GaWx

Keep in mind that besides the last few GFS runs, all other credible operational models keep this very weak for several more days, well into the Caribbean. Also, note that the 18Z GFS is the weakest it has been at the LAs since the 0Z 9/19 run. So, even the GFS is signaling that these last few runs will likely turn out to be too aggressive that far east. Below is the map of TC origins during Sept 21-30 from 1851 through 2015 (I looked and this was also the case for 2016-21), which says that if it doesn't become a TD by the LAs (the likely case right now), it will almost certainly wait at least for another 800-1000 miles after which all bets are off on nondevelopment. I fully expect this to become a big deal by the W Caribbean, regardless:

No, it isn't OTS from FL.

The 12Z UKMET at 144 hours is ~200 miles S of the 12Z Euro 144 position, which puts it ~100-150 miles NE of Honduras moving NW. The UKMET is often on the left side of the model consensus mean: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 114 HOURS FORECAST POSITION AT T+114 : 13.9N 76.4W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 25.09.2022 120 14.2N 77.4W 1004 26 0000UTC 26.09.2022 132 14.6N 79.0W 1003 27 1200UTC 26.09.2022 144 15.6N 80.6W 1002 31

A very dangerous track for Tampa on the 12Z Euro.

The number one target of the 12Z GEFS members is the Gulf coast of FL. This includes quite a few MH hits.

As Superstorm's map shows, the spread is a little wider. The mean is a little further south in the W Caribbean due to a higher number of members in the SW Carib on the 6Z 144 (10) vs 0Z 150 (5).

The 6Z EPS mean at 144 is a little stronger than the 0Z EPS at 150.

This would mean there's a good chance for the FL Gulf coast to be hit by Hurricane Hermine twice in a row after getting the prior one in 2016. The wave E of the Windwards that could turn into Hermine is now Invest 98L and is looking more potent.

The ACE for Sept to date is now up to 35.5, which isn't far from the average 1991-2020 MTD of low 40s. The 30 year average for the full September is 56. Looking at the model consensus, there's a very good shot at exceeding that. What a turnaround from the August shutout!

8 AM TWO up to 10%/50% within 2/5 days now from 10%/40% on the 2 AM for the wave a few hundred miles east of the Windwards while 97L is up to 80%/80%. 2. Central Tropical Atlantic: A tropical wave located several hundred miles east of the Windward Islands is producing a broad area of disorganized showers and thunderstorms while moving westward at 15-20 mph. Gradual development of this system is forecast during the next several days as the system approaches the Windward Islands, and a tropical depression could form by the latter part of this week as the system moves into the eastern and central Caribbean sea. * Formation chance through 48 hours...low...10 percent. * Formation chance through 5 days...medium...50 percent.

Regarding the AEW E of the Windwards, the 0Z UKMET is the 3rd run overall and 2nd run in a row with TC genesis. This has it occur 30 hours earlier than the prior run: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 102 HOURS FORECAST POSITION AT T+102 : 13.8N 71.7W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 24.09.2022 108 13.6N 72.9W 1007 28 0000UTC 25.09.2022 120 13.7N 75.0W 1005 26 1200UTC 25.09.2022 132 13.3N 77.4W 1004 28 0000UTC 26.09.2022 144 13.8N 79.7W 1002 29

The Euro had this earlier than the GFS (back to 0Z 9/13 run) and it had a TS SE of the DR on the 0Z 9/14 run, which you can see here at 240 hours (with Fiona well to the north). It is the same wave: Aside: the ICON and JMA also sniffed it out before the GFS on 9/14.

Per 12Z Euro 240, it appears to be aiming for the FL Panhandle 9/29-30 as a MH.

