GaWx

I found several more including Arthur of early July of 2014 with mesoscale complex origin in the GOM and Cindy of early July of 1959 (not El Niño), which formed from a nontropical low along a cold front off FL. So, for the SE so far: -Arthur 2014: early July developing weak Nino cat 2 into NC -Gaston 2004: late Aug weak Niño cat 1 into SC -Diana of 1984: early to mid Sep incoming Nina cat 2 into NC -Cindy of 1959: early Jul neutral ENSO cat 1 into SC -Yankee Hurricane of 1935: formed from nontropical low E of Bermuda Oct 30 that hit SE FL as a cat 2 H Nov 4th! Warm neutral ENSO -Storm #5 of 1913: early Oct formed from nontropical low off NE US and hit SC as cat 1/developing Nino -Storm #2 of 1898: late Aug cold neutral into GA cat 1 *Edited to add several more including Yankee Hurricane of 1935 (based on link below) and storm #5 of 1913 So, a TC that is purely nontropical in origin has resulted in a landfalling H on the SE US coast ~every 18 years on average over the last 125 years. The strongest landfalls were the three cat 2 hits, Arthur of 2014, Diana of 1984, and the Yankee H of 1935. Landfalls: 3 SC, 2 NC, 1 GA, 1 FL My educated guess based on recollection is that TS landfalls on the SE coast from nontropical origins have occurred a good bit more often than the once/18 years of H landfalls. But that’s intuitive because it typically takes a good bit of time for transition to tropical and there often isn’t a lot of time over water with them developing close to home. Edit: I was able to confirm a much higher frequency of SE TS landfalls vs H landfalls from a non-tropical origin: 12 in 73 years or ~1 every 6 years on average. So, chances of a nontropical originating TC landfalling on the SE US as a TS are ~3 times higher than that for a H: 2022: Colin 2021: Danny 2015: Ana 2007: Gabrielle 2002: Kyle 1981: Bret 1976: Dottie 1967: Doria 1965: #9 1962: #2 1960: Brenda 1952: #3 https://en.m.wikipedia.org/wiki/1935_Yankee_hurricane

Thank you. Indeed, Gaston (what you meant) of late August of 2004, in this case during a weak El Niño, joins Diana and late Aug of 1898 as a nontropical origin TC that then moved into the SE US as an H. Looking to see if I find more. Bob of 1991 was nontropical that hit the NE as a H. But I was looking for those that hit NC south.

This only quite vaguely resembles 1984 (Diana), which originated from the tail end energy on a rather strong cold front going offshore/nontropical which quickly became tropical. But 1984 was an extremely rare storm (100+ year storm?) and it occurred two weeks earlier during heart of the season. I don’t look for anything like that of course and this could easily turn out to be no big deal other than a good rainfall producer for some areas. However, in the extreme, this could be a STD/STS that becomes a TC (especially if it then moves NE offshore). Regardless, it is an interesting situation due to uncertainty. Edit: late August of 1898 may have been somewhat similar to 1984 that also became a hurricane that came back into the SE coast. Neither 1898 nor 1984 was during El Niño by the way. I’ll look to see if I can find more. But those are two of the most extreme cases off the top of my head. This is more or less a potential “ridge over troubled waters” setup where a rather strong surface high to the north provides lower level convergence to the south, which leads to lift and then the formation of a sfc low.

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.