The Diamond Fire burning northeast of Fountain Hills since this past weekend has surpassed 1,000 acres in size, according to a recent update.

The Mount Ord fire lookout in the Mazatzal Mountains reported smoke on Diamond Mountain southwest of the community of Sunflower about 4 p.m. on Saturday, July 22. The community is located on State Route 87 (Beeline Highway) about 30 miles northeast of Fountain Hills.

The fire was burning on the top one-third of Diamond Mountain and firefighters arriving at the scene were unable to take immediate action due to monsoon downdrafts in the area. The weather also kept air support from attacking the blaze. The fire was monitored through the evening with fire behavior active until about 1 a.m. on Sunday, July 23. Fire officials considered the at-risk infrastructure to be the community of Sunflower, SR 87 and high voltage power transmission lines.

Fire officials closed SR 87 in both directions between the Bush Highway (northbound) and SR 188 (southbound) overnight Tuesday to allow for control operations near the fire. The highway was reopened by Wednesday morning. Motorists should be aware of the potential for additional closures.

The Rio Verde Fire District has told Verde residents that while the fire posed no danger to the communities, they warned of potential smoke that might aggravate respiratory problems.

According to the Southwest Fire Incident Information Center website (inciweb) update on Wednesday, July 26, the fire had burned approximately 1,034 acres and had zero containment. There are 260 fire personnel reported battling the blaze with air support. The cause of the fire remains listed as under investigation, but there were reports of lightning activity in conjunction with the storms in the area, thought to be the cause.