Hurricane Boris (1996) - Meteorological History

Meteorological History

Hurricane Boris originated from a tropical wave that moved off the west coast of Africa on June 8. The poorly organized wave tracked westward across the Atlantic Ocean and Caribbean Sea and entered the Pacific Ocean on June 23. The first signs of a circulation on satellite imagery appeared on June 26, centered about 250 miles (400 km) south of the Gulf of Tehuantepec. The system gained enough circulation definition and rainbands to acquire tropical depression status on June 27.

Upon becoming a tropical cyclone, the Aviation forecast model predicted Tropical Depression Four-E to make landfall in Mexico as a weak tropical storm in 12 hours. Around that time, the forecast track was issued by the National Hurricane Center late on June 27, stating that it would receive an outflow near Hurricane Alma. At the same time, the UKMET model had Tropical Depression Four-E remaining offshore Mexico. The same model also had the depression becoming Tropical Storm Boris. The National Hurricane Center forecasted Tropical Depression Four-E to become Tropical Storm Boris and make landfall in Mexico with winds of 50 nmi (93 km). In the same advisory, it was noted that the outer rain bands of Tropical Depression Four-E had moved onshore Mexico.

The tropical cyclone moved northwestward at 8 to 10 knots, and for the next two days its maximum sustained winds strengthened from 30 miles per hour (48 km/h) to 75 miles per hour (121 km/h). A ragged eye appeared on satellite imagery just before landfall on the afternoon of June 29, at a peak intensity of 85 miles per hour (137 km/h). The center crossed the south coast of Mexico midway between Lazaro Cardenas and Acapulco. Shortly after landfall, Boris weakened to a depression and turned southwestward in response to a building subtropical ridge to its north. The system, thoroughly disrupted by the mountainous terrain of Mexico, dissipated on the July 1 after moving back over water just south of Puerta Vallarta.