The higher temperatures means higher humidity as humidity goes up as temperature does...... Over watering an already humid plant that cant transpire to the humid air makes plants look like that.....
Relative humidity
From Wikipedia, the free encyclopedia

A
hygrometer is a device used for measuring the humidity of air.
Relative humidity is a term used to describe the amount of
water vapor in a mixture of air and water vapor. It is defined as the
partial pressure of water vapor in the air-water mixture, given as a percentage of the
saturated vapor pressure under those conditions. The relative humidity of air thus changes not only with respect to the
absolute humidity (moisture content) but also temperature and pressure, upon which the saturated vapor pressure depends. Relative humidity is often used instead of absolute humidity in situations where the rate of water evaporation is important, as it takes into account the variation in saturated vapor pressure.
Definition
The relative humidity
of an air-water mixture is defined as the ratio of the
partial pressure of water vapor (H2O)
in the mixture to the saturated
vapor pressure of water
at a prescribed temperature.
Relative humidity is normally expressed as a percentage and is calculated by using the following equation:
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thanks wiki