GaWx

0Z UKMET is a little SSE of the 12Z, but it weakens it at hour 24 and doesn't bring it back like it did on the 12Z: TROPICAL DEPRESSION 91L ANALYSED POSITION : 15.1N 50.0W ATCF IDENTIFIER : AL912022 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 0000UTC 31.08.2022 0 15.1N 50.0W 1008 26 1200UTC 31.08.2022 12 15.3N 50.8W 1009 25 0000UTC 01.09.2022 24 CEASED TRACKING

This latest area update for 2022 shows the most dramatic change in two months. In comparing to the 2007-21 average for the date, 2022 has dropped all of the way down to +280K vs the +470 just eight days ago. This is the lowest it has been in relation to the prior 15 year mean since way back on July 10th: Recap of current area vs avg. of last 15 years as of: 6/15/22: +70K 6/16/22: +120K 6/20/22: +240K 6/22/22: +140K 6/29/22: -140K 7/1/22: +70K 7/10/22: +250K 7/12/22: +370K 7/16/22: +330K 7/20/22: +360K 7/23/22: +480K 7/26/22: +460K 7/30/22: +440K 8/7/22: +320K 8/10/22: +390K 8/13/22: +330K 8/16/22: +390K 8/18/22: +460K 8/21/22: +470K 8/29/22: +280K

Regarding ENSO, it was a slightly cold neutral season that followed a very slightly warm neutral. So, it isn't an ENSO analog or close to being one. I have no idea why it had no August NS. Although it had an ACE of only very roughly 12 as of 9/1, it ended up hyperactive in terms of ACE with a 189, which was the highest since 1950. The next season stronger than 1961 wasn't til 1995.

Good question. Going back to 1850 using Eric Webb's ONI chart, it didn't. However, I was able to find a 4 year period of cold ENSO, 1872-5 with 1875 at cold neutral. So, 1875 is the closest to it. Most cases of 3rd year La Nina went to El Nino the next year.

The 12Z UKMET is a bit SW of its 0Z position as of hour 96, when it is at 19.3N, 62.4W. This compares to the 0Z UKMET at 108, when it was 20.4N, 61.6W. Then the 12Z UKMET at hour 108 "ceases tracking" it as a TC: TROPICAL DEPRESSION 91L ANALYSED POSITION : 14.8N 48.3W ATCF IDENTIFIER : AL912022 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 30.08.2022 0 14.8N 48.3W 1009 25 0000UTC 31.08.2022 12 15.6N 49.4W 1009 24 1200UTC 31.08.2022 24 15.8N 50.6W 1008 26 0000UTC 01.09.2022 36 16.3N 51.8W 1008 25 1200UTC 01.09.2022 48 17.5N 53.9W 1007 27 0000UTC 02.09.2022 60 18.0N 55.8W 1007 28 1200UTC 02.09.2022 72 18.9N 57.9W 1007 31 0000UTC 03.09.2022 84 19.1N 60.5W 1008 31 1200UTC 03.09.2022 96 19.3N 62.4W 1009 29 0000UTC 04.09.2022 108 CEASED TRACKING Then, it brings it back at hour 138 as a "New tropical cyclone" when it has it at 21.0N, 70.1W, moving WNW, which is quite a bit WSW of the 0Z run's position for then: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 138 HOURS FORECAST POSITION AT T+138 : 21.0N 70.1W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 05.09.2022 144 21.6N 71.3W 1010 24 So, the actual 18Z position of today, which is 14.8N, 49.1W, compares to these two points in the 12Z UKMET, which are for both 6 hours earlier and 6 hours later: 1200UTC 30.08.2022 0 14.8N 48.3W 1009 25 0000UTC 31.08.2022 12 15.6N 49.4W 1009 24 Using interpolation, the actual 18Z position is 0.4 S and 0.25 W of the 12Z UKMET 18Z forecast point, which is ~45 miles SSW of the 12Z UKMET estimated position.

