On average, apps will run about 15% slower in the summer, according to research from Apteligent a mobile app intelligence platform.
Why? Due to the science behind the propagation of radio waves. Increases in water vapor cause attenuation of the waves, especially at higher frequency bands. This means that the humid summer months will cause degradation in signal strength, and slight delays in data delivered to the handsets of consumers. The impact is pronounced in the data.
The accompanying compares latency of apps in the summer against the winter.