GaWx

The 12Z EPS has ~30% of the members become a H. A handful of them threaten the Leewards to Bermuda corridor 9/19-22. Another two of them hit near the NC/SC border 9/20-22. All fwiw.

Ldub in 5, 4, 3, 2, 1...

For the first time in seven runs, the 12Z UKMET doesn't make this a TC! Keep in mind that the UKMET was the first model to develop this into a TD. Is it now saying "psyche"?

The 0Z UKMET is the 6th in a row with genesis although it develops quite a bit later than the other runs: phantom alert or just delayed development, who knows? NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 132 HOURS FORECAST POSITION AT T+132 : 15.7N 43.0W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 12.09.2022 132 15.7N 43.0W 1011 25 0000UTC 13.09.2022 144 17.7N 45.7W 1011 29

Unlike the 12Z ICON, which appeared to be setting up for a recurve way out there based on a big upper low off the CONUS, the 0Z ICON has a very different H5 setup to its NW late in the run.

Regarding the newest lemon for the AEW modeled to emerge from Africa 9/7-8, at 240 hours the 12Z GFS/CMC have only a very weak surface reflection whereas the 12Z Euro has an organized though weak low moving westward. They are all in the general vicinity of the Leeward Islands suggesting that this may have to be dealt with somewhere in the western basin in ~10-15 days. Edit: The 12Z EPS is very active with this. What's worrisome is that a good number of members after moving WNW change headings to W near 45W (similar to the operational) ~9/13 and then head W with the accompanying steering high to the north from there through 9/16 to 55-60W in a potentially dangerous position.

The 12Z UKMET is the 5th run in a row to have a TC from what has become the newest E MDR lemon. The Sun 9/4 12Z run UKMET was the first major op model to have this as an actual TC and was soon followed up by others. Will the UKMET end up with kudos? Or will it fail (phantom)? We'll see later: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 90 HOURS FORECAST POSITION AT T+ 90 : 10.5N 30.8W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 10.09.2022 96 10.9N 31.7W 1010 26 0000UTC 11.09.2022 108 11.8N 35.2W 1010 28 1200UTC 11.09.2022 120 12.4N 38.2W 1009 30 0000UTC 12.09.2022 132 14.1N 40.8W 1007 35 1200UTC 12.09.2022 144 15.5N 43.8W 1006 36 --------------------------------------------------------------- For comparison, here was that first UKMET run picking it up, the Sun 9/4 12Z run: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 120 HOURS FORECAST POSITION AT T+120 : 9.8N 26.4W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 09.09.2022 120 9.8N 26.4W 1009 26 0000UTC 10.09.2022 132 10.6N 30.4W 1009 29 1200UTC 10.09.2022 144 11.4N 34.2W 1008 33

For the same AEW, the 0Z GEFS is by far the most active run yet with more than half the 31 members with hurricanes. About half of those recurve harmlessly, but the others threaten at least the Caribbean 9/15-17+ fwiw.

Regarding the AEW I've been discussing that will come off Africa in 24-48 hours: 1. The 0Z ICON has this again and a bit stronger as it gets down to 997 mb. Based on the end of the run's motion and the weakening high to the north, it appears to be fishing. 2. 0Z GFS has this as a hurricane in the MDR after hardly doing anything with it on previous runs. With it much stronger, it also looks to be fishing on this though the run isn't finished yet. 3. 0Z UKMET has genesis much earlier again, similar to the two runs prior to the last one: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 60 HOURS FORECAST POSITION AT T+ 60 : 9.5N 19.9W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 08.09.2022 60 9.5N 19.9W 1008 33 0000UTC 09.09.2022 72 10.6N 21.8W 1009 27 1200UTC 09.09.2022 84 10.7N 25.1W 1009 27 0000UTC 10.09.2022 96 10.8N 28.6W 1008 28 1200UTC 10.09.2022 108 11.3N 32.4W 1007 32 0000UTC 11.09.2022 120 11.9N 35.7W 1006 33 1200UTC 11.09.2022 132 12.8N 38.4W 1005 41 0000UTC 12.09.2022 144 14.2N 40.5W 1004 47 4. 0Z CMC is also doing more with this than the prior run though it appears like it will likely fish on this run.

Busan should be getting about the worst of it now.

