With New Jersey now officially in the midst of a July heat wave expected to stretch into next week, a major priority for most will be figuring out how to stay somewhat cool. Temperatures will be the 90s for days with the heat index regularly climbing into the 100 to 105 range, the National Weather Service said Wednesday. Nearly all of New Jersey is under a heat advisory Wednesday and Thursday with the advisory likely to be extended well beyond that, forecasters say. Air quality alerts are also in effect in 11 counties. At 1 p.m. temperatures had reached 98 in Newark, 94 in Camden and 92 in Tre…