It made it to lemon status on the 2 PM NHC TWO: A tropical wave located several hundred miles east of the Windward Islands is producing an area of disorganized showers and thunderstorms. Some gradual development of this system is possible during the next several days while the system approaches the Windward Islands toward the end of the week and moves over the eastern Caribbean sea over the weekend. * Formation chance through 48 hours...low...near 0 percent. * Formation chance through 5 days...low...20 percent. Edit: The 12Z Euro has the most impressive 850 vorticity for this AEW in many runs at 72 hours. The 12Z Euro at 120 hours is the most organized for this of any Euro run at that point since the 0Z 9/14 run. 12Z Euro: TS at 168 moving NW in W Car. H at 192. Nearing MH SE GOM 216!

This will very likely be lemoned and Invested soon. Meanwhile, the 12Z GEFS is quite active with this in the Caribbean and about as active as any run so far.

The UKMET (12Z) has this as a TC per the textual output for the second time* as it was also on the 12Z 9/14 run: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 144 HOURS FORECAST POSITION AT T+144 : 13.6N 76.4W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 25.09.2022 144 13.6N 76.4W 1006 26 *Corrected to say this is the 2nd UKMET run with it rather than the first run

I'm bumping this for the record since now nearly all models have this developing to some extent and the 6z GFS has this as a TC within 4 days as well as a MH in the W Car. The Euro had this as an active AEW per the above as far back as the 0Z 9/13 run, way ahead of the GFS. The 240 hour map of the 0Z 9/14 Euro run even had this as a TS SW of PR moving WNW on 9/24 (see image below). Actually, the ICON and CMC had this active though to a lesser extent by the 0Z 9/14 run. So, if this turns out to be something significant in the Caribbean, the GFS will have in retrospect been way behind the Euro. (The just released 12Z GFS is similar to the 6Z GFS with a TC at the Windwards.) Here is the 0Z 9/14 Euro at 240:

This has hardly weakened to this point and the center is going to be over water soon.

There are a significant number (nearly 25%) of 12Z EPS members landfalling on the CONUS 9/29-10/2 as hurricanes or as a strong TS from TX through NC with also a couple of still offshore threats. At least half of these hit the FL Gulf coast, which is my #1 risk area this season based on third year cold ENSO analogs. Being that this was a more active EPS run than prior ones, I wouldn't be surprised if most of the next ones over the next few days aren't as active. Regardless, this will more than likely be the next potential threat period on the CONUS.

With 12 days still to go, Sept is far from a done deal after Fiona, which itself may become a MH. Keep in mind that as recently as September 10th (just 4 days before the Fiona TC formed on 9/14), people here including myself were considering the possibility of no new TC through 9/20 based on then still very quiet models as even the precursor to Fiona was temporarily quieter. Furthermore, the models including EPS are now making some late Sept W Car noise largely from the AEW now near 43W. Especially with the W Car peak season climo already getting started by then, a TC there then wouldn't be the least bit surprising. On 9/10, even Andy Hazelton said this: "Not a whole lot to look at at the climo peak of hurricane season, behind #Earl. 95L fizzled due to shear. The low riding wave is struggling with SAL (EPS refuses to give up on it but color me skeptical). The proverbial #nextwave coming off is already trending weaker on models."

This AEW is now near 42W (very weak low probably ~11N) continuing westbound and has been pretty inactive the last 2 days as dry, stable air has been interacting with it. There's only scattered convection with it now. The 12Z Euro does have this as a weak low in the W Caribbean 9/26, which then moves NW to the Gulf of Honduras on 9/28. By then, the W Caribbean season is already starting to get into full swing climowise. So, something to keep an eye on. Edit: A good number of 12Z EPS members active with this in W Caribbean 9/26-8.

Looking at the prior 10 years, the average number of hurricanes from storms born in Sept is only two. So, Sept of 2022 has already exceeded that mark with three. Of the last 10 years, only 2020 had more with four and 2022 still has another 12 days to go. Fiona's ACE is likely going to end up quite impressive.

Now a hurricane officially at 70 knots.

Much of the eastern half of PR is getting blasted with very heavy rain along with solid TS force winds. Fiona is quite possibly a hurricane now. Waiting on official confirmation.

The 18Z EPS 144 has fewer left outliers vs the 12Z EPS 150.