**HURRICANE OPHELIA SLOWS RE-INTENSIFIES by Steve Gregory **

Sept 10, 2005 - 12:20PM CDT

OPHELIA -- A HURRICANE AGAIN -- MAJOR THREAT TO SOUTHEAST U.S.

After weakening to tropical storm overnight, due to dry air intrusion from the west, and southerly
wind shear, the storm has once again re-intensified into a Hurricane, and is slowing to a near crawl.

Air Force RECON indicated the central pressure has fallen significantly to 977mb, a 1-2mb/hr fall
over the last 7 hours, and the MAX sustained surface winds have increased to near 80 mph - in the
Northeast quadrant. The eyewall has again begun to reform, and is about 35NM across. The
'thermal eye wall' -- the temperature difference at 10,000 (700mb) between inside and outside
the eyewall is back up to 6degC -- very supportive of a solid CAT 1 Hurricane.

An unusual analysis of a data was disseminated by the latest RECON in which they did a Dropsonde
through several portions of the eyewall to ascertain the low level wind speeds.
One dropsonde reported 100kts at about 1,000 feet above the surface, and another found
the average boundary layer wind speed (surface to 1,000 ft over the ocean) of 82Kts,
or 88mph. The storm is still intensifying as evidenced by the latest VIS and IR imagery, with some
evidence that the eye is beginning to 'clear out'. This usually is not seen until a storm is of
Strong CAT 1 intensity.

The storm is located near 31.7N/76.3W - or 230 miles southeast of Charleston, SC and
215 miles SSW of Cape Hatteras, NC. The forward movement which had been averaging up
to 10Kts last night, has now slowed to only 4Kts, and the storm is essentially going stationary -- as
the models all predicted. A great example of how difficult it can be to 'go against' the models in
a general sense. While their accuracy is still nowhere as as good as we all would like them, and some
people think they are -- when there is a general consensus on the GENERAL track evolution of a storm,
it must be accepted as accurate.

A Hurricane Watch is now up from just north of Savannah, GA to Cape Lookout, N.C. The Watch
is usually issued when there is the threat of Hurricane conditions within the next 36hrs. This has
been done as a precautionary measure -- the actual forecast arrival of Ophelia on the coast is still
well over 72hrs away. However, the pressure gradient between the storm center and the High pressure
system to the north and west of the storm over the eastern U.S. is stronger than typical, and this had
led to a somewhat larger area of tropical storm force winds which as the storm approaches the coast,
will arrive much sooner than the hurricane itself. This includes very dangerous rip tide currents that
are already appearing on the Georgia to NC coast!

The models have all converged on the South Carolina to North Carolina coast as the area most likely to see
landfall in about 2-3 days. Those who have kept up with my updates will recall that the GFS called for a
landfall along the North and South Carolina border since the 00Z model runs 36 hours ago. -- right down the
middle of the various hurricane model consensus forecasts. A quick look at the very latest GFS forecast
shows a landfall TUES EVENING further north in NC near the Pamlico Sound area. This is on the northern
edge of the model consensus now, but as it really was the first model to forecast the looping motion and
eventual landfall on the coast some 5 days ago...I continue to have a preference for this model solution especially
when looking at forecasts beyond 48 hours that involve development on a global scale. ALL the other models use
the GFS or related global model, as their own initializations for the smaller scale, geographical boundaries that
they cover. If the GFS gets the the entire world pattern right, then theses specialize models will tend to get it right.
Since the out to sea and loop back scenario was highly dependant on the GFS global forecast showing the building
of a major high pressure system to the north and east of the storm -- and it was right -- I cannot help but put a lot
of faith in what this model is forecasting 3 days out.

The intensity forecast now becomes very problematic -- more than usual. On the one hand, a large area of
very dry air covers the southeastern U.S. and in fact helped to weaken the storm over night. However, with
the building sub-tropical ridge, the advance of this drier air towards the storm has halted, and over the next
2 days, will most likely only inhibit rapid intensification of the storm. I say most likely because intensity
forecasts have only slightly better skill scores than pure chance. For the moment, the specialized hurricane
forecast tools all point to a strong CAT 1 storm at landfall - and as such, that is the current forecast.
But it would not be out of the question to see a Strong CAT 2 storm either.

An update on this storm, with local observations and more details for residents along the Carolina's coast
will be sent this afternoon, with a full update on the storm this evening.

Steve

PIX 1 - Latest VIS image of Hurricane Ophelia shows the early stage of an visible eye formation,
and a return to the more classical 'circular' shape of a Hurricane. The effects of very dry air can
easily be seen over the far NW corner, where a more 'linear shaped' cutoff of the cloud field is noted.
The strongest feeder band extends from the northeast quadrant and then arcs Southeastward through
southwestward to near 28N/73W

PIX 2 - The 85Ghz microwave scan of the storm from several hours ago
now shows the best 'image signature' Ophelia has yet to to exhibit in the
past week., with the formation of intense convective cells completely surrounding
the center of the storm. Only the 'open eye' feature is not yet visible.

PIX 3 - Early 12Z model runs continue to show landfall somewhere along the Carolinas
coastline in 3+ days. Before Monday seems unlikely, while late Tuesday seem most likely.
The GFS as mentioned (not shown on this graphic) shows Pamlico Sound area Tues evening.

PIX 4 - All the model are sticking with a CAT 1 hurricane, but considering the latest observations,
this may turn out to be conservative. A LOT depends on where the storm positions itself relative
to the Gulf Stream. A slow moving system NOT over the Gulf Stream will upwell cooler sub-surface
water and that will greatly limit the intensity of the storm. If Ophelia manages to spend a fair amount
of time near or over the Gulf stream, greater intensification is possible. In addition, the close proximity
to extremely dry air over the SE U.S.may also result in limiting further storm intensification, or even
weaken it some before landfall. Simply too soon to tell.

PIX 5 - Latest Official Navy/NHC Track & Intensity forecast brings the storm to north of Charleston
Tuesday night as a CAT 1 Hurricane. But note the rather large area of gale force winds extending out
about 200NM from the center.