MET OFFICE TROPICAL CYCLONE GUIDANCE FOR NORTH-EAST PACIFIC AND ATLANTIC GLOBAL MODEL DATA TIME 0000UTC 30.08.2022 TROPICAL DEPRESSION 91L ANALYSED POSITION : 14.2N 48.0W ATCF IDENTIFIER : AL912022 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 0000UTC 30.08.2022 0 14.2N 48.0W 1009 25 1200UTC 30.08.2022 12 14.8N 48.7W 1009 24 0000UTC 31.08.2022 24 15.4N 49.6W 1008 23 1200UTC 31.08.2022 36 15.8N 50.6W 1008 26 0000UTC 01.09.2022 48 16.7N 51.6W 1008 25 1200UTC 01.09.2022 60 17.8N 53.4W 1007 27 0000UTC 02.09.2022 72 18.7N 54.7W 1007 28 1200UTC 02.09.2022 84 19.9N 57.7W 1006 36 0000UTC 03.09.2022 96 20.0N 59.5W 1007 35 1200UTC 03.09.2022 108 20.4N 61.6W 1008 31 0000UTC 04.09.2022 120 20.5N 63.4W 1008 29 1200UTC 04.09.2022 132 21.4N 65.0W 1009 28 0000UTC 05.09.2022 144 22.0N 67.3W 1008 27

There are 8 3rd year cold ENSO analogs that I've identified. As of 8/29, here are the four of these 8 analogs with lowest ACE: - 1874: 3 storms (1 H and 2 TS); rough guess of ACE 12; full season ACE 47; remaining 5 storms included 3 Hs, 2 with high impact (Bermuda, FL Big Bend, GA/SC/NC coasts, Jamaica) - 1956: 4 storms (1 MH, 1 H, and 2 TS); rough guess of ACE 32; full season ACE 54; remaining storms 8 including 2 Hs, one with high impact (FL Panhandle) - 1917: 2 storms (2 TS); rough guess of ACE 6; full season ACE 61; remaining two storms were MHs, one of which had high impact (Jamaica, W Cuba, FL Panhandle) - 1910: 2 storms (2 TS); rough guess of ACE 1; full season ACE 64....remaining three storms were Hs (one MH), two of which had high impact (Greater Antilles, SW FL, S TX) So, ACEwise as of 8/29, 2022's mere 3 is most similar to 1910 and 1917 of these ENSO analogs. Note that the Gulf coast of FL was hit all four seasons by a H: 9/24 (H), 9/27 (H), 9/28 (MH), 10/17 (MH) Regarding the other four 3rd year cold ENSO analogs, here was the impact on Gulf coast of FL: 9/2 (H), 9/17 (TS), 9/22 (TS), 9/25 (H), 10/8 (H), 10/23 (MH), 11/21 (H) Thus, I continue to feel that the Gulf coast of FL has an above normal threat this season and the highest threat of any land area. The lack of activity to this point is pretty much irrelevant as one can see by the dates the Gulf coast of FL was hit. Source of ENSO data is Eric Webb: https://www.webberweather.com/ensemble-oceanic-nino-index.html

Yeah, I see that whereas the 18Z GEFS avoids FL, it did bring a few members closer to NC north. Regardless, yes, it is still too early to assume anywhere near safe OTS from the US despite trends in that direction vs the prior few days since there's still no TC/tight center to track. If the southern part of the were to take over, then all bets might be off because it may then head to Cuba, which could then turn right into FL or other areas.

