Lowell Departs, More Activity to Come in the Pacific? AI Models Discussion 9-9-2026

  • Andy Hazelton
    Andy Hazelton

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Lowell Departs, More Activity to Come in the Pacific? AI Models Discussion 9-9-2026

We’ll start today’s look at TC activity in the Northern Hemisphere with systems in the Pacific, which continues to dominate thanks to El Niño.

West Pacific

There are currently no active TCs in the West Pacific. However, models are starting to indicate the possibility for another strong typhoon to form in the region near or to the East of the Mariana Islands sometime next week (Figure 1).

Figure 1: Google DeepMind 50-member ensemble forecasts of TC tracks and intensity over the West Pacific initialized at 06 UTC August 20, 2026, valid out to 360h. Data from Google.

This area has seen several typhoons this year, and it’s common during El Niño to see development shifted further East in the West Pacific. The 1000-member Google DeepMind ensemble (Figure 2) suggests a median TC genesis time around 6 days from now, with the potential for the system to get very strong later.

Figure 2: Google DeepMind 1000-member TC genesis timing and intensity forecasts for the potential West Pacific system, initialized at 06 UTC September 9, 2026. Figure from www.tcatlas.org.

Looking at the forecast upper-level winds, it looks like a TC would have a favorable configuration, with both poleward and equatorward outflow channels (Figure 3). It’ll also be interesting to see if a system does form and recurve into the mid-latitudes, which could have some implications for large-scale predictability in the Northern Hemisphere later.

Figure 3: AIFS forecast of 250-hPa winds initialized at 06 UTC September 9, 2026 and valid at 06 UTC September 17, 2026.

East/Central Pacific

The East/Central Pacific is finally slowing down a little bit, with Lowell weakening to the North of Hawaii. However, it looks like more activity could be coming over the next week or two, with Invest 96E a candidate to develop as it moves west, and another potential system behind it (Figure 4).

Figure 4: Google DeepMind 50-member ensemble forecasts of TC tracks and intensity over the East Pacific initialized at 06 UTC August 20, 2026, valid out to 360h. Data from Google.

It’s a little early to say whether either system might be a threat to Hawaii, which has already seen significant impacts from both Lala and Lowell this year. It looks like there may be a trough to the South of the islands that could cause any TC to weaken (Figure 5), but we’ll have to see how the pattern evolves as we get further into September.

Figure 5: AIFS forecast of 250-hPa wind initialized at 06 UTC September 17, 2026 and valid at 06 UTC September 17, 2026.

Atlantic

Despite being at the climatological “peak” of hurricane season this week, the Atlantic remains remarkably quiet, with no active TCs and none expected in the next 7 days. The only possible signal from models is for something to develop in the subtropics, possibly from a tropical transition event from a trough breaking off (Figure 6).

Figure 6: Google DeepMind 50-member ensemble forecasts of TC tracks and intensity over the Atlantic initialized at 06 UTC August 20, 2026, valid out to 360h. Data from Google.

Over the Main Development Region and much of the Southwest Atlantic, a large tropical upper tropospheric trough (TUTT) will dominate (Figure 7), leading to strong vertical wind shear and making development unlikely.

Figure 7: GraphCast forecast of 250-hPa wind initialized at 00 UTC September 9, 2026 and valid at 00 UTC September 16, 2026.

We’ll keep an eye on how things evolve as these new systems potentially form, and be back with another update soon!