Area Forecast Discussion
Issued by NWS Chicago, IL

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000
FXUS63 KLOT 141858
AFDLOT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
158 PM CDT SUN SEP 14 2014

.DISCUSSION...
311 AM CDT

COOLER THAN AVERAGE AND EXCEPTIONALLY QUIET WEATHER ON TAP FOR THE
NEXT 7 DAYS.

SURFACE HIGH OVER THE REGION THIS MORNING WILL SHIFT EASTWARD WITH
WEAK WARM ADVECTION TODAY ALLOWING TEMPS TO REBOUND BACK INTO THE
60S AREA WIDE TODAY. NORTHWEST FLOW SHORTWAVE TROUGH WILL APPROACH
THE AREA LATE TONIGHT AND MOVE ACROSS THE REGION MONDAY BRINGING
FIRST AN INCREASE IN CLOUDINESS TONIGHT...WHICH SHOULD RESULT IN
TEMPS LEVELING OFF OR EVEN RISING A FEW DEGREES LATE
TONIGHT...FOLLOWED BY SOME SHOWERS MONDAY. STRONGEST FORCING PASSING
SOUTH SHOULD RESULT IN HIGHER COVERAGE OF PRECIP OVER SOUTHERN
PORTIONS OF THE CWA...THOUGH QPF LOOKS TO REMAIN ON THE LIGHT SIDE
EVEN THERE.

IN THE WAKE OF THE TROUGH GUIDANCE SUGGESTS A RAPID CLEARING OF
SKIES MONDAY NIGHT...WHICH IF IT VERIFIES COULD ALLOW FOR ANOTHER
UNSEASONABLY COLD EARLY FALL NIGHT WITH SOME LOW DIPPING INTO THE
30S AGAIN IN THE COLDEST LOCATIONS. TUESDAY WILL REMAIN MUCH BELOW
AVERAGE...THOUGH LOOKS TO BE THE FIRST OF SEVERAL CONSECUTIVE DAYS
OF SUNNY AND DRY CONDITIONS. SFC HIGH NEAR BY COULD ALLOW FOR GOOD
RADIATIONAL COOLING SET-UP TUES NIGHT WITH ANOTHER NIGHT WITH THE
POTENTIAL FOR INLAND 30S. SLOW MODERATING TREND LOOKS TO BEGIN MID
WEEK AND CONTINUE INTO NEXT WEEKEND WHEN HIGHS COULD CLIMB BACK
ABOVE AVERAGE. DESPITE THE RECENT COLD SNAP...IT IS LIKELY WE WILL
STILL SEE SOME WARM DAYS BEFORE THE DECENT INTO WINTER AS OUR
AVERAGE LAST 80 DEGREE DAY ISNT UNTIL THE FIRST WEEK OF OCTOBER.

IZZI

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 18Z...

* NONE IN THE NEAR TERM.

* VFR CEILINGS AND RAIN ARRIVING MID MORNING ON
  MONDAY...CONTINUING THROUGH MID/LATE AFTERNOON.

* MVFR CEILINGS BY MIDDAY MONDAY...POSSIBLY IFR FOR A TIME.

* SOUTHWEST WINDS BECOMING WEST AND THEN NORTHWEST MONDAY
  MORNING...BECOMING MORE NORTHERLY LATE IN THE FORECAST PERIOD.

RODRIGUEZ

//DISCUSSION...UPDATED 18Z...

HIGH PRESSURE REMAINING IN PLACE EARLY THIS AFTERNOON ALLOWING FOR
QUIET CONDITIONS ACROSS THE TERMINALS...WHILE A LIGHT SOUTHWEST
WIND PERSISTS. VFR CONDITIONS WILL CONTINUE THIS AFTERNOON INTO
TONIGHT...WHILE MID/HIGH LEVEL CLOUD COVER SLOWLY INCREASE
TONIGHT. WINDS VARYING FROM WEST SOUTHWEST TO SOUTH SOUTHWEST WILL
LIKELY CONTINUE THIS AFTERNOON...BUT WITH THE PREVAILING DIRECTION
STAYING IN THIS SOUTHWEST DIRECTION. CURRENT SURFACE TROUGH TO THE
WEST WILL APPROACH THE TERMINALS ON MONDAY AND AS THIS
OCCURS...EXPECT RAIN TO OVERSPREAD THE TERMINALS THROUGH MONDAY
MORNING AND LIKELY INCREASE IN INTENSITY THROUGH MID DAY. DONT
ANTICIPATE VIS TO FALL TOO LOW IN THIS LIGHT RAIN...FALLING TO AT
MOST 3-5SM AT TIMES. PRECIP SHIELD WILL LIKELY BE FAIRLY
PROGRESSIVE EXITING THE TERMINALS BY MID/LATE AFTERNOON.
CONFIDENCE IS HIGH WITH CEILINGS LOWERING TO MVFR DURING THIS TIME
BUT LOW WITH THE POSSIBILITY OF IFR CEILINGS. IFR CEILINGS WILL
LIKELY BE PRESENT AROUND THE TERMINALS BUT LIKELY BE
PATCHY...UNDER THE BETTER PRECIP DEVELOPMENT.

RODRIGUEZ

//ORD AND MDW CONFIDENCE...UPDATED 18Z...

* HIGH CONFIDENCE WITH VFR CONDITIONS IN THE NEAR TERM.

* HIGH CONFIDENCE OF RAIN...MEDIUM HIGH CONFIDENCE OF TIMING AND
  DURATION.

* MEDIUM HIGH CONFIDENCE OF MVFR CEILINGS AND TIMING...LOW
  CONFIDENCE OF IFR.

* MEDIUM HIGH CONFIDENCE WITH WIND SPEED/DIRECTION.

RODRIGUEZ

//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...

MONDAY...CHANCE OF SHOWERS IN THE AFTERNOON/EVENING WITH MVFR PSBL.
TUESDAY THROUGH FRIDAY...PRIMARILY VFR.
SATURDAY...CHANCE OF THUNDERSTORMS.

BMD

&&

.MARINE...
144 PM CDT

HIGH PRESSURE CENTERED OVER THE OHIO VALLEY WILL CONTINUE TO
SLOWLY LIFT NORTHEAST...BECOMING CENTERED OVER NEW ENGLAND MONDAY
MORNING. ALONG THE WESTERN END OF THIS HIGH PRESSURE CENTER IS A
TIGHTER GRADIENT...WHICH HAS BECOME EVIDENT ALONG THE NORTHERN
PORTIONS OF LAKE MICHIGAN WITH WINDS GUSTING AT TIMES TO 30KT FROM
THE SOUTHWEST. A FRONTAL BOUNDARY WILL SWEEP ACROSS LAKE MICHIGAN ON
MONDAY TURNING WINDS WEST/NORTHWEST. THEN ANOTHER RIDGE OF HIGH
PRESSURE WILL BRING ANOTHER PERIOD OF LIGHTER WINDS TO THE LAKE
MONDAY NGT THRU TUE.

HIGH PRESSURE WILL THEN REMAIN IN PLACE THROUGH EARLY
THURSDAY...THEN LIFT NORTHEAST WITH FLOW TURNING SOUTHERLY AND A
TIGHTENING GRADIENT THURSDAY NGT THROUGH FRIDAY. AT THIS TIME IT
IS POSSIBLE WIND COULD GUST TO 30KT FRIDAY NIGHT INTO
SATURDAY...MAINLY FOR THE NORTHERN HALF OF THE LAKE.

BEACHLER

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&

$$

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