture in the high levels of the atmosphere (35,000 feet). The moisture from Sandy is clearly visible streaming northward. The dry air that has been pertruding into Sandy’s eastern side is also clearly visible to her S and SE. The main photo is the winds from this altitude. I drew a black line where the approximate jet stream location is. The purple letters are “H” for ridge and “L” for upper level low/trough. Sandy is the ULL off the east coast and the centeral US trough is also shown.

This trough will inject a considerable amout of energy into the system and help to deepen it to a formidible 945mb low or lower just prior to landfall Monday evening. This will easily smash the records of 960, 955mb that have stood for centuries.

The winds between 5000 and 10000 feet will be absolutely howling as Sandy makes landfall as shown by this model plot.

As you can see, there will be winds in excess of 90 knots or 105mph.

This will be cause for major problems due to the convection firing on the western side of this storm will have the oppertunity to mix down down some of these winds to the surface creating quite a problem for the metropolis’. This is done by basically deflecting the winds like a light and a mirror by the downdraft pushing the winds down to the surface. Also, the high rises will be extra suseptable with winds increasing exponentially as you go up so that some of the tippy tops of the NYC sky-scrapers will be experiencing winds of CAT 5 intensity.

Surge is also another big thing to worry about as mentioned before. Surge heights go as following: South of Wilmington <2′, Wilmington to Cape Hatteras 2-6′, Cape Hatteras to VA beach, 3-6′, VA beach to Ocean City 4-7′, Ocean City to Montauk 4-8′, Long Island Sound 6-11′, NYC 11-15’+ Montauk to Boston 3-7′, Boston to Bath 2-5′, and North of Bath <2′

This is from this afternoon showing an 11′ water rise at the battery in Lower Manhattan which would flood out the subways.

NDBC Location: 31.862N 74.835W
Date:Sun, 28 Oct 2012 23:50:00 UTC
Winds: WNW (300°) at 36.9 kt gusting to 44.7 kt
Significant Wave Height: 23.0 ft
Dominant Wave Period: 11 sec
Mean Wave Direction: N (1°)
Atmospheric Pressure: 29.23 in and rising rapidly
Air Temperature: 72.3 F
Water Temperature: 77.4 F

Bouy data from SE of Cape Hatteras is shown above

Station 44065 NDBC Location: 40.369N 73.703W
Date:Sun, 28 Oct 2012 23:50:00 UTC
Winds: NE (40°) at 33.0 kt gusting to 38.9 kt
Significant Wave Height: 13.1 ft
Dominant Wave Period: 13 sec
Mean Wave Direction: SSE (152°)
Atmospheric Pressure: 29.61 in and falling
Air Temperature: 59.0 F
Dew Point: 53.2 F
Water Temperature: 60.6 F

Bouy data from New York Harbor is shown above

Station 44007 NDBC
43.531N 70.144W
Date:Sun, 28 Oct 2012 23:50:00 UTC
Winds: NNE (20°) at 17.5 kt gusting to 19.4 kt
Significant Wave Height: 4.9 ft
Dominant Wave Period: 8 sec
Atmospheric Pressure: 29.91 in and falling
Air Temperature: 51.3 F
Water Temperature: 53.8 F

Bouy data from just off of Portland ME is shown above

Station 44025 NDBC
Location: 40.250N 73.167W
Date:Sun, 28 Oct 2012 23:50:00 UTC
Winds: NE (40°) at 35.0 kt gusting to 42.7 kt
Significant Wave Height: 16.7 ft
Dominant Wave Period: 9 sec
Mean Wave Direction: ESE (107°)
Atmospheric Pressure: 29.57 in and falling
Air Temperature: 58.6 F
Dew Point: 55.9 F
Water Temperature: 61.3 F

Bouy data from off the Jersey Shore is shown above

Rainfall and inland flooding will be of great concern with rivers in VA already above flood stage prompting warnings. Amounts are as following: 10-12″ for NJ and easten PA as well as MD locally higher. 4-8″ For anywhere North of an Ocean City to Pittsburg line and South of a Pittsburg-NYC line. 1-2″ for areas north of Wilmington to Cleveland all the way over to Bangor Maine.

Satellite image of Sandy in the past few seconds courtesy of GOES 14 SRSOR (super rapid scan operational region)