GaWx

Along with the 12 runs of the UKMET, ICON, and GFS, the 12Z Euro has its strongest run yet with this with it landfalling in Nicaragua as a strong TS at 120. Also, the 12Z CMC has a H as earlier mentioned.

1. 12Z GFS is the strongest yet as of hour 144. Also, the 12Z ICON has it the strongest yet of any of its runs. The 12Z CMC has another strong run. 2. The 12Z UKMET is the first of its runs with TCG from this, at hour 138 east of Nicaragua moving westward: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 138 HOURS FORECAST POSITION AT T+138 : 12.8N 80.8W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 10.10.2022 144 12.8N 81.8W 1006 27

Actually per early October climo, much less November climo, the CONUS is more often than not threatened as per what I posted yesterday about October 1-10 geneses 1851-2021 from 50W westward to the W Caribbean: "So, out of the grand total of 51 looked at, only 9 (18%) buried themselves into CA while 33 (65%) or 3.6 times as many hit the CONUS (majority as a H). The main point is that IF there is going to be TCG from this, we shouldn't assume at this very early stage that it would bury itself in CA regardless of what the model consensus may suggest. The models of course may still be right as 18% is not a tiny percent and I'm not saying to bet on a US hit, but history says don't bet the farm on a CA burial this early especially due to the lack of model reliability that far out!"

With 91L (along with possibly 92L) being an increased threat to form and considering that 5 TCs formed after the peak date of the season climowise (Sept 14th+) resulting in one of the most active 2nd halves of September on record, this is already highly debatable imho. What exactly is meant by a backloaded season?

A clearcut uptick on the 18Z EPS vs the 12Z

Now I'll look at how these models did for the SC landfall for Ian by looking at the 9/26 12Z through 9/30 0Z runs: * = goes offshore FL 12Z 9/26: CMC just E of Columbus, GA GFS Albany, GA Euro Columbus, GA Icon SE GA *UKMET CHS 0Z 9/27: CMC 100 miles NW of Gainesville, FL GFS Gainesville, FL Euro: JAX *ICON: SAV *UKMET: CHS 12Z 9/27: CMC just SW of JAX GFS JAX *Euro just S of SAV *iCON Beaufort *UKMET CHS 0Z 9/28: CMC JAX *GFS HHI *Euro HHI *ICON CHS *UKMET 20 mi NE of CHS 12Z 9/28: *CMC Beaufort *GFS HHI *Euro HHI *ICON CHS *UKMET just SW of MB 0Z 9/29: *CMC CHS *GFS CHS *Euro Beaufort *ICON Beaufort *UKMET G'town 12Z 9/29: *CMC G'town *GFS G'town *Euro CHS *ICON CHS *UKMET 25 mi NE of G'town 0Z 9/30: *CMC MB *GFS G'town *Euro CHS *ICON CHS *UKMET G'town Based on the above, I'm giving these grades for the four days of runs preceding the SC Ian landfall: CMC D GFS C- Euro C- ICON B UKMET A

We're still far enough out for climo/history to be a somewhat useful tool to consider. I looked at all TC geneses Oct 1-10 since 1851. I focused on the CONUS. Before I give the track stats, here's the overall picture via the map for 1851-2015 tracks for geneses Oct 1-10: https://www.nhc.noaa.gov/climo/images/oct_1_10.png Here are the stats: First, I looked at geneses in the central to western Caribbean. I counted 44. Out of these 44, 31 or 70% later landfalled on the CONUS. Only 7 (16%) buried themselves into CA and only 5 (11%) recurved E of the CONUS. There was one (2%) that dissipated in the GOM. - 21 of these 31 landfalls hit in FL and 6 hit in LA - 19 of these 31 landfalls hit as a H - 5 of these 19 H landfalls hit as a MH - 3 of these 31 landfalls were during the eight 3rd year cold ENSO analog seasons: - Isabel of 1985: hit FL/GA border as a TS - #5 of 1910: hit SW FL as a H - #5 of 1894: hit FL Panhandle as a H Second, I looked at the 7 geneses between the LAs and 50W that moved westward well into the Caribbean: - 2 of those 7 (29%) landfalled on the CONUS: one was Hazel of 1954 as a MH at the SC/NC border and the other was #6 of 1879 that hit the FL Panhandle as a TS - 2 of those 7 (29%) buried themselves into CA - 2 recurved barely east of the CONUS and 1 dissipated in the Caribbean So, out of the grand total of 51 looked at, only 9 (18%) buried themselves into CA while 33 (65%) or 3.6 times as many hit the CONUS (majority as a H). The main point is that IF there is going to be TCG from this, we shouldn't assume at this very early stage that it would bury itself in CA regardless of what the model consensus may suggest. The models of course may still be right as 18% is not a tiny percent and I'm not saying to bet on a US hit, but history says don't bet the farm on a CA burial this early especially due to the lack of model reliability that far out! To look at it in another way: had today's models been available, how many of the 42 TCs that didn't get buried in CA would have shown burial in CA at this early stage?

