Tropics showing signs of activity and of possible impacts in coming days

Area of disturbed weather in the Caribbean Sea that has potential for development over the coming days

Area of disturbed weather in the Caribbean Sea that has potential for development over the coming days

Just as we are about to end September, which was as quiet as you will likely ever see it, things begin to become more active across the Atlantic.

Here is a run down of what’s going on and where…

In the central Atlantic, a tropical wave that had been tangled up with an upper level low pressure area has become better organized today. The NHC says it could become a tropical depression over the next day or so as it remains well out to sea and away from any land areas. It could eventually become a weak tropical storm but it should not last too long considering the fairly hostile environment over the Atlantic right now.

The other area to watch, which is of greater concern right now, is in the Caribbean Sea. An area of showers and thunderstorms has developed in association with a large pressure fall in the region. Several of the global models go on to develop this system as it moves northwest and eventually in to the southeast Gulf of Mexico.

Ocean heat content is still quite high across the Caribbean Sea and in to parts of the SE Gulf of Mexico

Ocean heat content is still quite high across the Caribbean Sea and in to parts of the SE Gulf of Mexico

While none of the guidance shows anything very strong at the moment, one must keep in mind that the water is very warm in this area and will be along much of the track of this potential system. The mitigating factor seems to be upper level winds which do not appear to be very conducive for significant strengthening over the coming days. Nevertheless, rain and squally weather is likely to spread across portions of the Caribbean Sea and eventually impact Jamaica and Cuba before reaching the southeast Gulf of Mexico.

Beyond that time, we will just have to see what we’re dealing with in terms of storm structure, upper level winds and steering flow. Speculating about potential impacts to Florida beyond the five day time period is pointless right now except to say that folks along the west coast should be keeping an eye on this feature – just as you would any October tropical development. With the recent heavy rains for parts of the state, a tropical cyclone of any intensity would not be good news. We’ll see how things play out over the next few days and whether or not we actually have a tropical depression or storm develop from this system.

Elsewhere, the eastern Atlantic looks to try and spin up another weak storm as the pattern tries to make up for lost ground in recent weeks. There are some indications that the MJO or Madden-Julian Oscillation, which promotes tropical convection and upward motion, could become more favorable across the Atlantic Basin in the coming weeks. This could result in a very busy October, especially considering the warm water temps that are in abundance right now. It is important to at least pay attention to the tropics as the old saying goes about it not being over until it’s over…

I’ll have more here tomorrow, sooner if something develops and warrants an additional post.

M. Sudduth 2:10 pm ET Sept 28

Tropics look busy but it’s all bark so far

Tropical Weather Outlook Map

Tropical Weather Outlook Map

Taking a look at the latest Tropical Weather Outlook map from the National Hurricane Center, one might think that things were really busy. In one sense, things are busy, with plenty of suspect areas to monitor. On the other hand, with the exception of Gordon, which passed through portions of the Azores as a hurricane, looks can be somewhat deceiving as there is nothing brewing right now that poses any significant threat to land areas.

As I mentioned, Gordon moved through the Azores last night as a hurricane and continues to move eastward where it will weaken over cooler waters, falling short of affecting Portugal.

The system that has the most attention right now within the hurricane blogosphere is 94L. It still lacks any deep convection and is surrounded by an awful lot of dry air which has been the calling card of the deep tropics this season. Neither the GFS or the ECMWF strengthen it much as it passes through the Lesser Antilles and in to the eastern Caribbean. It is also worth noting that the GFDL and HWRF both keep it weak as well. Granted, the statistical SHIP model does make 94L a hurricane but it has not done so well with intensity this season, so I discount that for now.

I think the environment is just too hostile right now, mainly the lack of deep moisture and resulting absence of vertical instability. This is a major factor and even though wind shear is light and we’re in the latter part of August, if the atmosphere is too dry, convection cannot commence and sustain and the entire process will never really get a good start. So until and unless we see a change in the thermodynamics of 94L’s surroundings, it will likely be a weak area of low pressure as it moves westward. I would think that we will begin to see an increase in convection as it moves towards higher ocean heat content in a day or so. Keep in mind too that 94L has a large envelope of energy that it has to bundle and focus around a common area of low pressure. In other words, it has a lot of work to do before becoming much of an issue for anyone. This is good news and for now, it should stay that way.

Elsewhere, 95L is along the eastern Mexican coast and poses little more than a rain threat for portions of Mexico. I doubt it will ever get back out over water enough to amount to anything and none of the reliable models indicate much happening.

Then we have 96L out near Africa. All I can say is read back about 94L and there you go. Anything coming out of the deep tropics so far has struggled and I see no reason why that will change anytime soon. Obviously, it bears watching as it tracks steadily westward but I would not worry about it for at least a week.

I’ll cover all of these areas and more on today’s video blog which will be posted to the HurricaneTrack iPhone app this afternoon. Then, I’ll have another blog post here early this evening, sooner if need be.

Gulf system slow to develop, not sure where it is headed

As you know, 96L is being closely monitored for developments as it slowly moves out of the Caribbean Sea and in to the southern Gulf of Mexico. This morning’s satellite pictures reveal very deep convection associated with the system but it still lacks sufficient organization to be classified as a depression. That being said, the NHC continues to note that pressures are falling in the region while upper level winds are forecast to become more conducive for development.

Hopefully the Hurricane Hunters will fly in to the region today and provide much more data on what the structure and overall organization is with 96L.

The future track and intensity will depend a lot on where a solid low level center develops and how quickly the system strengthens. It is interesting to point out that the SHIPS intensity model indicates a moderate tropical storm and not a hurricane. This is obviously good news especially when we also consider that the usually aggressive GFDL and HWRF intensity models both show a very weak system. This can change and probably will as the low takes shape and gets better organized. At least for the time being, we’re not looking at a potential hurricane – let’s hope it stays that way.

As for where this system will end up? It’s too tough to call right now. Some of the model guidance suggests a track in to the central Gulf of Mexico with a turn back to the west and even south of west towards Texas/Mexico. Other models keep the would-be storm heading towards the northeast portion of the Gulf, with possible impacts in Florida. Right now, everyone along the Gulf Coast should just keep an eye on what goes on with 96L today and tomorrow. It’s not moving very fast and there will be plenty of time to react and prepare if needed.

I am on the road today and tomorrow but will post updates regularly. Fortunately, the rest of the tropics remain nice and quiet.