637
FXUS61 KCLE 021147
AFDCLE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CLEVELAND OH
647 AM EST MON DEC 2 2024
SYNOPSIS
A SURFACE TROUGH WILL CONTINUE TO LINGER ACROSS THE AREA INTO
TUESDAY BEFORE A BRIEF HIGH PRESSURE BUILDS EAST TUESDAY AFTERNOON.
ANOTHER STRONG LOW PRESSURE SYSTEM WILL MOVE EAST ACROSS THE REGION
WEDNESDAY THROUGH THURSDAY BEFORE HIGH PRESSURE RETURNS ON
FRIDAY.
NEAR TERM /THROUGH TUESDAY/
630 AM UPDATE...
LAKE EFFECT SNOW SHOWERS CONTINUE TO STREAM ACROSS THE PRIMARY
SNOWBELT THIS MORNING WITH GENERAL RATES OF LESS THAN 1"/HR
BEING OBSERVED. UPTICKS IN THIS RATE IS POSSIBLE THROUGHOUT
TODAY IN THE HEAVIEST BANDS THAT DEVELOP. WITH THIS UPDATE,
SLIGHT ADJUSTMENTS WERE MADE TO TEMPERATURES AS THEY STAYED A
BIT WARMER THAN PREVIOUSLY FORECAST, BUT THE REMAINDER OF THE
FORECAST REMAINS ON TRACK.
PREVIOUS DISCUSSION...
THE LAKE EFFECT MACHINE CONTINUES TO PRODUCE SNOW SQUALLS
ACROSS THE SNOWBELT REGION, ALTHOUGH THE MESOSCALE FACTORS ARE
SLOWLY BEGINNING TO WEAKEN. THE BIG SHIFT WITH LAKE EFFECT TODAY
WILL BE DUE TO A PREDOMINANTLY NORTHWEST STEERING FLOW
RESULTING IN MORE OF A MULTI- BAND SYSTEM PUSHING INLAND AS FAR
EAST AS CUYAHOGA COUNTY AND REACHING FURTHER SOUTH INTO
GEAUGA/TRUMBULL COUNTIES ALONG THE HIGHER TERRAIN. THIS SHIFT IN
DIRECTION WILL DIMINISH THE FETCH ACROSS LAKE ERIE, WITH THE
EXCEPTION ACROSS NWPA WHERE A CONNECTION TO LAKE HURON HAS
DEVELOPED. DEFINED BANDS WILL BE HARD TO DETERMINE AHEAD OF TIME
AS INCREASED SHEAR IS RESULTING IN THE SNOW SHOWERS FANNING OUT
A BIT AND MAKING THE EXACT LOCATION A BIT MORE DIFFICULT
COMPARED TO PREVIOUS DAYS. THERE REMAINS A CONVERGENT BOUNDARY
ACROSS THE SNOWBELT REGION WITH MODEL SOUNDINGS SUGGESTING AN
INCREASING EQL TO 15+KFT TODAY. THIS COUPLED WITH PERSISTENT
850MB TEMPERATURES OF -10 TO -12C AND GOOD OMEGA LIFT WITHIN THE
DGZ WILL MAINTAIN AN ENVIRONMENT CONDUCIVE TO SNOWBANDS
CONTINUING TO FORM FOR MUCH OF THIS PERIOD. IF THERE IS A SILVER
LINING IN THESE CONDITIONS IT IS THAT THE OVERALL SNOWFALL
RATES SHOULD BE LESS TODAY WITH THE STRONGEST RATES NEAR 1"/HR.
ONE OF THE BIGGEST CHANGES WITH THE UPDATE THIS MORNING IS THAT SOME
HI-RES MODELS TRY TO PUSH A DRIER AIRMASS FURTHER EAST TODAY,
ULTIMATELY LOWERING QPF TOTALS. THIS IS RELATIVE AS AREAS ACROSS THE
SNOWBELT ARE STILL MAINTAINING TOTAL QPF VALUES OF 0.25-0.5". GIVEN
EXPECTED SNOW RATIOS AVERAGING 15:1, THIS WILL RESULT IN ADDITIONAL
SNOWFALL TOTALS OF 4-10" ACROSS PORTIONS OF THE OHIO SNOWBELT, WITH
AN ADDITIONAL 10-20" POSSIBLE ACROSS NWPA. AREAS INLAND, INCLUDING
TRUMBULL AND PORTAGE COUNTIES, COULD SEE 1-3" OF SNOW THROUGH THIS
PERIOD.
THROUGHOUT THIS ENTIRE PERIOD, TEMPERATURES WILL BE SLIGHTLY WARMER
THAN THE LAST COUPLE DAYS WITH HIGHS CLIMBING TO NEAR FREEZING BOTH
DAYS. OVERNIGHT LOWS WILL REMAIN COLD, DROPPING INTO THE LOW TO MID
20S WITH APPARENT TEMPERATURES FALLING INTO THE LOW TEENS INLAND
FROM THE LAKE.
