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Hurricane fatigue:

It's all-Wilma-all-the-time on the news channels but the bottom line is that Wilma is picking up strength and speed as it heads towards Florida. Storm surge is a real concern. Here's Jeff Master's take on his blog at Weather Underground:

Wilma has entered a slow intensification phase the past three hours. The pressure has fallen from 963 mb to 959 mb, the eye has shrunk in diameter from 60 nm to 45 nm, and satellite imagery shows cooling cloud tops in the eyewall region--all signs of an ongoing intensification cycle. In response to this intensification cycle, the Hurricane Center has now upped their forecast of the maximum storm surge from 13 feet to 17 feet over southwest Florida. At the current rate of intensification, Wilma could become a Category 3 hurricane with 115 mph winds by midnight.

This intensification phase should slow down or reverse by midnight, since shear is now increasing over the storm. Shear is now about 15 knots, up from 10 knots this morning. The hurricane hunters noted that strong westerly winds aloft have pushed the top of the storm eastward, so that the area of calm in the eye at 10,000 feet is about ten miles east of the surface calm area. This stretching is also beginning to be evident on satellite images, with the shape of the hurricane appearing less circular. Assuming that the shear begins weakening the hurricane at midnight, only six or eight hours remain for the shear to weaken the hurricane before landfall at 6 am or 8 am Monday morning.

There's been quite a bit of focus on Key West but the storm should hit well north, just over Marco Island (where I was relaxing on the beach about a week ago.)

There are a couple of Marco webcams (updated every minute) that might be interesting to check tomorrow if the power doesn't cut out: Looking north from the south end of the beach and looking out over the resident's beach. Both are situated high on condo towers along the beach. There's also a live cam at the Snook Inn that sweeps around the Marco River.

Most of Marco is only about ten feet above sea level and the storm surge could be ten feet or more. If the storm hits to the north of Marco the surge would be worse; south, not as bad. High tide tomorrow at about 6 AM will, unfortunately, coincide with the storm's landfall. Click the extended entry for more on the surge potential.

Brian Woods at Storm Track notes an interesting situation as Wilma and Alpha merge off the east coast of Florida and head north, possibly combining into a Cat 2 storm off Cape Cod Tuesday.

More on the storm surge potential in SW Florida:

[C]oastlines such as those along Florida's Gulf coast and the Florida Keys have long, gently sloping shelves and shallow water depths. The 180 meter (600-foot) depth contour followed southward from Palm Beach County lies more than 30 km to the east of the upper Keys. On the Gulf side of Florida, the edge of the Floridian Plateau (91 meter depth) lies more than 160 km offshore of Marco Island in Collier County. Florida Bay, lying between the Florida Keys and the mainland, is very shallow; depths typically vary between 0.3 and 2 meters (Lane, 1981). These areas are subject to higher storm surge, but smaller waves. Palm trees in Islamorada The Florida Keys is an archipelago or cluster of about 1700 islands in the extreme southeast of the United States. ... Collier County is a county located in the U.S. state of Florida. ... Florida Bay is the shallow bay located between the southern end of the Florida mainland (the Florida Everglades) and the Florida Keys. ...

This difference is because in deeper water, a surge can be dispersed down and away from the hurricane. However, upon entering the shallow, gently sloping shelf, the surge can not be dispersed away, but is driven ashore by the wind stresses of the hurricane. Topography of the land surface is an important element in storm surge extent. Areas such as those seen in southern Florida where the land lies less than a few meters above sea level are at particular risk from storm surge inundation.
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