GaWx

Thanks. Wow, your reduction of RONI peak (tri) to +2.4 to +2.6 is a good bit below my latest RONI prog of ~+2.8 and is only slightly, if any, above the record of +2.4 from 1982-3! That would be way below some still current model progs of +3.3 to +3.5 for tri RONI! They’re likely going to bust way too high as it looks now. Your latest progged ONI tri peak of only +2.7 to +2.9 compares to some ONI tri peaks still near +4.0! Ray and all, check out the following large cooling adjustments on the CFSv2 for RONI monthlies: 7/22-31: Aug was +2.35 7/26-8/4: Aug fell to +1.9; Sep +3.0 8/5-14: Sep fell to +2.85; Oct +3.65; Nov +3.75 8/15-24: Sep fell even more to +2.5; Oct fell to +3.3; Nov fell to +3.5 The trend is clearly down.

0Z UKMET: doesn’t quite get it to Dolly strength but still has it as a TD although this run then weakens it while moving rapidly WNW in the MDR followed by a reformation 2 days later moving W much more slowly toward the SE Bahamas:NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 48 HOURSFORECAST POSITION AT T+ 48 : 12.4N 33.9WLEAD CENTRAL MAXIMUM WINDVERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)-------------- ---- -------- ------------- -------------0000UTC 27.08.2026 48 12.4N 33.9W 1010 281200UTC 27.08.2026 60 13.0N 37.8W 1009 300000UTC 28.08.2026 72 13.2N 42.0W 1009 311200UTC 28.08.2026 84 14.1N 46.7W 1010 320000UTC 29.08.2026 96 CEASED TRACKINGNEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 150 HOURSFORECAST POSITION AT T+150 : 20.3N 67.0WLEAD CENTRAL MAXIMUM WINDVERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)-------------- ---- -------- ------------- -------------1200UTC 31.08.2026 156 21.0N 68.4W 1010 340000UTC 01.09.2026 168 20.9N 70.6W 1009 32

Thanks for pointing this out, Mitch. Very interesting for sure! Check this excellent video from met. Travis Roberts just out a few hours ago. Within it, he talks about the initial flattening out (RONI, the top of your 2 graphs) that wasn’t there before, the same thing you pointed out! Also, check out how flat Aug has been on CDAS since the 5th! I mean that’s almost flat as a pancake type flat. Keep in mind that several models had forecasted a record breaking warming for just one month (for any month) of ~1C in August!

A severe thunderstorm went over my home ~3:10-25PM per radar. I’m out of town and thus couldn’t witness it. I think this is the first sig. rain there in a good while.

^This is now Invest 96L and it’s up to 30%/60% in the TWO.

^For the same TW now emerging from Africa:12Z UKMET vs 0Z: similar rapid WNW track through MDR though 2-3 mb stronger starting near 50W. As it leaves MDR and slows down, it strengthens notably to mid-level TS at the end of the run while still moving WNW on heading in direction of SE Bahamas though still 300+ miles from there. Remains a significant SW outlier, which could be due to a SW bias that it sometimes exhibits with weak systems:NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 54 HOURSFORECAST POSITION AT T+ 54 : 11.6N 31.9WLEAD CENTRAL MAXIMUM WINDVERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)-------------- ---- -------- ------------- -------------0000UTC 27.08.2026 60 12.1N 33.5W 1007 301200UTC 27.08.2026 72 12.3N 37.6W 1007 340000UTC 28.08.2026 84 13.2N 41.6W 1008 341200UTC 28.08.2026 96 14.0N 46.3W 1009 350000UTC 29.08.2026 108 14.9N 50.9W 1009 331200UTC 29.08.2026 120 16.5N 55.4W 1010 340000UTC 30.08.2026 132 17.5N 59.1W 1009 331200UTC 30.08.2026 144 18.9N 62.5W 1009 350000UTC 31.08.2026 156 19.6N 65.2W 1008 341200UTC 31.08.2026 168 20.2N 67.8W 1004 52

The very warm NW Pacific continues to drive a solid -PDO. It would be nice if that would diminish in intensity and allow a PDO increase. Strong El Niño forcing tends to favor a +PDO looking well back in history. Actually from 1877-8 through 1957-8, all 11 strong ones had a +PDO DJF. However, 1965-6 and 1972-3 were neutral. Then the 4 strong ones 1982-3 through 1997-8 went back to +PDO followed by a neutral 2009-10. 2015-6 went back to +PDO followed by 2023-4 being the first on record with a -PDO and a strong one at that! Being that August of 2026 will end up most likely 2nd strongest pre strong Nino Aug -PDO with even a slight chance at the strongest -PDO pre-strong Nino Aug, the chances of a +PDO this winter are low. Hopefully it would rise to neutral PDO and we don’t get the 2nd strong Nino winter -PDO in a row.Full tally for 20 strong El Niño events since 1877-8:-16 (80%) +PDO - 3 (15%) neutral PDO- 1 (5%) -PDOPDO data: https://www.ncei.noaa.gov/pub/data/cmb/ersst/v5/v6/index/ersst.v6.pdo.dat

Based on model consensus suggesting higher than normal pressures at Tahiti likely dominating the 7 days or so, I don’t think the consistently strong -SOI dailies will return at least until early Sept. We could even have some +SOI dailies til then.

