Temperatures this afternoon soared to the highest so far this year across the Rogue Valley.

In Ashland, the temperature reached 100 degrees at 3:03 p.m.

Medford hit the triple digits at 1:53 p.m., the National Weather Service reported.

It's the first time the heat has climbed above 99 degrees this year. The last time temperatures broke the 100-degree mark was July 26, 2013, weather officials said.

The temperature has only continued to climb today, with 104 degrees reported at the Medford airport — where temperature readings are taken for the city — at 3:25 p.m. Meteorologists expect the temperature to climb a few more degrees by day's end.

A building high pressure system is responsible for the temperature spike. Weather officials have said they expect a slight cooldown starting Wednesday, but that the high temperatures will stay in the mid- to low-90s for the rest of the week.