December 2013 archive

Your complete 7-Day IndyWx.com forecast can be found in the video player to the right of this post.

Before we begin to discuss the potential wintry mischief ahead for late week, it’s important to stress that there are still several unanswered questions out there that will have to be ironed out with time as we go through the next couple of days.  That said, the latest data continues to suggest the potential is there for a rather prolonged, multi-day, winter weather event looming.  This won’t come from some sort of powerhouse storm system, but instead multiple waves of energy (low pressure) moving along a pressing arctic boundary.  The continued “curious” item here is the interaction with the arctic boundary’s progress south and east and the resistance that will be put forth from the southeast ridge.

The latest 500mb pattern off the 0z run of the GFS forecast model has “trouble” written all over it and we must keep a close eye on things as we move forward the next couple of days.  Additional model data from the European forecast model and Canadian are also suggesting fun times ahead.

This image is valid Saturday evening and shows a couple of important items- the southeast ridge and the associated fight it’ll put up with the pressing arctic front, as well as “renewed” energy organizing across the Four Corners region, organizing before a track northeast.

The way we currently see things panning out would suggest the threat of light accumulating snow is on the table late Thursday night through Friday followed by a dry and cold day Saturday. That said, as shown above, renewed energy will move northeast the second half of the weekend into early next week and be responsible for spreading moisture back over what will be an unseasonably cold air mass in place, certainly one conducive for wintry precipitation.

It’s important to note that this isn’t just a snow event, but some places of the immediate coverage area (central Indiana, in particular) could experience an icy mixture of sleet and freezing rain, as well.  It’s far too early to talk about any sort of storm total accumulations as these type “overrunning” events can surprise…  That said, we are gaining confidence on “part 1″ of this event providing light accumulating snow for most of central Indiana Friday- light meaning less than 3”.  Additional accumulation of wintry precipitation would occur with “part 2” of this event during the back half of the weekend.

Again, it’ll be crucial to keep up to date with the latest forecasts and developments as things become clearer as we move forward.  As of now, keep a mental note in the back of your mind that the possibility is there for accumulating snow late Thursday into Friday, as well as later in the weekend…