GaWx

The 0Z GEFS US hits went back down to 4 (13%) (9/16-8): 3 ME, 1 NY So, last 7 GEFS runs: 13%, 26%, 16%, 16%, 10%, 10%, 10%

Would you please provide a link to a table with the monthly 40 mb QBO? TIA

The 18Z GEFS has the most US hits yet by a good margin with 8 (26%) (9/16-7): 3 ME, 3 MA, 1 NY/RI, 1 NC Last 6 GEFS: 18Z 9/9 26% 12Z 9/9 16% 6Z 9/9 16% 0Z 9/9 10% 18Z 9/8 10% 12Z 9/8 10%

The last two UK runs have Lee get as far W as 67.7W. More importantly imo they both don't have the lowest SLP until 0Z on 9/16, when it gets down to the low 940s on both runs. That's quite low for the usually conservative UK and tells me that a significantly stronger storm than the current strength is quite possible even going out a good number of days from now. 12Z HURRICANE LEE ANALYSED POSITION : 19.8N 57.7W ATCF IDENTIFIER : AL132023 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 09.09.2023 0 19.8N 57.7W 955 79 0000UTC 10.09.2023 12 20.6N 58.9W 961 71 1200UTC 10.09.2023 24 21.4N 60.3W 957 80 0000UTC 11.09.2023 36 22.2N 61.4W 953 82 1200UTC 11.09.2023 48 22.8N 62.6W 953 84 0000UTC 12.09.2023 60 23.2N 64.0W 948 85 1200UTC 12.09.2023 72 23.5N 65.4W 949 90 0000UTC 13.09.2023 84 23.8N 66.3W 942 90 1200UTC 13.09.2023 96 24.1N 67.3W 953 74 0000UTC 14.09.2023 108 24.6N 67.5W 946 77 1200UTC 14.09.2023 120 25.8N 67.7W 952 76 0000UTC 15.09.2023 132 27.3N 67.3W 947 79 1200UTC 15.09.2023 144 28.8N 67.2W 944 81 0000UTC 16.09.2023 156 30.3N 66.7W 941 70 1200UTC 16.09.2023 168 32.2N 66.5W 949 68

Or other 12Zs, like the inferior JMA, which recurves sharply and never even gets close to Canada. Or the (inferior?) KMA, which skims NS and then hits Newfoundland. Or the ICON/CMC, which hit NS. Or the quite inferior NAVGEM, which heads toward Newfoundland. The Euro is the only one of these 7 op models that hits the NE and the only other run to do so was the 12Z of 9/7. But then again why go with any operational in particular? Why do we need a definite yes or no when neither is there this far out and instead why not just go with the idea that Lee bears watching for the continued small chance of a NE hit and a bigger chance for a Canada hit? This is a forecasting discussion. We have these discussions because of the uncertainty.

Looking at current SSTs and the NHC path, SSTs don't fall below 29C until after 120 hours. That's when the cooler Franklin wake would have a significant impact. So, until then, they're mainly 29-30C, plenty warm.

You and I know that nothing has changed due to one operational Euro run. Ensembles are the way to go and they've continued to suggest a low chance. They keep showing outliers run after run. Chance still remains low but nowhere near zero. I'm still near 10%.

12Z EPS has ~6 (12%) (9/17-19) US hits excluding operational with 3 ME and 3 MA. So, it has increased again though nowhere near as high as the 9/7 runs and hits are later on average. 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%)

I counted 5 (16%) US landfalls (9/15-17) on the 12Z GEFS with 3 ME, 1 MA, and 1 NY/RI. Last 5 GEFS: 16%, 16%, 10%, 10%, 10%

GEFS has been showing 10-16% US hits for the last 5+ runs. EPS has shown 6-24% the last 7 runs. So, it hasn't been anywhere near totally dismissed by these ensembles.

It was 963 mb as of last evening but then the recon from 2 hrs ago showed 956 mb. And then this showed 100 knts/still major 954 mb as of 12Z: AL, 13, 2023090912, , BEST, 0, 200N, 578W, 100, 954, HU

6Z GEFS: 5 (16%) US hits (3 ME, 1 NY, 1 NJ) (9/16-7) vs 3 on prior 3 runs. Just passing along facts. Use the info however one wishes. I still think the chance is low (~10%) but still not yet near zero. Still too far out with runs like this.

The 0Z EPS had another drop in US landfalls to the lowest of the last 5 runs: 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%)

Indeed, the Euro is jumping around so much run to run. It hit NS on the prior run. This run, like the one from 24 hours earlier misses all land through 240 but is more than 24 hours slower.

