The City of Poway closed its Iron Mountain and Mount Woodson trails due to an excessive heat warning from the National Weather Service.
The trails will be closed Monday and Tuesday.
The city said it closes its trails if temperatures are expected to rise above 100 degrees or if there is a heat advisory.
The trails were last closed from July 24 to July 27.
On July 27, the City of Poway tweeted, "Please continue to stay off the trails. It's especially important right now with the extreme heat and high risk for brush fires. Thank you for patience and understanding."