Saturday, December 22, 2007

Solstice Storm

On this shortest day of the year, a powerful winter storm is sweeping across the Plains and Midwest. This morning, the center of the storm is over Iowa and a secondary low has formed above northern Texas. The connecting cold front separates spring-like conditions to the east from cold, dry air to its west.

The combination of high pressure over the Intermountain West and the deep low over Iowa is creating a pressure gradient that produces strong, north winds behind the front. The secondary low is dropping snow throughout the central Plains and, as the primary storm center moves into the Great Lakes Region, blizzard conditions will develop across the northern Midwest. Here in Missouri, morning temperatures in the low fifties will give way to cold, north winds by evening, with rain changing to snow; 2-3 inches are expected.

On the bright side, the winter solstice marks the darkest day of the year and, from now until June 21, the days will gradually lengthen. In concert, the solar radiation will become more direct and winter will fade to spring; of course, this process will occur over three months and weather conditions will remain volatile along the way. In the meantime, we might as well enjoy the many natural highlights of winter, an unfairly maligned season.