GaWx

18Z ICON/GFS a little faster and approach/hit W NS at 120 (Sep 16th afternoon). They're both in mid to high 960s for SLP while just offshore. It appears to be down to a TS then though a very large one with wide reaching effects. So, the exact landfall location would probably not matter as much as it would for a more compact storm. For the probably few who care, the 12Z JMA hits Eastport, ME, at 144 (Sep 17th AM).

For trend following purposes for those who like following these and for the record here are EPS 0Z/12Z run US landfalls, which have resulted in three runs in a row with 20%+. That's a significant %, but OTOH the rising has stopped for now and it is still well under 50%: 9/11 12Z: ~11 (22%): ~9 ME, 2 MA 9/11 0Z: ~12 (24%): ~9 ME, 1 MA, 1 RI, 1 NY 9/10 12Z: 10 (20%): 6 ME, 3 MA, 1 RI 9/10 0Z: 3 (6%): 1 ME, 2 MA 9/9 12Z: 6 (12%) 9/17-19 (3 ME, 3 MA) 9/9 0Z: 3 (6%) 9/17 (3 ME) 9/8 12Z: 5 (10%) 9/15-18 (5 ME) 9/8 0Z: 7 (14%) 9/15-17 (6 ME, 1 NY) 9/7 12Z: 12 (24%) 9/15-19 (7 ME, 3 MA, 1 NY, 1 NJ) 9/7 0Z: 10 (20%) 9/15-18 (5 ME, 5 MA) 9/6 12Z: 3 (6%) 9/15-18 (2 ME, 1 MA) 9/6 0Z: 5 (10%) 9/5 12Z: 2 (4%) 9/5 0Z: 4 (8%) 9/4 12Z: 1 (2%) 9/4 0Z: 2 (4%) Aside: 12Z op hit W NS at 969 mb very early on 9/17

This is very good news from the standpoint of the prospects of reducing the dominance of the SE ridge as well as reducing the frequency and amplitude of the MC MJO phases. Hopefully it lasts! Then again, we have the -PDO and +AMO that aren't usually on the side of those who favor colder winters, especially down here in the SE.

Yeah, thank goodness the high tides won't be as high as those of the full moon and perigee of Sep 2, when they peaked at 21.5 feet at Eastport. However, after relatively low high tides Sep 8-10, the new moon will soon after lead to a secondary peak of 18.8 feet Sep 16-17 meaning a fairly average high tide for there. Hopefully the worst of the surge would be close to low tide: https://www.usharbors.com/harbor/maine/eastport-me/tides/?tide=2023-09#monthly-tide-chart

Thus the timing of any potential landfall vs high/low tide would be extra crucial vs other areas. Related to this, Eastport, ME, has the largest average daily tidal range on the US east coast at ~19 feet.

This new JMA ONI peak is ~+2.05 (for NDJ). That is cooler than the +2.22 NDJ from the August run. That means that the JMA (~0.17), Euro (~0.15), and the (inferior) CFS (~0.35) have all cooled since a month ago. OTOH, the BoM remained the same.

The W Pacific/MC warm pool anomaly, which has been a major factor as regards a warming influence over the last five winters in the E US as exhibited by a frequent strong SE ridge as well as the MJO being on the warmer (right) side of the diagram more often than on the colder (left) side, has cooled significantly vs 12 months ago. I may post more details on this later. What are the implications for the upcoming E US winter? Does this mean a good chance at a colder one to at least close to normal? Of course, we still have the very warm Atlantic (+AMO) though increased tropical activity has helped cool it some.

For record/trend following purposes, GEFS US initial landfalls: 12Z had a drop to 6 (19%) (3 ME, 2 MA, 1 NJ/NYC) with only one strong left hooking member. Almost all of the rest have initial landfall into NS or via the Bay of Fundy into NB. Last 13 GEFS runs: 19%, 32%, 29%, 26%, 42%, 10%, 13%, 26%, 16%, 16%, 10%, 10%, 10%

