817
FXUS63 KIWX 081133
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
633 AM EST Mon Dec 8 2025

.KEY MESSAGES...

- Cold wind chills tonight from -1F to +5F.

- Seasonably mild temperatures with periods of snow and a rain
  mix into early Wednesday. Travel impacts appear limited.

- Turning very cold again late this weekend with highs only in
  the teens.

&&

.DISCUSSION...
Issued at 415 AM EST Mon Dec 8 2025

The duration of the cold airmass has reached day 11 today (since
November 27th). The Fort Wayne temperature has averaged only
18.8 degrees so far this month with has been an incredible 15.5
degrees below normal. The ENSO pattern is "...transitioning
from a weak La Nina..." into 2026 per CPC update. Given this
pattern and given persistence, another arctic air intrusion is
expected to arrive Wednesday. The temperatures early this
morning have been dipping below zero once again. With this
pattern and airmass in place, the forecast area is on the
threshold of this next cold intrusion. RWIS data/Traffic Wise
indicated pavement temperatures were in the teens. Given the
low sun angle for December, the incredibly large "cold anomaly"
ongoing ground temps and current snow cover, any snow or ice
melting on roads should be limited through Tuesday.

These cold ground conditions will provide an interesting
unfolding of the travel conditions Tuesday night into Wednesday
as surface air temperatures rise briefly above freezing. Some
icing is possible on roads before the pavement temperatures rise
briefly above freezing on rural and secondary roads. Readings
should drop below freezing Wednesday evening and stay well
below freezing into early next week. Chances form mainly light
snow will persist through the weekend as several weak
disturbances top the upstream ridge and race southeast into the
forecast area per 00Z GFS. Heavy snow is not expected, but there
could be travel issues given the light to possibly moderate
snow falling on secondary and rural roads.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 620 AM EST Mon Dec 8 2025

VFR Conditions expected at the terminals through the period,
with mainly mid-high level clouds to contend with until late
tonight at KSBN when the next system approaches the area. E-NE
winds this morning shifting to the S-SW late tonight, with a
tightening pressure gradient towards the 6-12z timeframe-
especially at KSBN. SSW winds at around 13kts will may
intermittently gust to around 21kts. Most of the guidance holds
off on snowfall until after 12z, however a few of the high res
solutions suggest around 10-12z. Have a prob 30 group for 9z
onward, with ceilings down to around 3500ft possible (quickly
deteriorating to MVFR beyond 12z). KFWA will see a slight uptick
in winds towards 8-12z, but MVFR ceilings won`t reach the
terminal until probably 15z Tue AM (just beyond the TAF period).


&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...None.
OH...None.
MI...None.
MARINE...Small Craft Advisory from 10 PM this evening to 10 PM EST
     Tuesday for LMZ043-046.

&&

$$

DISCUSSION...Skipper
AVIATION...MCD