* WHAT...Dangerously hot conditions. Afternoon temperatures 109 to 117 expected. Major Heat Risk.
* WHERE...Portions of southwest Arizona and southeast California.
* WHEN...From 10 AM MST /10 AM PDT/ Tuesday to 8 PM MST /8 PM PDT/ Thursday.
* IMPACTS...Heat related illnesses increase significantly during extreme heat events. Overexposure can cause heat cramps and heat exhaustion to develop and, without intervention, can lead to heat stroke.