GaWx

Yeah, probably ST. The UKMET has a hybrid low form in the E GOM instead.

I’m leaning more to +1.6. Keep in mind that the Mon update is the avg of the week prior. The max of the month had approached 1.7 though, including on 9/13.

For the record per NHC, the core moved over far W NS and center is now over Bay of Fundy. So, officially no US center landfall in case anyone is wondering: Post-Tropical Cyclone Lee Discussion Number 46 NWS National Hurricane Center Miami FL AL132023 500 PM AST Sat Sep 16 2023 The core of Lee briefly moved across Long Island in Western Nova Scotia within the past hour or so. Satellite images and surface observations indicate that the center is now over the Bay of Fundy. Rain bands continue to spread across portions of Maine, New Brunswick, and Nova Scotia as seen in radar images. A pair of ASCAT passes from several ago showed that Lee remains very large, but the core winds have decreased below hurricane-force. Considering some undersampling of that data, the initial intensity was lowered to 60 kt on the 1800 UTC intermediate advisory. The forward motion of Lee is slower than earlier today as it moves near the west coast of Nova Scotia. However, the storm is expected to turn northeastward and accelerate late tonight and Sunday, bringing the system across the Canadian Maritimes. Little change was made to the previous NHC track forecast. FORECAST POSITIONS AND MAX WINDS INIT 16/2100Z 44.5N 66.1W 60 KT 70 MPH...POST-TROPICAL 12H 17/0600Z 46.5N 64.5W 50 KT 60 MPH...POST-TROP/EXTRATROP

For the record per NHC, the core moved over far W NS and center is now over Bay of Fundy. So, officially no US center landfall in case anyone is wondering: Post-Tropical Cyclone Lee Discussion Number 46 NWS National Hurricane Center Miami FL AL132023 500 PM AST Sat Sep 16 2023 The core of Lee briefly moved across Long Island in Western Nova Scotia within the past hour or so. Satellite images and surface observations indicate that the center is now over the Bay of Fundy. Rain bands continue to spread across portions of Maine, New Brunswick, and Nova Scotia as seen in radar images. A pair of ASCAT passes from several ago showed that Lee remains very large, but the core winds have decreased below hurricane-force. Considering some undersampling of that data, the initial intensity was lowered to 60 kt on the 1800 UTC intermediate advisory. The forward motion of Lee is slower than earlier today as it moves near the west coast of Nova Scotia. However, the storm is expected to turn northeastward and accelerate late tonight and Sunday, bringing the system across the Canadian Maritimes. Little change was made to the previous NHC track forecast. FORECAST POSITIONS AND MAX WINDS INIT 16/2100Z 44.5N 66.1W 60 KT 70 MPH...POST-TROPICAL 12H 17/0600Z 46.5N 64.5W 50 KT 60 MPH...POST-TROP/EXTRATROP

He also said Lee would restrengthen down to 920 mb and it got down only to ~946. He often swings for the fences. So, I recommend taking him with a big grain though that doesn't mean next season won't be very active. If this season gets to 150 ACE, does that mean a prediction of 300?

