Upcoming week - September 19-25

[Andrew92]

Evaluating last week

Well, this was another mixed bag overall. We’ll start with Maria. The track was pretty easy to figure out, with a track at first slowly northwest, and then curving north and north-northeast, passing just west of Bermuda but close enough to produce tropical storm force winds, and then over Newfoundland on Friday while becoming extratropical. This was executed nearly perfectly, though the timing of passing by Bermuda was off by a day; I predicted this for Wednesday but it happened on Thursday. However, I was correct in pinning down a landfall in Newfoundland on Friday while becoming extratropical. The real problem was that Maria got stronger than I predicted. I thought Maria would fall short of becoming a hurricane, but reach winds of 60-70 mph. However, she was able to pull it off, and actually reached Newfoundland as a hurricane with winds of 75 mph. It’s not like she became a really strong hurricane, but this did hurt my performance a little with Maria, especially when considering I also thought she would have winds of 45-60 mph upon reaching Newfoundland. To sum it up, the track was good, the intensity not too great.

Elsewhere, I brought up two areas for possible development. I predicted that one would develop, and one wouldn’t. Well, neither one developed. The one I was correct on was the Caribbean development that some models had been picking up on for the weekend. I didn’t go along with it due to inconsistencies in model runs, which was a very good call. However, there was another interesting area to watch out for off the coast of Africa, that I unfortunately predicted to develop over the weekend into Tropical Storm Ophelia. Really, it became a rather bizarre set of Invests 97L, 98L, and 99L, but that’s it. A slight mitigation in this area is at least I saw that conditions weren’t all the way favorable, and I kept Ophelia very weak as a result. But I still thought she might come, and she hasn’t.

When piecing it together, I really kind of did just OK all across the board, with Maria and elsewhere across the Atlantic, though the areas I did well on were done pretty well. Predicting landfall in Newfoundland on Friday that far in advance, and then seeing it come to fruition, is very worthy of an honorable mention. I give myself a C+ overall for this past week.

The tropics don’t look entirely threatening this week, but it is September, so let’s really take a look.

Current situation and models

Well, Invest 97L died over the weekend, but Invests 98L and 99L are still kind of doing a little dance together in the tropical Atlantic. I don’t think either one is really helping out the other get better organized at all, and the environment has already proven to not be exactly favorable for significant intensification in this part of the world this hurricane season. Emily struggled, Irene waited to develop, Katia didn’t really intensify until much later, and Maria just did not want to get off the ground but finally did when she was out of there. Indeed, most reliable models, including the Euro, are not picking up a particularly strong system out of either disturbance, more likely Invest 98L as that one is at least further south. The track looks to be a slow, westward track towards the Caribbean and reaching there by the weekend.

A lot of models are still trying to show something coming from the Caribbean sometime soon, though it easily could be Invest 98L as it reaches there. There is absolutely nothing in the Caribbean to even suggest anything could develop there anytime soon, and I am seeing nothing other than 98L and 99L that could reach there to cause trouble in that area this upcoming week. However, by the end of this upcoming week, nothing really seems to be showing any threats to land or to develop other than that possibility, which has inconsistent model runs at best.

Recent history

How possible is it for either no storm, or a very weak tropical storm (less than 60 mph at peak), to at least occur this upcoming week in the tropical Atlantic or Caribbean since 1960? The following years met either criteria, with ones that had a storm being noted in parentheses:

1960
1961
1962
1964
1967
1968
1972
1976
1977
1979
1980
1982
1983
1986
1990 (Josephine, 45 mph at peak until she got further north)
1991
1992
1993
1997
2001
2007 (Ingrid, 45 mph at peak, and Karen at 45 mph peak by week’s end but she was just forming)
2009

Surprisingly, 22 out of 51 hurricane seasons have either had nothing in those areas, or have only a minimal tropical storm, good for 43.13 percent of all these seasons. It may have been a push to put 2007 in there since Karen was just forming, and then a couple days later became a minimal hurricane briefly, but the point is this happens more often during this upcoming week than one might think.

So what does this all tell us?

With conditions not terribly conducive for development in the tropical Atlantic or Caribbean, anything from no development to a minimal tropical storm is supported by models. But history also says this can happen about every other year, or maybe every three years. Last year, Lisa was intensifying into a hurricane, while Matthew developed into a 60-mph tropical storm in the Caribbean. I know, you can’t just look at trends like that, you have to look at the current, but the current buys into what history says, which I think is overall, the Cape Verde season is wrapping up.

The Prediction

Really, when it comes down to it, it hinges on what Invest 98L and Invest 99L decide to do. I don’t really see any kind of significant development from either…but that doesn’t mean absolutely no development will take place at all. It would probably be Invest 98L as Invest 99L is fizzling out in front. The SHIPS model does show a potential 60-65 mph storm, but the Euro does almost nothing with it. This isn’t a terribly easy prediction, but here it goes. I predict no development for Invest 99L first off. As for Invest 98L, I am predicting a tropical depression to development sometime in the afternoon or evening on Tuesday. Intensification will be very slow at it moves slowly west to west-northwest, but it will become Tropical Storm Ophelia by Wednesday night or Thursday morning. On Thursday, Ophelia will max out in intensity with winds reaching 40-50 mph. On Friday, she will weaken to a tropical depression as she reaches the Lesser Antilles, about near Guadaloupe or Dominica. She will then dissipate shortly after entering the Caribbean on Saturday morning, and never re-generate. There will still be a rain and flood threat from Ophelia in the Lesser Antilles as Ophelia passes through. Confidence is 60%.

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

-Andrew92

[Andrew92]

When looking at this week, Ophelia was the seeming only story, and it was the only one I predicted would develop. I timed the initial development very well for Tuesday. I also timed the peak intensity on Friday, as it happened on Thursday However, I was 24 hours off each for reaching the Caribbean and dissipation. I predicted Ophelia would reach the Caribbean on Friday, but it did so on Saturday. Meanwhile, I predicted dissipation on Saturday, and it happened Sunday. Also, Ophelia got stronger than I suspected. I thought she would be a very weak storm, but actually reached winds surprisingly up to 65 mph. Overall, I’d call this another mixed evaluation, though the storm was still sheared its whole life and it was probably very hard to get that intensity right this go around.

What might have been a B or B- week was ruined though when Philippe developed on Saturday. I didn’t call for anything else, but this storm had to surprise me late. He’s also doing well, with winds of 60 mph, not good at all for my grade this past week.

Overall, when putting it together, I give myself a C- for this past week.

New week coming up.

-Andrew92