Aug 14, 2011

DAY 74

A very interesting Hurricane Season continues to unfold. Tropical Storm Franklin was classified this morning and has already been reduced to a depression, and Invest 94L has been upgraded to Tropical Depression #7. While our 2 African waves continue to struggle.

Franklin wasn't even a tropical storm for 24 hours. He is now listed as a tropical depression and is racing off into the north Atlantic.

Still no Gert out there, but we're real close. Invest 94L has now been designated Tropical Depression #7, and is forecast to become Tropical Storm Gert in the morning. The image below is of  TD #7 during the daylight. There is a very visible surface circulation to it. After the sun set, the thunderstorm activity began to stack itself over that circulation indicating that it is still strengthening. It is moving WNW at 10 mph and is expected to be at tropical storm strength when it brushes Bermuda late tomorrow night or Monday morning.

If Gert does form from this system, and it probably will, it is not forecast to become a hurricane. So that would leave us with the first 7 named storms to have come and gone with no hurricanes. That has actually never happened in the history of hurricane record keeping. With 7 named storms before August 15th, we are well ahead of average for storms but behind in hurricane production. In case your wondering, there has only been 2 hurricane seasons without any hurricanes at all. The 1907 and 1914 seasons were hurricane-less. It should be noted however that that was way before the use of satellites. Since we started naming our hurricanes in 1950, there's never been a season without a cane.

I'm not saying that's gonna happen this year, it's just interesting. But there must be a reason beyond coincidence that there has been no hurricanes yet. One big reason is the huge amount of dry air in the Atlantic. There has been a lot of subsiding or sinking air in the Atlantic for more that a month now. One explanation is the MJO or Madden-Julian Oscillation having been in a downward phase. The MJO is a climate phase the moves around the planet like a wave. It has been in a downward phase over the Atlantic, but is forecast to switch to an upward phase soon. This should remove some of that dry air and help tropical systems grow.

2 systems that are struggling to grow are 92L and 93L. 92 is doing a little bit better today. It's starting to look a tropical depression and has more circulation to it than it did yesterday. The Hurricane Center is giving it a 30% chance of becoming a tropical cyclone in the next 48 hours. One problem it might run into though is that it is catching up to Tropical Depression #7.

93L is actually looking worse today than it did yesterday. NHC is giving it a near 0% chance of becoming a tropical cyclone in the next 48 hours. Just because this system looks pathetic right now, don't make the mistake of thinking that it is going to dissipate. We have seen many systems in the deep Atlantic struggle and even be deactivated, only to come back when it reaches the Caribbean. Which is still where 93L is forecast to go. This will likely remain an open wave until it reaches a more favorable environment.

No comments:

Post a Comment