I had a whopping ~10" of rainfall Sept 1-10 leading to a water table so high that my AC condensation drainage stopped at least twice temporarily. Then I had ~nothing Sept 11-27, which was much needed! Finally, Ian gave me a thankfully modest 0.75" Sept 28-9, which got me to ~10.75" for the full month. So, although a third very wet month in a row, Sept. was very lopsided. So, I've had 4.75" of rainfall associated with TCs so far this season with 4" from the precursor to Colin on July 1st and 0.75" from Ian Sept. 28-9.

Thanks, ice. The 12Z EPS, though its mean is not nearly as active as the 12Z GEFS, did have a slight increase vs the 0Z EPS with several members having hurricanes vs none that I could see on the 0Z. More than likely, the Euro suite is underdone imho on the chances of this ending up as a strong TC by the W Caribbean although the GEFS could easily be overdone in the E Caribbean especially.

Indeed, outflow is already looking strong! The series of NHC climo maps showing the history of tracks for ten day genesis periods going back to 1851 is often a good tool to keep in the back of one's mind to try to help in forecasting discussions like this. The link below is to geneses during OCT 1-10, which would more than likely be the period to cover this one should it form. It suggests that the best chances to form would be either early (mainly between 50W and the LAs) or later in the Caribbean west of 70W (assuming it gets there). Since that link goes only to 2015, I'll point out that a whopping four TCs from just the last six seasons had genesis during OCT 1-10 in the W Caribbean: -Nate of 2017 -Michael of 2018 -Delta and Gamma of 2020 https://www.nhc.noaa.gov/climo/images/oct_1_10.png

Indeed, this is by far the strongest the CMC has had this. @Iceresistance recently started a thread about this wave:

The 12Z UKMET, like its prior runs, has no TC genesis formally noted. But as I said, it is often conservative with TCG and thus often misses genesis. If it ever shows TCG for this, that would be noteworthy to me. Meanwhile, the 12Z CMC fwiw has a hurricane in the central and western Caribbean. This is by far its strongest run with this so far. Even the worst models sometimes give worthy hints. *Edit: The 12Z GEFS as measured by both the mean precipitation and the individual members looks to me to be about the most active GEFS run yet in and near the eastern Caribbean.

This MDR wave ranks up with the precursors to Bonnie, Fiona, and Ian as regards the amount of MDR convection and it appears to have some organization. Thus I think its chances of resulting in a TC at some point are rather high though predicting later destinations (IF TCG occurs at some point) whether CA, CONUS, both, and/or other places (including a sharp recurve east of the CONUS with or without landfall elsewhere) is quite a challenge to say the least at this very early pre-TC stage. Just think about how difficult Ian was to predict just two days out from FL as a very strong hurricane! My favorite model of late, the UKMET, currently doesn't have TC genesis from this at 0Z though it is often conservative as regards genesis. I'll be looking to see whether the 12Z as well as future runs do the same. Fwiw, the 12Z GFS at hour 48 (near 54W in the MDR) along with the 6Z are the two most active runs of that model with this at that location. So, its subtle trend suggests it may be just now starting to catch onto it.

Who are you referring to in saying "we all"?

Looking back to the 0Z 9/25 runs at where the models had FL landfalls: 0Z 9/25: ICON Venice CMC Cedar Key GFS Destin Euro Sarasota UKMET Port Charlotte 12Z 9/25: ICON Sarasota CMC Apalachee Bay GFS Apalachee Bay Euro Tampa UKMET Venice 0Z 9/26: ICON Venice CMC Apalachee Bay GFS Apalachee Bay Euro Cedar Key UKMET Port Charlotte 12Z 9/26: ICON Tampa CMC Apalachicola GFS Tampa Euro Big Bend UKMET Port Charlotte 0Z 9/27: ICON Venice CMC Big Bend GFS Sarasota Euro Venice UKMET just N of Ft Myers 12Z 9/27: ICON Port Charlotte CMC Tampa GFS just N of Port Charlotte Euro Port Charlotte UKMET 20 miles S of Ft. Myers 0Z 9/28: ICON 15 miles S of Port Charlotte CMC Venice GFS Port Charlotte Euro Port Charlotte UKMET Port Charlotte My grades on FL landfall only (i.e., excluding SC landfall) for 9/25-8 runs: UKMET A- ICON B Euro C- GFS D CMC F

Our highest winds were only near 40 mph (in a couple of gusts) and we got only 0.75" of rain. There were virtually no power outages thank goodness. We got hit much harder by the precursor to Colin on July 1st, which gave us 4" of rain within 3 hours and some flooding. That center was much closer to us as it passed within only ~30 miles to the E and SE. All in all, we were quite fortunate with Ian.

