WxWatcher007

Even though the motion has been erratic, the second trough is a virtual lock to kick this northeast later in the period, much like the current W. Caribbean AOI. It would take a medium range guidance bust of historic proportions—across all guidance for Franklin to become a threat to the US. Atlantic Canada should certainly pay close attention, however.

I can’t tell after the last few seasons

Considering that virtually every other region has baked well over 100 this season, it’s incredible we didn’t see higher highs. Never got the heat dome east.

There was basically no development and no people (relative to the population now) there. As long as they were away from water many probably would have been ok. Not sure but here’s what they did for the more recent record. https://www.aoml.noaa.gov/hrd/data_sub/re_anal.html

It’s hard to imagine anything close to that rolling up the coast. Just insane.

.02 today

Throwback to the OG hurricane in New England

Took the GFS a while to get on board but now it essentially is. Now the questions are how long it takes for consolidation to occur, which obviously has significant implications on intensity in the Gulf, and how likely is this to scrape the SE coastline before likely getting kicked OTS. There’s vorticity, but not much in the way of convection this morning. https://tropic.ssec.wisc.edu/real-time/atlantic/movies/wg8vor4/wg8vor4_loop.html

All the Cat 5’s to hit the US were TS three days before landfall. That’s incredible to me.

First time the GFS has a quicker consolidation of vorticity in the Gulf. Still delayed development until it’s right on the FL coast, then basically OTS.

PRE?

For posterity when this slides harmlessly OTS after Florida

For our Atlantic Canada folks.

12z Ensembles

Let's take a closer look at our latest area of interest that's expected to move into the western Caribbean and Gulf. The NHC now believes that TC genesis is more likely than not, and with increasing run to run consistency from some operational guidance and ensembles, a forecast for TC genesis is coming into view. 3. Northwestern Caribbean Sea: A broad area of low pressure centered over Central America is forecast to move into northwestern Caribbean Sea by this weekend. Some gradual development of this system is possible thereafter into early next week, and a tropical depression could form while it moves slowly northward, entering the eastern Gulf of Mexico. * Formation chance through 48 hours...low...10 percent. * Formation chance through 7 days...medium...60 percent. I've actually been looking at this region and time period for a little over a week now, as a complicated interaction between an EPAC monsoon trough and broader Central American Gyre (CAG) increased the odds that something could form in the EPAC or Atlantic basin. Normally, we see the CAG a few times a season, usually at the beginning or end of the season, but this time we have the setup during the building climatological peak of the season. Much like the monsoon trough in the eastern MDR last week, the EPAC monsoon trough (ribbon of vorticity) is expected to break apart into distinct areas of vorticity, with one lifting north into the western Caribbean and eventually the eastern Gulf under the influence of an upper level trough. This is where the rubber meets the road. We have a clear area of strong vorticity in Central America and that is gradually moving north. For the last week, the guidance had virtually no run to run consistency over whether a tangible feature would move into the Atlantic basin, let alone develop. Usually, the GFS goes wild with CAG TC formation, but has been silent on development. Now, virtually all major guidance has TC genesis taking shape while the GFS, seemingly behind, does put a disorganized area of vorticity into the Gulf a few days from now. At least today, while the GFS and Euro diverge on development, they are closer than it would appear looking at the general setup. Let's look at the next seven days. The GFS, with more shear and less concentrated vorticity making it to the western Caribbean in a few days takes much longer for a surface feature to develop. The Euro on the other hand, has started to show run to run consistency with lower shear and a more concentrated area of vorticity, leading to development in the eastern Gulf even if the area of vorticity spends time over the Yucatan. Even with the upper low nearby, it is expected to shift west, reducing its influence. In addition, over the region we have an upper-level anticyclone allowing for a pocket of low shear and convective activity. That feature is not expected to go anywhere. Unlike other eastern MDR systems, dry air and subsidence has not been as much of an issue further west, and the influence of the SAL had dramatically diminished, as I posted about a few days ago. Alright, so the Gulf is a furnace so that settles it, right? Hurricane coming? I think it's important to look at what could inhibit development, and I think it's land interaction. It's quite possible that if there is a weaker area of vorticity like the GFS predicts and it lingers over the Yucatan or Central America until a northeast trough pulls it north, there may not be enough time for it to organize, much like it was for Harold this week in the Gulf. That said, I think that's an increasingly low likelihood, so let's talk briefly about what happens after potential development. On the 12z Euro you see the trough that is going to kick TS Franklin OTS or toward Atlantic Canada also allows for whatever develops in the Gulf to lift N/NE. On the Euro, the system hugs the coast before swinging out to sea off the Carolina coast. Other guidance has a different trough orientation/timing that allows for it to come further up the coast. What happens is up in the air, but this is looking like something to watch in the Gulf and along the SE coast. We're going to know pretty quickly which guidance is more correct, as the vorticity lifts north. Watch out for where it lands and how consolidated it is in the next 48-72 hours. I've liked the last week of August for close to home activity for a while now and it looks like that's coming to fruition. How strong the activity is and how much of the coast is impacted remains to be seen.

As nice as this summer has been at times, I do feel like we’ve missed out a bit. No big heat while the Midwest and south have baked. Some severe but no region wide high end event like the Mid-Atlantic moderate. We did flood though.

Worth noting that both the operational GFS and Euro have continued trending toward a direct Atlantic Canada impact in about 6-7 days. That leaves a lot of time for changes but the east trend a few days ago completely reversed.

First time we’ve been seeing run to run consistency on actual development. GFS has vorticity but never gets development going. It’s a complicated forecast, but I do think something is going to lift into the Gulf.

Still worth watching Franklin up there, though it looks like we may be settling on more Newfoundland impacts.

I’m not. I do think something’s going to lift into the Gulf though.

Need the Euro to follow the Canadian

Absolutely wild to record a wind gust that high

Central American Gyre. It’s a broad area of spin over the region that usually appears a few times a year but mostly late season. You can get homebrew spin ups from it in the Atlantic or EPAC but forecasting TC development from it is notoriously difficult. Even on the less bullish GFS, the broad vorticity is there. In the area right above the bottom arrow, you can see higher vorticity in the EPAC that’ll likely spin up. As a monsoon trough on the EPAC side (ribbon of higher vorticity) continues lifting north, it’ll bring more vorticity to the Atlantic. Whether something pops is anyone’s guess. It’s far more complicated than I just described. https://tropic.ssec.wisc.edu/real-time/atlantic/movies/wg8vor4/wg8vor4_loop.html In recent years some of our big dog storms in the Atlantic (Michael/Ida) have come from a CAG. Not saying that’ll happen here but a spin up in the western Atlantic and eastern Gulf would be primed since you have high end OHC and would probably need a low shear environment for even a seedling to organize.

Toss that, but I’ve been looking at potential from a CAG in that region for the last week of August going back a week now. A system in the eastern Gulf into the SE region wouldn’t surprise me. From there probably OTS but who knows. If we get anything this year, it’s not coming from a long track MDR wave IMO with the difficulty we’ve seen getting a proper WAR. It’s homebrew or bust around here.