Clear skies will allow for temperatures to fall into the middle to upper 40s tonight in Washington and Baltimore. Areas of frost are possible in the northern and western suburbs where temperatures may dip into the lower to middle 30s. The one factor of importance for frost to develop tonight will be calm winds. The gusty winds across our area this afternoon are expected to die down as high pressure builds in across the DC Area overnight into the predawn hours on Tuesday. If conditions remain breezy overnight, frost will be less widespread. Regardless, if you have sensitive plants and live in the outlying suburbs, you might want to cover them.