So far this season, we've seen two systems that threatened to bring a chance of snow or sleet, but fizzled. The weekend after Thanksgiving, the forecast for Cape Girardeau called for a good chance of rain followed by a switch to snow, with around an inch of accumulation expected. The rain came, but not the snow. Since then, another cold front has delivered rain and cold air, but no snow.
Based on personal experience, these "rain changing to snow" forecasts are typically a bust. The moisture always seems to vanish just before the temperature drops below freezing.
Another weather system next week is expected to bring more rain and cold air. Snow? The odds don't look too good. The forecasters at the National Weather Service office in Paducah had this to say during this afternoon's forecast discussion:
AS WITH PREVIOUS SYSTEMS...THE LOW LEVEL MOISTURE IS EXPECTED TO EXIT FASTER THAN THE COLD AIR INTRUSION. THEREFORE...THE SWITCH FROM A RAIN/SNOW TO SNOW FORECAST IS FAIRLY RAPID TUESDAY EVENING. BY MIDNIGHT AND THROUGH DAYBREAK WEDNESDAY...SIGNIFICANT DRYING TAKES PLACE...LIMITING ANY MEASURABLE PRECIPITATION CHANCES TO THE PENNYRILE REGION OF WEST KENTUCKY. FOR NOW...I HAVE NOT INTRODUCED ANY MEASURABLE SNOW OR ICE ACCUMULATION FOR TUESDAY NIGHT.
The Dartboard Forecasting System
I'd like to take this opportunity to present my non-patent-pending Dartboard Forecasting System, loosely based on a science fair project I put together in middle school. In this graphic, produced using the finest in high-tech weather forecasting technology (Photoshop), you can see the typical outcomes for a "rain changing to snow" situation here in Southeast Missouri:
Most of the time (in green), we get squat. Maybe lots of rain, but no snow except for flurries. Sometimes the forecast (in red) actually pans out, and we really do see rain changing to decent snowfall. And in extremely rare cases -- the Blizzard of '79 comes to mind -- Mother Nature quickly skips past the rain phase and goes straight to Major Oh-My-God Blizzard mode.
With the parade of weather systems that are coming through, we're eventually going to see a good snow. But don't hold your breath. And kids: don't skip your homework expecting a snow day every time.