There are many sounds of early spring; the rising chorus of birdsong, the chirping of tree frogs and the questioning hoot of the barred owl all come to mind. But it is the rumble of thunder that most signifies a change in the season.
As the jet stream drifts northward, the flow of Gulf moisture opens across the Heartland. Combined with more intense solar heating, this fuel ignites thunderstorms as Pacific cold fronts march across the country. Beginning along the Gulf Coast, the thunderstorm season moves northward through the spring, peaking in April across much of the Midwest. This evening, a band of storms is pushing through Missouri and, after a long, frigid winter, the sound of change is more than welcome.
We'll endure some cool showers on the back side of the front tomorrow morning but, according to the forecast, the first significant heat of spring will invade our region through the coming week. The southerly flow that brings this heat will, of course, inject more humidity into the Heartland and, as a result, the next round of thunderstorms will likely be more severe. This pattern will continue until mid summer; by then, the jet stream will direct Pacific storms across Canada and we'll bake in the hot summer sun, hoping for pop-up thunderstorms to bring relief.
