FXUS63 KLOT 262045
AFDLOT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
245 PM CST THU NOV 26 2009

.DISCUSSION...
245 PM CST

ONE LAST PATCHY AREA OF DRIZZLE IS MOVING EAST THROUGH NORTHWEST
INDIANA AS A SHORTWAVE TROF ROUNDS THE WESTERN EDGE OF THE CLOSED
UPPER LOW CENTERED OVER THE GREAT LAKES. A LOW STRATUS DECK WILL
REMAIN TRAPPED UNDER A STOUT INVERSION AROUND 3KFT PER ORD ACARS
SOUNDINGS AND WILL LIKELY PERSIST LONGER THAN GUIDANCE IS
SUGGESTING. WILL KEEP SKIES CLOUDY OVERNIGHT WITH GRADUAL CLEARING
TOWARD DAYBREAK WITH THE EXCEPTION OF SOME CIRRUS BLOWING IN ON
THE UPPER JET. TEMPERATURES WILL STRUGGLE TO CLIMB MUCH ON FRIDAY
GIVEN THE NORTHWESTERLY FLOW BUT SKIES SHOULD AT LEAST HAVE SOME
MORE SUN MAKING IT THROUGH THE CIRRUS.

SFC/UPPER LEVEL RIDGING WILL BE FORCING ITS WAY INTO THE REGION
FRIDAY NIGHT INTO SATURDAY WHICH WILL USHER IN SOME WARMER AIR
INTO THE GREAT LAKES. 850MB TEMPS WILL BE WARMING UP TO BETWEEN
+7C TO +10C WITH HIGH TEMPERATURES ON SATURDAY REACHING THE 50S.
SKIES ARE EXPECTED TO BE CLEAR AND SUNNY WITH SOUTH TO
SOUTHWESTERLY WINDS AHEAD OF THE NEXT WEAK SYSTEM MOVING INTO THE
REGION.

AS AN UPPER LEVEL TROF DIGS DOWN FROM CANADA INTO THE GREAT LAKES
ON SUNDAY...WE WILL GET OUR NEXT SHOT OF SOME LIGHT RAIN/SNOW AS A
SURFACE COLD FRONT MOVES THROUGH EARLY SUNDAY MORNING. PRECIP WILL
PERSIST NORTH OF THE FRONT ON SUNDAY INTO EARLY MONDAY WITH COLDER
AIR EVENTUALLY MOVING INTO THE REGION ON MONDAY.

THE FORECAST HAS BEEN BOUNCING AROUND FURTHER IN THE EXTENDED
PERIOD AS FOR WHETHER OR NOT A DEEPENING AREA OF LOW PRESSURE WILL
BE LIFTING UP INTO THE GREAT LAKES. THE CURRENT EXPECTATION IS
THAT HIGH PRESSURE WILL BE BUILDING IN SOUTH OF THE FORECAST WHICH
SHOULD KEEP OUR TEMPERATURES SEASONABLE FOR THIS TIME OF YEAR WITH
HIGHS IN THE LOW 40S AND LOWS JUST BELOW FREEZING. APPEARS AS
THOUGH THE LOW PRESSURE SYSTEM WILL BE PUT OFF UNTIL LATER IN THE
WEEK BUT CONFIDENCE IS RATHER LOW CONSIDERING HOW MUCH FLIP
FLOPPING THERE HAS BEEN AMONGST ALL OF THE EXTENDED GUIDANCE IN
THIS REGARD.

HALBACH

&&

.AVIATION...

1800 UTC TAFS...THE RADAR SHOWS LIGHT PRECIPITATION OVER NORTHEAST
ILLINOIS. WE EXPECT THIS TO CONTINUE THROUGH AT LEAST 20 UTC. WE
WILL ADD SOME LIGHT RAIN TO THE TERMINALS. THE TEMPERATURE WILL
BE WARM ENOUGH FOR RAIN ONLY. THE MVFR CEILING EXTENDS TO WESTERN
IOWA AND WESTERN MINNESOTA. THIS LOW CEILING OF 1500 TO 1900 FEET
CLOUDS WILL NOT MOVE EAST OF THE AIRPORTS IN NORTHEAST ILLINOIS
AND NORTHWEST INDIANA UNTIL THE UPPER AIR TROUGH MOVES EAST. WE
EXPECT THE TROUGH TO MOVE EAST AFTER 06 UTC TONIGHT. THE SKY WILL
BECOME SCATTERED WITH 25000 FT CLOUDS. THE WIND WILL REMAIN
NORTHWEST WITH GUSTS TO 25 TO 28 KNOTS. THE GUSTS WILL DECREASE
LATE TONIGHT AS THE SURFACE LOW OVER LAKE HURON MOVES EAST AND
WEAKENS. THE WIND WILL REMAIN NORTHWEST THROUGH THE NIGHT.

&&

.MARINE...
1251 PM CST

A LARGE AREA OF LOW PRESSURE EXTEND FROM WESTERN QUEBEC TO
NORTHERN ILLINOIS THIS MORNING. THIS AREA OF LOW PRESSURE WILL
DECREASE IN SIZE AND WEAKEN FRIDAY. AN INTENSE LOW WILL DEVELOP
OFF THE COAST OF VIRGINIA AND WILL MOVE INTO MAINE DURING THE DAY 
FRIDAY. AN AREA OF HIGH PRESSURE WILL EXTEND FROM LOUISIANA TO
ONTARIO BY FRIDAY EVENING. THE NORTHWEST WIND OF UP TO 30 KNOTS 
TODAY WILL DECREASE EARLY FRIDAY MORNING. BY FRIDAY NIGHT...THE 
WIND WILL BE SOUTH AROUND 5 TO 15 KNOTS..

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 4 AM 
     FRIDAY.

     SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 4 PM FRIDAY.

&&

$$