12Z UKMET: 132 hour position is a bit NE of 0Z UKMET at 144; at 144 12Z is at 22.8 N, 65.0 W with NW movement: TROPICAL DEPRESSION 91L ANALYSED POSITION : 14.3N 47.2W ATCF IDENTIFIER : AL912022 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 29.08.2022 0 14.3N 47.2W 1009 26 0000UTC 30.08.2022 12 14.2N 48.7W 1010 26 1200UTC 30.08.2022 24 14.9N 48.8W 1009 25 0000UTC 31.08.2022 36 15.3N 49.9W 1008 24 1200UTC 31.08.2022 48 15.7N 50.9W 1008 26 0000UTC 01.09.2022 60 16.5N 51.8W 1008 26 1200UTC 01.09.2022 72 17.1N 53.7W 1007 28 0000UTC 02.09.2022 84 18.1N 55.2W 1006 28 1200UTC 02.09.2022 96 19.3N 58.1W 1006 36 0000UTC 03.09.2022 108 19.7N 59.7W 1006 38 1200UTC 03.09.2022 120 20.7N 61.7W 1007 38 0000UTC 04.09.2022 132 21.4N 63.3W 1006 34 1200UTC 04.09.2022 144 22.8N 65.0W 1006 36 The 12Z ICON at 168 is quite a bit east of the 0Z ICON at 180, a sign of reduced threat from that model at least for now. Since the ICON had been showing about the most dangerous looking solutions for the US, this 12Z run shift is very good news, especially for FL. The 12Z GFS and CMC remain safely away from the US, but they both continue to threaten Bermuda. The consensus of non-Euro 12Z models is thankfully to stay safely away from the US but that could change over the next few days if movement is further west than models are showing. Thus, it is still too early to make a call with high confidence, especially since there's still no TC center to track and the system remains messy, even though the model trends are clearly good news for now for the US though not for Bermuda.

1. I received 0.10" yesterday (8/28) bringing me to 10.05" mtd. 2. I'm now getting more generous rainfall this morning (8/29) from thunderstorms embedded in a larger area of rain centered just offshore moving northward. Totals will be posted later. Likely will exceed 1". Edit: 3. I've been getting hit hard with very heavy rain at times along with some big pretty closeby CTG bolts from thunderstorms over the last hour or so (very late 8/29-early 8/30) as a result of a trough in the area. The combined total for this and this morning's likely 1"+ is going to be big and add to this already very wet month! I think it is ~3" but will verify tomorrow. Edit: I'm calling the total for 8/29-30 right at 3".

1. 0Z GFS no phantom H and yet this still recurves OTS from US. 2. Only ~10% of members from last 3 GEFS runs hit FL with a TC. 3. 0Z UKMET: TROPICAL DEPRESSION 91L ANALYSED POSITION : 14.1N 45.7W ATCF IDENTIFIER : AL912022 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 0000UTC 29.08.2022 0 14.1N 45.7W 1010 28 1200UTC 29.08.2022 12 13.9N 47.4W 1010 26 0000UTC 30.08.2022 24 14.2N 49.1W 1010 24 1200UTC 30.08.2022 36 13.7N 50.0W 1010 24 0000UTC 31.08.2022 48 14.2N 50.2W 1008 23 1200UTC 31.08.2022 60 15.2N 50.9W 1009 25 0000UTC 01.09.2022 72 15.8N 52.5W 1008 25 1200UTC 01.09.2022 84 16.9N 54.4W 1007 28 0000UTC 02.09.2022 96 17.6N 56.5W 1007 26 1200UTC 02.09.2022 108 18.9N 58.5W 1006 29 0000UTC 03.09.2022 120 19.3N 60.9W 1006 35 1200UTC 03.09.2022 132 20.0N 62.8W 1007 36 0000UTC 04.09.2022 144 20.8N 64.3W 1006 38

Convection popping back some as we approach DMAX.

Eight third year cold ENSO seasons: 1874, 1894, 1910, 1917, 1956, 1975, 1985, 2000 Source: Eric Webb https://www.webberweather.com/ensemble-oceanic-nino-index.html

Based on many of the EPS members also slowing down nearby at 240 hours with similar H5 and then mainly recurving safely offshore the US once resuming movement after 240, I agree with you that the storm would very likely have done what you said (safely OTS) had the 12Z Euro gone past 240 hours. You can also kind of tell by looking over N America at H5/sfc at 240. But this is merely speculation on what's already very speculative, the 240 hour position on an operational run. Things will surely change quite a bit over the next few days even though as of this moment staying OTS has a slight advantage imho.

