Bud Reached Cat 3 Intensity Due to Warm Water Surface; Gulf of Mexico Also Very Warm

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An unusually early category 3 hurricane in the East Pacific (Bud) likely caused by somewhat warmer than normal sea surface temperature anomalies (SSTA). A look at the North Atlantic tropics/subtropics SSTA reveals a very warm signature in the Gulf of Mexico.

Bud reached major category 3 hurricane status south of Mexico the past 24 hours which is very unusual for the first half of June. The primary contributor to this exceptional strengthening of Bud is the persistent warmer than normal ocean surface present for nearly 18 months southwest of Mexico. The anomalous warmth has been present independent of the ENSO regime in the eastern equatorial Pacific Ocean.

Are there any unusually warm zones in the tropical/subtropical North Atlantic which may lead to unusual intensification of a tropical cyclone? Yes! The west and central Gulf of Mexico are much warmer than normal (Fig. 1) and if a tropical system crosses this warm water the potential for rapid intensification is present.

Fig. 1: In the North Atlantic tropics the main development region for hurricanes (central/east tropical North Atlantic) is cooler than normal. However, the Gulf of Mexico is much warmer than normal.