FXUS61 KCLE 151403
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
903 AM EST TUE DEC 15 2009
.SYNOPSIS...
A COLD FRONT OVER THE APPALACHIANS WILL MOVE OFF THE EAST COAST
TODAY. HIGH PRESSURE OVER THE PLAINS STATES WILL MOVE TO THE OHIO
VALLEY BY WEDNESDAY. A TROUGH OF LOW PRESSURE WILL LINGER OVER THE
EASTERN GREAT LAKES.
&&
.NEAR TERM /THROUGH TONIGHT/...
COLDER AIR FILTERING INTO THE AREA BUT NOT QUICK ENOUGH TO PUSH
TEMPS AT THE CLOUD LEVEL DOWN ENOUGH FOR ICE CRYSTALS TO FORM. THUS
WILL EXTEND THE MENTION OF SHOWERS AND DRIZZLE UNTIL NOON FOR EAST
HALF WITH JUST SPRINKLES OR FLURRIES FOR WEST HALF. ACCUMULATING
SNOW NOT EXPECTED TO DEVELOP UNTIL ABOUT MID AFTERNOON. TEMPS SHOULD
HOVER JUST ABOVE FREEZING UNTIL PRECIP HAS CHANGED TO MOSTLY
FLURRIES OR SHSN SO NOT LOOKING FOR ANY PROBLEMS DUE TO ANY FREEZING
DRIZZLE.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
MODELS HINT AT ANOTHER SHORT WAVE LATER WEDNESDAY. SHORT WAVE
COMBINED WITH THE ONSET OF WARM ADVECTION COULD TRIGGER ANOTHER
ROUND OF LAKE EFFECT/LAKE ENHANCED SNOW SHOWERS EXTREME NE OH/NW PA
ALTHOUGH IT DOES NOT LOOK IMPRESSIVE AT THIS TIME. CANNOT RULE OUT A
LOCAL INCH OR TWO OF ADDITIONAL SNOW MAINLY ACROSS INLAND NW PA
LATER WEDNESDAY AND WEDNESDAY NIGHT. SOME FLURRIES MAY DEVELOP
ELSEWHERE ACROSS NE OH/NW PA WITH SOME CLOUDS ACROSS NW OHIO. TEMPS
WILL FALL OFF IN AREAS WHERE THE WIND DROPS OFF. ELSEWHERE
TEMPERATURES MAY NOT DROP A LOT WEDNESDAY NIGHT. SURFACE HIGH BUILDS
IN ON THURSDAY BUT DIFFERENTIAL ADVECTION PROGGED TO CONTINUE ALOFT
SO THERE WILL LIKELY BE SOME ALTOCUMULUS AND PERHAPS SOME LINGERING
STRATOCUMULUS ESPECIALLY OVER THE SNOWBELT.
ALL MODELS DEVELOP AN INVERTED TROUGH BY THE END OF THE WEEK IN
RESPONSE TO A DEEPENING TROUGH ALOFT. NAM/WRF DEVELOPS A MORE WELL
DEFINED SURFACE LOW WHICH SEEMS OVERDONE. WITH THE TROUGH INITIALLY
DEEPENING WELL TO THE WEST...DO NOT WANT TO HURRY THE PRECIPITATION
AS THERE WILL LIKELY REMAIN SOME LOW DEWPOINT AIR TO OVERCOME AND A
DRY EAST-NORTHEAST FLOW. WILL MENTION A CHANCE OF LIGHT SNOW BY
FRIDAY NIGHT/SATURDAY. WITH THE FLOW FROM THE EAST... TEMPERATURES
WILL NOT HAVE A CHANCE TO WARM UP MUCH. GUIDANCE LOOKS PRETTY GOD
WITH MAX TEMPS IN THE UPPER 20S AND LOWER 30S.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
A TROUGH AXIS WILL EXTEND NORTHWEST ACROSS THE AREA ON SATURDAY WITH
SOME LIMITED ASSOCIATED MOISTURE. COLD AIR ADVECTION WILL ALSO TAKE
PLACE AS HIGH PRESSURE NUDGES SOUTH INTO THE REGION DURING THE DAY.
CURRENT FORECAST SUGGESTS A CHANCE OF SNOW FOR SATURDAY ALTHOUGH
GUIDANCE ONLY SHOWS A SLIGHT CHANCE. WILL CONTINUE WITH SLIGHT
CHANCE IN THE WEST HALF AND CHANCE IN THE EAST HALF.
SATURDAY NIGHT LOW PRESSURE SYSTEM MOVES UP THE ATLANTIC COAST AND
FEEDS MOISTURE BACK TO THE NORTHWEST INTO THE AREA. THIS MOISTURE
WILL CAUSE A THREAT FOR LIGHT SNOW SATURDAY NIGHT CONTINUING INTO
SUNDAY. COLD AIR ADVECTION AND NORTHWEST FLOW WILL CAUSE LAKE EFFECT
SNOW SHOWERS TO DEVELOP ACROSS THE REGION SUNDAY NIGHT AND CONTINUE
MONDAY AND TUESDAY.
TEMPERATURES DURING THE EXTENDED PERIODS WILL BE IN THE 20S TO LOWER
30S FOR HIGHS AND LOWS WILL BE IN THE TEENS.
EUROPEAN AND GFS MODELS HAVE SOME MAJOR DIFFERENCES TO OVERCOME TO
DETERMINE WHETHER CHRISTMAS WILL BE A WHITE ONE. EUROPEAN IS
POINTING TOWARD A COLD SNOWY CHRISTMAS WITH LAKE EFFECT WHILE GFS
SUGGESTS A WARM UP AND RAIN ON CHRISTMAS EVE WITH A STRONG COLD
FRONT MOVING THROUGH AREA DEVELOPING SNOW BY EVENING ON CHRISTMAS
EVE. IT IS A LONG WAYS OFF SO WE WILL KEEP AN EYE ON IT OVER THE
NEXT SEVERAL DAYS.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
COLD AIR ADVECTION BEGINNING TO TAKE PLACE IN THE WAKE OF THE
COLD FRONT THIS MORNING. CEILINGS RUNNING FAIRLY LOW AND THEY ARE
EXPECTED TO CHANGE LITTLE THROUGH THE DAY. SOME SNOW SHOWERS WILL
DEVELOP...MAINLY THIS AFTERNOON...ACROSS THE AREA BUT I DONT
EXPECT THEM TO REDUCE THE VISIBILITY MUCH BELOW 6 MILES. ERIE WILL
START TO SEE SOME LAKE EFFECT WITH A FEW STRONGER BANDS THAT WILL
TAKE THE VISIBILITY DOWN TO 2 MILES AT TIMES THIS AFTERNOON.
CEILINGS WILL IMPROVE IN THE WEST TONIGHT. WINDS THROUGH THE
PERIOD WILL BE INCREASING DURING THE DAY TO ABOUT 10 TO 20 KNOTS
BUT THEN DROP BACK OFF A BIT TONIGHT.
.OUTLOOK...NON VFR WEATHER TUESDAY EVENING THROUGH THURSDAY
MAINLY EASTERN PORTION AND EVERYWHERE IN THE FORECAST AREA FRIDAY
AND SATURDAY.
&&
.MARINE...
WILL KEEP SMALL CRAFT ADVISORIES FLYING AS WESTERLY FLOW CONTINUES
OVER THE LAKE AT ABOUT 15 TO 25 KNOTS. IT APPEARS THIS TREND WILL
LAST FOR SOME TIME UNTIL ABOUT WEDNESDAY NIGHT WHEN WINDS FINALLY
START TO DIMINISH. GENERALLY LIGHT AND VARIABLE FLOW SETS UP FOR
THURSDAY CONTINUING INTO FRIDAY. THEN...NORTHWEST FLOW DEVELOPS BY
FRIDAY NIGHT AT 10 TO 15 KNOTS. THIS SHOULD REMAIN BELOW SMALL
CRAFT CRITERIA INTO SATURDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 AM EST WEDNESDAY FOR
LEZ142>149.
&&
$$
SYNOPSIS...KOSARIK
NEAR TERM...KOSARIK/ADAMS
SHORT TERM...KOSARIK
LONG TERM...LOMBARDY
AVIATION...LOMBARDY
MARINE...LOMBARDY