Third year La Niña/cold neutral seasons have had a tendency to be quite a bit weaker than their respective prior seasons and many other La Niña seasons.

12Z UKMET: TROPICAL DEPRESSION 91L ANALYSED POSITION : 13.9N 44.3W ATCF IDENTIFIER : AL912022 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 28.08.2022 0 13.9N 44.3W 1009 35 0000UTC 29.08.2022 12 14.1N 45.0W 1010 30 1200UTC 29.08.2022 24 14.0N 46.9W 1010 27 0000UTC 30.08.2022 36 14.0N 47.6W 1009 27 1200UTC 30.08.2022 48 14.6N 48.3W 1008 26 0000UTC 31.08.2022 60 14.7N 49.2W 1008 25 1200UTC 31.08.2022 72 15.5N 50.6W 1008 26 0000UTC 01.09.2022 84 16.1N 52.1W 1007 27 1200UTC 01.09.2022 96 17.0N 54.1W 1007 28 0000UTC 02.09.2022 108 17.8N 55.9W 1005 27 1200UTC 02.09.2022 120 18.6N 58.4W 1005 29 0000UTC 03.09.2022 132 19.6N 60.7W 1004 36 1200UTC 03.09.2022 144 20.3N 62.9W 1003 36

Thanks for posting this. Even during the current very active era, the norm has been no majors on August 28th: - For the 27 seasons 1995-2021, only 6 (22%) had a MH on August 28th. The last one was in 2016. - Even for just the 10 La Nina Augusts back to 1995, there were still only 3 (30%) that had a MH in the Atlantic basin on August 28th (2016, 2010, and 1999).

Genesis is when the disturbance or invest is classified a depression. So yes, metrics for the cyclone count towards date of genesis for archival purposes officially so I tend to follow that. What about time zone for a new day? 0Z (GMT) or some other way or other time zone?

Count, tropical cyclone days (TCD), accumulated cyclone energy (ACE) and pressure accumulated cyclone energy (PACE) are officially binned within the scientific community by month of genesis. So, are you saying you'd count a TC genesis on, say, August 31st, that doesn't strengthen to a TD til, say, Sept 1st an August storm like I would? The reason I've decided to do it this way is because the NHC seasonal archives list a storm's start date as the date it first became a TD. Different strokes for different folks. There's no right or wrong way imho. Also, if I want to get technical, I could add to this discussion whether or not to use GMT 0Z as the cutoff time for a new day. I think using GMT is reasonable. Opinions about this?

There's no credibility to lose. There hasn't been any in 20+ years of posting going back to Isabel and before. That being said, ldub is looking incredibly lucky for August and it would be funny if the weak season call ends up right despite no credible scientific reasoning backing the prediction. There was one weak year that the same person won in a season contest I ran naturally due to eternal bearishness. On a related note, keep in mind that a TD that forms in August that then becomes a TS in Sept. is counted by some including me as an August, not Sept., storm due to going by month of TC genesis.

I got some rain this evening but don't have the measurement yet. Edit: .04" on 8/25. Also, got 0.20" on 8/26.

FYI: 1997, 1941, 1929, El Nino. 1961 the only non-E Nino of the 4 years listed.

12Z Euro looks active throughout the 6-10 within the MDR with 2 TCs moving pretty much westbound. There are two TSs at 240. The one then approaching the Virgin Islands is the one producing the lemon now just coming off Africa. Regarding the further east TC, just about all of the 12Z model runs have a vigorous AEW moving off Africa at 144, including the typically conservative UKMET that I posted earlier.

The 12z GFS forecasted shear anomaly averaged over the next 5 days shows above average shear Africa to Lesser Antilles and below average shear Caribbean before it increases there mid to late next week. So, based on this shear anomaly forecast, fwiw, the E Caribbean may be more vulnerable to a TC genesis than normal through early next week and the W Caribbean til about mid next week.