12Z UKMET: -slight left shift (vs 0Z's W NS landfall) with skim of W NS at 975 mb followed by move into Bay of Fundy and early 9/17 NB landfall -slightly stronger peak of 940 mb Tues night HURRICANE LEE ANALYSED POSITION : 23.1N 63.2W ATCF IDENTIFIER : AL132023 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 11.09.2023 0 23.1N 63.2W 944 89 0000UTC 12.09.2023 12 23.7N 64.6W 949 86 1200UTC 12.09.2023 24 24.2N 65.6W 948 83 0000UTC 13.09.2023 36 25.0N 66.5W 940 91 1200UTC 13.09.2023 48 26.1N 67.2W 940 85 0000UTC 14.09.2023 60 27.7N 67.3W 943 81 1200UTC 14.09.2023 72 29.8N 67.8W 946 75 0000UTC 15.09.2023 84 32.0N 67.7W 945 76 1200UTC 15.09.2023 96 34.5N 67.0W 952 66 0000UTC 16.09.2023 108 37.9N 66.1W 955 78 1200UTC 16.09.2023 120 41.4N 66.5W 960 60 0000UTC 17.09.2023 132 44.2N 66.3W 975 42 1200UTC 17.09.2023 144 47.5N 64.8W 991 37 0000UTC 18.09.2023 156 49.7N 62.6W 996 35 1200UTC 18.09.2023 168 50.2N 60.0W 1003 26

For record/trend following purposes, GEFS US landfalls: last 4 runs 26-42% US landfalls 6Z GEFS: ~10 (32%) ~6 ME, 2 MA, 2 RI Last 12 GEFS runs: 32%, 29%, 26%, 42%, 10%, 13%, 26%, 16%, 16%, 10%, 10%, 10%

Trying to keep this going as long as countable in order to follow trend and for record: EPS 0Z/12Z US landfalls: two 20%+ in a row 9/11 0Z: ~12 (24%): ~9 ME, 1 MA, 1 RI, 1 NY 9/10 12Z: 10 (20%): 6 ME, 3 MA, 1 RI 9/10 0Z: 3 (6%): 1 ME, 2 MA 9/9 12Z: 6 (12%) 9/17-19 (3 ME, 3 MA) 9/9 0Z: 3 (6%) 9/17 (3 ME) 9/8 12Z: 5 (10%) 9/15-18 (5 ME) 9/8 0Z: 7 (14%) 9/15-17 (6 ME, 1 NY) 9/7 12Z: 12 (24%) 9/15-19 (7 ME, 3 MA, 1 NY, 1 NJ) 9/7 0Z: 10 (20%) 9/15-18 (5 ME, 5 MA) 9/6 12Z: 3 (6%) 9/15-18 (2 ME, 1 MA) 9/6 0Z: 5 (10%) 9/5 12Z: 2 (4%) 9/5 0Z: 4 (8%) 9/4 12Z: 1 (2%) 9/4 0Z: 2 (4%)

For the record 6Z GFS landfall E ME 9/17

0Z Euro: Very similar to the 0Z GFS, this has a NB landfall 9/17 near 977 mb.

This GEFS (0Z) doesn't have 5 sharp left turning members going into RI/LI like the 18Z, but it still has one going into E LI. There's ~3 into MA and ~5 into ME. So, a total of 9 (29%). So, this is the 3rd active run in a row for the NE. Last 11 GEFS runs: 29%, 26%, 42%, 10%, 13%, 26%, 16%, 16%, 10%, 10%, 10%

1. The 0Z GFS has a move into the Bay of Fundy followed by a landfall on New Brunswick on 9/17. 2. The 0Z ICON and CMC both hit Nova Scotia (9/16 and 9/17, respectively). 3. The 0Z UKMET hits Nova Scotia on 9/17: HURRICANE LEE ANALYSED POSITION : 22.3N 61.9W ATCF IDENTIFIER : AL132023 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 0000UTC 11.09.2023 0 22.3N 61.9W 952 77 1200UTC 11.09.2023 12 23.2N 63.0W 954 86 0000UTC 12.09.2023 24 23.7N 64.4W 949 87 1200UTC 12.09.2023 36 24.1N 65.6W 949 86 0000UTC 13.09.2023 48 24.7N 66.4W 948 79 1200UTC 13.09.2023 60 25.7N 67.2W 948 75 0000UTC 14.09.2023 72 27.0N 67.3W 945 80 1200UTC 14.09.2023 84 28.8N 67.9W 948 74 0000UTC 15.09.2023 96 30.3N 67.9W 947 70 1200UTC 15.09.2023 108 32.0N 67.5W 951 68 0000UTC 16.09.2023 120 34.7N 66.5W 954 69 1200UTC 16.09.2023 132 38.0N 66.1W 961 65 0000UTC 17.09.2023 144 40.6N 66.7W 964 57 1200UTC 17.09.2023 156 42.3N 66.5W 974 46 0000UTC 18.09.2023 168 44.7N 63.9W 989 41

Indeed, five (16%) hooked left enough to landfall anywhere from near the RI/MA border W to almost NYC while there were fewer ME landfalls. That's quite a change.

