1.) Rain builds back in late tonight and Tuesday morning and will favor the southern and eastern half of the state. Drier trends develop Tuesday afternoon as the moisture pulls northeast.
Forecast radar 11a Tuesday
2.) A surge of arctic air will pour into the region as we wrap up the work week, including single digit wind chills. Lows in the 10s and highs in the 20s can be expected Thursday and Friday.
Forecast temperature anomalies to close the work week.
3.) Despite the cold, snow chances look unimpressive, per the latest data. While we, personally, still believe there will be more of an arctic wave to deal with along the arctic boundary pressing Wednesday night into Thursday (enough to accumulate), modeling says “we’re crazy” and brings the arctic plunge in without much fanfare (flurries).
4.) Speaking of snow, modeling also says the 3rd wintry threat we spoke of Sunday (for about a week from now) arrives with a warm-up and is more of a liquid event. While we tend to think this is still a threat that could deal our region wintry conditions, it would be irresponsible of us not to convey the lower confidence (heck, modeling suggests we’re close to 60 degrees next Monday).
5.) Our thoughts on a snowy December began last summer as research began on the upcoming winter. It’s based off a variety of solutions, but leans heavily on the idea blocking would develop and help “lock in” an active pattern with just enough cold air to create the wintry “goods.” (Pressing cold and an active jet undercutting the cold to create winter storm potential). While bullish on snow (still are), we’ve never had out a very cold December forecast (instead only “slightly,” or 1 degree, below average). If the recent weekend trend is correct, it says the upcoming (10) day period we thought would essentially deliver a month’s worth of snow is incorrect. Sure that gives us the second half of the month to still make up for it, but it becomes increasingly difficult to see the wild model swings and inconsistency without relaying those inconsistencies to you, the viewer.
Our overall thinking remains (as stubborn as it may seem) on December, but please know we also see how this could bust. There’s a fine line between communicating both ideas to you. Confidence is lower than we would like it to be…
Since then, the European has begun to lock-in to a trend of bringing that SW energy out quicker and, in return, igniting a surface low to develop in the western Gulf of Mexico (GOM) Saturday before tracking northeast into the TN Valley (Sunday) and Great Lakes region (Monday).
Taken verbatim, this would spread a cold rain into central IN Sunday before colder air begins to change the rain over to a wet, heavy snow Sunday night into Monday morning across central IN. Heavy, wind-blown, snow amounts would result with such a solution for portions of central IN. Such a scenario would be a high-impact event. While the majority of model data (factoring in the GFS and Canadian, for example) is far from agreeing on such a solution, it’s important to note that a trend of such a scenario is beginning to develop within the powerful European forecast model. Furthermore, roughly half of the European’s (51) ensemble members agree on an impactful winter event in the Sunday-Monday time period for central Indiana.