GaWx

12Z UKMET goes NW over far E PR and then moves WNW for short time followed by NW...so quite a shift E from prior run at PR! MET OFFICE TROPICAL CYCLONE GUIDANCE FOR NORTH-EAST PACIFIC AND ATLANTIC GLOBAL MODEL DATA TIME 1200UTC 17.09.2022 TROPICAL STORM FIONA ANALYSED POSITION : 16.3N 63.6W ATCF IDENTIFIER : AL072022 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 17.09.2022 0 16.3N 63.6W 1005 35 0000UTC 18.09.2022 12 17.2N 64.9W 1003 33 1200UTC 18.09.2022 24 18.4N 65.8W 1001 44 0000UTC 19.09.2022 36 19.0N 67.7W 999 45 1200UTC 19.09.2022 48 20.0N 68.6W 999 46 0000UTC 20.09.2022 60 21.4N 69.9W 996 53 1200UTC 20.09.2022 72 22.4N 70.5W 995 51 0000UTC 21.09.2022 84 23.9N 70.5W 987 57 1200UTC 21.09.2022 96 25.8N 70.0W 978 54 0000UTC 22.09.2022 108 27.8N 69.3W 969 63 1200UTC 22.09.2022 120 30.6N 68.6W 961 73 0000UTC 23.09.2022 132 33.9N 66.5W 953 84 1200UTC 23.09.2022 144 38.7N 61.4W 942 99

Is the 0Z EPS drunk? About 30% of the members landfall on the SE US coast after only 8% at 12Z! Also, fwiw since not a good model, the 0Z CFS hits FL and then skirts the coast up to NC. Earlier runs were OTS. And keep in mind the 12Z JMA's sharp left turn from 168 to 192.

Horrible flooding reported in Guadeloupe. Look out Virgin Islands and PR this weekend and DR Sunday. This has been a very wet storm. And it is going to slow down, a very lethal combination.

Today this looks less impressive as of DMIN although it is starting to refire convection near 11N, 30W. Still watching as quite a few ensemble members still keep this intact near the Caribbean.

A safe miss of the CONUS is easily the best bet on the 12Z EPS. However, fwiw, it has 6 of the 51 members (only 12%) hit the CONUS as a TS+: 2 ME, 1 SC, and 3 FL (2 far south and 1 Melbourne) that then go into the Gulf.

With regard to the CONUS, a safe recurve is clearly the best bet as of now. That has the support of the Euro, GFS suite, UKMET, and CMC. But on the 12Z JMA (slower) from 168 to 192, it gets blocked and turns west at least for a short time from a new high to its north. Also, fwiw, many of the 12Z CMC ensemble members (GEPS) hit the CONUS (2 in NE US, handful FL, and good number Gulf coast). The JMA and GEPS both bigtime suck vs the more credible Euro, GFS, and UKMET, of course. But I thought it was worth mentioning.

This only waned a little after I last posted about this near midday. Now, check it out as we start to head toward DMAX, which is still 5-6 hours away in the E MDR. Convection has again blossomed in a circular pattern and is centered on 11N, 24W. It looks even more impressive than it looked early today. This has the makings of a sleeper as the NHC doesn't mention this in the TWO.

Per NHC, Fiona dropped another 0.2 of latitude between the 5PM (AST) and 8PM positions, which is south of the NHC track. It is now down to 16.1N vs 16.6N at the 11AM position during a period in which it was forecasted to be at 16.6N now. So, it is now 35 miles south of where the 11AM track had it for now.

Headed for NC?

Happy Hour GFS is way west vs 12Z!

12Z EPS implies ~30% risk of a CONUS TS+ landfall based on ~15 of TS+ members landfalling there. Per NHC, Fiona lost 0.3 degrees of latitude the last 6 hours.

I think that is more likely a cat 1 H landfall at WPB on the 12Z Euro (near 990 mb). Look for the 12Z EPS mean to shift SW.

It appears per satellite loops that there is a circulation at 11N, 23W, moving west. Anyone else see this?

