Most charts have an active link to a current online image of that chart. Theta-e ridge indicates possible burst point for convection. Direct sunlight and light winds adds to heat stress as well as heat build up in cars. Locate scale and magnitude of fog, haze, smoke, snowfall, rain, etc.
Snow covered areas tend to be lower in temperature.
Often record lows occur on snow-covered nights with light winds and clear skies. Lake effect snow favored regions. Higher PW indicates regions where there is a larger depth of moisture and higher moisture content. Warm air can evaporate exponentially more water than can cold air. Atmosphere will become more unstable through moisture advection and low level warm air advection.