{ "number": 941, "headline": "May 21, 2026 Thursday Tropical Update", "standfirst": "Atlantic hurricane season starts June 1st and may be front loaded", "desk": "tropics", "dateline": { "place": "Weather Trader", "state": null, "lat": null, "lon": null, "site_key": null, "site_name": null, "site_url": null, "accent": null }, "edition": "2026-05-21", "published": "2026-05-21T22:55:26.387000Z", "updated": null, "access": "free", "body_html": "
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This is post number 941: Good Evening! Day 141 of 2026. 9 more days until start of Atlantic Hurricane Season. Thank you to paid subscribers for renewing (some for Year 3) \u2026 and all new folks for 2026. Coupon for Annual Sub (33% off)

Thank you to this week\u2019s new subscribers \u2014 newsletter growth continues!

Author: Dr. Ryan Maue (X @RyanWeather X @weathertrader)

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

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Link: Media Release from NOAA

Not much unexpected here from NOAA in their morning press release. The upcoming season has a 90% chance of being below normal to near normal \u2026 and only 10% chance of being above normal primarily due to El Ni\u00f1o in the equatorial Eastern Pacific.

The range of named storms is 8-14 and hurricanes 3-6 and major hurricanes 1-3, but you can point to combinations over the past several decades, and come up with 14/6/1 or 8/3/3 \u2026 largely dependent upon sub-seasonal features like the MJO, dust outbreaks, and what\u2019s happening in the Western Pacific typhoon alley with the monsoon. I\u2019d go down the middle with 11/6/2 and ACE of 80.

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Climate Prediction Center (CPC) details about 2026 Hurricane Season

Multivariate ENSO Index (version 2) \u2014> Link: NOAA page

The El Ni\u00f1o/Southern Oscillation (ENSO) - a naturally occurring anomalous state of tropical Pacific coupled ocean-atmosphere conditions - is the primary predictor for global climate disruptions. These can persist over several seasons and thereby produce severe regional effects.

The MEI, which combines both oceanic and atmospheric variables, facilitates in a single index an assessment of ENSO. It especially gives real-time indications of ENSO intensity, and through historical analysis - provides a context for meaningful comparative study of evolving conditions.

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Current Value is -0.6

I have always favored the MEIv2 to assess the intensity and evolution of ENSO since the climate system is much more complicated than the SST anomaly in arbitrary rectangles in the equatorial Pacific.

The El Ni\u00f1o of 2023-24 was not that long-lasting or intense, and really didn\u2019t negatively impact the 2023 Atlantic hurricane season because other factors overwhelmed the otherwise weak teleconnections.

The climate system has been in La Ni\u00f1a since summer 2024, and continues at weak Ni\u00f1a intensity through March/April (-0.6).

Wild cards:

Will we see strong atmosphere ocean coupling and teleconnection between the anomalous warmth in the central and eastern Pacific with the Northern Hemisphere into Summer/Fall? Yes, I think so, more along lines of 1997-98 (but less Super)

Late onset of El Ni\u00f1o in the MEIv2 could mean front-loaded hurricane activity

Eastern Pacific + Central Pacific Infrared Satellite

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Some convection along the monsoon trough / ITCZ but nothing spinning or expected to develop further

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Atlantic Basin Satellite Channels \u2014 major dust cloud coming off Africa

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GeoColor show the visible \u201ctrue color\u201d just as you\u2019d see from space \u2014 in geostationary orbit (locked in place to look down) \u2026 aside from the puffy clouds and some storms, you can see the milky brown haze = African dust or Saharan Air Layers (SAL) that come off Western Africa into the Atlantic Ocean. SAL is bad for the hurricane business = stable/warm layer that limits instability and convection (storms)

Infrared (Channel 13) colorized \u2014> showers and thunderstorms

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Water Vapor (Mid-Level Ch. 9) - troughs + areas of descending/dry air

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ECMWF 12z | Precipitation Type + MSLP | Next 8-days

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The Intertropical Convergence Zone (ITCZ) in the tropics along 5\u00b0N to 10\u00b0N is where moist air can ascend and form thunderstorms or like a convective pot boiling over = convection. In the coming weeks, especially into late June, we\u2019ll look for areas of disturbed weather \u2014 which means persistent convection \u2014 and potential formation of low pressure swirls along the ITCZ with tropical waves, in the Caribbean and Gulf of Mexico (America) with decaying frontal boundaries, and other pathways like tropical transition or subtropical cut-off lows. Lots of options/ways to form a tropical storm in the Atlantic in any given season.

