Yesterday set two (as of yet unofficial) records for the hottest highest and lowest temperatures recorded for a July 17th at Grass Valley wastewater treatment plant’s weather station. 101F for the high temperature and the “coolest” temperature was 71F.

July 17, 2023 daily temperature graph compared to normals

The maximum and minimum temperatures are unofficial records for now. “We only issue RER (Record Event Reports) for our official Airport climate sites, so you won’t see a report from our office about that site. Those won’t be ‘official records’ until the National Center for Environmental Information  (NCEI) publishes them, about 4-6 weeks later,” explained Michelle Mead, the Meteorologist in Charge (MIC) at the National Weather Service in Sacramento.

The data collected is available in almanac form on the National Weather Service’s website under NOWData. The weather station has been in operation since 1966.

Grass Valley Station No. 2 Almanac for July 17
Grass Valley Station No. 2 Almanac for July 17. NWS Sacramento

Temperatures will cool to around average today and Wednesday. Widespread moderate heat risk returns Thursday, and areas of major heat risk develop Friday and persist into the weekend. Stay cool and hydrate!