Those of us who reside in the Interior of North America know that storms generally arrive from the west as Pacific or Canadian cold fronts march eastward across the U.S.; at times, a cold front may sag southward or warm, humid air may bubble northward but it is unusual to have showers and thunderstorms move in from the east. Nevertheless, the latter phenomenon has developed in Missouri over the past twenty four hours.
The atmospheric culprits for this anomaly are high pressure over the Great Lakes and low pressure over the south-central U.S. In the Northern Hemisphere, winds circle clockwise around domes of high pressure and counterclockwise around centers of low pressure. The combined effects of the present atmospheric structure are thus creating an easterly flow across Missouri and mixing of the two currents ignites pop-up showers and thunderstorms.
While the rain provides temporary relief from our oppressive summer air, it soon only adds to the humidity. What we need is a potent Canadian cold front that sweeps dry, cool air across the Heartland but such a forecast is not currently in sight. We are left to escape indoors and dream of October.
The atmospheric culprits for this anomaly are high pressure over the Great Lakes and low pressure over the south-central U.S. In the Northern Hemisphere, winds circle clockwise around domes of high pressure and counterclockwise around centers of low pressure. The combined effects of the present atmospheric structure are thus creating an easterly flow across Missouri and mixing of the two currents ignites pop-up showers and thunderstorms.
While the rain provides temporary relief from our oppressive summer air, it soon only adds to the humidity. What we need is a potent Canadian cold front that sweeps dry, cool air across the Heartland but such a forecast is not currently in sight. We are left to escape indoors and dream of October.
