Area Forecast Discussion
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000
FXUS63 KLOT 260836
AFDLOT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
236 AM CST WED NOV 26 2014

.SHORT TERM...
236 AM CST

THROUGH THURSDAY...

BENIGN WEATHER EXPECT THROUGH THE SHORT TERM PERIOD AS CLIPPER
SYSTEM PASSES SOUTHWEST OF THE AREA TODAY. SNOW WITH THIS SYSTEM
WILL REMAIN WEST OF OUR CWA BUT EXTENSIVE CLOUD COVER...MOSTLY
MID-HIGH LEVEL...WILL KEEP CONDITIONS MOSTLY CLOUDY TODAY. HAVE
LOWERED TEMPS A BIT OVER THE MORE SOLID SNOW PACK REGION OVER ABOUT
THE NORTHWEST THIRD OF THE AREA. RE-ENFORCING SHOT OF ARCTIC AIR
SURGES INTO THE AREA LATER TONIGHT WHICH COULD ALLOW FOR SOME
FLURRIES TO BE SQUEEZED OUT OF THE STRATUS DECK AS THE TEMPS IN THE
CLOUDS COOL...BUT NOT LOOKING ANYTHING OF SIGNIFICANCE TO FALL.
THURSDAY LOOKS TO BE COLDEST DAY OF THE UPCOMING 7 DAYS WITH HIGHS
IN THE 20S...POSSIBLY NOT FAR INTO THE 20S OVER THE SNOW COVERED
AREAS.

IZZI

&&

.LONG TERM...
236 AM CST

THURSDAY NIGHT THROUGH WEDNESDAY...

SURFACE RIDGE MOVES EAST OF THE REGION THURSDAY NIGHT ALLOWING FOR
LIGHT SOUTHERLY WINDS TO DEVELOP AND BEGIN THE MODERATING TREND.
DESPITE THE DEVELOPING LIGHT SOUTH WINDS STILL EXPECT ANOTHER COLD
NIGHT...ESPECIALLY OVER SNOW PACK AREAS WHERE TEMPS COULD DIP TO
NEAR 10 OR EVEN INTO THE SINGLE DIGITS IN THE EVENING IF SKIES AREA
CLEAR. TEMPS WILL LIKELY LEVEL OFF AND POSSIBLY RISE A BIT LATE AS
CLOUDS INCREASE AGAIN. FOCUS FOR WAA PRECIP SHOULD REMAIN PRIMARILY
TO OUR NORTH WITH HIGHS FRIDAY MODERATING INTO THE 30S...AND
PROBABLY NEAR 40 IN THE SNOW-LESS PORTIONS OF THE AREA.

SOUTHERLY WINDS AND WARM AIR ADVECTION SHOULD PREVENT TEMPS FROM
FALLING OFF MUCH FRIDAY NIGHT FROM THE AFTERNOON HIGHS. THIS SHOULD
PROVIDE A NICE SPRING BOARD FOR TEMPS TO TAKE OFF ON SATURDAY.
GUIDANCE CONTINUES TO BE RATHER CONSERVATIVE WITH HIGHS...PROBABLY
TOO MUCH SO...ESPECIALLY FOR AREAS WITH LITTLE OR NO SNOW COVER. THE
850/925MB CLIMO WOULD SUPPORT HIGHS INTO THE 50S WHERE THERE IS NO
SNOW COVER AND HAVE BUMPED TEMPS UP INTO THIS RANGE. GIVEN THE
MODERATE SOUTH WINDS EVEN SNOW COVERED AREAS COULD BE NEAR 50. WHILE
I`VE BUMPED UP FORECAST TEMPS ABOVE GUIDANCE AM CONCERNED THESE
HIGHS ARE STILL POTENTIALLY TOO CONSERVATIVE BUT DIDNT WANT TO GET
TOO CARRIED AWAY.

MEDIUM RANGE MODEL HAVE SLOWED THE COLD FRONT DOWN THATS SCHEDULED
TO MOVE THROUGH SUNDAY. SLOWER FROPA MEANS WARMER TEMPS ON SUNDAY
AND IF COLD FRONT SLOWS ANY FURTHER IN LATER RUNS THEN SUNDAY COULD
END UP BEING JUST AS IF NOT A MORE MILD DAY THAN SUNDAY. FROPA LOOKS
TO BE MAINLY DRY AS DOES THE WEATHER THROUGH MUCH OF NEXT WEEK AT
THIS POINT...BUT BEHIND THE FRONT WE SHOULD RETURN TO BELOW AVERAGE
TEMPS...THOUGH NOT AS MUCH BELOW NORMAL AS WE HAVE GROWN ACCUSTOMED
TO.

IZZI

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 06Z...

* LOW END MVFR CEILINGS OVER THE NEXT 2-3 HOURS.

* LOW CHANCE FOR FOG EARLY THIS MORNING.

* EAST SOUTHEAST WIND TODAY...BUT BELOW 10 KT.

