We are tracking two systems that could bring snow to central Indiana. The second of which could bring the first measurable snow to Indianapolis is nearly seven months.
The first system will slide through north-central Indiana beginning. It will start along the Illinois/Indiana state line around 4am and move to the northeast. It should exit central Indiana by 8am.
There remains some question as to how much, if any, of the precipitation reaches the ground due to dry air in the lower levels of the atmosphere. You may look at the radar in the morning and see snow, then look outside and see nothing due to the moisture evaporating as it falls to the ground.
Don’t expect much in the way of accumulation from this. A few locales could get a tenth of an inch or two, but a dusting is more likely if any accumulates on the ground.
THE MAIN COURSE
Moisture is projected to spread in to central Indiana Monday afternoon and in to the evening. Computer models suggest precipitation will begin in the form of rain after 4pm. As temperatures near the surface drop, rain will begin to mix with snow, before changing over to all snow.
Like the “appetizer” round, it looks like we may be fighting dry air in the lower levels of the atmosphere. Computer models suggest dry air will be located from the surface up to 7,000ft until 5pm to 7pm Monday. That means precipitation that falls may evaporate prior to reaching the ground. Similar to Monday morning, the radar may be indicating rain/snow but it may not be reaching the ground.
As the precipitations falls in to the dry air, the atmospheric column will eventually saturate enough to support moisture reaching the ground.
The animation above shows a computer model’s projection of radar/satellite imagery Monday through Tuesday morning. Notice, after 1am Tuesday the snow begins to break up as the system moves east. Early Tuesday morning any snow showers left will be very scattered.
At this time I think snow will hold off falling during the evening commute. However, if you are out later Monday night, you could encounter some roadways with minor amounts of snow on roadways.
HOW MUCH SNOW
When I create the snow forecast for central Indiana I use over 200 calculations and data from 28 computer models. I then run the numbers through a matrix to help suggest how much snow could accumulate.
Parts of central Indiana may receive an inch of snow from Monday evening through Tuesday morning. A 28-computer model average suggests 0.4″ for Indianapolis. Here are some other locations around central Indiana.
- Bloomington: 0.2″
- Columbus: 0.1″
- Crawfordsville: 0.8″
- Kokomo: 0.6″
- Lafayette: 0.6″
- Muncie: 0.5″
- Peru: 0.7″
- Shelbyville: 0.2″
NORMAL FIRST MEASURABLE SNOW
November 22 is the normal first snow in Indianapolis over the previous 30 years.
WEEK REMAINS BELOW NORMAL
Cooler than normal temperatures will be the rule for the week ahead. If we do have a small amount of snow on the ground, Wednesday morning could be cold. Temperatures are forecast to drop to the teens.
We are going to keep an eye on Thursday in to Friday. Computer models are picking up on an upper-level low pressure area in the Mississippi River Valley moving northeast towards the Ohio River Valley. This could bring rain to the area, but with cool temperature near the ground that could cause some problems for what type of precipitation ends up on the ground. That is something we will get resolved as we get closer to it. Stay tuned!