The official high temperature for Brookings Monday was 102, just one degree shy of the record set on that date in 1973, according to the National Weather Service.
No heat-related health issues were reported by authorities or local clinics in Curry County, but many residents could be found heading up river or to the beach to escape the heat.
The last time Brookings surpassed the century mark was in July 2008. The high then was 108, according to the Curry Coastal Pilot's weather station located on its building at Highway 101 and Oak Street.
From 2009 to 2011, the highest recorded temperature was 97 degrees (Sept. 2011). The high temperature in 2012 was 87 degrees, again in September.
Monday's heat wave lasted one day, as the high temperature in Brookings Tuesday was only 69, at 8:47 a.m. By 5 p.m. Tuesday the high was 58 degrees.
The National Weather Service forecast called for a cooling trend over the next few days, with highs in the upper 60s to low 70s in Brookings. Meanwhile, inland cities such as Grants Pass and Medford are expected to hit the 100 degree mark today (Sept. 11) and Thursday.
Monday's heat in Brookings was caused by a warm air mass over Southern Oregon combined with the Chetco Effect, a local phenomenon that causes temperatures to spike in the Brookings-Harbor area, said National Weather Service Meteorologist Shad Keene.
"That's why they call it the Banana Belt of Oregon," Keene said.
The Chetco Effect, he explained, is when the angle of an easterly wind aligns with the Chetco River Valley, compressing and heating up air that follows the river to its end in Brookings. The air cools as it spreads out away from the river, which explains why the agency's weather station in Harbor recorded a peak high of 87 on Monday.
By comparison, the high temperature in Gold Beach, about 27 miles north of Brookings, was 72; and Crescent City, about 26 miles south, was 68 degrees.
On Monday, the Pilot's weather station in downtown Brookings recorded a peak temperature of 101 degrees at 4:45 p.m. The Brookings Airport station, used by the National Weather Service, recorded a high of 102 degrees, Keene said.