Upcoming week - October 4-10

[Andrew92]

Evaluating last week:

This past week was a somewhat rough week, though it did have a couple bright spots. Starting with the Nicole forecast, I predicted its depression to develop on Monday, being designated at the 11 PM advisory. It did develop on Monday, but at the 11 AM advisory instead. Still, I said that would happen south of the western tip of Cuba, due east of Cozumel, and that’s pretty much where that happened. I also predicted it would become a tropical storm at the 11 AM advisory on Tuesday, and that indeed happened when I said it would. However, I predicted it would happen closer to western Cuba again, but it slid northeast and did so near central Cuba instead. Maximum sustained winds were no higher than 40 mph, a little outside a 45-50 mph window for Cuba and 50-65 mph for Florida. And speaking of Florida, I predicted a landfall near Naples, but the eastward motion kept it just offshore. I also predicted quite a rain event from Nicole in Florida, but it was more concentrated east of the center, in Jamaica, Cuba, the Bahamas, and then later North Carolina as a non-tropical entity. I did predict accurately the dissipation method, that it would be absorbed into a trough of low pressure. It happened closer to Florida on Tuesday, not the Carolinas on Saturday like I said. So I was off on a little of everything really with Nicole but the early development time and location were accurate, as was the method of dissipation. This was not a terribly good forecast, but I did at least have a grasp of what was happening and I acknowledged the forecast would be a difficult one. I did also pick a very good analog in an unnamed storm from 1953 at around the same time. Leslie from 2000 was also not a bad choice either. I give myself a C for this part of the forecast.

PGI48L was a tropical wave that I predicted would not develop. It became Invest 97L, but has become no more than that so far. Therefore, I give myself and A here.

I did predict a Caribbean development on Sunday, and there was a disturbance that, with more favorable conditions, might have pulled it off. However, it fizzled out instead. I gave into some models that were suggesting it could happen, but it turned out to be a phantom, and I give myself a D for this part of the forecast.

But elsewhere, nothing developed as I predicted, so I get an A there.

This past week centered around Nicole. It wasn’t that great of a forecast, but the setup was complicated and harder to pin down. However, nothing else was really threatening to develop except maybe PGI48L, but that didn’t come to fruition as some suggested (but not me). As I said, this was a pretty rough week, but had a few bright spots here and there. I give myself a C+ for this week.

Here’s hoping a new week can get me back at least into the B range that I consistently stayed in throughout most of September. Here we go!

Current situation and models

Invest 97L looks kind of organized near the Lesser Antilles, but will have to survive some very strong wind shear if it wants to develop. That said, a lot of the global models, if not all of them, eventually develop this disturbance down the road. If it does, there is also a pretty unanimous agreement that the system will re-curve, and quickly at that. There are some disagreements on intensity, and the shear could let up, but the general consensus seems to indicate that this will be no more than a moderate to strong tropical storm.

Elsewhere, the NHC is watching another area of disturbed area behind Invest 97L. I’m not seeing anything in any of the models that suggests this will develop anytime soon, however.

Some of the global models, such as the Euro, seem to be hinting at a low pressure area potentially trying to organize during about the weekend in the western Caribbean. However, per what some Pro Mets are saying, the MJO will likely be in an unfavorable phase for development in this region. It’s something worth looking into, though.

Recent history

Invest 97L would most likely develop a little north of the Lesser Antilles and Puerto Rico. Since 1995, there have been two storms developing in similar locations that could serve as analogs for this disturbance: Fabian in 1997 and Henri in 2009. Neither were particularly strong, with Fabian gathering maximum sustained winds of 40 mph and Henri reaching 50 mph. Fabian re-curved, while Henri dissipated to similar shear than Invest 97L will have to endure if it wants to develop.

Looking farther east behind Invest 97L, a look at storms forming in that area during this upcoming week reveals very few since 1995. Included would be Pablo in 1995, Lisa in 1998, and Jerry in 2001. Only Lisa became a hurricane, and very far to the north after re-curving. All three storms were disorganized in this part of the world, too. That said, if one goes just a bit further back, one finds a big name: on October 10, 1988, a tropical storm named Joan developed in a similar location – though it didn’t really get going until about a week later, in the southwest Caribbean. Yet, this wave has one more thing working against it, which can even be seen when look back earlier this very year. It is right behind Invest 97L, and waves coming right behind big disturbances or developed storms usually just cannot do much. Even Earl needed to get quite a bit further west and away from Danielle in order to organize further, and Fiona struggled to become a strong tropical storm right behind him. Jerry from 2001 would also fit a similar mode, as it was right behind the intense Hurricane Iris.

And speaking of the Caribbean, during this upcoming week, there have been a couple of developments from that area: Roxanne in 1995 and Iris in 2001. Both became major hurricanes before their landfalls in the Yucatan Peninsula. Both also developed earlier in the week than the proposed low would even be organizing, per the models.