MET OFFICE TROPICAL CYCLONE GUIDANCE FOR NORTH-EAST PACIFIC AND ATLANTIC GLOBAL MODEL DATA TIME 1200UTC 15.09.2022 TROPICAL STORM FIONA ANALYSED POSITION : 16.3N 53.7W ATCF IDENTIFIER : AL072022 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 15.09.2022 0 16.3N 53.7W 1008 39 0000UTC 16.09.2022 12 16.5N 56.3W 1007 40 1200UTC 16.09.2022 24 16.7N 58.9W 1007 37 0000UTC 17.09.2022 36 17.0N 61.4W 1006 32 1200UTC 17.09.2022 48 17.4N 63.5W 1006 34 0000UTC 18.09.2022 60 18.1N 65.4W 1005 36 1200UTC 18.09.2022 72 17.8N 67.5W 1004 43 0000UTC 19.09.2022 84 19.2N 68.9W 1001 43 1200UTC 19.09.2022 96 19.9N 69.8W 997 56 0000UTC 20.09.2022 108 20.7N 71.2W 994 54 1200UTC 20.09.2022 120 21.3N 72.0W 996 51 0000UTC 21.09.2022 132 22.0N 72.2W 993 47 1200UTC 21.09.2022 144 23.1N 72.2W 990 48

11 AM NHC kept it at 16.6N (straight west since last advisory).

Per satellite loops, it at least appears to be moving ever so slightly south of due west vs the 5AM NHC's ever so slight north of due west. It may very well be as far south as 16.5 or 16.4 N now though sometimes the satellite suggested location doesn't match the actual due to tilt. If it is at 16.4-5 N, that would be slightly south (by ~15 miles) of the 5 AM track's implied position of 16.6-7 N now. If that's true (although 15 miles may not seem like much), that would imply a slight southward track adjustment at 11AM. Other opinions on a likely 11 AM track adjustment?

This shows a slight SW trend of the mean track from 0Z to 6Z EPS. I think there will be more SW adjustments eventually though not necessarily consistently from run to run.

The 6Z EPS has 75% of members at or south of the south coast of the Dominican Republic. Odds of a move into the Gulf are increasing imo (assuming it survives).

TROPICAL DEPRESSION FIONA ANALYSED POSITION : 16.4N 51.4W ATCF IDENTIFIER : AL072022 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 0000UTC 15.09.2022 0 16.4N 51.4W 1010 36 1200UTC 15.09.2022 12 16.4N 53.9W 1009 38 0000UTC 16.09.2022 24 16.7N 56.2W 1008 37 1200UTC 16.09.2022 36 17.0N 58.9W 1009 35 0000UTC 17.09.2022 48 17.5N 61.6W 1008 30 1200UTC 17.09.2022 60 17.8N 64.0W 1007 31 0000UTC 18.09.2022 72 18.0N 66.5W 1006 32 1200UTC 18.09.2022 84 18.6N 67.8W 1004 39 0000UTC 19.09.2022 96 18.8N 68.6W 1002 43 1200UTC 19.09.2022 108 19.8N 69.9W 996 53 0000UTC 20.09.2022 120 20.5N 71.2W 995 53 1200UTC 20.09.2022 132 21.1N 72.0W 996 51 0000UTC 21.09.2022 144 22.0N 72.2W 997 45

Followup: - The 12Z ICON makes this a H near 14N, 50W, and then takes it NW. - The 12Z JMA takes this westward to just E of LAs as a very weak low moving WNW at 192 hours. - The 12Z Euro is the 4th in a row that has a persistent surface low from the AEW just now leaving Africa. The prior three all hit the Lesser Antilles. This run has it just E of the LAs as of 168 moving W (Sept 21st) after which it moves W well into the Caribbean as a very weak low: Update for 12Z EPS: Those members at 240 which are located from NE of PR to the LAs to the MHs NE of the Leewards as well as those members S of PR and Hisp. in the Caribbean are from this AEW that's now just off Africa rather than from 96L. Some of those Caribbean members then go into the Gulf. Update: The 12Z UKMET has this: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 138 HOURS FORECAST POSITION AT T+138 : 12.9N 48.2W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 20.09.2022 144 13.2N 49.2W 1009 30

