93L slowly getting better organized over the tropical Atlantic

A look at the various track guidance showing a potential threat to the northern Leeward Islands in the coming days

A look at the various track guidance showing a potential threat to the northern Leeward Islands in the coming days

Invest area 93L continues to get better organized, albeit slowly, as it tracks steadily off to the west. There is not a lot of deep convection or thunderstorm activity noted in satellite imagery. This may be due to the marginal sea surface temps coupled with the fairly dry air in place over the tropical Atlantic.

Computer models continue to indicate that this system will become a tropical depression and likely a tropical storm before the end of the week. How strong it gets remains to be seen. Water temps gradually warm the further west it tracks but the dry air and lack of deep convection could stall any rapid strengthening. It is interesting to note that some of the intensity guidance suggests this could become a hurricane while others actually weaken the system later in the forecast period. This just goes to show how little is really known about how tropical cyclones function, especially when it comes to intensity.

The track forecast seems fairly straight forward. Right now, the low pressure area is moving off towards the west at a steady pace. I see no reason for this to change much in the coming days. Eventually, it should begin to gain more latitude and begin tracking more to the west-northwest with time.

It looks as though the would-be tropical storm could impact portions of the Leeward Islands in about four days. The timing and strength, of course, is tough to call right now. I remain somewhat skeptical that this system will develop as much as some of the models indicate, only because this region of the Atlantic has been so hostile for development over the past year or two. Obviously, interests in the Lesser Antilles will need to keep a close watch on how things progress over the next few days.

In the longer term, the pattern over North America will likely dictate where this system ends up. A very strong trough of low pressure has carved itself out over the eastern parts of the United States, bringing much cooler conditions to a wide area of the country. Meanwhile, over the Atlantic, a fairly potent ridge of high pressure is in place which is currently helping to steer 93L westward.

There seems to be a growing number of computer models that indicate a more westward track beyond the five day time frame. If the deep trough lifts out and the Bermuda High builds back in sufficiently, then we could see a track farther west with a potential threat to the Southeast coast of the U.S. It is just too soon to know with any degree of certainty and a lot will depend on how strong the system ultimately becomes. Typically a weaker storm will move more west with the lower level flow while a deeper, more intense storm or hurricane would likely feel any weakness in the Bermuda High more and turn more north.

No matter how you look at it, the next five to ten days has the potential of being quite interesting for many people from the Caribbean to the East Coast of the United States. The best bet is to just keep up to date on the latest developments and react accordingly. With so much information out there these days available at your fingertips, it’s easy to get caught up in model mania. No matter what the computer models say now, we know they will change with time. This is a dynamic situation and we don’t even have a tropical depression yet – though it’s probably only a matter of time.

For now, we have several days before any potential impact to the Lesser Antilles. Let’s see what happens over the next 24 hours and whether or not 93L actually develops further. The rest will take care of itself. I’ll have another update early this evening.

M. Sudduth 8:45 AM ET July 29


Bertha by mid-week? Seems likely at this point

NHC graphic showing potential path of developing system in the Atlantic, designated as 93L

NHC graphic showing potential path of developing system in the Atlantic, designated as 93L

The tropics are about to get active and this time, it could stick.

The NHC is monitoring a tropical wave, now designated as invest area 93L, far out in the deep tropics. While this region has been quite hostile up until now, it appears that the tables are about to turn and we will likely get the next named storm, Bertha, within a few days.

Global computer models are coming in to agreement that the tropical wave will develop steadily in the coming days as it moves generally west to west-northwest.

Water temps are okay for development but are certainly not running above normal in the region. This might keep the system from developing faster, we’ll see. The presence of dry air all across the deep tropics may also inhibit development even though there are indications that this pattern is about to let up some.

The track appears to be generally westward with a gradual bend to the west-northwest with time. Keeping this in mind, interests in the Lesser Antilles should be monitoring this feature closely. The NHC’s five day outlook graphic suggests a path towards the islands. After that point, it is just too soon to even begin speculating on where this might end up. We know the drill by now: it could turn north and eventually away from the United States or it could continue west enough to eventually affect land somewhere after a potential encounter with the Caribbean islands.

One thing that interests me quite a bit is the fact that, if this system develops, it would be several weeks ahead of the usual time frame that we look this far east. It would also signify a change in the overall hostile pattern for the deep tropics. In short, this could indicate that we are in for a different hurricane season than originally forecast. The El Nino failed to develop thus far and now that we are seeing development in the deep tropics, it may be that the forecast of a below average season is in jeopardy. I do not want to put too much in to this but considering just how hostile the region between Africa and the Caribbean has been for the past year at least, I do wonder if we are seeing a change that could lead to more long-track systems that do not fall apart.

The rest of the Atlantic Basin is quiet as we start the week. I see nothing to worry about anywhere outside of 93L.

In the east Pacific, things remain quite busy with weakening TS Hernan moving away from the Mexican coastline. Other areas to monitor dot the Pacific but none pose any significant threat to land right now.

I will post another update on 93L later this evening after more information comes out from the global models and the NHC.

M. Sudduth 9:27 AM ET July 28

Two high potential areas for development in the Atlantic Basin

Tropical weather outlook map showiong 92L and 93L

Tropical weather outlook map showiong 92L and 93L

The NHC has outlined two areas, 92L and 93L, for potentially becoming the next tropical depression in the Atlantic Basin this evening. Neither pose a significant threat of impact to land for the time being.

Looking at satellite images of 92L, which is located in the western Caribbean Sea, the organization trend appears to be continuing. It won’t take much to get this system to tropical depression status. The NHC reports that winds are already gusting to gale force within the heavy rain bands to the east of the broad center of circulation. The main impact here will be rain and occasional gusty winds for portions of the Caymans, western Cuba and the Yucatan.

