A ridge of high pressure is expected to bring temperatures to a sizzle this week in the Sacramento region and throughout the state.

Temperatures on Sunday are forecast to reach the low 90s, the beginning of a small heat wave. The National Weather Service is predicting triple-digit temperatures, with Tuesday bringing a high to Sacramento of 108 degrees.

“We’re a little bit above average, but no records,” said Courtney Obergfell, a weather service forecaster in Sacramento.

The heat will back off to a high of 100 degrees on Thursday and continue to retreat in time for relatively cooler weather on the Fourth of July. The weather service is calling for a high of 94 degrees on the holiday.

Farther north, though, high temperatures are expected to be dramatic. In Redding, a high of 113 degrees is predicted Tuesday, followed by 111 on Wednesday and 110 Thursday. A high of 104 degrees is expected for the Fourth of July at the far northern end of the Sacramento Valley.

Here’s the seven-day forecast for Sacramento:

Sunday: Isolated showers before 11 a.m. Partly sunny, with a high near 92. Southwest wind 6 to 10 mph. Chance of precipitation is 20 percent.

Sunday night: Mostly clear, with a low around 59. South wind 9 to 13 mph.

Monday: Sunny and hot, with a high near 99. South wind around 8 mph becoming west in the morning.

Monday night: Mostly clear, with a low around 63. South wind around 8 mph.

Tuesday: Mostly sunny and hot, with a high near 108. South wind around 6 mph becoming west-southwest in the morning.

Tuesday night: Partly cloudy, with a low around 68.

Wednesday: Mostly sunny and hot, with a high near 105.

Wednesday night: Mostly clear, with a low around 68.

Thursday: Sunny and hot, with a high near 100.

Thursday night: Partly cloudy, with a low around 65.

Friday: Mostly sunny and hot, with a high near 96.

Friday night: Partly cloudy, with a low around 64.

Independence Day: Mostly sunny, with a high near 94.