A daily peak of +3.3 on OISST seems reasonable to me as it would be consistent with a monthly peak of +3.0 and a trimonthly peak of +2.8. The dailies could even peak near +3.5 for that matter and still be consistent based on the volatility of the dailies.

Thanks, Ray. Are these for trimonthly peaks or monthly peaks?

Check out how much cooler is August on the BoM RONI vs 2 weeks earlier: Two weeks ago Aug was +2.6 and Aug had been +2.6 to +2.7 on EVERY weekly run going all the way back to the early June run! Last and this week Aug cooled substantially to only +2.15! I've been following this carefully every BoM run since April 11th. EVERY month May through Aug has ended up ~0.4 cooler and Apr ended up 0.6 cooler than what the BoM had been stubbornly predicting for weeks on end early month and before for each of these nearby months without fail! This tells me with good confidence that Sep won’t end up even close to the +3.0 to +3.1 that it has been progging on EVERY run for Sep back to the June 13th run. (This is the same kind of strong warm bias that it had for the ‘23 Nino.) Thus I’m predicting that Sept will end up no warmer than +2.7 and it may end up as cool as only +2.4. What does this portend for the Nov peak? The BoM has been progging an ~+3.5 Nov peak since the July 25th run. So, it appears it likely has finally about peaked in its progs. Therefore, based on Apr-Aug BoM runs, I’m now predicting that the actual monthly RONI peak (in or near Nov) will only be ~+3.0 with a trimonthly peak only ~+2.8. That +2.8 trimonthly would still be a record warm RONI going back to 1950 beating 1982’s +2.4. So, it would still be historic for sure. But it wouldn’t be nearly as warm as the ~+3.3-3.5 trimonthly RONI peak of many runs of various models. Edit: OISST charts are telling us that this El Niño hasn’t been warming nearly as rapidly in August as had been progged by model consensus. Remember those record rapid 30 day warmings in Aug on the model consensus that I’ve posted about many times? That simply ain’t happening folks. The ground truth doesn’t lie. Does this look like rapid warming in Aug? It looks more like rather ordinary modest paced warming at best to me:

The NOAA weekly SSTa’s have been ~unchanged the last 2 weeks in all Nino regions except there has been 0.3 of cooling in Nino 4. This Nino 4 cooling jibes well with this OISST Nino 4 graph: They kept 3.4 at +1.8, which continues to be ~0.4 cooler than what this OISST has been suggesting:

Thanks for posting these. I see these are based on just one run, 8/22/26 at 0Z, as opposed to being based on a mean of multiple runs. To compare, the 3 day/12 run means on Tropical Tidbits and even the 10 day/40 run means directly from the CFSv2 (which I’ve posted here), are of limited value, especially considering how jumpy they often are from one run to the next due to essentially no forecasting value that far out. So, this X-post being based on just one run is essentially of no value and was likely chosen by whoever that X-poster is due to how cold it is late in the winter. For example, here are the last two single runs from WxBell for Feb ‘27: 6Z 8/23/26: cold in E, warm in W 0Z 8/23/26: not surprisingly nearly the exact opposite! Here’s that x-post’s Feb. ‘27 map again: To help emphasize how laughably frigid this post’s Feb CFSv2 map is in the E US, check out how much colder it is vs the record coldest (in degrees F): -DC ~20 vs coldest 24.6 (1934) -Richmond ~22 vs coldest 28.2 (1934) -Chattanooga ~19 vs coldest 33.8 (1958) -Atlanta ~25F vs coldest 34.4 (1895) Cities’ coldest from here: https://www.weather.gov/wrh/climate @Terpeast

Regarding the MDR mandarin: The 0Z UKMET has TCG 30 hours earlier than the 12Z and is back to having a TS. At 168, it is just E of the Leewards moving rapidly WNW: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 78 HOURS FORECAST POSITION AT T+ 78 : 11.9N 29.3W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 26.08.2026 84 12.1N 30.6W 1009 28 0000UTC 27.08.2026 96 12.4N 34.7W 1007 32 1200UTC 27.08.2026 108 12.7N 38.6W 1004 35 0000UTC 28.08.2026 120 13.4N 42.8W 1005 38 1200UTC 28.08.2026 132 14.2N 47.1W 1004 43 0000UTC 29.08.2026 144 15.1N 51.8W 1006 39 1200UTC 29.08.2026 156 16.1N 56.4W 1007 41 0000UTC 30.08.2026 168 17.2N 60.9W 1008 36

During the last 90 days, 86 of them were in MJO phases 6, 7, 8, or 1! The other 4 were only barely into phase 5 (inside circle) and since records started in 1974 there’s no instance of a 90 day period with >95% of the days in either the WPAC or the W Hem/Africa: The closest is 7/25/15-10/22/15, which had 81 of the 90 days (90%) in 6-7-8-1: