FXUS61 KCLE 120818
AFDCLE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
318 AM EST SAT DEC 12 2009

.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST OFF THE CAROLINA COAST TODAY. A COLD
FRONT WILL APPROACH THE AREA TONIGHT AS A WAVE OF LOW PRESSURE
MOVES NORTHEAST. THE LOW WILL MOVE INTO THE CENTRAL GREAT LAKES BY
TONIGHT. THE COLD FRONT WILL MOVE EAST ACROSS THE AREA SUNDAY
NIGHT FOLLOWED BY A WEAK AREA OF HIGH PRESSURE MONDAY MORNING.
&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WEATHER SHOULD BE RATHER QUIET FOR TODAY AS HIGH PRESSURE MOVES EAST 
OF THE AREA AND SOUTHERLY WARM AIR ADVECTION DEVELOPS. LAKE EFFECT 
SNOW SHOWERS HAVE FINALLY COME TO AN END AND MOST AREAS WILL SEE 
SOME SUNSHINE THIS MORNING.  A LINGERING BAND OF CLOUDS CONTINUES TO 
AFFECT ERIE COUNTY OF PENNSYLVANIA BUT THIS TOO WILL END AS FLOW 
SHIFTS FETCH AWAY FROM THE LAKE. 

I EXPECT TO SEE INCREASING CLOUDS THROUGHOUT THE DAY IN ADVANCE OF 
THE NEXT SYSTEM FORECAST TO MOVE INTO THE AREA.  FORECAST AREA 
SHOULD REMAIN DRY THROUGH THE DAY AND EXPECTING ANY PRECIPITATION TO 
HOLD OFF UNTIL TONIGHT.

TEMPERATURES WILL BE WARMER TODAY AS WARM AIR ADVECTION STARTS TO 
OCCUR OVER THE AREA.  I ANTICIPATE SEEING TEMPERATURES CLIMB INTO 
THE MIDDLE 30S MOST AREAS EXCEPT NEAR 40 IN THE EXTREME SOUTH AND 
LOWER 30S SOUTH OF INTERSTATE 90 IN ERIE AND CRAWFORD COUNTIES OF 
PENNSYLVANIA. 

&&

.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
NAM MODEL IS A BIT SLOWER BY A COUPLE HOURS IN BRINGING THE 
PRECIPITATION INTO THE FORECAST AREA DURING THE NIGHT TIME HOURS.  
MODEL SOUNDINGS SUPPORT A LOT OF WARM AIR ADVECTION ABOVE THE 
SURFACE WHILE SURFACE TEMPERATURES HOVER AROUND THE FREEZING MARK. I 
THINK WITH CLOUD COVER EXPECTED IN PLACE...WE SHOULD SEE 
TEMPERATURES WARMING DURING THE NIGHT...EXCEPT UP IN THE EXTREME 
NORTHEAST. PRECIPITATION COULD START OUT IN THE FORM OF FREEZING 
RAIN AS PRECIPITATION AREA MOVES EAST BUT IT SHOULD ONLY LAST AN 
HOUR OR TWO.  WARM AIR WILL CHANGE THE PRECIPITATION OVER TO ALL 
RAIN AS HEAVIER RAIN ACTIVITY MOVES INTO THE REGION ON SUNDAY.

PRECIPITATION MOVES EAST ACROSS THE AREA ON SUNDAY AND EXITS TO THE 
EAST SUNDAY EVENING.  DRY AIR MASS PUSHES INTO THE AREA SUNDAY NIGHT 
AND ALL AREAS SHOULD BE DRY AFTER MIDNIGHT. 

NEXT LOW PRESSURE SYSTEM HEADS OUR WAY FROM THE WEST WITH VIGOROUS 
UPPER LEVEL SHORTWAVE AND ASSOCIATED MOISTURE. TEMPERATURES SHOULD 
DROP TO JUST BELOW FREEZING OVER THE WEST ALONG WITH COLD AIR 
ADVECTION ALLOWING PRECIPITATION TO BECOME MIXED WITH AND THEN 
CHANGE OVER TO ALL SNOW MOST AREAS BY SUNRISE.

TUESDAY WILL SEE A TRANSITION INTO LAKE EFFECT SNOW AS HIGH PRESSURE 
BUILDS SLOWLY EAST. LAKE EFFECT AND COLD AIR ADVECTION WILL CONTINUE 
INTO TUESDAY NIGHT WITH ANOTHER POTENTIAL POSSIBLY FOR SIGNIFICANT 
ACCUMULATIONS IN THE SNOW BELT AREAS. ALTHOUGH...TRAJECTORY MAY BE 
MORE NORTHWEST FORCING LAKE SNOWS INTO THE SECONDARY SNOW BELT 
AREAS. WILL HAVE TO WATCH AND SEE HOW THIS DEVELOPS.

