Weather Underground midday recap for Monday, July 01, 2013.
Hot weather conditions continued in the West on Monday, while showers and thunderstorms persisted in the East.
Out West, another extremely hot day developed across the western states as an expansive ridge of high pressure over the Southwest and Great Basin continued building northward. Temperatures in parts of California, the Desert Southwest, and the Great Basin reached well past the century mark, while highs ranging from the upper 90s to the lower 100s were possible from parts of the Pacific Northwest interior through areas of western Montana. Excessive Heat Warnings continued from western Arizona through most of California and Nevada, as outside activities remained dangerous for the region. Heat Advisories were also issued for areas of northwestern Nevada through parts of Washington, northern Idaho, and northwestern Montana. Hot and dry conditions coupled with dry thunderstorm potential in parts of Arizona and Nevada kept fire danger high through the day. Meanwhile, just east of this ridge, moisture pooling along a nearly stationary frontal boundary and warm afternoon temperatures led to scattered storms from parts of eastern Colorado through western Texas.
In the East, hot and humid weather conditions continued for the eastern third of the nation as the region remained in between an upper trough of low pressure over the Ohio and Tennessee Valley and a ridge of high pressure in the western Atlantic Ocean. Ample warm, moist flow streamed in from the south-southwest and pooled along a lingering frontal boundary over the Eastern Seaboard, kicking up more showers and thunderstorms from New England areas through the southeastern corner of the nation. A variety of Flood Watches and Warnings were issued from parts of southern Maine through northern and western Georgia in anticipation of heavy rainfall. Meanwhile, behind this activity, showers accompanied a cold front dropping across the Great Lakes and areas of the Northeast, while low pressure supported strong thunderstorms in portions of the Ohio and Tennessee Valleys. The Storm Prediction Center issued a slight risk of severe thunderstorm development for central and eastern Kentucky this afternoon with threats of locally damaging wind, hail, and possible brief tornadoes.
Temperatures in the Lower 48 states Monday have ranged from a morning low of 37 degrees at Leadville, Colo. to a midday high of 109 degrees at Needles, Calif.