10 Comments

Cool chart - I am going to have to study it a lot more 🌻 - I thought that sinking air over the Atlantic would mean no storms, and rising air means storms. Maybe I have it all mixed up?

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You are not mixed up. Sinking air means no storms. Rising air often means storms. I don't recall anywhere in the article suggesting the opposite is true.

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It's the velocity chart of rising/sinking air showing the rising.air is stuck over India/Africa and the sinking air over the Atlantic, that that's favorable for tropical storm development.  I must have missed something.

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author

Hi cat, these charts are a little complicated. Sometimes I hesitate sharing the plots because they can get confusing but I think it's worth trying! The sinking air portion is less important than the positioning of the rising air. When the rising air is over Africa or the Indian Ocean, it reduces vertical wind shear in the Atlantic and enhances storminess with disturbances moving west. In general, Atlantic tropical activity is greatest about a week or two *after* the passage of the rising air (so after it leaves the basin and the sinking branch moves in). Hope this helps make a little more sense of it all.

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The charts are about the MJO, right? When there is a moist air mass in the MJO, you get rising air which promotes stominess. The rising air is the green; the sinking air is the brown, and that discourages storminess. I understand the MJO moist phase should be here by now, which means a period of increased activity.

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Ty Mr. Lowry ⚘

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Very interesting to have a glimpse of the conditions that come before the modeling can start forecasting. (Hope I said that close to correct)

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Looking at those tracks, it looks like the ECMWF AIFS 8-day and Graphcast nailed it (so far). A new era in forecasting dawning?

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Its seems the re curve systems have always been easy for the models to resolve and done so far in advance.

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True. Even my own proprietary GIM-CF (Gut Instinct Model Coin-Flip) came up with that solution)

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