Good morning! The National Hurricane Center has just upgraded the chance of the remnants of Colin becoming a tropical cyclone again in the next 48 hours to medium (50%). An Air Force plane will investigate Colin later on today. At this time, the system is still feeling the effects of 25+ knots of westerly wind shear; this is pushing all of the thunderstorms well east of where we think the center of circulation is. That said, you can see on the satellite view of Colin that there is quite a bit of thunderstorm activity and all it will take is a weakening of the wind shear over the next day or so for this to return to tropical depression or even tropical storm status. As I showed you yesterday, you can see on the 5,000 foot vorticity map (spin) there is still quite a bit of mid level rotation with Colin north of Puerto Rico (brighter orange colors) and once the shear weakens, that spin should resume at the low levels as well.
Where will Colin go? The idea continues to be for Colin to track east of the United States, with one caveat. Notice that the low level steering currents are WNW/NW. As long as Colin remains a weak system, it will want to follow the low level steering currents which will take it west of the forecast model tracks (these tracks all carry Colin toward Bermuda this weekend). A stronger system will feel the effects of upper level steering which should becoming more northerly and northeasterly the next day or two as a trough of low pressure moves into the eastern United States. In any event, whether Colin ends up tracking west of the forecast models or not, it will remain well east of Florida and pose no threat to our area. That's not to say it won't impact our weather though; as it perhaps consolidates with another area of low pressure, an upper level low might form off the east coast later this weekend and that would possibly force some drier air into the area Sunday and Monday. We'll keep an eye on that.
The tropics, in general, are becoming much more active. We are beginning to enter an upward phase of the Madden-Julian Oscillation in the Atlantic and this favors rising air and more thunderstorms. The area south of about 20 degrees north latitude is ripe for tropical development (away from the central Atlantic where the area is very dry -- for now). A large tropical wave is located just east of the dry air in the Atlantic and stands a very good chance of becoming our next storm this season over the next few days. There are also several waves about to exit the west coast of Africa that all will need to be watched.
Brian
