Heading east across the Great Plains today, I drove beneath bright sunshine from Denver into western Kansas. The air was dry and relatively cool, consistent with passing through the center of an atmospheric trough, caused by high pressure within a dip in the jet stream.
Meanwhile, south of the trough, thunderstorms, some severe, were marching across north Texas, Oklahoma and Arkansas. As I approached Colby, Kansas, a band of low clouds stretched across the eastern horizon, demarcating the eastern wall of the trough. Beneath those clouds, the wind had shifted out of the east and, by the time I reached WaKeeney, dense fog shrouded the landscape. Finally, as I descended into Hays (my standard layover site), the fog cleared and warmer, more humid air was moving up from the south.
Tomorrow, as I continue my eastward journey, the trough will have deepened in the West and the storms that plagued the Southern Plains today will have shifted eastward and north-eastward. In other words, I can expect to be driving through rain for much, if not most, of the day.