The 12Z EPS looks a bit menacing with this AEW position at 240, especially considering the high to the north moving west with this. The highest concentration of members with surface lows is right where the 12Z Euro op is at 240. Note that a number of members that earlier in the run were moving WNW curl back to a westerly heading. That is a recipe to bring AEWs into the western basin. This run has ~40% of its members with surface lows from this AEW. The prior run had ~60%. So, a tick down fwiw.

1. The 12Z GEFS, like the previous two runs, has a good number of strong members from the AEW coming off 9/7-8 with 8 of 31 that become hurricanes. The timing is slightly slower and the mean position a bit NE of the prior two runs meaning less threat to the NE Caribbean. It looks like the 12Z GEFS control (assuming I'm looking at the right member) plunges down to 939 mb SW of Bermuda on 9/20! 2. The 12Z UKMET has it for the 3rd time albeit genesis is delayed til hour 144, meaning a 48 hour delay vs the prior two runs (phantom alert!) and still in a similarly pretty far south latitude in the MDR: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 144 HOURS FORECAST POSITION AT T+144 : 12.5N 40.6W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 11.09.2022 144 12.5N 40.6W 1010 26 3. Meanwhile, the 12Z Euro has this as a very weak low moving W to WNW at 21N, 57W at hour 240 as of 12Z on 9/15. If this were to be near reality and then develop, it would subsequently probably become a threat to the western basin near 9/18-9/20. You can see that the run slides a rather strong surface/H5 high westward to its north throughout the preceding 7 days keeping it from recurving early and instead taking it toward the western Atlantic. Is this just a phantom? I wouldn't bet against it, but we don't know yet. This is the AEW that @Floydbusterbriefly talks about in his latest video that he shows coming far west on the 6Z GEFS.

0Z UKMET is the 2nd run in a row with this far south latitude E MDR TC moving WNW. It comes off Africa ~Sep 7th and then forms into a TD on Sep 9th. The 0Z ICON has this as a weak low near 15N, 41W, moving WNW at hour 180 (12Z on 9/12). Keep in mind though that this ICON run also has a cat 4 Earl temporarily stuck under a ridge then moving WNW to NW near 68W: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 108 HOURS FORECAST POSITION AT T+108 : 10.9N 25.0W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 09.09.2022 108 10.9N 25.0W 1009 27 0000UTC 10.09.2022 120 11.1N 29.1W 1008 30 1200UTC 10.09.2022 132 11.6N 32.8W 1007 32 0000UTC 11.09.2022 144 12.5N 36.1W 1007 33 Edit: African satellite pics looking unimpressive plus considering the way the season has gone since Bonnie makes me think this is probably a phantom TD on the UKMET even though the UKMET is fairly conservative. Update for 0Z GEFS: Fwiw, the 0Z GEFS is the most active run with this AEW that comes off Africa within 60-72 hours. Some of these members (5 of 31) get into or near the E Caribbean as a H 9/15-16. It will be interesting to see what happens with Earl if this actually ends up an active AEW as Earl's indirect effects on steering would be significant.

I got 2" this morning (9/4) and am getting another dowsing now. The rainforest climo, which dominated July and August here after a very dry mid Nov-May, seems to want to continue. Despite a low tide having been as recently as 10PM, the rain I just got 11PM-midnight produced about as bad flooding of my street/yard as any this summer and quite possibly the worst. I'll have totals later (Edit: 2.02" putting me near 4.5" already this month) but this flooding was made worse by the 2" this morning as well as a very wet late August. My water table is sky high from all of the rain the last 66 days, nearly 30"! And only ~4" of this was from an organized tropical system, the precursor to Colin on July 1st. That makes this even more unusual.

Nope, I'm showing the stark contrast between August's shutout (0 ACE vs normal of 27 for a deficit of 27) and the much more active first half of September. 9/1-15 has a great shot at 40. It even has a decent shot at 50, which would be vs a 33 normal and thus a surplus of 17. No pretending here as I'm just posting the facts. Actually, I never forecasted this season to be active vs 1991-2022 climo like some, but rather forecasted an ACE of 120, which is near the 1991-2020 average. We'll see if it gets there. If 9/1-15 were to get 50, that would bring 2022 to 53 as of 9/15 vs a 1991-2020 average of 70. An active 9/16-10/15 could get it to over 100. The average for 9/16-10/15 is 37.

After posting that, I compared the 18Z EPS 132-144 tracks to the 12Z EPS 138-150 tracks. This suggests that the 18Z would very likely have had fewer, if any, threaten the US. So, it may be just another one of those fluky EPS runs like we had a couple of days ago.

