143 

FXUS63 KIWX 310528

AFDIWX



Area Forecast Discussion

National Weather Service Northern Indiana

1228 AM EST Wed Dec 31 2025



.KEY MESSAGES...

- The first of two fast-moving clipper systems will impact the

  area tonight, bringing widespread light snow with the best

  chance of accumulations mainly north of US-30. There is a

  50-70 percent chance of at least 3 inches of new accumulation

  across Berrien County MI this evening and overnight. 



- A second clipper will impact the area Wednesday afternoon

  through early Thursday morning. A general 1-3 inch snowfall is

  expected from this system, though localized snow squalls are

  also possible which could contribute to locally higher

  accumulations. 



- Trending drier later in the week through the weekend, but

  seasonably cold temperatures persist.



&&



.UPDATE...

Issued at 607 PM EST Tue Dec 30 2025



Per radar imagery, surface observations, and area webcams, 

light snow is beginning to overspread the area this evening.

Visibilities are between 5-7 miles. This clipper system will 

bring light snow to the area tonight and early overnight. Snow 

is expected to taper off by daybreak for much of the area, 

although light lake effect snow showers persist Wednesday 

morning near Lake Michigan. Will likely handle the snow tonight

with an SPS if needed (not a Winter Weather Advisory). Watch 

out for reduced visibilities and slick roads overnight and for

the Wednesday AM commute. Snow accumulations will be between a 

trace to 1" overnight (1-3" in areas with residual lake effect 

tomorrow morning).



&&



.DISCUSSION...

Issued at 1255 PM EST Tue Dec 30 2025



An unsettled weather pattern will persist through mid-week with the 

primary focus being on two clipper systems, both of which offering 

two brief windows of additional minor snowfall accumulation. A few 

lingering lake effect snow showers have finally begun to diminish 

early this afternoon, but expect this lull will be fairly short 

lived as a fast moving short wave and attendant mid-level vort 

max tracks across the western Great Lakes, giving way to 

widespread light to moderate snow w/ the best chance for 

accumulations north of US-30 with the highest amounts favored 

over Berrien County MI with 50-70 percent probabilities of at 

least 3 inches per the latest HREF suite. Given the relatively 

short residence time of the strongest dynamic support, opted not

to issue any headlines at this time but certainly cannot rule 

out the need for a possible Winter Weather Advisory this evening

into the overnight hours. A second, markedly stronger 

disturbance arrives mid/late Wednesday with a coupled 120- 130 

knot H25 jet helping contribute to a few strongly forced snow 

bands along the surface boundary, along with some lake 

enhancement as well. Very steep low-level lapse rates suggest 

sufficient instability for potential snow squall activity, so 

will need to monitor for this as well. An general 1-3 inch 

snowfall can be expected with this next wave. Otherwise, 

continued cold as the parade of clippers will continue to 

provide reinforcing shots of cold air, keeping H85 temperatures 

between -6 and -12 deg C and surface temperatures below 

freezing.



&&



.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...

Issued at 1227 AM EST Wed Dec 31 2025



Two pieces that deserve attention over the next 24 hours. The 

shortwave from the first piece provides 1 inch or less of snow at 

FWA and 1 to 2 inches of snow at SBN. SBN has had IFR visby reports 

for a couple of hours up to this TAF issuance, but model guidance 

allows for moderation of VISBY a couple hours into this TAF. MVFR 

CIGs are expected to prevail for a good portion of this TAF, 

however, cannot rule out some periods of IFR within some of the 

stronger bands of snow. 



Hot on its heels, a second, much more vigorous shortwave passes by 

much more north of the area than the first wave, but it actually 

causes more snow to fall. MVFR CIGs look to continue, but IFR and 

perhaps LIFR VISBY looks to be the main hazardous condition to 

target.



Winds slowly veer from west southwest to west northwest over the TAF 

period staying above 10 kts sustained and having times of gusts 20 

to 25 kts, especially this afternoon and evening. 



&&



.IWX WATCHES/WARNINGS/ADVISORIES...

IN...None.

OH...None.

MI...None.

MARINE...Small Craft Advisory until 4 PM EST Thursday for LMZ043-046.



&&



$$



UPDATE...Johnson

DISCUSSION...Hammer

AVIATION...Roller