Into Arctic Air

Heading back to Missouri today, I departed Cincinnati in a mild, humid air mass; the thermometer on our VW Beetle read 52 degrees F.  From there to western Indiana, I traveled under a low gray overcast, knifing through pockets of fog and drizzle.  The skies began to clear in Illinois and I approached St. Louis at sunset; Venus and a crescent moon gleamed in the southwestern sky and the temperature was 65 degrees F.  However, a bank of clouds across the western horizon warned of an approaching cold front.

By the time I reached Warrenton, Missouri, 30 miles west of St. Louis, the temperature had fallen to 50 and, twenty miles farther, a light mist coated the windshield and a strong west wind had developed.  Eighty miles west of St. Louis, the temperature had dropped into the upper 30s and, as I pulled into our driveway in Columbia, the car thermometer read 34 degrees F.

While I had clearly entered the dome of Arctic air that is dropping through the center of the U.S., I had barely penetrated its outer rim; 500 miles to our northwest, in the heart of the dome, lows of 20-40 degrees below zero have been reported.  Here in Missouri, we are expected to remain below freezing for the next week, with highs in the 20s and lows in the teens or single digits; most of the ice and snow associated with the Arctic front is currently forecast to stay south and east of Columbia.