So far, the advanced global models are not impressed with 92L and do little with it over the coming days. On the other hand, some of the regional, hurricane-specific models create a hurricane out of the system. This seems unlikely considering the nature of the upper level winds across the Gulf of Mexico as we round out the week. However, water temps are very warm across the region and intensity forecasting is the weak link in the overall hurricane forecasting process. Odds are this system remains weak and lopsided, with most of the worst weather to the east of the center. We shall see.

As far as track goes, here again, the models are of little help since the global models do not show much of anything to begin with. A track generally northwest and eventually over the Yucatan seems likely tomorrow and Friday. Beyond that time, we’ll see what’s out there before worrying too much about where it goes.

In the far eastern Atlantic, 93L continues to become better organized and should become a tropical depression before the weekend. Its track seems to be westward over the open Atlantic with no impact to land except for portions of the Cape Verde Islands. We’ll have plenty of time to monitor this system as it moves westward.

I’ll post more here tomorrow morning on both systems.

M. Sudduth 8:05pm ET August 14

92L in the Caribbean likely to bring a lot of rain to Yucatan as tropics begin to ramp up

Computer model plots for 92L courtesy of Hurricane Analytics

Computer model plots for 92L courtesy of Hurricane Analytics

Invest area 92L is looking more organized today with deep convection taking on a more curved look in satellite imagery. Also noted is a more well established upper level outflow pattern. This will aid in the development of this system over the next couple of days while conditions remain favorable over the very warm waters of the Caribbean Sea.

The NHC notes that a low pressure center may be forming somewhere between the Caymans and the Yucatan. The low is forecast by most of the computer models to move to the northwest and possibly cross the Yucatan and in to the Gulf of Mexico. This means that a lot of rain and some increase in wind is headed for the region today and tomorrow. Interests in the area need to be aware of this large weather system and understand the rain threat is significant. Fortunately, it does not look like 92L will have much chance to rapidly strengthen but it wouldn’t take much for it to become a tropical depression or tropical storm.

Beyond the next 48 hours, the track is quite uncertain. Some of the model guidance indicates a track towards the U.S. Gulf Coast while others are more west towards Mexico. As we have seen so many times before, it will come down to the timing of how an upper level trough interacts with the system over the coming days.

If the trough can create a weakness in the steering pattern to the north of the disturbance, then it can have a hole, if you will, to move in to and thus towards the Gulf Coast states.

On the other hand, if the trough is not strong enough to erode the high pressure to the north of the disturbance, and the high actually builds back in once the trough lifts out, then it will get pushed westward across the Bay of Campeche and towards Mexico. There’s no way to know which scenario will play out – we’ll just have to wait and see. Right now, most of the reliable guidance is pointing towards the Gulf Coast but this can change as more data becomes available for each new run of the models. If you live along the U.S. Gulf Coast anywhere from Texas to Florida, just keep an eye on this feature over the next couple of days. As I said, intensity forecasts from the various models do not indicate much chance for strengthening and hopefully that will remain the case. We’ll watch and see how things progress today and tomorrow.

Elsewhere, we have invest area 93L far out in the eastern Atlantic. This system has a solid chance of becoming a tropical depression before it moves in to a more stable environment where the mid-level air is drier. It’s only of concern to interests in the Cape Verde Islands right now.

All of this activity is part of the pattern that is slowly beginning to unfold across the tropics. We’ve seen a lot of storm activity in the Pacific, now it’s the Atlantic’s turn. The next several weeks are likely to become increasingly busy throughout the Atlantic as there are signs that the upper level pattern is about to become quite favorable. Despite all the talk of dry air, dust and a lack of activity, it is still going to be a very busy season. There are just too many overwhelming signals in favor of that to be ignored. Now is the time to be prepared. Take that generator to a small engine repair shop to have it looked at in case you need it later. Do the little things now that can help alleviate the stress that comes with an approaching hurricane. It’s about to get very busy out there and as such, people need to be ready.

I’ll have another post here later on this evening.

M. Sudduth 1pm ET August 14

Vigorous tropical wave bringing rain to portions of Central America

Invest 93L in the northwest Caribbean Sea. Most computer models indicate a track across Central America and in to the Bay of Campeche this week.

Invest 93L in the northwest Caribbean Sea. Most computer models indicate a track across Central America and in to the Bay of Campeche this week.

The NHC has increased the probability of development for the tropical wave passing over portions of Central America to 40% this morning. Showers and thunderstorms have steadily increased with the system over the past 24 hours and if it were not for the land mass in its way, it would be a depression by now.

As it stands now, there is quite a bit of land in its way and this will preclude any significant development for the next day or so. There is a chance that the wave energy emerges in to the Bay of Campeche where it will have a chance to develop in to a depression or tropical storm.

Most of the computer guidance suggests that a track over the extreme southern portion of the Bay of Campeche is likely before finally reaching Mexico again on the western side of the bay later this week.

Water temps in that region are plenty warm and upper level winds are becoming more and more favorable. It won’t take much for this system to become a tropical depression or even a moderate torpical storm if it can get free of the land interaction it is dealing with now.

The main impact right now will be heavy rains for areas of Central America, including Belize and the Yucatan. This will spread westward over the next few days and it is possible for several inches of rain to fall across the region.

As for any possible impacts to the U.S. go, we can thank a fairly strong ridge of high pressure to the north of the tropical wave for keeping it on a general westward course. None of the computer guidance indicates that it will gain much latitude this week and so it appears that even south Texas will remain clear of any ill-effects from this weather feature.

The rest of the tropics, including the east Pacific, are nice and quiet as we begin the week. I’ll post more here this evening.

M. Sudduth