Upcoming week - August 22-28

[Andrew92]

The following post is NOT an official forecast and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

VERY important to keep that in mind, and there will be other red disclaimers in this week's outlook with what Irene could do this upcoming week.

Evaluating last week

I’m not going to mince words. No more of last weekend and not getting to analyze the models at all. The Gert prediction was only OK at best as it didn’t get quite as strong as I thought and it weakened faster than predicted, though the track was right on at least. Elsewhere I predicted no tropical development. Well, thanks both Harvey and Irene for totally messing that up. I also didn’t see Invests 98L and 99L, though mere Invests have no bearing on that area. Still, this past week’s grade is a nice solid F.

What a morale booster coming into the toughest week yet this year (insert sarcasm). Let’s take a look.

Current situation and models

So we have this little thing called Tropical Storm Irene hitting Puerto Rico and the Virgin Islands right now with maximum sustained winds of 70 mph. The NHC forecast does not explicitly say Irene is supposed to become a hurricane before striking or clipping the Dominican Republic on Monday, as it has 70 mph maximum winds in the Mona Passage – however, it easily could become one before reaching there. It should weaken some over the northern coast of Hispaniola, but how much will depend on how long it spends over that mountainous island. Still, beyond that, several reliable models, including the Euro, GFS, and HWRF, are really intensifying Irene into quite possibly a monster hurricane. The track is another animal in and of itself. The GFS has consistently taken Irene into Florida, but has been shifting east. The Euro has pretty consistently kept Irene east of Florida for a landfall in South Carolina between Charleston and Savannah, Georgia. The HWRF takes a similar track to the Euro. However, the UKMET and GFDL are taking Irene along a ride through Cuba and eventually into the Gulf of Mexico. From there, Irene would then impact South Florida, likely as a decent hurricane though not like if it follows the Euro, GFS, or HWRF. For now, the NHC is being conservative on intensity and tracking it toward South Florida after clipping the north coast of Hispaniola, landfalling Irene as a C1 hurricane with maximum sustained winds of 90 mph in Palm Beach County, and then riding up the coast and still having 85-mph maximum winds into the Jacksonville area. However, one cannot look at the line for the exact track; rather, focus on that larger cone of uncertainty and listen to the NHC and your local authorities for how you should prepare for this potentially very dangerous storm.

Elsewhere, Harvey has re-emerged into the Bay of Campeche and may have just enough time to strengthen into a minimal tropical storm before making landfall near Veracruz early Monday morning, and then dissipating on Tuesday. Invest 98L is still out there but heading northwest over cooler waters and an unfavorable environment and does not look like it will develop. Also, while it is getting to be the time of year to really look off the African coast, no models are showing anything yet this upcoming week. The GFS does eventually show development in a couple weeks, but that is for much later.

Lastly, with the kind of season it’s been so far, it would be a crime to not look at a potential frontal system churning out another weak tropical storm. There actually was some chatter about such a development a couple days ago from a system off the East Coast. That system is now near the Maritime Provinces, and develop would seem very unlikely at this point. Elsewhere, there are no hints of any fronts popping off any tropical developments over this upcoming week.

Recent history

As Irene is currently situated over Puerto Rico and the Virgin Islands as a strengthening tropical storm, heading towards the Dominican Republic, let’s try to find another similar storm to what Irene may do. Some storms in a very similar position in terms of location and track during this upcoming week would include:

Cleo in 1964
Faith in 1966
Doria in 1971
Chris in 1988
Bonnie in 1998
Dennis in 1999
Debby in 2000
Dean in 2001
Ernesto in 2006
Gustav in 2008

There are three storms in the set that may raise some eyebrows. I included Dennis in 1999 due to the closeness of the forecast track, and Ernesto and Gustav for an idea of what the interaction to Hispaniola might look like for Irene.

With that, let’s look at the tracks first. There are three storms that likely can be thrown out if the models and forecasts are accurate: Faith, Dean, and Gustav. Faith and Dean re-curved back out into the Atlantic, while Gustav went much further west than Irene is forecast to reach, going as far as Louisiana. The furthest west any model takes Irene is the west coast of Florida. Of the others, Cleo takes the southernmost approach to Florida, with Ernesto right close behind. I don’t buy that Irene will follow a path like Cleo’s as that would mean staying south of Hispaniola, and Ernesto’s is probably right there with it as it approached Hispaniola from the south. Debby just dissipated near Hispaniola, which is definitely possible as Emily never recovered from there earlier this year. However, Debby and Emily were smaller storms with less favorable environments; Irene is much healthier looking, has a nice environment to work with, and no model dissipates Irene after Hispaniola.

