I will say that I am very suprised that the Hurricane Hunters did not find a closed surface circulation yesterday when they flew through 92L. Both the Air Force KC-130W and the NOAA high altitude jet was in the system yesterday at the same time, looking and searching. They found a well developed low pressure center that just had not made it to the surface yet. This morning, the satellite pictures show a developing system.

(Infrared Satellite - Image Courtesy: NOAA/CIRA)

The morning satellite pictures show a good looking, fairly symmetrical system with upper level outflow established to the north, east and south. A burst of heavy storms this morning was evident right over San Juan both on satellite and Puerto Rico radar images. Radar does show lots of heavy rain and indications of spiraling bands developing to the northeast of the island. The center of the mid level circulation appears to be just off the northern coast of the island with the heaviest storms displaced to the south of the center. There is lots of data to look at now with this system, all with just about any outcome you want so lets look at what we see as the most viable solution…

THE FORECAST PATH:

All the tropical forecast models continue to push the idea of a general north of west track over the next 50 hours or so.

(Tropical Forecast Models - Image Courtesy: Weather Underground)

As the storm continues to the west-northwest it should start it’s poleward turn in response to a mid-level trough of low pressure that is expected to be over the central U.S. at the first of next week. There is some debate on wheteher the trough will be strong enough to pull it off the coast at this point. As you can see from the model plots, this is a troubling path for the Bahamas, the Florida east coast as well as Georgia and South Carolina. There are too many varying model solutions out there now to make a definitive call, but we must watch this closely. If the system stay somewhat disorganized today, it may move more westward over the island of Hispanola, which would weaken the system. If it moves more over the open waters offshore, look for a growing system. With that being said, lets look at the intensity forecast.

HOW STRONG?

The look of 92L on the satellite already shows a system getting better and better organized by the hour. the upper level shear is low, less than 10 knots and it should stay that way over the next five days or so. An upper level anticyclone (high pressure) is building over the region and that will help vent the upper levels of the storm, making the upper level conditions about perfect for intensification. In the lower levels, as soon as the low level circulation can close off the growth should really begin. The storm is still surrounded by some drier air, but it is deep enough now that it has moistened the atmosphere enough that it should not feel any effects from the Saharan Air Layer.

(Tropical Intensity Forecast - Image Courtesy: Colorado State University)

The tropical intensity models all take the system just about directly to a tropical storm and then show a gradual increase to a Category 1 storm. As the system approaches the Bahamas toward the end of the weekend the SHIPS and GFDL both make it a Category 2 storm. With the warm water and low shear, it could be even stronger than forecast. Remember…there is much less accuracy in the fields of intensity forecasting so stay on top of the forecast day by day for the latest.

WHERE DOES IT GO?

Thats a question that I wish someone could answer for me! 92L is currently in a location that bears close watching as it could affect folks from the central Gulf Coast, around Florida to the coast of the Carolinas. My best guess this morning is that once the system can “officially” develop it continues west-northwest very near the northern coasts of the Dominican Republic and Cuba through Saturday. If the storm tracks over the islands, the high mountains could weaken or tear the system apart. If the center stays over water, look for a gradual increase in strength. The oceanic heat content in the water around the Bahamas is very high and this could lead to rapid intensification. There is a moderate chance of a strong Category 2 hurricane in the central Bahamas by the end of the weekend. Beyond that, it all depends on the upper level steering currents as to whether it stalls off the Florida coast, moves toward the Gulf of Mexico or makes a bee line toward the Carolinas. It must be noted that the GFDL has a Category 4 hurricane off the southern South Carolina coastline next Wednesday…just to reinforce the idea we have to be ready.
(GFDL Forecast - Click For Full Size Image - Image Courtesy: Florida State Univesity) 

The general consensus is that it’s a good time to keep tuned to the forecast. There may be no threat to us but the setup bears close watching…which we will do. Make sure that if you have a generator, it is working and you have all the necessary supples you need to protect your home if that becomes the case. Stay with us here on the Blog all weekend long as more and more data becomes available.

Chad Watson
Live 5 Meteorologist

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