Middlebury College maintains the following practice and competition weather guidelines.

We use Weather Underground to determine temperature, wind chill, and direction of wind. This weather web site has a station on campus.

Cold Weather Guidelines

Temp Practice Game
Above 10° Allowed without modifications. Allowed without modifications.
From 0° to 9° Allowed in modified format. Teams may choose between two 45 minute sessions separated by a mandatory 20 minute indoor warming period, or one hour of continuous practice. One hour practice times may be slightly increased or decreased depending on factors including time of day, cloudiness, or closeness to the upper and lower limits of 9° and 0°. Allowed in modified format. Teams may choose to warm up on the indoor turf one hour before competition or ten minutes outside with a 15 minute break indoors before the game. If the warm up is indoors, the  turf will be divided in half with each team warming up on their half of the indoor turf with a reduced number of players. All pregame announcements and the national anthem will be cancelled and the start of the game will be immediate. Half time will be extended to 30 minutes with a 5 minute outdoor warm up. All Middlebury teams must purchase hand and foot warmers .
Below 0° All outdoor practices will be suspended. All outdoor games will be suspended.

Warm Weather Guidelines

On very hot days, either during the fall or spring, Sports Medicine will use a Wet Bulb Globe Test to determine the safety of practicing outside. A Wet Bulb Globe Test (WBGT) is a tool that takes into account the ambient temperature, relative humidity, air motion, and amount of radiant heat from the sun.

WBGT Games and Practice
<82.0° Normal Activity with no restrictions.
82.1° to 89.9° Two hours max with 4 breaks lasting 4 minutes.

For Football: Restrict to helmet, shoulder pads, and shorts. Remove all equipment for conditioning.
90° to 92° Maximum length of practice is one hour, no protective equipment may be worn during practice and there may be no conditioning activities. There must be 20 minutes of rest breaks provided.
>92.1° No outdoor workouts until cooler WBGT reading occurs.

As environmental temperature and humidity increase, there is an increase in the heat stress that is placed on the exercising individual. Exercise in the heat causes athletes to rely on evaporation of sweat from the skin as the primary method of dissipating heat that is produced by the working muscles. As humidity increases, the ability to dissipate heat through evaporation is further hindered, thus causing the body to have an increased body temperature, which increases the risk of Exertional Heat Stroke. (Kory Stringer Institute)