It's going to be a wild weather pattern for Indiana as we approach Christmas Day of 2025!

We're going to get snow tomorrow night, Thursday (10/11) and then again on Saturday (10/13). The Polar Vortex will be here Saturday through Monday. After that it slowly warms up. 

Currently there is a Winter Weather Advisory out for central Indiana for Thursday night. My prediction and /or guess is 1-3 inches just based on hi-res models. The National Weather Service is saying that we could get 2-6 inches. 

The cold polar air will be brutal this weekend. Please be careful going out to watch the IU v. Kentucky basketball game. GO HOOSIERS! Windchills will be worse.

It looks like the pattern will be split during Christmas week. I'm seeing everything from an ice storm to a snow storm to tornadoes and even heavy rain. Check out this bizarre scenario:

Let's hope this doesn't happen. We like snow, not ice right?

Here is the long term discussion from the National Weather Service:

.LONG TERM (Friday night through Wednesday)...
Issued at 312 PM EST Wed Dec 10 2025

Another round of snow is likely on Saturday. An upper level trough,
surging Arctic air, weak low pressure, and an upper level jet will
all combine to provide forcing across central Indiana on Saturday.
Moisture will have not been cleared out from the previous system,
so this forcing will have moisture to work with.

The result will be snow spreading across the area from west to east
Saturday, ending later in the day (potentially into the evening).
Some differences remain in guidance on the amounts and location of
the higher amounts.

At the moment, another 1 to 3 inches of snow look to be a good bet
for a large portion of the area.  Higher amounts are possible,
especially with some frontogenetical forcing in the area potentially
leading to banding. (Blended guidance`s 24 hour snowfall 25th
percentile is around 1 inch with 75th percentile 4-5 inches in
locations with the highest totals).

Arctic high pressure will build in for Sunday and Monday, providing
bitterly cold conditions. Air temperatures will likely be below zero
across portions of the area early Sunday and early Monday. Before
the center of the high moves nearby, winds will make it feel even
colder Saturday night into Sunday morning. There is the potential
for wind chills from -10 to -20, which would require headlines. Will
continue to monitor closely as the location of the deepest snow
cover will have an impact on temperatures.

The high will provide dry weather through Tuesday. As the area gets
on the western side of the high, warm advection will return
temperatures into the 30s for Tuesday and potentially even the 40s
on Wednesday. A system could bring some precipitation by Wednesday,
but it looks to be just rain if temperatures warm as expected.

 

Who wants sunny and 60 degrees for Christmas?

It probably wont happen but this one model interpretation.

Just say NO!

 

Back in the 1990's people just called it a rain-snow mix.

That's what it is for southern Indiana on Saturday. 

Winter Storm Watches are posted up to the Illinois / Indiana border

The weather models have been very unpredictable with this storm. The last 48 hours showed central Indiana getting a rain / snow mix while the main part of the snow went north of Indianapolis. The latest models have trended southwards. Even Louisville Kentucky might see a little snow. I would expect that some kind of an advisory or alert will be posted for our area right as the the turkey is done, or 6:00pm.

Winter Storm Watches are starting to go up in Iowa so what does this mean for Indiana?

The computer models have been all over the place. At this point, if I had to guess, I would say the northern third of Indiana gets a Winter Storm Warning sometime on Friday. The middle third of Indiana gets a Winter Weather Advisory and the southern third of Indiana gets a rain /snow mix. And all rain south of I-64. That's my best guess. Stay tuned...

A wild and complex pattern is emerging after Thanksgiving.

I don't think anyone knows what the weather will be like this coming weekend. If you really want to understand how complicated it is, you can read what the National Weather Service is thinking.
________

.LONG TERM (Tuesday through Sunday)...
Issued at 257 AM EST Mon Nov 24 2025

An active weather pattern continues next week with numerous systems
bringing large temperature swings, rain, and windy conditions to the
state.

Tuesday...

Weak troughing lifts northeastward into the Great Lakes Monday night
while a jet streak overhead and an increasing low and mid level jet
bring moisture northward into the state. The best moisture
convergence is currently expected to remain south of central
Indiana, however, modest isentropic lift within the strengthening
LLJ support widespread rainfall early Tuesday morning with lingering
showers through the day. Mid-level moisture will be minimal
throughout, but strong upper level support and saturation above
500mb could lead to high rain rates at times. Generally, QPF totals
for this event are likely to remain below 1 inch with most areas
below 0.5 inches, highest rainfall amounts likely south of I-70.

Southwesterly flow persists behind this initial system as a much
stronger trough and associated low develop over the Northern Plains
and Upper Great Lakes. With the cold air locked up north behind the
next system and a warmer airmass still overhead, high temperatures in
the mid 50s to low 60s are expected despite clouds and showers.

Wednesday through Friday...

A significant pattern shift arrives the day before Thanksgiving as a
strong trough to the north and associated front usher in an arctic
airmass over the entire region. The front pushes through the state
early Wednesday morning, but the lack of moisture behind the
pressure trough passage earlier on Tuesday will limit rain shower
coverage along the boundary. Despite only isolated to scattered
showers signifying the front, the temperatures disparity along this
frontal axis will be large, with temperatures quickly falling 10-15
degrees within a few hours from the low 50s to upper 30s early
Wednesday morning.

