* WHAT...Temperatures from 90 to around 100 expected...except up to 103 across the warmest mountains and interior valleys of San Luis Obispo county.
* WHERE...Interior mountains of Los Angeles, Ventura, Santa Barbara, and San Luis Obispo counties as well as the San Fernando, San Gabriel, Santa Clarita, Cuyama and San Luis Obispo interior valleys.
* WHEN...From 10 AM Tuesday to 8 PM PDT Thursday.
* IMPACTS...There is a high risk for heat illness for sensitive populations including the very young, the very old, those without air conditioning, and those active outdoors.
* ADDITIONAL DETAILS...The warmest temperatures with this event are expected to occur Wednesday and Thursday afternoons, with additional locations potentially being needed to be added to this advisory with time. Temperatures are expected to cool slightly after Thursday in some locations, but will remainabove normal into the following week.