WRAPPING THINGS UP, IT IS IMPORTANT TO NOTE THAT EVEN WITH A
SLIGHTLY MORE 'OPTIMISTIC' FORECAST THIS MORNING, THE WIDESPREAD
IMPACTS FROM THIS SYSTEM AS A WHOLE WILL CONTINUE TO BE FELT AND
PEOPLE SHOULD ADHERE TO ALL GUIDANCE FROM LOCAL OFFICIALS. ACROSS
AREAS OF THE SNOWBELT THAT CONTINUE TO BE IMPACTED, INCLUDING AREAS
ALONG AND NORTH OF I-90, PEOPLE SHOULD NOT TRAVEL UNLESS ABSOLUTELY
NECESSARY AND IF REQUIRED TO VENTURE OUT BE SURE TO HAVE A
PREPAREDNESS CAR KIT WITH YOU. CLEAN-UP FROM THIS EVENT WILL TAKE
DAYS SO LINGERING IMPACTS WILL BE FELT EVEN IF IT IS NOT ACTIVELY
SNOWING.
SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/
THE SHORT TERM FORECAST PERIOD REMAINS VERY ACTIVE FOR THE FORECAST
AREA WITH A TRANSITION FROM JUST LAKE EFFECT SNOW TO A WEATHER
SYSTEM THAT COULD HAVE IMPACTS ACROSS THE ENTIRE FORECAST AREA. FOR
TUESDAY NIGHT, HIGH PRESSURE WILL BE INCHING UP THE OHIO AND
TENNESSEE RIVER VALLEYS AS IT ADVANCES SOUTHEAST. THE MEAN LOW LEVEL
RIDGE AXIS SHOULD BE OVER THE MIDDLE OF THE FORECAST AREA AT THE
START OF THE SHORT TERM FORECAST PERIOD AND SHOULD ALLOW FOR BACKING
AND WARMING FLOW ACROSS THE REGION. THIS SHOULD START TO WIND DOWN
THE LAKE EFFECT EVENT AND PUSH ANY REMAINING BANDS NORTH OVER LAKE
ERIE AND THROUGH NEW YORK AND EVENTUALLY TO CANADA. THERE COULD BE
AN INCH OF SNOW OR SO OUT OF SCATTERED LAKE EFFECT SHOWERS IN ERIE
COUNTY PA, BUT NOTHING COMPARED TO THE LAST SEVERAL DAYS.
FOR WEDNESDAY, A STRONG LOW PRESSURE SYSTEM WILL ARRIVE NEAR LAKE
SUPERIOR. THE LOCAL FORECAST AREA WILL REMAIN BETWEEN THIS STRONG
LOW AND A DEPARTING HIGH PRESSURE SYSTEM TO THE SOUTHEAST.
ACCORDINGLY, BETWEEN THESE TWO SYSTEMS A STRONG LOW LEVEL JET OF 55
KT AT 850 MB WILL BE PRESENT ACROSS THE REGION AND SHOULD MIX DOWN
TO THE SURFACE IN SOME CAPACITY WEDNESDAY AFTERNOON AND BEYOND. WIND
GUSTS OF 40 MPH OR GREATER ARE POSSIBLE. THE STRONGEST WINDS WILL BE
WITH THE ASSOCIATED COLD FRONT ON WEDNESDAY EVENING AS THIS FEATURE
WILL BRING SNOW AND PERHAPS SOME BRIEF MIX TO RAIN ACROSS THE
REGION. A WIND ADVISORY MAY BE NEEDED FOR THE MIDDLE OF THE WEEK TO
ACCOUNT FOR THE ELEVATED WINDS.
FOR WEDNESDAY NIGHT AND BEYOND, THE COLD FRONT WILL PASS TO THE EAST
AND ALLOW AN OPPORTUNITY FOR THE LAKE EFFECT SNOW MACHINE TO GET
GOING AGAIN. FOR THIS EVENT, THE AIR ALOFT WILL ACTUALLY BE COLDER
THAN IT WAS FOR THE CURRENT EVENT WITH -13 TO -14 C AT 850 MB AND A
FRIGID -23 TO -25C AT 700 MB, WHICH WOULD SUPPORT AMPLE LAKE INDUCED
INSTABILITY WITH LAKE SURFACE TEMPERATURES LIKELY STILL RESIDING IN
THE 5-7C RANGE. UNLIKE THE CURRENT LAKE EFFECT EVENT, THERE WILL BE
SOME FACTORS GOING AGAINST PROLIFIC LAKE EFFECT SNOW AMOUNTS. THERE
ARE MUCH STRONGER WINDS IN PLACE WITH THE MEAN FLOW IN THE BOUNDARY
LAYER AT ABOUT 30 KTS, IF NOT SLIGHTLY HIGHER. THIS WILL REDUCE
RESIDENCE TIME FOR PARCELS OVER THE LAKE, ESPECIALLY IN THE SHORTER
NORTHWEST FETCH ACROSS LAKE ERIE. THE OTHER LIMITING FACTOR WILL BE
MOISTURE, THERE SHOULD BE SUFFICIENT MOISTURE FOR SNOW DEVELOPMENT
DURING THE ONSET OF THE EVENT ON WEDNESDAY NIGHT INTO THURSDAY.