Steepening low level lapse rates as much colder air advects in aloft
along with a strong 30-40 kt low level jet will make for a cold and
windy day. West northwesterly winds 15-25 mph with gusts over 35-40
mph are likely...stronger gusts may be possible. Lower confidence in
the temperature forecast for Wednesday as guidance may not be
handling the set up well as temperatures may not follow a typical
diurnal pattern. High temperatures may be reached early in the day
before the front, with steady or falling temperatures in the 30s
during the afternoon and evening. Wind chill values will likely
remain below freezing all day, dropping into the teens by Wednesday
night. Not too concerned with wintry weather at the moment as enough
dry air should be advecting in, limiting snow showers within the
cyclonic northwest flow pattern; however would not be surprised to
see on and off flurries.

Winter-like temperatures and breezy conditions persist Thanksgiving
and Friday as strong northwesterly flow keeps an arctic airmass
entrenched over the region. While conditions will be fairly dry,
high temperatures may struggle to get above the freezing mark while
wind chill values stay in the teens and 20s.

Next Weekend into Early December...

Confidence is increasing in a significant storm system and strong
baroclinic zone developing next weekend and into the first week of
December, setting the stage for an active period with widespread
precipitation and large temperature swings. Long range guidance has
been consistent in showing an active southwesterly subtropical jet
across the Central and Southern CONUS in response to a sharpening SW
to NE temperature gradient setting up from the Plains to the Great
Lakes. This classic winter-time pattern can bring widespread heavy
rain, snow, and storms to a large portion of the CONUS. While
confidence is low on the specifics and exact evolution of mesoscale
and synoptic scale features, confidence is increasing in this
pattern developing with Central Indiana within or near the main
storm track.

The set up for Saturday is fairly complex as longer range guidance
indicates a weak trough approaching from the northwest within the
northern branch of the jet, while the subtropical jet increases
southwesterly flow aloft through the Ohio Valley. Interactions from
both the northern and southern branches of the jet can result in
favorable set up for snow. Flow becomes southerly going into
Saturday as a surface low tracks across the Midwest into the Great
Lakes with sufficient moisture advection northward with a 30 kt LLJ
overhead. Deeper cold air in place from the previous few days may
take a while to retreat northward, setting the stage for a quasi
overrunning event where warmer moist air overruns a cold, denser
airmass at the surface. While confidence is lower in the finer
details of this set up and the overall evolution and track of
synoptic features, this will be a system to watch as any snow this
time of year can cause major travel impacts. Keeping snow in for the
first half of the day Saturday, transitioning to a rain/snow mix
during the afternoon, then all rain by the evening. This is an
initial forecast and details will likely change and be fine tuned
over the next several days.

The active pattern is expected to persist into the following week
with additional waves of precipitation tracking through the state
and large temperature swings. We will be monitoring this timeframe
closely and updating the forecast accordingly as confidence
increases on timing, track, and impacts.

Rain then storms them snow and then the polar vortex.

There's a lot of rain coming this week. Storms are possible tomorrow. But the big story is that the Polar Vortex is on the move and will be arriving here by the end of next week. Snowstorms are starting to show up again. Something will likely happen between November 28 and December 5.

Enjoy the warmth for now because winter will return after Thanksgiving.

As you might already know it's going to be nice and warm this weekend. The warmth will likely continue into next week as well.  Beyond that, it looks like the polar vortex will start moving out of Siberia and making its way around to America by the last week of November. 

As a general rule, if it's warm in Alaska then it will be cold in Indiana. If it turns cold in Alaska then it will be warm in Indiana. 

There's  some other very nerdy stuff involved like the Bering Sea Rule, the Recurring Rossby Wave Train and then there's Sudden Stratospheric Warming. Anyone can look those up if they are interested but the main point is to look out for the polar vortex to come to Indiana just after Thanksgiving.

Enjoy the Northern Lights if you can see them and post pictures if you have them.

#BOTS! (Bring on the snow)

It's been rather boring in the weather department lately. The same goes for this week with mostly sunny skies, highs in the 60's and lows in the 40's. This week should be perfect for fall foliage so take some pictures and post them.

Before we see any snow, usually there is a severe weather event before the pattern changes to a colder one. That looks like it might happen next week. 

The highly respected European computer model has a line of storms approaching on Friday and Sunday. After that is has snow flurries on Monday.

The American GFS model has the opposite. It has snow this coming Sunday and a tornado outbreak the following Sunday, November 16.

Nonetheless, expect a pattern change next week along with the threat of severe weather. 

A Frost Advisory and a Freeze Watch for Monroe County Indiana.

This is it! This will mark the official end to the growing season.

Melissa could cause trouble by Friday. She should be a full blown hurricane by then but her path is undetermined.

Daylight Saving Time ends on Sunday, November 2.

We might see snow between November 4 and November 11.