Weather Underground midday recap for Monday, July 22, 2013.
Wet and unsettled weather continued in the eastern half of the nation on Monday. In the north, a low pressure system in southern Saskatchewan trekked eastward near the Canada-U.S. border through the day and became positioned just north of Lake Superior by the end of the day. As this system headed eastward, an associated warm front became nearly stationary as it reached through the Ohio Valley into the Mid-Atlantic States, while the associated cold front trailed across the Upper Midwest into the Central Plains. Strong to severe thunderstorms became possible along and ahead parts of the cold front in the afternoon and evening hours. The Storm Prediction Center issued a slight risk of severe thunderstorm development for parts of the Upper Great Lakes through parts of the Central Plains and the Ozark Plateau into the Mississippi Valley. While the primary threats with severe weather in these regions were damaging wind gusts and large hail, a few tornadoes were also possible in parts of Michigan¼’s Upper Peninsula and Wisconsin. Meanwhile, numerous scattered showers and thunderstorms with periods of heavy rainfall developed near and to the south of the stalled associated front extending across the Ohio Valley into the Mid-Atlantic. Waves of energy along the boundary helped produce more organized storms through the day.
Out West, monsoonal moisture triggered showers and thunderstorms across areas of the Desert Southwest and into portions of central California and the central Great Basin.
Temperatures in the Lower 48 states Monday have ranged from a morning low of 30 degrees at Stanley, Idaho to a midday high of 100 degrees at Alva, Okla.