TROPICAL WEATHER UPDATE September 16th, 2010.

 Good morning everyone and welcome to my blog for THURSDAY September 16th, 2010. The tropics continue to be very active this morning, while both Igor and Julia have become less organized (particularly the latter) Karl is starting to become a dangerous cyclone to me, and I will start off with him first. Karl is currently located at 19.7°N 92.2°W, maximum sustained winds have increased to 65 mph (55 knots) and further strengthening is anticipated today, and I expect Karl will obtain hurricane status by tonight. Indeed, the current NHC/USAF Recon inside of TS Karl supports an intensity at 11 am of 70 mph and a pressure of 984 mb.

(current satellite image of TROPICAL STORM KARL)

Given the current rate of intensification, I full expect Karl to become a Category 2 hurricane, perhaps even a Category 3, before making landfall in Mexico. Karl has been meandering south of forecast points, and has been moving very slow too. The Bay of Campeche's topography is very favorable for cyclones to ramp up (adds to the cyclone circulation) as we saw with Hermine and Alex earlier this year. What concerns me is where Karl is heading, in a similar location to where Hurricane STAN of 2005 made landfall as a Category 1 hurricane. That killed 1,000+ people, and was retired due to the extensive amount of death it caused. Point being, Karl's main threats will be rain, as it will be a slow moving tropical cyclone once it makes landfall even if Karl doesn't obtain Category 3 status.

Hurricane Igor maintains strength

Hurricane Igor is currently located at 20.5°N 56.8°W. Maximum sustain winds have once again increased to 145 mph, but I believe Igor peaked the other day when it hit 155 mph. There is a possibility, given the fact the SAB and ADT both had Igor as a Category 5 hurricane that Igor will be upgraded to a 160 mph Category 5 hurricane once its Tropical Cyclone report comes out. Looking at Satellite, Igor has likely ingested some dry, stable air and has caused the core to become a little ragged looking, but the recent Eye-Wall replacement cycle has caused Igor to become much larger, and is now as large as the Gulf of Mexico.

Bermuda needs to be concerned about the possibility that Igor will be a Category 3 storm once it passes over them and preparations for that need to be made now. After it passes near Bermuda Igor should begin a extra-tropical transition and eventually become a powerful extra-tropical low in the northern Atlantic.

Julia unwinding

Julia is still a hurricane -- but only just. Currently located at 21.2 N, 36.1W. Maximum sustained winds have decreased to 105 mph thanks to the shear its big brother, Hurricane Igor, has brought over it. There is also some dry air getting into the core. I am trulely amazed though how yesterday morning Julia managed to become a Category 4 hurricane, and for a few hours for the first time in over 80 years we had 2 simultaneous Category 4 hurricanes out in the Atlantic! Wow! Julia also broke another record, the strongest hurricane ever recorded so far East, past 35W, and has broken Hurricane Fred 2009's record. Julia should begin to unravel the next few days before it also becomes absorbed into extra-Tropical Igor once it passes over cooler SSTs.

What else is behind this trio of storms?

The ECMWF is showing another Igor like system behind Julia developing, and seeing as this is starting to become later in the season it  is possible that if this develops it will be our last Cape Verde hurricane of the year. Activity will shift towards the US, and the GFS has been persistently showing that a hurricane will strike the Tampa Bay region in early October. This is unlikely to happen, given how far this is out but it is starting to show what patterns will be in place as we enter late September and Early October.

CybrTed