That leaves Doria, Chris, Bonnie, and Dennis, so we’ll more closely analyze those four down to intensity. Doria and Chris didn’t get going until they were near their Carolina Coast landfalls, and they were practically both right over where Irene currently is. However, Doria and Chris were tropical depressions struggling to get going; Irene is on the verge of becoming a hurricane. A better choice of analog may be Bonnie in 1998. That storm was admittedly a hair north of where Irene was and more or less clipped the Virgin Islands, but had a similar intensity and from there followed an extremely similar path to the East Coast that Irene could take. Bonnie also went on to become a C3 hurricane during this upcoming week back in 1998, with winds as high as 115 mph. Of course, Bonnie did miss Hispaniola altogether, but this still looks like a solid analog, with a track a bit further south. Dennis is also a solid analog, despite not forming until the Bahamas. It went on to become a C2 hurricane with maximum winds reaching as high as 105 mph, but it re-curved, which Irene will likely not do before landfall. Yes, it did later loop back into North Carolina, but that was very unusual.

I did want to go back to Ernesto and Gustav for one other thing though. Should Irene clip Hispaniola like models say, what will it do from there? Ernesto was very slow to recover, but eventually did just before a landfall later on in North Carolina as a tropical storm (though helped out by crawling along the Cuba coastline and then striking Florida). Gustav also took a couple days to recover, but when it did it blossomed into a monster in the Caribbean before nailing Cuba, also a little later. It is possible that Irene could be in that position if the UKMET and GFDL are right, so that needs to be considered. However, it appears highly unlikely.

Also, maybe I should just go back to Faith and Dean for one more quick look with respect to intensity. Dean looks like a very poor analog in that regard as it de-generated into a remnant low quickly (though did re-form later). But Faith, like Bonnie, did become a C3 hurricane with maximum winds reaching 125 mph.

Finally, the two storms that strengthened beyond C3 intensity were Cleo and Gustav; both did so in the Caribbean only during this upcoming week or a bit beyond.

So what does this all tell us?

For one thing, Hispaniola will make or break Irene. If the models are accurate, Irene should survive Hispaniola and intensify into a monster hurricane heading through the Bahamas and towards Florida, Georgia, and the Carolinas. However, the strongest hurricane following a path similar to Irene’s during this upcoming week gathered maximum winds as high as 125 mph. It’s true that this happened further east of Irene’s forecast path, but even Dennis followed a path close to Irene’s and became no more than a C2 hurricane. Therefore I’m not entirely sure this will become the C4 hurricane that some are hyping this up to be. I’m not saying it won’t happen, but after seeing this I am more skeptical about it, especially with what may happen after Hispaniola. Still, I am going to have predict a major storm out of this for somebody beyond there. It is no secret that Florida is very much under the gun for a visit from this potentially dangerous storm. However, a C3 hit for a place like Savannah, GA, or Charleston, SC, could be real trouble for those areas that don’t get hit as often by storms like that than Florida or North Carolina (which themselves would still take a lot of damage).

The Prediction

This is where I am really sweating bullets. I just hate to make a prediction like this, especially coming off the heels of a very much failed last week for me. I would actually rather take another F for this upcoming week that have happen with Irene what I think will happen.

I guess let’s first just knock Harvey out. I predict Harvey will re-strengthen into a minimal tropical storm with maximum winds of 40-45 mph just before landfall a little north of Veracruz at about or a little after sunrise on Monday. It will weaken to a tropical depression quickly, then dissipate overnight into Tuesday. There will be plenty of rain in the area where Harvey hits, and some mudslides are very possible. Confidence is 80%.

