Guide
Valley heat and your air conditioner
Bakersfield's summer is long, dry and hot, and the official record shows how much work a home air conditioner is asked to do here.
The 1991–2020 averages
- 92.3°Fnormal June high
- 98.3°Fnormal July high
- 96.9°Fnormal August high
- 91.4°Fnormal September high
Bakersfield airport station, NOAA normals available through the NWS Hanford climate pages.
How often it reaches 100
Over 1991 to 2020 the airport station averaged 35.5 days a year at 100°F or above, and about 112 days at 90°F or above. The yearly count swings widely. Between 2001 and 2025 it ranged from 25 days of 100-degree heat in 2008 to 67 days in both 2017 and 2021.
A cooling season with that many hot afternoons means many more hours of run time than a system in a mild coastal town sees. Capacitors, contactors and fan motors age with those hours.
Annual counts from the same station's daily records (NOWData).
Warm nights
Heat that lingers after dark keeps systems running. Over 1991 to 2020 the station averaged about 16 nights a year when the temperature never fell below 75°F. On those nights the house never gets a break, and a system that is struggling has no chance to catch up before the next afternoon.
Farmland outside the city cools off more at night. The Shafter page compares a station in the fields with the airport.
What the heat does to equipment
Dust and dry heat work together. A coil packed with dust cannot shed heat, so pressures rise just when the air around the unit is hottest. Attic ducts and air handlers sit in spaces far hotter than the outdoor air, so a small leak there costs more cooling than it would elsewhere.
Practical steps help: change filters often in dusty months, keep the outdoor coil clear, and have the system checked before the first long heat wave. The tune-up page lists what a visit covers.
Heat is a health risk too
When the system fails during a heat wave, people who are older, very young or unwell are at the most risk indoors. If a house cannot be cooled, moving vulnerable people to a cooler place while the repair is arranged is a sensible step.
Where these facts come from
Talk it over with a contractor
Say what the system is doing and where the house is. You will be speaking with an independent HVAC contractor who works in Bakersfield and the towns around it.