I know that all attention for the next week is going to be on the East Coast and Irene’s eventual impact. I’ll do my best here to clear up any confusion or concern. I will start by saying that even with the shift in track in the models towards the NC/SC border, I still think it’s too early to lock onto this landfall idea. NHC keeps moving the track slowly east and I don’t see the harm in that. The morning model runs had a significant swing to the east with a couple of the models showing Irene missing the U.S. altogether. I know many would wish for this to happen, but I’m not buying it. . .yet. Over the course of the next few days, I will break down the pattern and how this will lead to the eventual impacts (or non-impacts) of Irene for the East Coast.
Above is the latest IR satellite image of Irene with a nice, strong convective burst showing up near or just to the north of the eye. An earlier radar image from San Juan shows the eye in the NW (far upper-left) corner of the radar range. After this image, the eyewall looks to have tightened, though the pressure remains around 988 mb and winds around 70 knots (80 mph). Irene should continue to strengthen over the next few days as it should not be hindered much by Hispaniola, though a minor plateau in strength should occur during the next 24 hours until the storm pulls further away from the island. This hinderance would be due to strong downsloping off the high mountains of the island, which acts to dry the atmosphere out. After this point, I see no reason why Irene would not intensify (possibly rapidly) into a Category 3 or 4 hurricane.
The 12z track guidance is focused on the northeast SC coast and looking quickly at the 18z guidance, the shift is more towards the Wilmington, NC area. I am leary on believing that right now, but regardless, both the SC and NC coasts look to receive quite a storm towards the weekend. The 12z intensity guidance shows decent agreement on a CAT 2 or 3 storm around landfall. Typically, the models underestimate the intensity, so I would be prepared for something stronger and hope for the best. In my opinion (and I was wrong on the westward track through the Caribbean, mind you) a landfall along the SC coast at CAT 3 strength would be my early forecast. Landfall is still a few days away and much can (and will) change. By the way, the reason my forecast ideas were wrong was because the center of Irene kept jumping north with the convective bursts. . .a further north position meant it was less likely to go through the Caribbean and therefore less likely to affect the Gulf coast. I’m sure many people are happy about this and even FL looks to escape the biggest impacts.
Update: I have included the NHC forecast track for Irene (above). Anyone reading this from FL on up to ME should be prepared for very heavy rainfall (especially near the center and just to the west) and strong winds (again, near the center, but more so to the east). This will be a big impact storm, especially for coastal areas. If the storm recurves out to sea, the effects further north will be diminished. My model of choice based on consistency is the European with a 969 mb hurricane (~115 mph winds) making a landfall in northeastern SC. This track would bring the worst conditions to the NC coast. I will update more on effects further north with time.
Elsewhere in the tropics. . .98L is still spinning in the middle of nowhere, Atlantic and will be a non-story for a few days. I do think it has a chance to become a tropical cyclone, but it has a hostile environment to overcome. Still, it has some fight to it. Another area of disturbed weather has moved off the African coast and a few models are developing this system in the next 5 days.
I mentioned a post or two ago about how hyperactive a start we have had to the 2011 hurricane season. To date, we are tied with 1936 for the earliest 9th storm of the season. 2005 is the only year that was ahead of us with Jose forming by August 22 and Katrina forming on the 23rd. With the possibility that Jose forms in the next 3-5 days, the system after that would be called Katia. I can’t make this stuff up. It’s kind of weird that we are using the 2005 list and we are on pace for 25+ storms. Amazing.
Stay tuned for updates and if you have any questions or concerns, please let me know.
Thanks for reading!