160
FXUS63 KIWX 160834
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
334 AM EST TUE DEC 16 2025
KEY MESSAGES
- MODERATING TEMPERATURES AND BREEZY AT TIMES THROUGH THURSDAY.
- PERIODS OF RAIN LATE WEDNESDAY NIGHT INTO THURSDAY, POSSIBLY
MIXING OR ENDING AS SNOW SHOWERS THURSDAY NIGHT INTO FRIDAY.
- WINDY AND BRIEFLY COLDER CONDITIONS ON FRIDAY.
- NEAR TO SLIGHTLY ABOVE NORMAL TEMPERATURES RETURN FOR THE
WEEKEND.
DISCUSSION
ISSUED AT 333 AM EST TUE DEC 16 2025
AN INCREASING LOW LEVEL FLOW, AHEAD OF A WEAK UPPER LEVEL TROUGH,
WILL ALLOW THE START OF ABOVE FREEZING TEMPERATURES. ALTHOUGH LOW
LEVEL TEMPS WILL CLIMB SEVERAL DEGREES ABOVE ZERO, A COMBINATION OF
A STRONG INVERSION AND THE WIDESPREAD SNOW PACK, WILL LIMIT THE
IMPACTS OF THE WAA. HIGHS SHOULD STILL REACH INTO THE MID 30S, BUT
HIGHER DEWPOINTS WHICH HELP RIPEN AND MELT THE SNOWPACK WILL BE
LAGGING. WINDS WILL INCREASE MID MORNING INTO THE EVENING HOURS AS
SOME MIXING TAKES PLACE OF THE HIGHER WIND FIELDS, BUT ONCE AGAIN
THE INVERSION WILL LIKELY KEEP STRONGER GUSTS IN CHECK. LOWS TONIGHT
WON'T DIFFER A BUNCH FROM TODAYS HIGHS AS CLOUDS HELP LIMIT THE
DROP. CAN'T RULE OUT A BIT OF FOG AND EVEN SOME FREEZING DRIZZLE IN
THE FAR SOUTH LATE TONIGHT AS LOW LEVEL MOISTURE INCREASED A BIT,
BUT HAVE LEFT ANY MENTION OUT.
A WARM FRONT WILL DEVELOP AND PUSH NORTH LATER WED INTO WED NIGHT,
BRINGING INCREASING LOW LEVEL TEMPERATURES AND DEWPOINTS THAT SHOULD
ALLOW FOR A MORE EFFECTIVE MELTING OF THE SNOWPACK (DEWPOINTS
USUALLY MID-UPPER 30S OR HIGHER). THESE FACTORS AND THE RELEASED
MOISTURE UNDER A STRENGTHENING INVERSION MAY SET THE STAGE FOR MORE
WIDESPREAD FOG AS WELL AS SOME DRIZZLE/LIGHT RAIN LATE WED NIGHT
INTO EARLY THURSDAY DESPITE THE INCREASED LOW LEVEL FLOW. LEFT
INCLUSION OF THIS TO LATER FORECASTS FOR THE TIME BEING. A BETTER
CHANCE FOR RAINFALL MOVES IN THURSDAY AHEAD OF THE COLD FRONT WHEN
MUCH STRONGER DYNAMICS ARRIVE TO SQUEEZE OUT ONE QUARTER TO ONE HALF
INCH OF RAIN. WINDS WILL INCREASE AHEAD OF THE FRONT WITH GUSTS UP
TO 30 MPH. HIGHS THURSDAY WILL TOP OUT WELL INTO THE 40S WITH A FEW
50S POSSIBLE ACROSS THE SOUTH, BEFORE THE FRONT SWEEPS THROUGH WITH
STEADILY FALLING TEMPERATURES THURSDAY AFTERNOON INTO THURSDAY
NIGHT (EASILY A 25 TO 30 DEGREE TEMPERATURES DROP). THE CAA WILL
ALLOW A BIT MORE EFFECTIVE MIXING OF WINDS TO THE SFC, WITH GUSTS OF
35 MPH OR SLIGHTLY HIGHER POSSIBLE. THE COLD AIR WILL SWITCH ANY
PRECIP TO SNOW (BETTER CHANCES IN MI WHERE SOME LAKE ENHANCED SNOW
SHOWERS COULD BRING SOME MINOR ACCUMULATIONS THURSDAY NIGHT.
A BLUSTERY DAY IS IN STORE FOR FRIDAY WITH HIGHS ONLY RECOVERING
INTO THE MID 20S AND MORNING WIND CHILLS NEAR ZERO. LAKE EFFECT
SHOULD BE SLOWLY WINDING DOWN AS THE CORE OF THE COLDEST LOW LEVEL
AIR QUICKLY BEGINS TO PULL AWAY WITH THE TROUGH. BY THE WEEKEND,
TEMPERATURES HEAD BACK INTO THE 30S AND 40S.
AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/
ISSUED AT 1212 AM EST TUE DEC 16 2025
VFR CONDITIONS EXPECTED TO PERSIST THIS PERIOD GIVEN BROAD WAA
AND MAIN WESTERLIES/SHORTWAVE TRACK WELL NORTH OF THE AREA. A
WEAK SHORTWAVE PASSING TO THE NORTH WILL SEND A WEAK FRONT
THROUGH THE AREA TUESDAY NIGHT. SOME MVFR STRATUS MAY DEVELOP
JUST AFTER 06Z BUT NO PRECIP IS EXPECTED. OTHERWISE, SSW WINDS
WILL INCREASE LATER TODAY AHEAD OF THAT FRONT WITH GUSTS OF
AROUND 20 KTS EXPECTED.
IWX WATCHES/WARNINGS/ADVISORIES
IN...NONE.
OH...NONE.
MI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 1 PM EST
WEDNESDAY FOR LMZ043-046.
DISCUSSION...FISHER
AVIATION...AGD
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