The Bermuda High \u2014> Azores High in the subtropics usually keeps things quiet in the latitude around 30\u00b0N and suppresses the ITCZ to the south in late May into June. On the periphery of the Bermuda High, moisture plumes out of the Caribbean into the Gulf and then Texas + Southeast.

NASA GEOS5 \u2014> African dust plume forecast next 10-days

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NASA runs a version of GFS internally that is configured to ingest / test various satellite based instruments. Their dust algorithm with GEOS-5 is very good, and I really like to show the evolution of African dust (Saharan Air Layers) over the Atlantic.

Right on schedule into late May, we have a major plume coming off the continent that should enter the Caribbean in next 5-days, with persistent SAL flow into June.

North Atlantic Tropics | Quiet Next 7-days

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2 Tropical Waves \u2014 but neither will develop in the Atlantic or Caribbean \u2026 but will be watched as they enter the Eastern Pacific

Global Ocean Temperatures \u2014> Sea Surface Temperature (SST)

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Tropical storms need at least 26\u00b0C SST to form and intensify \u2026 and hurricanes most often become major with 28\u00b0C SST (at least) \u2026 the Atlantic has plenty of real estate that could support a TS or H, but nothing percolating as the basin is very hostile or unfavorable to formation. Note, it is the \u201cactual\u201d ocean temperatures that fuel hurricanes, not anomalies or deviations from climatology.

There are still rather cool (relative) areas in the Western Pacific and North Atlantic compared to the excessive warmth along the Equator and off the western coast of Mexico. The recent 20-year climatology highlights much better than an older 1991-2020 baseline.

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However, we do look at SST anomaly to see where excessive warmth may be located e.g. \"marine heat waves\u201d that could fuel stronger hurricanes than otherwise expected.

The Atlantic is actually cooler than past 2-decades across the Main Development Region from the Lesser Antilles (Caribbean) to the Azores and coast of Africa. This is NOT a positive signal you\u2019d expect for an active season.

My favorite parameter \u2014> Precipitable Water (PWAT) next 8-days

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Tropical storms and hurricanes are bundles of high moisture air > 2\u201d in the column (or more) so we look for areas of concentrated high PWAT air in the tropics \u2014> and we also can view frontal boundaries or dry air input from the middle-latitudes into the subtropics or tropics + Saharan Air Layers (dry)

Integrated Vapor Transport \u2014> IVT next 10-days

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The transport of rivers of moist air \u2014> IVT is great metric to show tropical storm development. Here, we see the Bermuda High / subtropical ridge in charge \u2014 extending to the Azores across the Atlantic.

Western Pacific Basin \u2014 Typhoon Season is Underway

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Watching area of possible development in 5-7 days near Mariana Islands, but nothing suspect in the next 48-hours from JTWC. Next name is Jangmi.

Ocean Temperatures (SST) very warm > 28\u00b0F over the \u201cwarm pool\u201d plenty sufficient for any category of Super Typhoon, assuming one can form, but actually slightly cooler than normal along the northern side of the warm pool.

ECMWF Full Physics Ensemble Tracks \u2014 50 members next 12-days

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Tropical Storm formation possible in 5-days, and then development into a strong Typhoon \u2014 but the full-physics system actually has 3 potential TS formation chances along the zonal monsoon trough

IVT shows the circulation and intensification into Days 8-10 (May 29-31)

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Pretty maps! IVT is under-utilized for tropical storm formation forecasting

WPAC Precipitable Water (PWAT) next 8-days

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Plenty of convection / instability across the MDR of the WPAC mainly east of the Philippines \u2014 Next 12-days ECMWF 12z (MSLP+Precip)

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ECMWF AIFS-Single v2 (Data Driven Forecast System)

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ECMWF flagship A.I. weather modeling system Days 5-12 \u2014 develops a 950s mb typhoon (Cat 3)

And, the ensembles from AIFS-ENS v2 (different than AIFS-Single) \u2014 quite ambitious with the storm formation and intensification!

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Eastern Pacific Tropics | Quiet next 7-days

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Ocean temperatures are very warm across the basin with the cooler water roughly WNW of 15\u00b0N and 110\u00b0W

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Thank you for reaching the end of this post! Hopefully you enjoyed the tour of the global tropics and what\u2019s coming in the weeks/months ahead in the tropics here on Weather Trader on Substack.

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For 2026 Hurricane Season: Every 6 or 12 hours, we get an update including these model output:

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My Atlantic Hurricane Season Forecast (2026)

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

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