GaWx

The 12Z JMA (an inferior model for the tropics) hit E ME just after hour 210 (early 9/16) while still having SLP in the 950s. (The prior 12Z hit just E in New Brunswick on 9/16.) I'm mentioning it because it agrees with the 12Z Euro on location although it is ~9 hours faster.

Regarding the 12Z EPS, I count a total of ~9 US hits excluding operational through 240 hours with ~5 hitting ME (excluding operational), ~3 hitting MA, and 1 hitting NY. Plus a couple more probably will hit on this run after 240. So, ~18%+ US hits on the 12Z EPS not including the operational, which means likely at least on par with the 20% of the previously most active 0Z of today. Or ~20%+ already if including operational. The point is that the significant increase in hits of the last run was maintained on this new run (12Z).

If the 12Z Euro were to happen to verify closely, the location of the highest E coast tidal range, Eastport, ME, would be very heavily affected by surge. So, the timing of any potential landfall near there in relation to high and low tide would make a larger difference there than at other locations on the US E coast. On Sept 16 for example, the predicted high tides are near 19 feet (just after midnight and noon): https://www.usharbors.com/harbor/maine/eastport-me/tides/

Indeed, E ME 966 mb on 9/16 at 18Z

12Z Euro 144 a whopping 41 mb weaker (960) than 0Z 156 (919) and barely ESE of the 0Z

So, you're going likely only a moderate RONI peak?

So, the JMA had an ONI peak drop from 2.22 in last month's prog to ~2.05 in this new one. The Euro similarly dropped from 2.40 to ~2.25. The somewhat inferior CFS dropped even more sharply, from 2.11 to ~1.76. So, all three of these have dropped since last month (~0.15 to ~0.35). As a result, I'm lowering my ONI peak prediction from 2.2 to 2.1 and will continue to adjust as per what the model and other data shows. Of course, the RONI peak would be lower, probably near +1.6 to +1.7.

As mentioned, the 0Z EPS had 6 members with US hits (4 ME and 2 MA) just through 240, which was already the largest # of hits of any complete EPS run yet, and with the post 240 portion still not then out. The post 240 portion showed another 4 hits (3 MA and 1 ME meaning a total of 5 ME and 5 MA) for a full 0Z EPS total of 10 (20%), which doubles the previous run highest hit total of 5 (10%) that was from the run 24 hours earlier. Summary of EPS (0Z and 12Z) runs' CONUS hits: 0Z 9/7: 10 (20%) (9/15-18) (5 ME, 5 MA) 12Z 9/6: 3 (6%) (ME 9/15 & 9/17, MA 9/18) 0Z 9/6: 5 (10%) 12Z 9/5: 2 (4%) 0Z 9/5: 4 (8%) 12Z 9/4: 1 (2%) 0Z 9/4: 2 (4%)

The 0Z EPS' 6 (12%) CONUS hits is the highest yet, beating the 5 hits by the 0Z of 24 hours ago and that was for that full 15 day run. Four hit ME and two hit MA. And that's only through 240 as it appears a couple more will likely hit after 240. This is more evidence that the NE is not safe even though I still consider it a low chance. Nova Scotia and the area near Bermuda appear to get hit the hardest.

0Z Euro 240 slams into W Nova Scotia.

0Z Euro 180 is 250 miles NNW of the 12Z run and even a little N of the 0Z of yesterday.

0Z UKMET: stronger but similar track to 12Z run recurving near 70W. Initialized pretty well on position. HURRICANE LEE ANALYSED POSITION : 15.0N 47.0W ATCF IDENTIFIER : AL132023 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 0000UTC 07.09.2023 0 15.0N 47.0W 998 52 1200UTC 07.09.2023 12 15.9N 49.4W 994 48 0000UTC 08.09.2023 24 16.7N 51.8W 993 50 1200UTC 08.09.2023 36 17.5N 54.2W 993 56 0000UTC 09.09.2023 48 18.3N 56.3W 993 59 1200UTC 09.09.2023 60 19.2N 58.4W 994 57 0000UTC 10.09.2023 72 20.0N 60.0W 991 54 1200UTC 10.09.2023 84 20.9N 61.7W 989 57 0000UTC 11.09.2023 96 21.6N 63.0W 985 53 1200UTC 11.09.2023 108 22.3N 64.7W 979 51 0000UTC 12.09.2023 120 23.1N 66.1W 975 59 1200UTC 12.09.2023 132 23.6N 67.5W 973 63 0000UTC 13.09.2023 144 24.2N 68.6W 963 73 1200UTC 13.09.2023 156 24.8N 69.2W 957 84 0000UTC 14.09.2023 168 26.3N 69.9W 951 82

18Z Euro 72 is ~75 miles NE of the 12Z at 78

There's still a cold wake left by Franklin near and just W of Bermuda. Should it track there, hopefully this wake would weaken Lee some.

