Enjoy beautiful weather for Memorial Day, because rain could be coming Tuesday evening, then maybe more rain, followed by the hottest stretch of weather in nearly 10 months.

The temperature hasn't hit 90 since Sept. 1, and there hasn't been a heat wave - three straight days of 90 or more - since early August.

Philadelphia's hottest day so far this year was April 10, which hit 89.

This week, that could all change, forecasters say.

Highs in the low 90s are forecast for Thursday, Friday, Saturday and Sunday, according to the National Weather Service.

Next Monday might see a high back in the upper 70s, according to Weather.com's extended forecast.

Today should see a high in the upper 70s, under sunny skies.

Tuesday, showers are possible throughout the morning and afternoon. By early evening, they become likely, with heavy rain and thunderstorms possible. Again, the high should be in the upper 70s.

The chance of more showers or thunderstorms Wednesday morning and afternoon is low - about 20 percent - with the odds rising to about 30 percent during the evening.

Thursday through the weekend should not only be hot, but mostly sunny, with lows around 70.

For more on the forecast, go to Philly.com's weather page.

Contact staff writer Peter Mucha at 215-854-4342 or pmucha@phillynews.com.