The National Weather Service in Flagstaff says an area of strong high pressure will produce near-record to record heat this week across much of northern Arizona. Officials say isolated thunderstorms will be possible over the mountains starting on Tuesday as moisture values slightly increase across Arizona. A prolonged heat event this week will last through at least Friday. Several days of record temperatures are in the forecast, with the hottest days arriving Tuesday and Wednesday. An Excessive Heat Warnings is in effect for most areas below 5,000 feet through Friday. An increase in mid-level moisture will result in the possibility of a few isolated thunderstorms each afternoon beginning Tuesday.
