Not sure NE or E winds keep the Western Basin cooler. NE or E winds push warm surface water west, forcing the bottom water currents to the east, therefore actually warming the Western Basin. West winds do the opposite - push warm surface water east, driving bottom currents from the eastern and central basins to the west, thus cooling the Western Basin. From the current maps I've seen that cooler water from the Central Basin doesn't get too far into the Western Basin later in the summer, but it might now with the thermocline still relatively shallow.