Against all odds and certainly against climatology, Subtropical Storm Ana has been upgraded to Tropical Storm Ana at 15Z today. She has transitioned from a hybrid cold-core system to a fully warm-core one, as shown by satellite soundings and imagery, and buoy obervations. There is evidence of a warm core aloft and near the surface, and as such, the strongest winds have migrated inward near the core. At 15Z, Ana was located at 29.9N 57.5W and tracking E at 14kts. Winds have reached 45kts and the central pressure has fallen to 996mb. This intensification and tropical transition is truly remarkable considering the environment there (21C SST and 30kts of westerly shear). The forecast is for a continued eastward trek, and intenisty to remain roughly constant, possibly weakening in the high shear. This is a balance of model forecasts, which range from maintaining Ana at current intensity, to dissipating her in the high shear.
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