Tuesday, January 20th, 2009: 9pm

THE BIG STORY...Another potential snowstorm...

As we are all accustomed to, there is another well hyped snowstorm that could be impacting our area Monday and Tuesday. Right now, it is two early to tell what precip type will be for this storm. However, the NWS and the GFS computer models voice some concern for this storm. From the NWS:

BY LATE SUNDAY...ALL EYES WILL BE WATCHING HOW THE MODELS DEVELOP THE STRONG TROUGH THAT IS FORECAST TO IMPACT THE WESTERN U.S. THE CRUX OF THE POSSIBLE WINTER STORM FOR THE OHIO VALLEY DEPENDS ON HOW DEEP THIS TROUGH DIGS. SHOULD THE TROUGH DIG FURTHER SOUTH INTO SOUTHERN CA/NV/AZ...THIS WILL PUMP UP THE SOUTHEAST RIDGE AND ALLOW WARMER AIR TO COME IN ALOFT WHICH WOULD RESULT IN A MAJOR ICING EVENT FOR THE OHIO VALLEY. IT SHOULD BE NOTED THAT IN PROGRESSIVE FLOW PATTERNS LIKE THIS...THE GFS TENDS TO OVER DEVELOP AND DIGTROUGHS TOO MUCH (WELL DOCUMENTED GFS BIAS). SO THIS IS SOMETHING TO WATCH. ON THE OTHER HAND...IF THE WESTERN TROUGH DOES NOT DIG AND HEADS MORE TOWARD THE EAST...THEN THE SOUTHEAST RIDGE WOULD BE MORE SUPPRESSED AND WE WOULD BE LOOKING AT MUCH MORE OF A SNOW SITUATION RATHER THAN ICE.

Here is the GFS map for Monday night:

Upon expanding this picture, you will see that there is a heavy band of precip in our area on Monday night. Also, the blue line along the Ohio River and the red line in southern Kentucky represent both sides of the 32 degree freezing line. This is definitely something to keep an eye on over the next few days.

Alex C.