A strong subtropical storm has transitioned to tropical, and has 50kt sustained winds and a 982mb MSLP, making it TS Delta, the 25th named storm of this unprecedented season. It is well away from land, located at 25.9N 40.5W and tracking SSE at 8kts. The convection and outflow are very healthy, and while the SSTs are only 25C or so, the tropopause temperature is colder than average too, so the temperature DIFFERENCE between the inflow and outflow levels is still enough to support a hurricane. The forecast calls for some strengthening, perhaps reaching hurricane status Thursday night into Friday morning, then becoming extratropical. The track is northerly at first (hence being nudged equatorward toward warmer SSTs) then southerly back into the mid-latitudes. The NTC is now 253%. If it is upgraded to a hurricane tomorrow morning (just supposing), the NTC would jump to about 256%.
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