703
FXUS63 KIWX 190603
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
103 AM EST FRI DEC 19 2025
KEY MESSAGES
- WINDY WITH LIGHT RAIN OR FREEZING DRIZZLE CHANGING TO SNOW
OVERNIGHT AS TEMPERATURES FALL INTO THE TEENS BY MORNING.
THERE MAY BE SLICK SPOTS ON THE ROAD.
- MILD AND MAINLY DRY TUESDAY THROUGH CHRISTMAS. HIGHS IN THE
40S TO LOWER 50S.
DISCUSSION
ISSUED AT 1208 PM EST THU DEC 18 2025
MILD AIR HAS SPREAD NORTH ACROSS THE ENTIRE FORECAST AREA WITH
TEMPERATURES IN THE 40S AND 50S. BANDS OF SHOWERS WILL CONTINUE TO
DEVELOP THIS AFTERNOON OVER AND TO THE WEST OF THE FORECAST AREA.
THESE SHOWERS WERE ASSOCIATED WITH A DEEP 986MB LOW OVER THE
ARROWHEAD REGION OF MN (FAR NORTHEAST MN). FORECAST CHALLENGES
INCLUDE TIMING OF THE COLD FRONT, TYPE IF ANY WIND HEADLINES,
ANY WINTRY MIX OF PRECIPITATION AND THE POTENTIAL FOR A FLASH
FREEZE. THE COLD AIR UPSTREAM HAS BEEN LAGGING SOMEWHAT BEHIND
THE SURFACE FRONT WHICH SHOULD HELP LIMIT ANY CHANCES FOR
FREEZING PRECIPITATION.
ALL INDICATIONS POINT TOWARD AN EVENT BELOW WIND ADVISORY CRITERIA.
THE STRONGEST WIND GUSTS SHOULD BE FROM THE WEST AT 20 TO 30 MPH
WITH GUSTS TO 45 MPH, ESPECIALLY WITH THE PASSAGE OF THE FRONT. DO
NOT PLAN TO ISSUE A WIND ADVISORY, BUT RATHER HANDLE THIS EVENT WITH
AN SPECIAL WEATHER STATEMENT AS THE FRONT NEARS. ONGOING UPSTREAM
OBSERVATIONS AND GFS LAMP GUIDANCE SUPPORT THE ABOVE. LOWS TONIGHT
ARE EXPECTED TO FALL INTO THE TEENS WITH HIGHS FRIDAY ONLY AROUND
25. THE LATEST TIMING FOR THE COLD FRONT IS AROUND MIDNIGHT EST
AT SOUTH BEND AND ABOUT 2AM EST OVER NORTHWEST OHIO.
UPSTREAM TELECONNECTIONS STRONGLY FAVOR A BRIEF INTRUSION OF
COLD AIR FOLLOWED BY MILD AIR RAPIDLY RETURNING TO THE AREA.
HIGHS FRIDAY SHOULD BE NEAR 25 - BUT HIGHS SATURDAY SHOULD BE
15 TO 20 DEGREES WARMER (LOWER 40S). AFTER A BRIEF ARCTIC
INTRUSION SUNDAY, THE MILD PATTERN WILL RETURN WITH A VENGEANCE.
THE LATEST GFS SHOWS BASICALLY A HIGHLY BLOCKED PATTERN IN THE
HIGH LATITUDES WITH UPPER RIDGES OVER THE ALEUTIAN ISLANDS,
CENTRAL AND EAST CONUS, AND OVER ICELAND. THE GFS 500 MB HEIGHT
ANOMALY IS VERY INDICATIVE OF THIS MILD PATTERN WITH BLOCKS
EXCEEDING 400 METERS (PER GFS OVER ALASKA AND ICELAND).
AVIATION /06Z TAFS THROUGH 06Z SATURDAY/
ISSUED AT 642 PM EST THU DEC 18 2025
MVFR TO IFR CONDITIONS TO START THE PERIOD, EVENTUALLY IMPROVING
TO VFR LATE THIS AFTERNOON INTO THE OVERNIGHT. KFWA MAY BRIEFLY
SEE A DROP TO IFR CEILINGS/VISIBILITIES THE NEXT COUPLE HOURS
WITH EITHER LIGHT FREEZING DRIZZLE/SNOW OR A MIX (PER
SURROUNDING OBS), WITH WESTERLY WINDS PICKING UP ONCE AGAIN.
GUSTS UP TO AROUND 29KTS ARE EXPECTED THROUGH THE NIGHT. AT KSBN
CONDITIONS ARE LIKELY TO REMAIN MVFR PER MOST OF THE GUIDANCE
AND SURROUNDING/UPSTREAM OBSERVATIONS. AS OF THIS WRITING, THE
LAST OBSERVATION RECEIVED WAS AT 2:54Z, SO CANNOT BE CERTAIN IF
CEILINGS ARE SIMILAR TO SURROUNDING OBS. WSW WINDS SHIFT WNW,
WITH POTENTIAL FOR FLURRIES OR LIGHT SNOW THROUGH THIS AFTERNOON
AS A SHORTWAVE MOVES THROUGH. IT'S POSSIBLE THE SNOWFALL REMAINS
FURTHER NORTH, SO KEPT A MORE OPTIMISTIC FORECAST IN TERMS OF
VISIBILITY/CEILINGS (IN ALIGNMENT WITH ALL OF THE GUIDANCE).
IWX WATCHES/WARNINGS/ADVISORIES
IN...NONE.
OH...NONE.
MI...NONE.
MARINE...GALE WARNING UNTIL 1 PM EST THIS AFTERNOON FOR LMZ043-046.
DISCUSSION...SKIPPER
AVIATION...MCD
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