Thursday, October 4, 2012

Winter Strikes Back

Banished to the North Country back in February, winter has not shown its face in the American Heartland for almost eight months.  Thanks to a northward displacement of the jet stream, chilly air has remained in Canada and we experienced one of the most prolonged periods of warm weather in recorded history; unfortunately, that stagnant weather pattern also produced a severe drought.

Dropping across the Great Plains, this week's cold front should push through Missouri overnight, bringing scattered showers and much cooler air.  Our highs over the next few days will match our early morning lows of the past few weeks and we might hit the freezing point by dawn on Sunday.  Not unusual for early October, this initial pulse of winter should silence the fiddlers and send the last of our summer birds off to the south.

The semiannual war between summer and winter has begun and, over the next two months, an undulating jet stream will produce an alternating atmospheric pattern of chilly troughs and warm ridges.  After enduring a long, oppressive summer, I and many others are rooting for winter and, of course, Earth's history is on our side.  Indeed, recent climate forecasts suggest that the La Nina should begin to break down by December and that the coming winter will be a more typical one for the Heartland.  Here's hoping that deep snows and heavy spring rains recharge our groundwater, streams and reservoirs.