Now it’s time for the heart-wrenching part of this week’s prediction. It’s going to be a long week this upcoming week for those potentially dealing with Irene. Before I get to this prediction, I again urge everyone, do NOT treat this as an official prediction! This is strictly my opinion, and given the nature of what I do here, errors are subject to be quite large. Please also consider that I had a very bad week last week and this has been a very difficult year so far for this column. I predict Irene will become a hurricane with maximum winds of 75-85 mph before reaching the eastern tip of the Dominican Republic late Monday morning. Irene will spend about 12-24 hours along the northern coast of Hispaniola and weaken some, down to 60-65 mph by the overnight hours leading into Tuesday. Rainfall will be very heavy throughout the mountainous island on Monday and early Tuesday. Irene will not strengthen again until Tuesday night near the southern Bahamas, and will become a hurricane again on Wednesday. On that day, Irene will be raking the central Bahamas and starting to make a turn toward the northern Bahamas and Central Florida. A more rapid intensifying trend will then start leading into Thursday, with Irene becoming a C2 hurricane before dawn near Andros Island and a C3 hurricane that afternoon just off of Palm Beach, FL. Hurricane winds will have affected much of the central and northern Bahamas, and will now affect Central Florida on this day as the hurricane’s eyewall clips the coast, while the eye stays just offshore. Maximum winds at this time will be 115-125 mph. However, Irene will not strengthen anymore as it turns toward a final landfall between Savannah, GA, and Charleston, SC, early Saturday morning, with a tighter lean towards the area around Hilton Head and Beaufort, SC, if I had to name an exact location. Maximum winds will be around 115-120 mph at this time, and hurricane force conditions will impact both Georgia and South Carolina. Irene will then weaken that afternoon and night over South Carolina to a tropical storm, and the next day to a depression as it heads into North Carolina and Virginia before dissipating by Sunday night, but produce very heavy rainfall along this path with the potential for flooding and tornadoes. Overall confidence is 30% - DO NOT treat this as an official prediction! Rather, stay tuned to the NHC and your local authorities for what to do if in the path of this potentially dangerous system! Thank you.

Elsewhere, I predict no development for Invest 98L or any other tropical cyclones this upcoming week. Confidence is 70% to account for any surprise frontal systems.

-Andrew92

[hurricanehunter69]

Wow! Again, no development expected this week...? I was again very surprised by that man! I would have not only gone with development with 98L, but as a hurricane at that! I would have also gone with not only one, but possibly two more developments coming off Africa. Check out the latest Mimic-TPW imagery! I would have also gone with a 50/50 shot at a surprise spin up in the carribean. Due in part to a wet MJO pulse. I would be shocked if we don't get at least two new developments by the end of this week. Keep your chin up though man! I think that I can speak for a lot of people on the forum, in that we appreciate the time you put into your write-ups, and I in particular enjoy reading them!

[BigB0882]

I also think something else will develop, but who knows, those waves have taken so long to get going that it could be almost a week before the current wave off of Africa turns into anything.

[Andrew92]

Yeah, well now the models ARE of course seeing something developing. If I had a do-over I probably would now call for something. Then again, it has taken a while for some of these to get going, including Irene.

Oh well I guess. Irene is the big one to get. Track through the Bahamas looks promising, though not the landfall location. If I can at least still get intensity up to landfall, might be still an overall decent week. We'll see I guess.

Last year was a really decent year overall for this. This year has been nothing short of frustrating and hair-pulling so far.

-Andrew92

EDIT: Just looked again at that wave that just came off Africa. It has a decent spin to it, but it really poofed upon reaching the water. It will definitely take its time to develop, probably not happening until Friday at the earliest. Also, Invest 98L *might* squeeze out a depression, but I would call for nothing more. Overall, I would stand with a no-show for development on that area.

[cycloneye]

Yeah, well now the models ARE of course seeing something developing. If I had a do-over I probably would now call for something. Then again, it has taken a while for some of these to get going, including Irene.

Oh well I guess. Irene is the big one to get. Track through the Bahamas looks promising, though not the landfall location. If I can at least still get intensity up to landfall, might be still an overall decent week. We'll see I guess.

Last year was a really decent year overall for this. This year has been nothing short of frustrating and hair-pulling so far.

-Andrew92

EDIT: Just looked again at that wave that just came off Africa. It has a decent spin to it, but it really poofed upon reaching the water. It will definitely take its time to develop, probably not happening until Friday at the earliest. Also, Invest 98L *might* squeeze out a depression, but I would call for nothing more. Overall, I would stand with a no-show for development on that area.