* FOR ORD...POSSIBLE RETURNING MVFR CEILINGS AND SNOW SHOWERS WITH
  FROPA LATE IN THE FORECAST PERIOD.

RODRIGUEZ

//DISCUSSION...UPDATED 06Z...

LOW STRATUS STILL LINGERING OVER MOST OF THE TERMINALS EARLY THIS
MORNING...EXCEPT RFD. DISTANCE SPEED TOOL SUGGESTS THIS STRATUS
WOULD EXIT TO THE EAST/NORTHEAST OVER THE NEXT 2-3 HOURS...WITH
MDW AND GYY OBSERVING MORE PREVAILING CONDITIONS. WITH THE
DEPARTURE OF THESE CLOUDS...SOME LOCATIONS HAVE OBSERVED FOG AND
WOULD THINK THIS WOULD BE A DEFINIITE POSSIBILITY OVER THE
TERMINALS ESPECIALLY FOR RFD/DPA. HAVE NOTED THIS IN THE TAFS FOR
THOSE LOCATIONS BUT WILL CONTINUE TO MONITOR THE OTHER SITES.
LIGHTER WINDS IN PLACE THIS MORNING WILL FURTHER DIMINISH BEFORE
BECOMING MORE SOUTHEAST LATER THIS MORNING...BUT REMAINING UNDER
10 KT LATER TODAY. VFR CONDITIONS WITH A LIGHT EASTERLY WIND WILL
BE OBSERVED FOR THE REMAINDER OF THE DAY INTO THIS EVENING.
APPROACHING SYSTEM OFF TO THE NORTHWEST WILL DROP WELL SOUTH OF
THE TERMINALS BUT AM MONITORING ANOTHER SYSTEM AND FROPA WHICH
COULD PROVIDE A PERIOD OF MVFR CEILINGS AS WELL AS SNOW SHOWERS
VERY LATE IN THE FORECAST PERIOD.

RODRIGUEZ

//ORD AND MDW CONFIDENCE...UPDATED 06Z...

* HIGH CONFIDENCE WITH LOW END MVFR CEILINGS AND DURATION.

* LOW CONFIDENCE WITH FOG EARLY THIS MORNING.

* HIGH CONFIDENCE WITH WIND SPEED/DIRECTION.

* LOW CONFIDENCE WITH RETURNING MVFR CEILINGS AND SNOW SHOWERS
  LATE.

RODRIGUEZ

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

THURSDAY...SLGT CHANCE OF MVFR LGT SNOW EARLY...OTHERWISE VFR.

FRIDAY...SLGT CHANCE OF LGT SNOW. MVFR POSSIBLE.

SATURDAY THROUGH MONDAY...PRIMARILY VFR...THOUGH A PERIOD OF MVFR
OR IFR CIGS  POSSIBLE SATAURDAY INTO EARLY SUNDAY.

RATZER

&&

.MARINE...
147 PM CST

A HIGH PRESSURE RIDGE CONTINUES TO PUSH EAST CAUSING WINDS TO
DIMINISH ACROSS THE REGION. MEANWHILE A LOW CURRENTLY OVER THE
DAKOTAS REACHES THE MID MISSISSIPPI VALLEY TOMORROW MORNING. LIGHT
WINDS BECOME EAST OVER THE SOUTHERN HALF OF THE LAKE AND VARIABLE
OVER THE NORTHERN HALF TOMORROW AFTERNOON.  THE LOW WEAKENS AS IT
PASSES OVER CENTRAL IL TOMORROW AND HIGH PRESSURE THEN BUILDS OVER
THE PLAINS TOMORROW NIGHT.  NORTH TO NORTHWEST WINDS INCREASE TO 30
KT THURSDAY AS THE PRESSURE GRADIENT INCREASES BETWEEN THE HIGH OVER
THE PLAINS AND LARGE LOW MOVING UP THE EAST COAST.  WINDS DIMINISH
AS THE HIGH MOVES OVER THE LAKE THURSDAY NIGHT.  WINDS THEN BECOME
SOUTH BEHIND THE HIGH FRIDAY.  GUIDANCE DIFFERS ON HOW QUICKLY THE
NEXT LOW MOVES OVER LAKE SUPERIOR...BUT THE PRESSURE GRADIENT
INCREASES AHEAD OF THE LOW RESULTING IN SOUTH WINDS AROUND 30 KT
LATE THIS WEEK. HAVE THE WINDS FORECASTED TO COME UP FRIDAY
AFTERNOON...BUT THEY COULD COME UP AS LATE AS SATURDAY MORNING. 20
KT WINDS PERSIST THROUGH THE WEEKEND WITH SOUTHWEST WINDS BECOMING
NORTH SUNDAY AFTERNOON.  ANOTHER HIGH PRESSURE SYSTEM MOVES OVER THE
LAKE EARLY NEXT WEEK WITH STRONG SOUTH WINDS BEHIND IT.

JEE

&&

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

$$

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