0Z Euro 192 300+ miles SSW of 12Z

Just like the prior two GEFS runs and the 12Z EPS, the 0Z GEFS has 10% of its members with US landfalls. The three occur 9/15-17 (1 ME, 1 MA, 1 NY). They're all big hits with them at 951, 952, and 964 mb. So, the NE US is still nowhere near in the clear, especially with a potential hit being as much as 9-10 days out, despite the chance of a hit being low. These similar outliers keep showing up.

0Z UK never gets W of 67.7W vs prior run's 70.1W. As a result this passes much closer to Bermuda vs where recent runs were aiming: HURRICANE LEE ANALYSED POSITION : 19.1N 55.8W ATCF IDENTIFIER : AL132023 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 0000UTC 09.09.2023 0 19.1N 55.8W 958 83 1200UTC 09.09.2023 12 20.3N 57.4W 966 77 0000UTC 10.09.2023 24 21.2N 58.8W 970 69 1200UTC 10.09.2023 36 21.9N 60.0W 970 62 0000UTC 11.09.2023 48 22.6N 61.1W 970 66 1200UTC 11.09.2023 60 23.2N 62.5W 968 69 0000UTC 12.09.2023 72 23.7N 63.6W 964 72 1200UTC 12.09.2023 84 23.9N 65.0W 957 80 0000UTC 13.09.2023 96 24.2N 65.9W 952 77 1200UTC 13.09.2023 108 24.5N 66.8W 948 81 0000UTC 14.09.2023 120 24.9N 67.2W 950 79 1200UTC 14.09.2023 132 25.9N 67.7W 951 79 0000UTC 15.09.2023 144 27.5N 67.3W 947 80 1200UTC 15.09.2023 156 29.5N 67.7W 946 79 0000UTC 16.09.2023 168 31.4N 67.5W 944 76

Recent SSTs:

10% (3) (ME, RI, NY) of the 18Z GEFS landfall in the US, the same % as the 12Z GEFS and EPS. I wonder whether or not the recent weakening will make much difference on future runs since they typically initialize as much weaker than reality.

Due to very strict building codes as well as the vast majority of Bermuda being elevated well above even major storm surge levels (I've been there and thus have seen it firsthand), I wouldn't even feel all that worried if I were stuck there during a hurricane. I'd actually feel safer there than where I live. Map of Bermuda showing hilly areas dominating: https://www.worldatlas.com/maps/bermuda

You're welcome. Yes, they're anomalies. So, a 15, for example, means +1.5. From the link below, "The SST anomalies are in tenths of a degree (times 10)." and "Thus for the first record: 1949 999 999 0 0 -1 -2 -6 -8 -10 -11 -13 -13 The anomalies for this year are negative, with a value of -13 indicated a cold equatorial Pacific SST anomaly of -1.3 Deg-C." https://data.coaps.fsu.edu/pub/JMA_SST_Index/Readme.txt

It looks like ~5 (10%) of the 12Z EPS members through hour 240 have a US landfall with all on ME. If there are no more after 240 (probably the case), that would mean a drop from the 14% US landfalls on the 0Z and the 24% on yesterday's 12Z, which had the most. So, assuming 10% is it for the 12z, here is the running EPS tally of US landfalls: 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%) Based on the trend of the latest two EPS runs as well as overall model consensus trends, I'm dropping the chance for a US landfall from 20% to 10% and with that mostly for ME. I won't go lower because it is still 10% on the 12Z EPS and the 12Z GEFS also has 10% (3 members hit 9/15-18 with one on each of ME, MA, and RI). To go lower than 10% with any potential hit still 7-10 days away along with the 10% of ensemble members having hits would seem premature.

Webb's tables, which sometimes get updated even for years going way back, are the best I've seen regarding 3.4 for pre-1950. Also, I use the JMA (see link below) as a secondary source for pre-1950 even though it uses a variation of Nino 3 instead of 3.4. The JMA similar to Webb has 1925-6 as only lower end strong. Per these two sources, I feel very comfortable calling 1877-8 a super and pretty comfortable calling 1888-9 a super. I see no other definitive super pre-1950 although 1896-7 and 1930-31 are pretty close per both Webb and JMA while 1902-3 is pretty close per Webb. JMA: https://data.coaps.fsu.edu/pub/JMA_SST_Index/jmasst1868-today.filter-5

Where are you seeing that 1925-6 was a super Nino? According to the Eric Webb table at the following link, the ONI maxed at just +1.5 (low end strong): https://www.webberweather.com/ensemble-oceanic-nino-index.html

I'm still near a 20% chance for a NE US landfall for now.