Summer afternoons in the valleys of eastern California and western Nevada usually feature dry low level relative humidity. In certain cases where low levels are very dry (single digit relative humidities) and enough instability for showers and/or thunderstorms exists, there is the heightened possibility for severe (over 60 mph) outflow winds. Now, severe winds are possible from strong thunderstorms in many cases, even without very dry surface relative humidity. However, what makes very dry surface or low level conditions special is that severe outflow winds are possible even with w eak convection such as light showers...or even just cumulus clouds! When severe winds are produced by convection with little or no rainfall reaching the ground, it is referred to as a "dry microburst". Microbursts can be of significant danger to aviation and, if they are strong enough, life and property. Before we move onto what conditions we look for to determine the threat for dry microbursts,