From Storms To Snow; Active Week Ahead…
Our week-ahead outlook is focused on everything from storms to a return of unseasonably cold conditions and snow. As a strong storm system lifts north into the Great Lakes Sunday, it’ll swing a cold front through the Ohio Valley Sunday night. This will sweep the briefly milder air out of here and allow much colder air to settle back into the region through the balance of the week ahead. With the colder air in place, snow chances will return, as well. First up is a clipper system late week followed by the potential of something “more important” next weekend…
I. Steady rains will come to an end this morning and we’ll replace the soaking rain will widely scattered showers and embedded thunder later this afternoon and evening. Several dry hours can be expected for the majority of central Indiana beforehand. While the greatest threat of strong to severe storms will remain to our west in IL, we’ll keep an eye out for the potential of a gusty storm or two- especially west of the I-65 corridor later this evening.
II. Highs today will come tonight (mid-to-upper 50s) ahead of the cold front. Once the front moves through, colder air will return for the second half of the weekend. As wrap-around moisture combines with the colder air, light snow showers will develop late Sunday night into Monday morning (shown below). This won’t be a huge deal.
III. The next item of interest will come from a clipper system Thursday. This won’t only serve up another round of light snow, but also help to reinforce the unseasonably cold air. Highs will return to around freezing to close the week with lows in the 20s.
IV. That leads us to what comes next weekend. While it’s still far too early for any sort of specifics, we’ll simply say to keep a mental note in the back of your mind for the potential of a more disruptive winter event coming out from the southern Plains into the Ohio Valley. We’ll certainly have to fine tune things and “hone in” as we progress through the upcoming week. From this distance, prospects range from nothing more than a light snow to a “plowable” storm. Unlike this weekend’s storm, there will be a limit to how far north next weekend’s storm will be able to track…
Additional rainfall totals of 1″ to 2″ with locally heavier amounts are a good bet in that Monday night – Tuesday time frame.
While we’ll certainly turn colder behind this storm system, the true early season push of arctic air will wait a couple of days to arrive- Thursday afternoon into Friday. Not only will this be the coldest air of the season (lower-middle 20s Friday morning and likely colder next Saturday), but the first flakes of the season are also likely to fly across central Indiana to wrap up the work week. Furthermore, 
Don’t look now, but more “fun and games” await the following week…
II. Wet Halloween: A cold front will approach the state Tuesday evening into our Halloween. Widespread rain is expected Wednesday, BUT the silver lining may be that the bulk of precipitation will be shoved to our southeast before most trick-or-treaters take to the streets.
III. Chilly Open To November: Reinforcing chilly air will blow into town behind the cold front and set the stage for an unseasonably chilly open to November. Generally, lows will fall into the middle 30s and highs will top out in the upper 40s for the first few days of the month.
IV. Raw Saturday: It’s a “rinse and repeat” scenario as next weekend opens raw and wet thanks to a new storm system moving through the region. Gusty showers and unseasonably cool temperatures can be expected Saturday. Note the possibility of wet snow to fall on the northern periphery of the storm system through IA, MN, and WI. (Signs of the times).
V. Wet Pattern: After a long stretch of dry weather through the balance of October, a big shift in the pattern is taking place now and will continue to promote well above normal rainfall as we move through the first couple weeks of November. In some cases, the upcoming (10) days alone may yield 3″ to 4″ of rain in some areas of the region.
A cold front will sweep through the region Wednesday evening and will lead to a better chance of more concentrated showers and thunderstorms for our hump day. Precipitable water values (PWATs) will approach 2″ Wednesday afternoon which is almost unheard of by October standards. As a result, a couple of the storms may be accompanied by locally heavy rainfall.
Winds of change will be blowing in earnest Wednesday night and Thursday morning and a legit fall feel will greet us out the door! Most of central Indiana can expect temperatures to be falling into the 40s Thursday morning along with a nice northwest breeze.
Longer term, a new storm system (including remnant moisture from Sergio) is expected to impact our weekend weather. We’ll trend our forecast wetter with reviewing some of the latest data. Sunday appears to be the wettest day.
An even more impressive push of fall air will follow on the heels of Sergio’s remnants early next week, including the potential of frost for more of the Ohio Valley, including central Indiana.