Hurricane Dolly (2008) and warm sea surface temperatures. Dolly strengthened steadily beginning on July 21, and by the afternoon of July 22, it strengthened into a Category 1 hurricane on the Saffir-Simpson Hurricane Scale. At this point, the storm was located about 165 mi (265 km) east-southeast of Brownsville, Texas. Steady strengthening continued that evening and into the morning of July 23, at which point Dolly reached Category 2 intensity while just east of the Rio Grande Valley at 10:00 that morning with winds of up to 100 mph (160 km/h) and a minimum central pressure of 963 mbar. At 1:00 pm CDT
Hurricane Bertha (2008) 77 °F (25 °C), and its overall appearance was characterized by intermittent bursts of deep convection near the center. Eventually, by late on July 5, Bertha began to enter warmer waters and gain organization. Convection coalesced throughout July 6, and a series of microwave passes later that day indicated the formation of an eye-like feature, despite some tilt to Bertha's low- and mid-level circulations. Rapid deepening ensued as the aforementioned eye became readily apparent and convection in the eyewall cooled; Bertha became the season's first hurricane around 06:00 UTC on July 7, and by 21:00 UTC that afternoon, attained its