WINTER STORM WARNING STARTS AT 1:00 PM TODAY
Central Indiana is bracing of another winter storm starting this afternoon and into Wednesday morning. A winter storm warning in effect from 1 PM today through 1 PM Wednesday. Snowfall will likely return for the evening commute and become heavy after sunset and through the early morning hours of Wednesday.
Winter advisories for this storm stretch from Utah to Maine with a swath of snow cutting through the heart of Indiana. The National Weather Service has a 60% probability of 6” of snow (that’s high) through central Indiana. As of now, the heaviest totals are expected to fall north of the storm track.
SNOW SWATH HEAVY!
The storm will come in two phases with an initial surge of moisture – known as the “onslaught” snow, then follow-up with a break or lull as the surface low nears. This cut off of precipitation could drastically reduce snow totals south of the city – stay tuned. The second phase of the storm will be the passage of an upper level low and colder air pouring in behind the storm system. Locations under this feature have the potential to get the highest snow amounts – currently projected north of the city!
Various snow forecast techniques, coupled with a group of model forecasts suggest 5” to 9” of snow in the city with this storm. A 6 model average of snowfall has 6” in the city with a range from 5.9” to 6.8”. These numbers are based upon a standard 10 to 1 ratio and may be a bit conservative – we think a 12:1 ratio may be better suited with this storm with strong upper level air dynamics. A strong jet stream will deepen a surface low and tap gulf moisture, then surge northeast into the state. While there is a growing potential of a “dry slot” or cut off of moisture in part of the area south, locations north of the low track may see snow accumulation of 12”.
To date ranks 4th snowiest on record and among the snowiest 8% on record. With 36.8” down, new snow Tuesday and Wednesday will push us over 40” of seasonal snowfall for only the 9th time on record.
SOUTHERN SYSTEM THIS WEEKEND?
We will watch this southern storm track for the potential of a new system with more snow Saturday and Sunday. Not all computers long-range agree on location but it is early and bears close watching.