Karl strengthens, hurricane watch issued for Bermuda

Both Karl and Lisa are still active, but Karl is taking the spotlight as it approaches Bermuda.  It is also on an intensification trend, and could become the season's fifth hurricane later today or tomorrow.

Satellite image of Tropical Storm Karl.  Bermuda is the magenta speck just north of the center of the image.

As of 11am EDT, Karl's maximum sustained winds were 60mph, and it had begun the turn to the north... moving north at 12 mph.  It will make its closest approach to Bermuda tonight, and Bermuda is under a tropical storm warning and a hurricane watch. I have long, updating radar loops available at http://andrew.rsmas.miami.edu/bmcnoldy/tropics/radar/

There are four aircraft monitoring this storm through the day and night: the NOAA P-3 and AF C-130 (they fly right into it to gather key data about the vortex), and the NOAA G-IV and NASA's unmanned GlobalHawk (they fly over and around it to gather environmental data).

Further east, Lisa is barely clinging to tropical storm status as it faces strong wind shear.  The satellite appearance tells the story: the low-level circulation is completely exposed, and the little thunderstorm activity that is still occurring is displaced far to the northeast. It is forecast to weaken to a tropical depression later today, and then dissipate completely sometime tomorrow.

Finally, another easterly wave just exited the African coast on the 22nd.  It doesn't look like much now, but global models have been bullish on developing this one in the deep tropics in 5-7 days and tracking it through the Caribbean.  More on this next week... the next name on the list is Matthew.

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