Dewpoint Contour - -9 hr
Contour plot of the dewpoint temperature (F) for the contiguous US. The dewpoint temperature indicates the amount of moisture (or humidity) in the atmosphere. The amount of moisture in the atmosphere can affect how you feel and is used in the heat index computation (see above). Dewpoints above 65 reflect humid conditions. Summer dewpoints can reach the low 80s. Dewpoints above 50 mean that there is enough moisture in the atmosphere to generate thunderstorms. The higher the dewpoint, the easier storms form and the more potent they can become. An additional factor of low level wind convergence is also needed to help storms form (see below). Intense storms can form at dewpoints of 55 if the right conditions are in place including high convergence values.