South Bend, Indiana 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

632
FXUS63 KIWX 211120
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
620 AM EST Thu Nov 21 2024

.KEY MESSAGES...

- Snowshowers will become more widespread through the day,
  mixing with rain in some areas this afternoon. Highest snow
  accumulations west of Indiana 15.

- Some lake effect rain showers are possible Friday, but overall
  a quiet weekend appears to be in store.

- Rain chances return early next week.

&&

.DISCUSSION...
Issued at 417 AM EST Thu Nov 21 2024

Generally light snowshowers are impacting many areas as the
pocket of colder air, combined with a disturbance clipping SW
areas, aid in increased lift. Thus far no impacts have been
reported with some spots likely seeing a dusting or maybe tenth
of snow. The exception may be closer to Lk MI where somewhat
heavier showers existed as lake enhancement was helping. QPF
amounts from KBEH have not been overly impressive so far, with
MDOT plow and stationary cameras showing maybe a few tenths to
locally an inch.

The upper level low is slowly working across central Lower MI
with the sfc low moving across the eastern UP of MI. Models have
been pretty pronounced on coverage, intensity and QPF potential
as the low drops south down the heart of Lake MI today, reaching
NW areas later this morning (16Z or so) and then existing the
south near 00Z Fri. Concerned that QPF may be way overdone given
a close look at observations in the UP where the heaviest
precip is supposed to exist per the models. The sfc low will be
slowly weakening as it drops south, but still have a fair amount
of energy and moisture accompanying it. The biggest changes for
now was to limit the eastern edge of the highest pops as the
bulk of the precip looks to remain along/west of Indiana 15. QPF
amounts were lowered some, but not substantially for now,
yielding slightly lower accumulations west (still in the 1 to
maybe 2 inch range). Model trends have also showed somewhat
higher afternoon temps with even a degree or 2 warmer impacting
the overall accumulation. As the area of precip comes through,
expect reduced visibility and in areas that see snowfall,
accumulations would occur on grassy and elevated areas. Road
temperature forecasts suggest readings in the 40s during the
peak of the event, meaning roads should be wet. While it will be
breezy today the sfc low track will push the strongest pressure
gradient west of the area (where wind advisories have been
issued across IL). Strongest winds for our area will be both
ahead of and behind the low, with gusts of 35 to maybe 40 mph in
the west.

Significant changes made for tonight to trend much drier and
also colder as subsidence arrives in the wake of the low and
maybe even some breaks or thinning of the clouds. Lows will be
in the upper 20s NE to near freezing west, so any wet roads
could freeze in spots (although suspect minimal if any impacts).
Lake effect showers will be possible on Friday as another
disturbance drops south. Thermal profiles support all rain with
overall intensity likely not very high as Delta Ts are closer to
12 to 14 C (enough for lake effect, but not ideal for heavier
precip). In addition, inversion heights will be lower (7 to
8Kft).

With focus on the next 24 to 36 hours, little was modified in
the extended period (Sat-Thu) with the weekend likely dry and
warmer (above normal), followed by a northern stream wave that
may bring some rain or snow chances mid to late week.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 620 AM EST Thu Nov 21 2024

SCT, mainly MVFR, snow showers will continue during the next
few hours until primary vort max and surface low dive south into
the area this afternoon. This will primarily impact KSBN with
visibilities below 1SM likely for several hours in the 16-22Z
window. Lesser impacts anticipated at KFWA but periods of IFR
are possible there as well. Improvement anticipated during the
evening hours with return to VFR possible. However, lake effect
stratus will build again by early Friday with MVFR conditions
likely once again.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...None.
OH...None.
MI...None.
MARINE...Small Craft Advisory until 7 AM EST this morning for LMZ043-
     046.
     Gale Warning until 1 AM EST Friday for LMZ043-046.

&&

$$

DISCUSSION...Fisher
AVIATION...AGD