326
FXUS63 KIWX 052316
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
616 PM EST MON JAN 5 2026
KEY MESSAGES
- TRENDING WARMER THIS WEEK WITH HIGHS POTENTIALLY INTO THE 50S BY
THURSDAY AND FRIDAY.
- AREAS OF FOG AND DRIZZLE TUESDAY INTO TUESDAY NIGHT.
- PERIODS OF RAIN (70-90%) LATE THURSDAY INTO THURSDAY NIGHT.
- ADDITIONAL RAIN SHOWER CHANCES (50-60%) INTO FRIDAY AND
FRIDAY NIGHT.
DISCUSSION
ISSUED AT 113 PM EST MON JAN 5 2026
FOG, LOW STRATUS AND CHANCES FOR DRIZZLE/LIGHT RAIN WILL ENTER THE
FORECAST LATER TONIGHT INTO TUESDAY AS LOW LEVEL MOISTURE ADVECTS
INTO A FRONTAL WAVE TRACKING EAST THROUGH THE LOWER GREAT LAKES.
HEIGHT FALL CENTROID AND WEAK SFC REFLECTION TRACKING THROUGH
SOUTHERN MI SHOULD FOCUS HEAVIER PRECIPITATION NORTH OF THE AREA
WITH MORE OF A DRIZZLE OR VERY LIGHT RAIN SETUP LOCALLY GIVEN A
MORE SHALLOW MOISTURE PROFILE. HREF/NBM FOG PROBABILITIES ARE
RATHER IMPRESSIVE FOR AREAS OF FOG, ESPECIALLY NORTH OF THE US
24 CORRIDOR BETWEEN 14-21Z CLOSER TO THE SFC BOUNDARY/LOW WHERE
A PERIOD OF DENSE FOG APPEARS POSSIBLE. THIS LOW STRATUS, FOG
AND DRIZZLE MAY EVEN LINGER INTO TUESDAY NIGHT AS DRY/COLD
ADVECTION IN WAKE OF THIS SYSTEM IS WEAK WITH WRAP AROUND
MOISTURE PIVOTING THROUGH. SUBSIDENCE INVERSION COULD TRAP LOW
CLOUDS INTO AT LEAST THE FIRST HALF OF WEDNESDAY AS LIGHT RETURN
FLOW EVENTUALLY DEVELOPS ON THE BACKSIDE OF SFC HIGH PRESSURE.
CONFIDENCE CONTINUES TO INCREASE FOR 50 DEGREE PLUS HIGH
TEMPERATURES THURSDAY INTO FRIDAY AS SOUTHWEST FLOW DEEPENS IN
ADVANCE OF A WESTERN CONUS LONGWAVE TROUGH. A LEAD SHORTWAVE IN
THIS SOUTHWEST FLOW LOOKS TO BRING A GOOD SURGE OF MOISTURE
LATE THURSDAY INTO THURSDAY NIGHT WITH PERIODS OF RAIN. A
LEFTOVER SOUTHWEST TO NORTHEAST ORIENTED BOUNDARY FROM THE LOWER
GREAT LAKES TO THE MID MS VALLEY THEN KEEPS CLOUDS AND CHANCES
FOR LIGHT RAIN INTO FRIDAY. MODELS DIVERGE INTO FRIDAY NIGHT
AND SATURDAY WITH HOW INCOMING SHORTWAVE ENERGY WITHIN THE MAIN
UPPER TROUGH AXIS INTERACTS, AFFECTING THE POTENTIAL TRACK AND
DEVELOPMENT (OR NOT) OF A SFC CYCLONE INTO THE GREAT LAKES.
OPTED TO HOLD WITH THE NBM AS A RESULT WITH RAIN CHANCES FRIDAY
NIGHT (50-60%) TRANSITIONING TO COLDER TEMPERATURES AND CHANCES
FOR SNOW SHOWERS ON SATURDAY.
AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/
ISSUED AT 616 PM EST MON JAN 5 2026
VFR WILL PERSIST THROUGH MUCH OF THE OVERNIGHT HOURS. HOWEVER,
THE NEXT SHORTWAVE CROSSING THE REGION ON TUE WILL BRING A
SUBSTANTIAL SURGE OF WARM/MOIST AIR ADVECTION BEGINNING 09-12Z.
A VERY QUICK TRANSITION TO LIFR CEILINGS IS EXPECTED GIVEN THE
SURGE OF WARM/MOIST AIR OVER COLD GROUND, THOUGH THE EXACT TIME
IS STILL SOMEWHAT UNCERTAIN. LIFR WILL BE LOCKED IN NO LATER
THAN 13Z AND WILL PERSIST THROUGH MUCH OF THE DAY WITH JUST SOME
MINOR IMPROVEMENT BY LATE AFTERNOON AS SURFACE LOW EXITS AND
WESTERLY WINDS/MIXING INCREASE SLIGHTLY. VISIBILITIES MAY ALSO
BRIEFLY DIP BELOW 1/2SM AT KSBN LATE TUE MORNING BUT CONFIDENCE
IS TOO LOW TO INCLUDE IN THE TAF AT THIS POINT AND WILL HOLD
WITH PREVAILING 3/4SM.
IWX WATCHES/WARNINGS/ADVISORIES
IN...NONE.
OH...NONE.
MI...NONE.
MARINE...NONE.
DISCUSSION...STEINWEDEL
AVIATION...AGD
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