Tracking scattered rain chances and building heat this weekend

TODAY: The weekend starts dry, with temperatures quickly rising to the upper 80s and low 90s by early afternoon. The heat index reaches the low triple digits, between 100 and 103 degrees. Scattered storms then develop during the heat of the day by midafternoon, continuing into the early overnight hours.

TOMORROW: Sunday is drier and hotter as the heat index climbs to 105 degrees or higher. Isolated storms are possible by the late afternoon, but relief will be much more limited.

EXTENDED: A heat wave is expected early next week, prompting ABC 17 Stormtrack Weather Alert Days from Sunday through Tuesday for the heat index up to 105 degrees or higher. Rain chances decrease under a dome of high pressure on Monday and Tuesday, but this pattern begins to break down midweek. Showers and storms developing from Wednesday onward will bring a dramatic cooldown later in the week, with highs trending to the low 80s into next weekend.