All options are on the table. That means rain, storms, ice and snow. Here is what the National Weather Service is saying:
.Long Term...(Wednesday through Monday) Issued at 316 AM EST Tue Dec 5 2023 Wednesday through Friday... Dry conditions will oversee a moderating pattern through the remainder of the workweek. Surface high pressure crossing the central CONUS Wednesday...will be followed by a broad upper-level ridge crossing the US over Thursday-Friday while a strengthening surface gradient is focused into central Indiana between the slowing surface high to our southeast and deepening low pressure along the Canadian border. Lingering subsidence cloudiness Wednesday will hold seasonable chill over the region, before solid warm-advective winds and ample sun Thursday boost readings into the low to mid-50s for the first time in a week. Above normal marks will continue into Friday amid increasing clouds ahead of the next system/front taking shape across the central US. High confidence in precipitation-free conditions over all of the region through these three days with no forcing aloft, generally dry mid-levels, and adequate low level moisture not expected to return until the Friday night timeframe. Saturday through Monday... Latest guidance are continuing to show an early winter storm advancing in a northeasterly direction from the Middle Mississippi Valley to the Great Lakes this weekend. While disagreement still lies between different models as well as ensemble members, latest trends do show better model agreement...and with perhaps a farther north surface low track through the Midwest due to slightly faster secondary upper level energy that would serve to negatively tilt the H500 trough farther upstream/to our west. For central Indiana this would translate to a deeper presence in the system`s warm sector late this week into the weekend, with increasing coverage of rain showers amid advection of greater deep moisture. At least a 6-hour period of steadier/heavier rain (with embedded thunder likely for at least portions of the region) would pair with precipitable water peaking around 1.1-1.3 inches ahead of the system`s cold frontal passage. A second part of the system that would involve a changeover to snow flurries and perhaps light accumulating snow under a few snow showers would be dependent on how fast cold enough air could arrive in the lower levels before the secondary forcing advanced past the region and into the southeastern Great Lakes. Confidence is increasing in an ultimately strong to perhaps intense winter storm...yet there is much lower certainty that this system will come together fast enough and far enough southwest to bring much-needed heavier precipitation...and/or measurable snow. An updated glance at ensemble mean rain/snow probabilities for best 24- hour periods now indicate a 60-80% likelihood in a 24-hr period of 0.50+ inches of precipitation and a 20-40% likelihood of 1.00+ inches...with both of these POPs timed through the middle of the weekend. Snowfall probabilities denote a 20-30% chance of 1.0" snowfall in far northern portions of the CWA...and despite minuscule likelihoods of 3.0"+, the axis for this greatest potential would likely run in a SSW-NNE band through central portions of the state. Greatest snowfall chances are during the late weekend. Best confidence will perhaps be in breezy to gusty conditions through the entire weekend and into early next week, from first southerly, and then westerly directions...with gusts as high as 20- 35 mph across all of the region. Rather mild temperatures Saturday should trend to a return to seasonably cool readings through early next week.
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