848
FXUS63 KIWX 051857
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
157 PM EST WED NOV 5 2025
KEY MESSAGES
- WINDS 30 TO 35 MPH RELAX THIS EVENING.
- NORMAL TO ABOVE NORMAL TEMPERATURES INTO FRIDAY, WITH A TREND
TOWARDS SHARPLY COLDER TEMPERATURES THIS WEEKEND INTO EARLY
NEXT WEEK.
- A PERIOD OF RAIN SHOWERS IS EXPECTED LATE THURSDAY NIGHT INTO
FRIDAY. ADDITIONAL RAIN CHANCES EXIST LATE SATURDAY INTO
EARLY SUNDAY, POSSIBLY MIXING WITH A FEW SNOW FLAKES BEFORE
ENDING.
- LAKE EFFECT SNOW SHOWERS POSSIBLE SUNDAY NIGHT INTO MONDAY.
DISCUSSION
ISSUED AT 154 PM EST WED NOV 5 2025
BETWEEN THIS EVENING AND MONDAY EVENING, THE GENERAL PATTERN IS A
HIGH AMPLITUDE WAVE EMANATING FROM EAST ASIA ACROSS THE NORTH
PACIFIC AND INTO THE CONUS IN A COMBINATION BETWEEN A JET RETRACTION
AND A POLEWARD SHIFTED NORTH PACIFIC JET PATTERN. VARIOUS CYCLONIC
WAVE BREAKS OCCUR ACROSS THE EASTERN NORTH PACIFIC WHICH
ENHANCE THE RIDGE ACROSS THE WESTERN CONUS AND THIS ALSO BUILDS
THE TROUGH ACROSS THE EASTERN CONUS.
CLOSER TO HOME AND TO THE SURFACE, A DEPARTING MID LEVEL SHORTWAVE
TRANSITIONS TO SURFACE HIGH PRESSURE THIS AFTERNOON AND INTO
THURSDAY. THIS PROVIDES DRY, BUT COOLER WEATHER BEHIND A COLD FRONT
WITH HIGHS DROPPING BACK INTO THE 50S FROM THE LOWS 60S AND LOWS
FROM THE 40S BACK INTO THE 30S. ALL OF THIS IS MORE SEASONABLE
WEATHER FOR THIS TIME OF YEAR. WARM ADVECTION IS QUICK TO ARRIVE
THURSDAY AFTERNOON AND EVENING WITH GUSTS TO 20 MPH POSSIBLE SO A
RETURN TO THOSE AFOREMENTIONED 60S AND 40S IS LIKELY FOR FRIDAY.
CLOUDS AND EARLY-ARRIVING RAIN, ALONG WITH SOME 20 TO 30 MPH GUSTS-
STRONGEST SOUTH OF US-24, CHARACTERIZE OUR FRIDAY. RAIN IS LIKELY
OUT OF THE AREA DURING THE AFTERNOON.
850 MB THETA-E PLOTS INDICATE THE COLD AIR PUSH WAITS UNTIL SUNDAY/
MONDAY TIME FRAME. THERE IS ONE SYSTEM THAT IS ABLE TO PUSH EASTWARD
ALONG THE TEMP GRADIENT SATURDAY AND DEEPEN AS IT DOES SO. CURRENT
PROGRESSIONS KEEP THE INSTABILITY SOUTH OF THE AREA TO REMOVE ANY
SEVERE THREAT. IT APPEARS THE HEAVIEST OF THE RAIN THREAT ARRIVES
SATURDAY NIGHT, FORCED ALONG BY THE F-GEN BANDING/DEFORMATION AREA.
PERHAPS, IF THE COLD AIR RUSHES INTO THE AREA QUICK ENOUGH BEFORE
THE DRY ARRIVES, THERE COULD BE A BRIEF PERIOD OF SNOW SHOWERS THAT
MIX IN SUNDAY MORNING. THEN, AS A SHORTWAVE DIVES SOUTHWARD THROUGH
LAKE MI BY LATER SUNDAY, THERE'S ENOUGH LAKE ENHANCED INSTABILITY TO
POTENTIALLY SEE SOME INCREASED CLOUDINESS AND PERHAPS SOME LAKE
ENHANCED SNOW SHOWERS. THERE'S POTENTIAL TO GET A ROBUST LAKE
RESPONSE, ESPECIALLY AT NIGHT, BUT THE PIECES HAVE TO COME TOGETHER.
LOWS MONDAY MORNING DROP INTO THE LOW TO MID 20S WITH MID 30S FOR
HIGHS.
AVIATION /18Z TAFS THROUGH 18Z THURSDAY/
ISSUED AT 1255 PM EST WED NOV 5 2025
SURFACE COLD FRONT IS PUSHING ACROSS NORTHERN INDIANA THIS
AFTERNOON. WIND GUSTS HAVE BRIEFLY EXCEEDED 30 KNOTS WITH FROPA,
WITH FAIRLY STRONG PRESSURE RISES BUILDING IN BEHIND THE FRONT
AIDING IN THESE GUSTS. IN ADDITION, LOW LEVEL RH INCREASE IN
VICINITY OF THE FRONTAL ZONE HAS LED TO POCKETS OF MVFR CIGS.
THESE LOWER CIGS ARE INFLUENCING KSBN, BUT STILL SOME LOW TO
MEDIUM CONFIDENCE IN KFWA CIGS WITH POTENTIAL LOW CLOUDS STAY
ABOVE 3K FEET. AFTER 20 OR 21Z, THESE LOW CLOUDS SHOULD
DIMINISH AS LOW LEVEL DRY AIR ADVECTION BECOMES MORE PRONOUNCED.
WIND GUSTS WILL DIMINISH RAPIDLY TOWARD THE 23Z TIMEFRAME, WITH
LIGHT AND VARIABLE WINDS DEVELOPING OVERNIGHT INTO EARLY
THURSDAY MORNING AS SFC RIDGE AXIS APPROACHES. SOUTHERLY RETURN
FLOW WILL DEVELOP AGAIN FOR THURSDAY WITH SOME RETURN MID LEVEL
CLOUDS POSSIBLE.
FIRE WEATHER
ISSUED AT 323 AM EST WED NOV 5 2025
FIRE WEATHER CONCERNS DO LINGER FOR THE NEXT COUPLE OF DAYS PRIOR TO
THE LARGE SCALE SHIFT IN THE PATTERN. FOR TODAY, WARMER TEMPERATURES
AND HIGHER DEWPOINTS SHOULD KEEP RH VALUES 45% OR HIGHER. WINDS WILL
BE A LARGER CONCERN COMPARED TO YESTERDAY, STILL RESULTING IN A BIT
OF AN ELEVATED CONCERN FOR ANY BURNING OF LEAVES OR OTHER ITEMS. BY
THURSDAY, WINDS WILL HAVE DIMINISHED, BUT DEWPOINTS WILL MIX OUT
WITH MIN RH VALUES OF 30 TO 40%, POSSIBLY LOWER IN SOME AREAS. WILL
HOLD OFF ON ANY SPS ISSUANCE FOR NOW.
IWX WATCHES/WARNINGS/ADVISORIES
IN...NONE.
OH...NONE.
MI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EST THURSDAY FOR LMZ043-046.
DISCUSSION...ROLLER
AVIATION...MARSILI
FIRE WEATHER...FISHER
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