Unfortunately, evaporative coolers become ineffective when humidity exceeds 50-60%. In humid climates, they're not a practical primary cooling solution.
Why evaporative cooling fails in humid conditions:
The cooling effect of evaporative coolers depends on water evaporating into the air. When air is already saturated with moisture (high humidity), very little additional evaporation can occur. The result:
- Minimal temperature reduction (often less than 5°F)
- The cooler adds even more humidity to already muggy air
- Indoor conditions may actually feel worse than before
Regions where evaporative cooling doesn't work:
- Southeast US (Florida, Georgia, Alabama, Mississippi, Louisiana)
- Gulf Coast of Texas
- Coastal areas during summer months
- Tropical climates
- Anywhere with regular summer humidity above 50%
What about occasional use?
Some homeowners in marginal climates use evaporative coolers on dry days and switch to AC during humid periods. This can save money, but:
- You need both systems installed
- You cannot run them simultaneously
- Switching between systems can be inconvenient
Better alternatives for humid climates:
- Central air conditioning
- Mini-split systems
- Window AC units
- Dehumidifiers combined with fans
If you live in a humid climate, traditional air conditioning is the appropriate choice despite higher operating costs.