The 18Z GEFS US landfalls went back down some from the ~13 of the 12Z to 8 (26%): 3 ME, 3 RI, 2 NY So, last 10 GEFS runs: 26%, 42%, 10%, 13%, 26%, 16%, 16%, 10%, 10%, 10%

Based on the significant increase in 12Z EPS and 12Z/18Z GEFS US landfalls together with the threat largely being within only one week now meaning model trends are increasingly statistically significant, I'm increasing my US landfall chance from 10% back up to the 20% I was at originally.

EPS US landfalls: 9/10 12Z: 10 (20%): 6 ME, 3 MA, 1 RI 9/10 0Z: 3 (6%): 1 ME, 2 MA 9/9 12Z: 6 (12%) 9/17-19 (3 ME, 3 MA) 9/9 0Z: 3 (6%) 9/17 (3 ME) 9/8 12Z: 5 (10%) 9/15-18 (5 ME) 9/8 0Z: 7 (14%) 9/15-17 (6 ME, 1 NY) 9/7 12Z: 12 (24%) 9/15-19 (7 ME, 3 MA, 1 NY, 1 NJ) 9/7 0Z: 10 (20%) 9/15-18 (5 ME, 5 MA) 9/6 12Z: 3 (6%) 9/15-18 (2 ME, 1 MA) 9/6 0Z: 5 (10%) 9/5 12Z: 2 (4%) 9/5 0Z: 4 (8%) 9/4 12Z: 1 (2%) 9/4 0Z: 2 (4%)

12Z JMA landfalls W NS. KMA hits C to E NS.

How accurate are those two tropical models for track vs the main global models?

After a drop on the 0Z/6Z runs, the 12Z GEFS clearly has the most US landfalls of any GEFS run yet, which had been 8 (18Z of yesterday). There are so many close together in ME that it is hard to count them! I'm estimating 13 US hits (42%) with ~8 in ME, 4 in MA, and 1 in NJ. I'd say a minimum of 12 (39%)(7 ME). I try not to double count. So, a MA landfall followed by ME counts as only a MA landfall for me. Edit: it may be as many as 14 hits because ME may have as many as 9!

The 12Z UK sped up considerably and is just off C NS at 168 hours at 970 mb. Its SLP peak of 944 mb isn't til 8PM EDT on Thu (9/14). Based on the often conservative UKMET still getting the SLP to fall back to 944 mb, I feel that a second peak as low as ~935 mb is a reasonable possibility, but I still feel JB's 920 mb is very likely too low due to progged too slow movement likely leading to too much cooling ahead of the center to support pressures that low. We'll see: HURRICANE LEE ANALYSED POSITION : 21.6N 60.8W ATCF IDENTIFIER : AL132023 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 10.09.2023 0 21.6N 60.8W 954 79 0000UTC 11.09.2023 12 22.2N 61.9W 961 74 1200UTC 11.09.2023 24 23.1N 63.5W 964 74 0000UTC 12.09.2023 36 23.6N 64.9W 957 76 1200UTC 12.09.2023 48 23.9N 66.3W 952 75 0000UTC 13.09.2023 60 24.5N 67.2W 951 75 1200UTC 13.09.2023 72 25.3N 67.9W 952 71 0000UTC 14.09.2023 84 26.4N 68.2W 949 78 1200UTC 14.09.2023 96 28.0N 68.4W 949 77 0000UTC 15.09.2023 108 29.8N 68.3W 944 76 1200UTC 15.09.2023 120 32.0N 67.9W 948 77 0000UTC 16.09.2023 132 35.0N 66.8W 950 72 1200UTC 16.09.2023 144 38.5N 66.1W 956 73 0000UTC 17.09.2023 156 41.4N 65.6W 959 53 1200UTC 17.09.2023 168 44.1N 63.8W 970 47

"Anything is possible" as you just said I agree with 100%. That is my main point. It is still early.

OHC: Aug to peak warming: -1991-2 1.49 -2009-10 0.96 -1997-8 0.77 -2002-3 0.67 -2018-9 0.66 With August of 2023 at +1.09, these five suggest a peak of +1.75+ and two of them even suggest a peak of +2.0+. My point is that I feel that it is too early to have a lot of confidence that the OHC won't make it to +1.75+ for this event. Also, consider how fast it rewarmed from late July to late August.