I agree with you on this 100%. I believe that rampant over-attributing actually backfires rather than helps educate the ignorant on AGW, which I like you acknowledge is real. This causes straw-men to be created. These straw-men then lead to AGW skeptics having increased doubt that AGW exists. Somewhat related to this is the sensationalism surrounding the 101F water temperature that was measured by a buoy in 5 foot deep water in July barely offshore S FL. Numerous media outlets reported on this 101F as if it were a legit world record SST and they still won't stop. First of all, that wasn't even the hottest ever at that buoy as it hit 102 last decade. But not only that, it more importantly wasn't even a legit SST in the normal sense. What the media didn't report was that the waters there are very shallow with a dark bottom that can be seen from above. That dark bottom absorbs extra heat. The tides have a large effect due to the shallowness. Also, that same buoy had a morning low SST of 91 and it cooled to 84F within just 2.5 days due to increased clouds/rainfall. Even Dr. Masters warned others that it isn't legit. Look at this chart: Did the media report that it cooled 17F within 2.5 days? Of course not. So, what happened is that many AGW skeptics were attacking the straw-man of the 101F water temp as not legit, which is true. But then they go a step further and use that to claim AGW isn't real, which is false. The low 90s SSTs at Key West much of this summer were legit and (near) record SSTs for there, and this lead to severe coral bleaching nearby. The low 90s were likely mainly due to AGW in combo with a very dry pattern. Without AGW, that same dry pattern may have resulted in only, say, upper 80s instead of low 90s. Thus, the coral wouldn't have suffered nearly as much. So, there was a legit problem around the Keys made much worse by AGW. The KW buoy isn't in super shallow water. Thus the low 90s were legit SSTs. But repeatedly talking about a non legit 101 SST hurts the recognition of the problem more than it helps because it sounds like BS. I'm concerned that there was AGW over-attribution regarding the Maui wildfires. Even IF AGW played a part, there was a whole lot more to this than AGW. It does seem that AGW has been used by some as a convenient excuse and it looks bad.

I think the slow (6-9 mph) movement for five straight days (9/9-13) was likely a factor in keeping it in check. Combined with its increasing size, Lee likely moved slowly enough to cool the SSTs just enough ahead of the center to keep it from getting back to a cat 4. But as it was, it was still a large H that grew even larger and was a MH for much of that period.

Whereas there hasn't at all been the typical reduction in ACE associated with El Niño, there has been a weak Bermuda High/WAR along with the usual tracks associated with it. As incredibly busy as it has been, there so far has been only one storm with a W or WNW heading W of 74W (Harold) and there are no others in sight! That is typical of a moderate or stronger El Niño:

Despite the noted tendency for the GFS to be too far right with recurving TCs, it was interestingly enough way too far LEFT with both of the 2022 Ian SE US landfalls and also too far left with last month's Idalia FL landfall. Thus I'm wondering if the GFS really still has a too far right bias for recurves and instead now has a net neutral or possibly even a left bias: 1. FL Ian landfall 1-4 days out: - GFS was still way up at Apalachee Bay just 68 hours from landfall (0Z 9/26 run) vs the actual Port Charlotte (PC) landfall point. That's a 200 mile error to the left at just 68 hours out! - At that point, UKMET was dead-on at PC and ICON was at Venice, only 25 miles from PC. - GFS wasn't close to PC until the 12Z 9/27 run, just 32 hours out. Until then it was too far left on all runs out going back at least several days: 2. SC Ian landfall 1-4 days out: - GFS was still way down at Hilton Head just 54 hours from landfall (12Z 9/28 run). That's 100 miles to the left of the actual track. - GFS wasn't close to the actual landfall location of Georgetown until the 12Z 9/29 run, just 30 hours out. Until then it was too far left on all runs out going back at least several days: 3. FL Idalia landfall: - GFS was on the left side of the model consensus for several days of runs before landfall and about as far left as any - Just 30 hours out with the 8/29 6Z run, the GFS was still 50 miles too far left of the actual landfall - The Euro and ICON were almost always to the right of the GFS (as well as much closer to the actual track), and the UKMET was usually to the right of the GFS.

9/14 18Z EPS had a mere two (4%) US landfalling members and they were on the far E end of ME. It's looking very good for no US landfall. 9/15 0Z UKMET into SW NS PM of 9/16

I saw this paper before. It may increase the chance for a multi-year Nino during 2025-9. A good hint of this is warm NW/cool SE in N America in DJF, rather typical of El Niño. Also, note the cold Scandinavia and Australia in winter. One of the reasons for the cool anomalies appears to be heavier than normal precip related if I'm recalling correctly as the volcano itself apparently favors net increased global warmth.

What are the implications of "huge amounts of water vapor" in NH polar cap as regards the most likely effects on E US winters over the next 5 years or so? Do you have any idea based on what experts are saying? If so, please answer this as objectively as possible. Based on you making a post about this, I'm assuming you think there are potentially significant implications. TIA

9/14 12Z: 11 (22%) 10 ME, 1 MA (CC) So, the 12Z EPS had an increase in ME along with one MA outlier, but this still suggests a high chance (78%) for no US landfall. So, I'm going with no US landfall.