12Z UKMET TROPICAL DEPRESSION 96L ANALYSED POSITION : 16.5N 49.5W ATCF IDENTIFIER : AL962022 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 14.09.2022 0 16.5N 49.5W 1010 36 0000UTC 15.09.2022 12 16.5N 52.2W 1010 34 1200UTC 15.09.2022 24 16.3N 54.8W 1010 36 0000UTC 16.09.2022 36 16.7N 56.0W 1009 39 1200UTC 16.09.2022 48 16.7N 59.0W 1009 36 0000UTC 17.09.2022 60 17.5N 61.6W 1008 32 1200UTC 17.09.2022 72 17.8N 63.7W 1007 31 0000UTC 18.09.2022 84 18.4N 65.5W 1006 32 1200UTC 18.09.2022 96 18.5N 67.7W 1005 35 0000UTC 19.09.2022 108 19.4N 68.7W 1002 40 1200UTC 19.09.2022 120 20.6N 70.1W 999 52 0000UTC 20.09.2022 132 21.2N 71.5W 997 53 1200UTC 20.09.2022 144 22.0N 72.6W 998 48

While we're concentrating on Invest 96L for good reason, folks should probably at least keep one eye on an AEW that's coming off Africa in ~12 hours. It has been quite active over W Africa. Several models (Euro, ICON, CMC) are now taking this at least to 50W in the MDR. The last 3 Euro runs haven taken it to at least the Lesser Antilles. The latest Euro takes this to just SW of PR as a TS moving WNW at 240 hours (9/24).

Convectively, the IR satellite looks more impressive than either GFS or CMC IR simulation maps look. Also, it looks more impressive than 24 hours ago, which itself looked rather impressive, itself. Shear is pretty low and SSTs are warming as it moves westward. This is moving over a climo favored region for development in mid Sept in a non-El Nino season. Several third year cold ENSO analogs have had genesis within 51-57W between 9/13 and 9/20. Thus, I remain confident this will become a TC and it will probably become a TD before 60W. It doesn't matter much to me how the season has gone so far. That being said, the UKMET (0Z) once again does nothing with it: TROPICAL DEPRESSION 96L ANALYSED POSITION : 15.7N 47.3W ATCF IDENTIFIER : AL962022 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 0000UTC 14.09.2022 0 15.7N 47.3W 1011 24 1200UTC 14.09.2022 12 CEASED TRACKING

12z Euro looks to be taking a little bit further SW track based on 96 hours, when the very weak low center is 200 miles south of PR. Edit: At 192, it is in the W Caribbean with a strong high to its north. Upon further review, the 12Z Euro seems to be combining 96L with some energy coming from the SW Caribbean. Anyone notice this? So, I'll need to later look at the 6 hour maps to see exactly where 96L tracked. And upon even more review: Check out the 12z Euro 850 mb vorticity maps. If you look closely, the NE portion of the 240 hour Bahamas low actually is associated with vorticity that is still over Africa, not the low now just offshore Africa, and won't come off til hour 48! I mean this vorticity speeds like a racehorse across the MDR! This is pretty fascinating.

TWO remains 30%/40% but the wording seems slightly less bullish: Tropical Weather Outlook NWS National Hurricane Center Miami FL 200 PM EDT Tue Sep 13 2022 For the North Atlantic...Caribbean Sea and the Gulf of Mexico: 1. Central Tropical Atlantic: Showers and thunderstorms associated with a tropical wave located about 1000 miles east of the Lesser Antilles have changed little in organization since this morning. Although environmental conditions are only marginally conducive, some gradual development of this system is possible over the next few days. A tropical depression could form while the system moves westward to west-northwestward over the tropical Atlantic and approaches the Leeward Islands on Friday. * Formation chance through 48 hours...low...30 percent. * Formation chance through 5 days...medium...40 percent.