The National Weather Service office in Tulsa has issued a heat advisory for Northwest Arkansas.
The advisory will remain in effect until 9 p.m. tonight and from noon to 9 p.m. Friday.
The hottest temperatures of the year so far will occur today, with afternoon highs ranging from 95 to 105 degrees. Heat index values will climb into the 105 to 110 degree range across the area this afternoon, the weather service report says. The highest reading will be in eastern Oklahoma and west central Arkansas.
Even hotter temperatures are expected Friday, with lower humidity levels than today, according to the report. Afternoon heat index values will still approach 110 degrees in some places Friday afternoon.
A weak cold front will push through the area by Saturday bringing somewhat cooler conditions, although heat index values will likely still exceed 105 degrees in some places this weekend into early next week.
The heat index is measured in shady conditions and direct sun exposure can increase the index as much as 15 degrees the report says. A heat index of 105 degrees is considered the level where many people begin to experience extreme discomfort.