Probably. Is there a chance for Margot to move, say, WNW, and pump heights?

Last 6 EPS runs (0Z and 12Z only): # of members with CONUS H landfall 12Z 9/6: 3 (6%) (ME 9/15 & 9/17, MA 9/18) 0Z 9/6: 5 (10%) 12Z 9/5: 2 (4%) 0Z 9/5: 4 (8%) 12Z 9/4: 1 (2%) 0Z 9/4: 2 (4%) So, the latest run dropped from 10% to 6%. The chance remains low.

That makes sense. But is there an alternative possibility, that of potential Margot helping to pump up the ridge to its NW and then leading to an omega block that forces Lee into the NE like was the case with Sandy? (See my post above showing the omega block that affected Sandy). I'll repost the Sandy omega block image:

I agree that that's bad because it takes away from objectivity. But equally bad is doing the opposite. I strive for a happy medium of sorts.

Saying there's still a small chance for a NE hit isn't wish-casting. It's the truth because nobody can possibly know with certainty this far out that Lee won't hit there. Do I think it will hit there? No, due to strong odds imo that it won't. Will I say the NE is safe from a hit? No, because there's still a 20% or so chance imo for a hit somewhere in the NE though that % is continually adjusted up and down. Biases in forecasting, whether bullish or bearish, are common. My goal here is to try to be as objective as possible based on the model data and other facts like history/analogs, try to generate interesting forecasting discussions, etc. This storm isn't even going to come close to directly affecting me way down here barring something really crazy. Furthermore, I wouldn't want this coming anywhere close to here. On another note, I'd like to know whether or not Sandy is an analog to consider for potential forecasting difficulties regarding the NE US. I don't mean that this is necessarily going to be another storm with as big of an impact as Sandy had should it actually hit. I'm just wondering if the possibility of a left hook into the NE is being considered as a small possibility. Although the Euro did well a week out showing the hook as I recall, other models didn't. So, is this an analog to just consider or not? Opinions?

Are you talking about the US? If so, there are a couple of hits (NE US) in addition to some on SE Canada. The chance of a US hit remains low but there is a chance.

Just through 240, the 12Z EPS appears to be fairly similar to the 0Z. It has one H hit the ME/NB border on 9/15, one hit S Nova Scotia, several more aiming for the NE/SE Canada, and a few much further S including one H and 2 TS in the Bahamas. I'll check the entire run later when it comes out.

12Z Euro at 168 is ~200 miles SSE of the 0Z at 180.

The 12Z Euro at 132 is ~150 miles SSE of the 0Z at 144 and isn't quite as strong though it is still a beast.

The 12Z UKMET is similar to the 0Z and thus the ~200 mile E shift of today's 0Z vs yesterday's more ominous 12Z was maintained. Regardless, I maintain there's still a chance for the NE US to be hit albeit a small chance. When I say small, I mean something like 20%, which is nothing to take lightly as they're nowhere near safe at this point. Although the highest % of Euro ens members hitting the NE US so far (through today's 0Z run) is 10%, I'm still at double that due to how far out in time it still is. At 168, the 12Z UKMET has Lee ~250 miles NE of the SE Bahamas moving NNW: TROPICAL STORM LEE ANALYSED POSITION : 13.7N 44.8W ATCF IDENTIFIER : AL132023 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 06.09.2023 0 13.7N 44.8W 1003 43 0000UTC 07.09.2023 12 15.3N 46.6W 1002 43 1200UTC 07.09.2023 24 16.3N 49.3W 1000 41 0000UTC 08.09.2023 36 17.0N 51.8W 1000 40 1200UTC 08.09.2023 48 17.7N 54.6W 997 55 0000UTC 09.09.2023 60 18.3N 57.0W 997 52 1200UTC 09.09.2023 72 19.1N 59.3W 997 53 0000UTC 10.09.2023 84 19.7N 61.1W 997 55 1200UTC 10.09.2023 96 20.0N 63.1W 994 57 0000UTC 11.09.2023 108 20.6N 64.4W 994 53 1200UTC 11.09.2023 120 20.9N 65.6W 994 53 0000UTC 12.09.2023 132 21.7N 66.8W 991 56 1200UTC 12.09.2023 144 22.6N 67.3W 985 50 0000UTC 13.09.2023 156 23.4N 68.4W 978 52 1200UTC 13.09.2023 168 24.2N 68.9W 973 61