So what does this all tell us?

When looking at Invest 97L, the chances aren’t too good for anything significant. Only a couple of storms have even developed in a similar location, and neither was very strong. One re-curved and was absorbed, and the other just fizzled out. The models do think this will develop, but are suggesting the re-curve scenario, so Fabian from 1997 will likely be the best recent analog for Invest 97L. That’s not saying a lot for this disturbance now, is it?

As unimposing as Invest 97L is, its competition right behind is even less so. It’s just not favorable to see development in the MDR during this time of year. Yes, Joan survived, but models don’t pick up on this wave at all. In fact, I think Joan is quite an outlier when looking at this part of the world, considering she also ran into land on the way to becoming the big storm she eventually would transform into. When also looking at Jerry from 2001, yeah he developed, but also quickly fizzled behind an admittedly more intense storm, but the idea is probably taken by this point. The odds are firmly against this wave.

And when analyzing the Caribbean, it gets more favorable during this upcoming week, but the conditions are usually not all the way there yet. The low that could try to develop per the models could exist there by then, but the models aren’t doing too much with it, at least for now – they merely suggest it could be there.

Back to looking ahead

OK, after a rough last couple weeks, it’s time to try to hit a home run. It looks easy on paper this week, with a lot of non-developments. But there is Invest 97L; yet, even that one is looking not too significant either. Still, I will try to do the best I can on this system, weak and “fishy” as it will probably be when all is said and done. I predict that Invest 97L will be very slow to develop early in the week due to enduring strong wind shear. However, I do predict development into a tropical depression on Thursday just north of Puerto Rico. On Friday, as it already heads to the north and north-northeast, Tropical Storm Otto will develop out of this system. Otto will be a short-lived system as it then heads northeast to the south of Bermuda, becoming extratropical or absorbed in a frontal system by Sunday. Maximum winds will be no higher than 45-50 mph, occurring on Saturday. Confidence is 75%.

When looking at Invest 97L’s little brother behind it, it’s a simple prediction: I predict this wave will not develop this week. Confidence is 90%.

And looking at the Caribbean, yeah it might be there by the weekend, but that doesn’t mean it does anything, at least right away. Climatology does say the peak is coming, but models are not fully buying this proposed low, at least just yet. The MJO is also predicted to be in an unfavorable phase for development in this part of the world during his upcoming week. After it appeared per models something similar would come for this past week, I’m taking my education from these weekly forecasts to heart. I predict no development in the Caribbean this upcoming week. Confidence is 90%.

Elsewhere, I predict no tropical cyclone development. Confidence is 90%.

-Andrew92

[Andrew92]

Actually, I'd like to add one more thing: Invest 97L will also be a rain threat to the Leeward and Virgin Islands, along with Puerto Rico. However, I predict the strongest winds will stay north of there.

OK, truly done now.

-Andrew92

[Macrocane]

I agreed with you last week that another storm was going to develop from the monsoon gyre but the models really fooled us

This week I agree with you again and I think that 97L will become Otto but I think it could be a 60-65 mph tropical storm. Let's see if the forecast verifies this time. Thanks for the analysis.

[Andrew92]

I have just recently lost the Internet at home as our router malfunctioned and I had to get a new one, but we haven't installed it yet and are going to have a friend help us out with it. It may not happen today, and I am currently at a Starbuck's typing this and may therefore not get a chance to do this later today. With wanting to have this done on a Sunday and to be honest, I don't think 98L becomes a depression before the day is up, I am going to go ahead and post my evaluation now, and in just a few minutes have this upcoming week's prediction.

This week centered a lot around Otto. When looking at how I did on Otto, it was a bit of a mixed bag. I was off on the development time by 24 hours, but the location was accurate, along with an addendum post indicating a flood threat to the Leeward and Virgin Islands, and Puerto Rico. The storm also got a lot stronger than I expected; I predicted 45-50 mph at the strongest and occurring on Saturday, and Otto became a decent hurricane on Friday (though I don’t think I would have ever predicted Otto to gather 85-mph maximum sustained winds at any point). I predicted the re-curved would begin on Friday and it did, but it was already heading east-northeast to northeast by then, whereas I predicted a north to north-northeasterly movement that day. Still, the location of the track was excellent, and from there on I expected a short-lived storm, becoming extratropical by today. Indeed, the last advisory has been written, this very morning. Overall, intensity was way off, but the track was generally executed well. I give myself a B- for the Otto portion.

Elsewhere, I predicted no other tropical cyclone development, from a wave behind Otto to the Caribbean, to elsewhere in the Atlantic. Invest 98L is threatening to develop, but hasn’t done it yet, so I give myself an A for these categories.

When combining the Otto prediction and the accurate predictions elsewhere, this was a decent week overall. I give myself a B+ for this week.

October 11-17 in just a few!

-Andrew92