Absolutely correct, thankfully! That was what the UKMET had been suggesting since the 12Z 9/26 run with no runs since then closer than Charleston for landfall even while the Euro and GFS continued to have landfalls in this area for several days afterward. Our highest winds were only near 40 mph (in a couple of gusts) and we got only 0.75" of rain. There were virtually no power outages thank goodness. We got hit much harder by the precursor to Colin on July 1st, which gave us 4" of rain within 3 hours and some flooding. That center was much closer to us as it passed within only ~30 miles to the E and SE.

000 WTNT34 KNHC 302043 TCPAT4 BULLETIN Post-Tropical Cyclone Ian Advisory Number 33 NWS National Hurricane Center Miami FL AL092022 500 PM EDT Fri Sep 30 2022 ...IAN BECOMES POST-TROPICAL BUT THE DANGEROUS STORM SURGE, FLASH FLOODING AND HIGH WIND THREAT CONTINUES... SUMMARY OF 500 PM EDT...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...33.9N 79.2W ABOUT 20 MI...35 KM NW OF MYRTLE BEACH SOUTH CAROLINA MAXIMUM SUSTAINED WINDS...70 MPH...110 KM/H PRESENT MOVEMENT...N OR 350 DEGREES AT 15 MPH...24 KM/H MINIMUM CENTRAL PRESSURE...982 MB...29.00 INCHES

000 WTNT34 KNHC 302043 TCPAT4 BULLETIN Post-Tropical Cyclone Ian Advisory Number 33 NWS National Hurricane Center Miami FL AL092022 500 PM EDT Fri Sep 30 2022 ...IAN BECOMES POST-TROPICAL BUT THE DANGEROUS STORM SURGE, FLASH FLOODING AND HIGH WIND THREAT CONTINUES... SUMMARY OF 500 PM EDT...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...33.9N 79.2W ABOUT 20 MI...35 KM NW OF MYRTLE BEACH SOUTH CAROLINA MAXIMUM SUSTAINED WINDS...70 MPH...110 KM/H PRESENT MOVEMENT...N OR 350 DEGREES AT 15 MPH...24 KM/H MINIMUM CENTRAL PRESSURE...982 MB...29.00 INCHES

Conway, SC, data suggests center passing just east? They're at 33.8N, 79.0. Note the north wind: 30 Sep 4:15 pm 68 66 94 N 13G24 1.25 Lt Rain OVC006 28.96 981.7 28.99 0.05 30 Sep 3:55 pm 66 64 94 N 21G32 2.00 Hvy Rain OVC008 28.98 982.4 29.01 0.20 Edit: And now at 4:45 PM, a WNW wind as the center apparently passes just to its north: 30 Sep 4:35 pm 66 66 100 WNW 9 1.00 Lt Rain OVC004 28.98 982.4 29.01 0.06

Conway, SC, data suggests center passing just east? They're at 33.8N, 79.0. Note the north wind: 30 Sep 4:15 pm 68 66 94 N 13G24 1.25 Lt Rain OVC006 28.96 981.7 28.99 0.05 30 Sep 3:55 pm 66 64 94 N 21G32 2.00 Hvy Rain OVC008 28.98 982.4 29.01 0.20 Edit: And now at 4:45 PM, a WNW wind as the center apparently passes just to its north: 30 Sep 4:35 pm 66 66 100 WNW 9 1.00 Lt Rain OVC004 28.98 982.4 29.01 0.06

Georgetown and about one hour later than when Josh declared landfall 20 miles to the SW makes much more sense and is consistent with the Georgetown obs I was seeing and posting

Georgetown makes much more sense as opposed to McClellanville. I did misquote the NHC's 2 PM update in my prior post saying hours til landfall when it had not quite made landfall. Apologies for that.

Thanks for the clarification. And now the NHC just said that it is hours from landfall. Makes much more sense.

Winds are now strong from the NW at Georgetown with SLP falling even more rapidly. It doesn't jibe with what Josh and Dr Knabb said about landfall already occurring.