OHC per this graph dropping back some more to <+1.2:

-Out of twelve 0Z models including the 4 tropical models and excluding the NAM, the only one showing a US landfall is the lowly JMA (central ME). And the JMA shifted away from Cape Cod since 12Z. How far off does this 0Z JMA, even after its significant NE shift, appear to be? It is to the left of all 51 members of the last three EPS runs ending with today's 6Z run: -Recent EPS Runs' US Landfalls: going down 9/14 6Z: 6 (12%) 6 ME 9/14 0Z: 7 (14%) 7 ME 9/13 18Z: 10 (20%) 10 ME 9/13 12Z: 14 (27%) 13 ME, 1 MA 9/13 6Z: 35 (69%) 27 ME, 6 MA, 2 RI 9/12 18Z: 36 (71%) 21 ME, 9 MA, 3 RI, 3 NY (LI)

0Z run landfalls: -Arpege: SW NS early 9/16 968 mb (faster and E shift vs 12Z's NB) -ICON: NB early 9/17 981 mb (similar to 12Z) -GFS: NB early 9/17 976 mb (similar to 12Z) -CMC: SW NS late 9/16 980 mb (slight W shift vs 12Z) -UKMET: SW NS late 9/16 970 mb (slight E shift vs 12Z) -JMA (inferior): C ME early 9/17 973 mb (NE shift vs 12Z, which crossed CC) -Euro: NB early 9/17 976 mb (similar to 12Z) -KMA: SW NS midday 9/16 ~960 mb (big E shift vs 12Z's E ME)

The NAM is a horrible model to use for the tropics. That being said, the JMA may not be all that much better and I still post about it.

Agreed. The past five days have averaged for NE US landfalls ~25-30% on the EPS and ~20% on the GEFS. So, under 25% for the two, combined. Also, the GEPS (considered inferior and thus not as closely followed) has had a significantly lower % than the GEFS. Many of those runs had no more than 1-2 hits (10% or lower). So, yes, the totality of the GEFS/EPS/GEPS suggested about a four times better chance of no US landfall vs a landfall. But of course, it is easy to hindsight. Next time may be different. Just going with the 1 out of 5 chance for a landfall, the next time may be one of those 20%. And we shouldn't forget that there still is a chance at a ME landfall with Lee.

A bit more than that for the ensemble runs. Yesterday's 18Z EPS was the peak with ~70% NE US landfalls with 30% (15 members) just for NE US excluding Maine. At least two other EPS runs since yesterday had ~50% landfalling in New England. The GEFS for NE US landfalls peaked at over 40% on one run three days ago and also had a run over 30% two days ago. But since yesterday, it has been mainly ~20% or less. Thus the EPS peaked after the GEFS backed down.

Indeed as expected, Aug of 2023 of ~29.7 is 2nd warmest for Nino 4 since 1950. So, that point should be emphasized. The current +1.3 in Nino 4 is pretty impressive. But OTOH beside the current strong Nino, the graph clearly shows that it's getting a good boost from more general warming. Since 1980, it has trended up ~1C. After taking that trend into account, the 29.7 is arguably less impressive than the 29.4 of 1987 and the 29.5 of 1994 and about on par with the 28.8 of 1982, the 29.25 of 1991, the 29.3 of 1997, and the 29.45 of 2002.

On OISST, Nino 3.4 (nearly +1.7) and Nino 4 (nearly +1.2) are at new highs while Nino 3 is about tied for the high (nearly +2.3). Nino 1+2 bounced back some (to nearly +2.9) as a correction as expected after its recent plunge.

UKMET has also done pretty well overall with the tropics for track (not intensity though). It was doing the best for Lee with the Euro second best as per graphs that were posted earlier. Also, it did great for Ian last year as regards both the FL and SC landfalls and I think it was pretty good for Idalia.

Did he drop his 920 mb peak restrengthening prediction yet? The lowest it got back down to was 946 mb per NHC advisories.