Here we go again with the EPS. On the 12z, 5 of 51 (10%) hit the US as hurricanes 9/13-16 (2 FL 9/13 and 9/14), 2 hit NC (9/14 and 9/16), and 1 hits ME (9/14). Also, a few others are close. On the 18Z GFS, 2 of 31 (6%) hit the US as a H on 9/14 (1-NC, 1-VA). This is mainly for the record as it is just a longshot for a US hit as opposed to a concern at this time. However, it may be a bigger threat for the Canadian Maritimes. Also, Bermuda may need to watch this.

This is a new one on the 12Z UKMET fwiw, which is at a very low latitude moving WNW in the E MDR: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 120 HOURS FORECAST POSITION AT T+120 : 9.8N 26.4W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 09.09.2022 120 9.8N 26.4W 1009 26 0000UTC 10.09.2022 132 10.6N 30.4W 1009 29 1200UTC 10.09.2022 144 11.4N 34.2W 1008 33 Also, just looking at Danielle and Earl, alone, per the NHC progs and extending further out, ACE for just about every day through Sept 12 is likely to be above normal at least through then meaning at or above normal ACE days through a good portion of peak season. And this doesn't include any other TC that may develop. If Earl becomes a major (now forecasted), it alone will generate 4+ per day for those days, which would be at a minimum 160% of the highest ACE average for any day for 1991-2020, which is 2.5 (Sept 15th). Per 1991-2020 averages, Sep 1-15 average ACE is 33. 2022 could easily end up 40+ for Sep 1-15. That would be quite an impressive turnaround. If Earl were to become a major on 9/8 and remain that way for several days, a 50+ ACE for Sep 1-15 would not just be a remote possibility, especially considering what else may be out there. I'm still at 120 ACE for this season and 6 NS this month.

The switch has already flipped. From no TCs for 2 months to two at the same time. From no ACE for 2 months to near or above average ACE, which looks to likely continue at least into mid month. So, Derek can't be wrong from my perspective as he's already right.

The latest forecast has max winds at 90 knots when hitting SE S Korea/Busan near 0Z on Sept 6th. If this verifies, it would be near the worst on record there.

1. 1991-2020 ATL ACE daily climo peak period is 8/26-9/22. 2. Daily climo peaks of 1.7+: peak of peak period is 9/6-16 (bolded) with 9/15 the peak day at 2.5 - 8/26: 1.8 - 8/27: 1.7 - 8/28-29: 1.9 - 8/30: 1.8 - 8/31: 2.3 - 9/1-2: 2.4 - 9/3-4: 2.0 - 9/5: 1.9 - 9/6: 2.1 - 9/7: 2.0 - 9/8: 2.3 - 9/9-10: 2.4 - 9/11-12: 2.1 - 9/13: 2.4 - 9/14: 2.3 - 9/15: 2.5 peak day - 9/16: 2.3 - 9/17: 1.8 - 9/18: 1.7 - 9/19-20: 2.0 - 9/21: 1.7 - 9/22: 1.8 3. 9/3-7/22 should each day end up near 2.0 (near climo) Climo source: http://tropical.atmos.colostate.edu/Realtime/index.php?loc=northatlantic

Super typhoon Hinnamnor expected to land Busan on Tuesday Super typhoon Hinnamnor, the 11th cyclone for the year, is expected to land on Korea’s Busan and the southern coastal areas in South Gyeongsang Province on Tuesday, changing its course from what has originally been anticipated. By the time Hinnamnor lands on the Korean Peninsula between Monday evening and Tuesday morning, its central pressure is expected to reach between 940 and 950hPa. Typhoon Sarah in 1995 and Typhoon Maemi in 2003, both of which devastated the country, recorded central pressures of 951.5hPa and 954hPa, respectively. https://www.donga.com/en/article/all/20220903/3613183/1 Two worst to hit Busan: 1) 1959 Sarah: https://en.m.wikipedia.org/wiki/Typhoon_Sarah_(1959) 2) 2003 Maemi: https://en.m.wikipedia.org/wiki/Typhoon_Maemi

Now that it strengthened, 0Z UKMET has gone way to the right of recent runs. This suggests that had it stayed weak, it could have been more of a danger to hit the US.

The 18Z EPS suggests that the wider 12Z EPS spread was a bit of a fluke because the 18Z has gone back to a narrower spread with fewer US threats at 144 vs 12Z at 150.

But they also found it ~half a degree to the east. Probably a wash.