Humidity

Humidity, a measure of atmospheric moisture, is essential in regulating the evaporative demands on the grapevine and impacts the susceptibility of fungal diseases. Humidity goes through diurnal and seasonal cycles. Values of humidity are typically highest in the morning when temperatures are low and at a minimum when daytime heat is at its maximum.

Water stress from low levels of humidity can be seen in leaf loss, a reduction in vine metabolism, and fruit damage of loss.

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