188
FXUS63 KIWX 161742
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
142 PM EDT WED OCT 16 2013
.SYNOPSIS...
ISSUED AT 1041 AM EDT WED OCT 16 2013
SKIES WILL BECOME CLOUDY THIS AFTERNOON...WITH SHOWERS POSSIBLE
NEAR LAKE MICHIGAN. HIGH TEMPERATURES WILL RISE INTO THE UPPER 50S
AND LOW 60S TODAY. LOWS TONIGHT WILL DIP INTO THE LOW TO MID 40S.
RAIN CHANCES WILL INCREASE EARLY TOMORROW MORNING AND INTO THE
AFTERNOON AS ANOTHER SYSTEM MOVES THROUGH THE REGION. HIGHS
ON THURSDAY WILL TOP OUT IN THE MID 50S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 454 AM EDT WED OCT 16 2013
THE COLD FRONT HAD ALMOST CLEARED NORTHEAST INDIANA EARLY THIS
MORNING...WITH MUCH DRIER AIR AND A DRY SLOT SPREADING ACROSS THE
WESTERN PORTION OF THE FCST AREA. LINGERING SHOWERS OVER THE FAR
SOUTHEAST INCLUDING THE LIMA AREA WILL END BEFORE DAYBREAK AS THE
FRONT MOVES EAST. A SHORT WAVE ASSOCIATED WITH AN UPPER LOW WILL
LIFT NORTHEAST RAPIDLY TOWARD THE FORECAST AREA TODAY INTO TONIGHT.
OVERALL...NCEP MODELS JUST STARING TO PICK UP ON THIS SYSTEM...
ESPECIALLY THE NAM. FOR THIS PACKAGE...HAVE USED A BLEND OF MODELS
THAT APPEAR TO HAVE INITIALIZED AND VERIFIED THIS SYSTEM REASONABLY
WELL. LOW LEVEL MOISTURE FLUX IS EXTREMELY LIMITED AND ISENTROPIC
LIFT IS WEAK...SO GIVEN THE TIMING OF THIS SYSTEM...HAS INTRODUCED A
LOW CHANCE FOR SHOWERS LATE TONIGHT. OTHERWISE...THE HIGH
TEMPERATURE FORECAST FOR TODAY IS TRICKY GIVEN A FAIRLY SHARP
TEMPERATURE DROP BEHIND THE FRONT. EAST AREAS HIGHS WILL LIKELY BE
EARLY THIS MORNING AS COLD AIR ADVECTION OFFSETS DIURNAL WARMING.
&&
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 454 AM EDT WED OCT 16 2013
PRIMARY FOCUS ON TIMING OF SYSTEMS DY2 INTO THE WEEKEND. HIGHLY
ENERGIZED CONUS TROF PRESENT WITH SUBSTANTIVE TROP FOLD IN BASE THAT
ELONGATES THROUGH THE PLAINS INTO INTMTN WEST/CENTRAL ROCKIES. GOOD
AGREEMENT THAT THIS FEATURE WILL EJECT INTO IA AND CUTOFF MIDLVL
CIRCULATION ABOUT F30...THEN LIFT THROUGH THE UPPER GREAT LAKES ON
THURSDAY. STRONG MIDLVL HEIGHT FALLS OF 80-110M/12 HR ACROSS CENTRAL
ILLINOIS INTO HEART OF CWA 12-18 UTC THU IN TANDEM WITH STRONG 120KT
UPPER LEVEL JETSTREAK LIFTING ENEWD THROUGH THE OHIO VALLEY TO
PROVIDE DEEP LAYER ASCENT ACROSS OHIO VALLEY/SOUTHERN GREAT LAKES.
LOW LEVEL FGEN WAVE ALONG DECAYED/STALLED FRONTAL BOUNDARY ALONG
OHIO RIVER APPEARS STRONG ENOUGH TO WARRANT UPWARD NUDGE IN POPS.
SYSTEM LACK OF EXTREME BULK MOISTURE LESS CONVINCING GIVEN DECIDEDLY
COLD LOW LEVEL NATURE AND PINCHED DRY SLOT NOTED WITH SLIGHT
INCREASE IN AVAILABLE LOW-MID LVL MOISTURE LOCATED IN PRESENT
SECONDARY TROF AXIS OF PRESENT GREAT LAKES SYSTEM FROM CENTRAL
WI/NRN IA/NE. APPEARS BEST FOCUS FOR LIFT IN 12-18 UTC
TIMEFRAME...THOUGH HAVE REMAINED A BIT HESITANT ON STRICT TEMPORAL
RESOLUTION...SAVE FOR QUICK/ASSURED EXODUS BY EVENING AS JET
STREAK/FGEN COLLOCATION QUICKLY MOVES NEWD INTO LOWER GREAT LAKES/PA
RIDGE. QUICK LOW LEVEL THERMAL RECOVERY PER NAM/GFS AND WITH DECENT
AMOUNT OF SUN IN SRN CWA/DRY SLOT SHOULD PROVIDE STRONG DIURNAL PLUS
DAY FOR FRI. ALBEIT SHORT LIVED RECOVERY...AS PENT NORTHERN STREAM
ENERGY FINALLY ABLE TO UNLEASH FULL TILT BYND F72 INTO THE WEEKEND
WITH CROSS LATITUDINAL FLOW AMID STOIC 145W CENTERED RIDGELINE.
SURFACE REFLECTION FAIRLY STRONG FRIDAY NIGHT WITH 5H TROF AXIS INTO
WESTERN GREAT LAKES. THEREAFTER...COMPLEX FUJIWHARA INTERPLAY WITHIN
SEMI-PERMANENT CIRCUM POLAR-WESTERN HUDSON BAY VORTEX TO LIKELY
PRESENT TIMING/COVERAGE ISSUES OF EPISODIC SHRA INTO EARLY NEXT WEEK
AS GREAT LAKES/ERN CANADA TROF REMAINS DOMINANT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 141 PM EDT WED OCT 16 2013
MVFR CIGS WITHIN EXPANSIVE STRATOCU LYR ACRS THE NWRN HALF OF CWA
THIS AFTN WILL EXPAND SLOWLY EWD THROUGH TONIGHT. SCT -SHRA XPCD TO
DVLP AHD OF SW TROUGH LIFTING OUT OF THE FOUR CORNERS THU AM.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 5 AM EDT THURSDAY FOR LMZ043-046.
&&
$$
SYNOPSIS...KG
SHORT TERM...SKIPPER
LONG TERM...MURPHY
AVIATION...T
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