* WHAT...Dangerously hot conditions with high temperatures in the mid 90s to 103 expected.
* WHERE...Santa Ana Mountains and Foothills.
* WHEN...Until 8 PM PDT Friday.
* IMPACTS...Heat related illnesses increase significantly during extreme heat events.
* ADDITIONAL DETAILS...Low temperatures 5 to 10 degrees above normal will limit overnight relief from the heat and will increase the threat of heat-related illness.