Is now invest 90L.

[Andrew92]

Still feeling slowish development at least for 90L, though I'm more impressed by it tonight. Models indicate it is likely to be a fish so I will go with that for now.

-Andrew92

[Andrew92]

OH MY GOSH.....how in the world does Invest 91L become Jose looking like it does?

-Andrew92

[RL3AO]

I think the NHC guys are messing with you.

[Andrew92]

Irene has left the building as of 11 PM. It is time to evaluate, warning too it's lengthy.

Well, this week was pretty much all about Hurricane Irene. My review for this previous week is very mixed. Generally speaking, I had the idea of the track down, with a track near Hispaniola, into the Bahamas, and north from there and re-curving. As I also recall, at the time I made this write-up, there were some models still taking Irene inland further and not really re-curving. The timing of track for the first couple days was also very rock-solid, as I predicted Irene to impact the southern Bahamas on Wednesday, and the northern Bahamas on Thursday. Another major victory was the peak intensity. A lot of models and forecasts kept insisting that Irene would become a very strong C4 hurricane of some sort; however, I wasn’t buying that and went with a C3 hurricane with maximum winds reaching maybe as high as 125 mph. The winds indeed got no higher than 120 mph. Finally, while the location of landfall was far off, it is worth noting that I correctly nailed the time of US landfall, on Saturday morning.

Now for the flaws. I had Irene passing over Hispaniola, but it passed to the north. This also affected the intensity portion a little, as I had Irene weakening to a tropical storm while over there. It is true that Hispaniola still disrupted Irene a little bit, and Irene was only a short distance off Hispaniola and produced some heavy rainfall, as I predicted. But staying offshore allowed Irene to maintain hurricane intensity even when it was somewhat disrupted. The re-strengthening was at first slow as I anticipated, but then Irene ramped up really quickly into a C2 and later C3 hurricane on Wednesday, when I said this would happen on Thursday – again, this is likely a consequence of staying off of Hispaniola. While I did correctly predict no further intensification from there, I did not foresee Irene undergoing as much shear and dry air as it did, and Irene weakened a lot more before US landfall than I could have predicted. I predicted a C3 at landfall, but Irene was a large C1 with winds of 85 mph at landfall. Finally, Irene tracked a fair distance east of what I predicted, showing I probably need to learn more of the model trends coming into the week, rather than just what the models are saying at the time. The models were congregating on South Carolina and I agreed, but the trend was shifting eastward. This will be a lesson I will apply for the future: “the trend is your friend.” I had predicted hurricane conditions in Florida, but the storm brought some rough surf, rain, and light winds – no hurricane winds. The storm also made landfall in North Carolina – one state off of where I predicted. I also didn’t think Irene would move quite as fast to the north as it did after landfall.

Overall, evaluating how I did with Irene, it was very much far from perfect; however, I had plenty of victories with this storm. Some were easy such as the track and timing through the Bahamas, but others were more difficult. Intensity remains the most difficult aspect of tropical systems to nail down; to at least nail down what the maximum intensity would be in the face of lots of predictions for a stronger storm is definitely something I will give myself a lot of credit for. With this all said, I probably did as well of a job with Irene last Sunday with what I had to work with, but it again was still not that great. I will give myself a C overall for this storm.

There was other activity besides Irene, however. Harvey was dissipating in Mexico, and while I did predict a slight re-strengthening before landfall and it didn’t, the effects were still probably the same as if it had done so. I predicted no other developments during the week. Some were very surprised that I made that prediction, and it was indeed wrong. However, it took a fledgling tropical depression that just could not get going, and an Invest that had almost no chance of developing that developed into Jose anyway that did it; it’s not like it was some intense storm becoming a hurricane that tripped me up. Incidentally, there were some predictions of TD 10 to become a stronger storm, even a hurricane. If there’s one thing I could learn a little more, it’s picking up those weak ones that never seem to get going. But overall, the damage for this part of the prediction could have been much worse, and I will give myself a B- for this area.

The B- gets little weight though, and Irene was the bread and butter. I already gave myself a C there, and the B- for everywhere else does not make this a C+ week. My grade for this past week will be a C.

Extended week for Labor Day coming up shortly.

-Andrew92