 And in their wake, cooler air to end the week. But then there's another heat wave that starts this weekend. Your forecast calling for showers and thunderstorms overnight. Some of the storms could produce heavy rainfall. Low down to 75. Then tomorrow, sunny, high 89. Partly sunny Friday with showers likely, maybe a thunderstorm. Friday's high 84. Then mostly sunny Saturday. There is a chance of a shower or a thunderstorm. Saturday's high 88. Sunny on Sunday, high 92.