&&

.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
THE LONG TERM BEGINS WEDNESDAY MORNING WITH HIGH PRESSURE BUILDING 
INTO THE AREA FROM THE WEST.  GFS SHOWS COLD BUT DRY AIR MOVING IN 
FROM THE WEST.  ONLY PROBLEM WILL BE THE POSSIBILITY OF A CONTINUING 
LAKE EFFECT EVENT WITH NORTHWEST FLOW AND 850MB TEMPS AROUND -14C. 
CURRENT FORECAST LOOKS GOOD WITH LIKELY POPS FOR SNOW SHOWERS IN THE 
SNOW BELT.  WILL ALSO HANG ONTO CHANCES WEDNESDAY NIGHT AND THURSDAY 
WITH A LOWERING POP TREND. FAST MOVING CLIPPER SHOWN ON THE GFS FOR 
FRIDAY SO WILL BRING BACK CHC POPS FOR SNOW. TEMPS TOUCHY HOWEVER 
AND WILL NEED TO WATCH AS A BIT MORE WARMING WOULD TURN FRIDAY 
PRECIP TO RAIN OR A MIX OF RAIN/SNOW.

&&

.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
SCATTERED LAKE EFFECT SNOW SHOWERS LINGER NEAR KERI AND LOCALLY
NON VFR WEATHER COULD OCCUR IN THESE SNOW SHOWERS. THE SNOW SHOULD
SHOULD BE GONE BY AROUND 12Z WITH SKIES CLEARING THERE LATER IN
THE MORNING. ELSEWHERE MOSTLY CLEAR SKIES EXPECTED THROUGH 00Z
SUNDAY...THEN JUST AN INCREASE IN MID AND HIGH CLOUDS ACROSS THE
AREA THROUGH 06Z. MIXED PRECIP MAY START TO SPREAD INTO THE AREA
FROM THE SOUTH BETWEEN 06Z-12Z SUNDAY

.OUTLOOK...NON VFR DEVELOPING SUNDAY AND LIKELY CONTINUING INTO
TUESDAY. NON VFR MAINLY NE WEDNESDAY.

&&

.MARINE...
WILL CONTINUE WITH THE SMALL CRAFT ADVISORY ON THE EAST HALF.  WINDS 
HAVE DROPPED OFF ON THE WEST HALF BUT CONTINUE AT 20 TO 25 KNOTS 
GUSTING TO AROUND 30KTS.  WINDS WILL BACK DURING THE MORNING HOURS 
AND THEN TURN OUT OF THE SOUTH FOR THE AFTERNOON ALLOWING WAVES TO 
DIMINISH. HIGH PRESSURE OVER THE VIRGINIAS WILL DRIFT TO THE MID 
ATLANTIC COAST TODAY. SUNDAY THE HIGH WILL BE FURTHER EAST AND A 
COLD FRONT WILL DROP ACROSS THE WESTERN LAKES.  THE SURFACE LOW WILL 
REMAIN WELL NORTH IN CANADA AND THE WEAKENING BOUNDARY WILL DROP 
ACROSS THE LAKE SUNDAY NIGHT AND STALL ACROSS CENTRAL OHIO.  THE 
FRONT WILL MOVE BACK NORTH OF THE LAKE AS A WARM FRONT MONDAY 
EVENING.  THE LOW WILL MOVE ACROSS THE CENTRAL LAKES MONDAY NIGHT 
AND REACH NEAR TORONTO ON TUESDAY MORNING. AHEAD OF THE LOW...WARM 
ADVECTION WILL TAKE PLACE LIKELY LIMITING THE MOMENTUM TRANSFER TO 
THE SURFACE HOWEVER NEUTRAL TO COLD ADVECTION BEGINS TUESDAY WHICH 
WILL ALLOW WINDS TO INCREASE DURING THE DAY AND INTO TUESDAY NIGHT. 
PREVIOUS MODEL RUN SUGGESTED POSSIBLE GALES HOWEVER THE CURRENT RUN 
HAS BACKED OFF JUST A BIT AND WILL HAVE WINDS GO TO 30 KNOTS TUESDAY 
NIGHT. GRADIENT RELAXES WEDNESDAY AS HIGH PRESSURE BEGINS TO BUILD 
IN. 

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR 
     LEZ145>149.

&&

$$
SYNOPSIS...LOMBARDY
NEAR TERM...LOMBARDY
SHORT TERM...LOMBARDY
LONG TERM...TK
AVIATION...RANDEL
MARINE...TK