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.
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