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TheForecast Post

A chronicle of American weather and climate  ·  Wednesday, 16 September 2026

Weather Trader Tropics MILEPOST 1014

August 21, 2026 Friday Evening Tropics

Pacific full tilt with plethora of active systems and more to come. Atlantic has 3 areas watched including Eastern MDR tropical wave.

What the month did

August 2026 was the warmest August in the 132-year national record (1895–2026), at 75.6°F against a 1991–2020 normal of 73.1°F (+2.5°F).

August 2026 was the 22nd-driest August in the 132-year national record (1895–2026), at 2.3in against a 1991–2020 normal of 2.7in (-0.4in).

NOAA/NCEI Climate at a Glance, contiguous United States. This is the observed record for the month, not a score of anything said in this piece — the forecast ledger begins 2026-08-17 and cannot reach earlier posts.

Headlines Friday Evening Across the Tropics

  • Atlantic basin comes back to life early next week with models showing a tropical storm in the Main Development Region in 6-days with development signal remaining steady since the 12z cycle. Still 40% to 50% range in the MDR but whatever survives may find much more favorable environment in the Western Atlantic.

  • A non-tropical area of low pressure off the coast of Portugal (yes, not a typo) may transition into a named tropical storm (Dolly — 20% from NHC) but the “look” on satellite still is more mid-latitude occlusion.

  • Another small area of convection in the central subtropical Atlantic also has low potential (20%) but is not impressive

  • Typhoon Saudel (17W) in the Western Pacific appears to be rapidly intensifying and should become Super by Sunday.

  • Hurricane Lala still going out in the open Central Pacific. Tropical Storm Moke following but remains poorly organized into Saturday. The threat to the Hawaiian Islands look low and indirect.

IR Satellite Loop into early Afternoon

You can see more Satellite Imagery at Squall Cloud —> LINK

Atlantic Tropical Outlook

Atlantic Basin Tropical Spaghetti Next 15-days

In 4 to 5 days, a tropical wave exits Africa AND we will have our best chance yet (or maybe of all of 2026) at a TS/Hurricane into end of August + early September.

AIFS-ENS 18z picks up a tropical wave in the MDR at Days 4/5 with moderate (40%) signal for development into a TS/Hurricane once it gains latitude still 8-9 days down the road.

The MDR is hostile due to dry air (Saharan Air Layer + dust) but the water is warm so the convection and circulation may survive until reaching warm western Atlantic waters.

ECMWF Ensemble 12z full-physics tracks next 15-days

Full Physics EPS Ensemble system remains excited about this tropical wave early next week with many (> 50%) with major hurricane intensity

Typical “Cape Verde” major hurricane — regardless of El Niño —> would be 12+ days before any U.S. impacts, but these usually/hopefully go out to sea.

NEW: Google Deep Mind 15-day Ensemble Tracks | 18z

34/51 members have at least one tropical storm / hurricane = 68% overall, with some outlier tracks toward/into the United States mainland.


Day 6 — Next Thursday Afternoon

The tropical wave is robust with a strong circulation and plenty of moisture, but there is dry air (Saharan Air Layer) to the north, and that’s wrecked all previous waves regardless of model excitement. So we should keep this “false alarm” signal in mind.


Extending HRES 12z (ECMWF) into Day 14 — Major Hurricane curving off the East Coast of the U.S.

And, for fun, here’s the GFS 18z 14-day forecast …

Non-Tropical Area of Low Pressure off Portugal that might get a name

The little low-pressure system west of Portugal is putting on a show, but the structure looks very much like a midlatitude warm seclusion cyclone. I’m not sure it will have time to transition to a fully tropical system that feeds off the ocean surface, but instead degenerate/weaken while moving into Portugal.

ECMWF HRES | Precipitable Water | Atlantic Tropics Next 6-days

We are still observing the current batch of tropical waves getting wiped out by a Saharan Air Layer — you can see the front of the warm/dusty air wipe out the MDR into early next week. But, then a tropical depression or storm forms (40%-50% chance) forms from a robust tropical wave.

Flagship model: ECMWF AIFS 18z —> Integrated Vapor Transport next 10-days

AIFS-Single 18z is semi-interested in the tropical wave into Day 5 (Aug 26) coming off Africa. That is perhaps a TD/TS in the model, and no longer a hurricane signal as Thursday.

Sea Surface Temperatures plenty warm now > 28°C (red)

Very warm off Africa with 28.5°C to 30°C. The rest of the basin is also very warm including 30°C in the Gulf. The Caribbean is a bit cooler than normal but still plenty sufficient for any intensity hurricane. However, highly unlikely we’ll see one anytime soon in the “shear shredding” Caribbean.

NASA Dust (GEOS-5) 12z — Saharan Air Layers continue to cruise across the Atlantic doing damage to tropical waves and stabilizing the tropical environment with warmth and dry air combined with subsidence at low levels.

The SAL is not giving up, and may brutally suppress the tropical wave we’ve been watching with a close eye into next week.

Tropical Equatorial Africa — 3 waves all lined up — more to come.

3 major tropical waves — still 3-4 days until that one over Niger and Mali arrives off the coast of Senegal.

Central and Eastern Pacific Tropics

Central Pacific —> Lala + Moke

The entire Pacific basin is lit up with activity — typhoons and hurricanes next 2-weeks

Tropical Storm Moke (45 mph winds) —> WNW remaining south of Hawaiian Islands

Moke is not expected to intensify very much — but we’ll see!

Eastern Pacific Hurricane Factory. 2-4 more TS/Hurricanes in coming 10-14 days

Western Pacific Tropics

Typhoon Saudel (17W) intensifying — rapidly north of Guam

Intensity will quickly increase to Major Typhoon status on Saturday

The track has changed — and will take a left turn (?) around Taiwan into China with it’s escape hatch blocked by a ridge to the north over Korea/Japan.

JTWC takes to 130-knots (Super Typhoon) in next 48-hours

Deep Mind has the track bend to the west and then southwest! Bizarre

HAFS-A 18z has a Super Typhoon motoring across the Western Pacific at 25°N latitude — plenty of warm water and fuel: Next 5-days:


Global Tropical Cyclones for more ACE information, as well as my original climatlas.com/tropical site now with the beautiful Interstate Highway theme and full of interesting content!

Forecast Eagle maps explorer under construction.

Also, Forecast Canada with some beautiful Arctic views.

Satellite imagery from Squall Cloud, and soon Radar Imager from Forecast dBZ.

Maps sourced from weathermodels.com designed and innovated by yours truly! Please subscribe there for real-time access to the newest maps, charts from all of the weather models including ECMWF and AIFS, and NOAA GFS/GEFS, HRRR/RRFS and Blend of Models (NBM). NOAA WPC and SPC for fronts/convective outlooks. Our own content is now sourced from hottestsince.com and weather.city and celsius.earth, and squall.cloud and weather.football and global-tropical-cyclones.com and precipitation.earth

My Atlantic Hurricane Season Forecast (2026)

From April 7, 2026: Atlantic Seasonal Hurricane Forecast: (11/5/2)

9-13 Named Storms (11 most likely)
4-7 Hurricanes (5 or 6 most likely)
1-3 Major Hurricanes (2 most likely)
Accumulated Cyclone Energy: 75-85 (well below normal)

NOAA 2026 Atlantic Hurricane Season Forecast

More details in Thursday, May 21, 2026 Tropical Update

Milepost
1014 · laid 2026-08-22T02:24:20.455000Z
Source
https://weather.substack.com/p/august-21-2026-friday-evening-tropics
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a075b631dd3270f083ceaacbd8b68d25fecf5dff290dd05912fffc8413676605
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