So here we are with Tropical Storm Irene at approximately 64 West and there still hasn't been a hurricane hunter reconnaissance plane go out to measure real time data from inside and around Irene. This is surprising and creating quite a problem when it comes to trying to track where Irene is going to go in approximately 5-7 days. Hurricane models base their forecast on data entered into their various algorithms. The more accurate the data; the better the models. The models for Irene have been all over the map. Well this is no surprise since the data going into the models has been speculative and based on satellite imagery. Irene has had some pretty complex weather patterns surrounding it on its trip across the Atlantic, making the forecast very difficult. Guessing on where the center is and how strong pressure and mid-level winds are around the storm, make accurate forecasting almost impossible. The moral of the story is that it is hard to believe any of the forecast for Irene at this point, since we really have no accurate data to put into the models. Hurricane Hunter aircraft is now scheduled to fly into Irene on Friday afternoon, which will help considerably.
Now on to the forecast scenario for Irene. Irene has clearly been gaining strength again today, but still is not an extremely well organized system. Dry air at the mid-levels have been coming in from the SE, disrupting convection and sucking moisture out of the southern portion of the storm. This dry air is forecast to weaken tomorrow and the path will then be open for Irene to gain strength over the extremely warm waters of the East Coast.
Irene will also have high pressure building in on the north side of the storm. Since Irene rotates counter-clockwise and the high pressure rotates clockwise, they will be helping each other. This is the scenario that was in place with Hurricane Andrew. A strong high pressure ridge to the north of Andrew help the storm gain significant strength in a very short period of time. Some forecasters believe this is possible with Irene. It won't be a Cat 5 like Andrew, but could grow into a major hurricane very quickly. The high pressure ridge will also be trying to push Irene to the west, how far west really depends on how far that ridge builds in.
The NHC is forecasting Irene to make a turn towards the NW and North off the Carolina coast. Other forecasters believe Irene will make landfall between Cape Lookout and Cape Hatteras, then move up the Sound into SE Virginia (ala Isabel 2003). The only thing we are really sure of is that Irene is going to be putting on a show the next 5 days and we will all be watching very closely. Prepare for an onslaught of local news coverage, long lines at Home Depot and a run on milk and bread at the stores. It is August in the Carolinas after all and that's what we do.
*Note - This post is not done by a professional Meteorologist and should not be used for making decisions on safety and protection of property. Always use your local National Weather Service station or the National Hurricane Center for up to date weather information and data.*