HOWEVER, DRIER, CONTINENTAL AIR WILL BE WRAPPING IN BEHIND THE
LARGER LOW PRESSURE SYSTEM AND PRECIPITATION EFFICIENCY MAY BE
HINDERED QUICKLY, LEAVING SNOW BANDS LIMITED TO WHERE THERE WILL BE
HELP FROM UPSTREAM LAKE CONNECTIONS. OVERALL, EXPECT MOST OF THE
SNOW BELT TO AT LEAST SEE SOME ACCUMULATING SNOW AMOUNTS WEDNESDAY
NIGHT THROUGH THURSDAY NIGHT, BUT DETAILS WILL NEED TO BE REFINED
BEFORE THINKING ABOUT HEADLINE NEEDS. THE SECONDARY SHOULD AT LEAST
GET SOMEWHAT MORE INVOLVED WITH SNOW WITH THE STRONG NORTHWEST FLOW.
TEMPERATURES THROUGH THE PERIOD REMAIN BELOW NORMAL WITH HIGHS IN
THE 20S AND PERHAPS SOME UPPER 20S ON THURSDAY.
LONG TERM /FRIDAY THROUGH SUNDAY/
WHILE IT IS UNLIKELY TO SAY THAT THE LONG TERM FORECAST PERIOD WILL
BE QUIET, IT APPEARS THAT THERE WILL BE AT LEAST SOME REPRIEVE TO
ACTIVE WEATHER ACROSS THE LOCAL AREA FOR FRIDAY AND PERHAPS INTO THE
WEEKEND. HIGH PRESSURE WILL BUILD FROM THE WEST FOR FRIDAY. THIS
SHOULD BACK FLOW ACROSS THE LAKE AND PUSH ANY LAKE EFFECT SNOW
NORTHEAST AND OUT OF THE AREA. FOR SATURDAY, A CLIPPER SYSTEM WILL
TARGET THE GREAT LAKES REGION. HOWEVER, THIS SYSTEM IS TRENDING BOTH
NORTH AND WEAKER AND IT IS UNCERTAIN HOW MUCH OF AN IMPACT WITH
PRECIPITATION AND TEMPERATURES THAT IT WILL HAVE FOR THE LOCAL AREA.
WILL HAVE SOME LOWER END POPS FOR THE BULK OF THE AREA, BUT CAN SEE
THIS GETTING LOWERED WITH TIME. FOR SUNDAY, A RIDGE WILL BUILD FROM
THE SOUTHWEST AND SHOULD AT LEAST ALLOW FOR A WINDOW OF DRY WEATHER
WITH MODERATING TEMPERATURES BEFORE ANOTHER LOW PRESSURE SYSTEM
ENTERS NEXT WEEK. TEMPERATURES ON SUNDAY COULD BE NEAR NORMAL FOR
THE FIRST TIME IN A WEEK AND A HALF.
AVIATION /12Z MONDAY THROUGH FRIDAY/
LAKE EFFECT CLOUDS COMING OFF OF LAKE MICHIGAN HAVE DETERIORATED AND
ALLOWED FOR PREDOMINATELY VFR CONDITIONS TO EXTEND ACROSS THE
AREA. THE EXCEPTION TO THIS IS FOR TERMINALS IN NE OH AND NW PA
WHERE ONGOING LAKE EFFECT SNOW SHOWERS OFF OF LAKE ERIE CONTINUE
TO BOUNCE CONDITIONS BETWEEN VFR AND IFR. THIS WILL LIKELY BE
THE CASE FOR KYNG AND KERI THROUGHOUT THIS PERIOD AS THESE SNOW
SHOWERS ARE EXPECTED TO PERSIST AND VISIBILITIES IN THE HEAVIEST
BAND MAY BRIEFLY DROP TO LESS THAN 2SM AT TIMES. EXACT TIMING
OF THESE BANDS REMAINS UNCERTAIN GIVEN THE MORE SCATTERED NATURE
OF THESE SNOW SHOWERS TODAY. BEST CHANCE WILL BE THROUGH 00Z
TONIGHT FOR KYNG WITH A LONGER POTENTIAL LINGERING IN KERI
ESPECIALLY AS A LAKE HURON CONNECTION BECOMES ESTABLISHED.
IN ADDITION TO IMPACTS AT THOSE TERMINALS, KCLE HAS THE
POTENTIAL TO ALSO BE IMPACTED BY NON-VFR CONDITIONS TODAY AS THE
AFOREMENTIONED LAKE EFFECT BANDS SAG SOUTH. THERE IS A HIGH
AMOUNT OF UNCERTAINTY WITH HOW FAR WEST THESE BANDS WILL EXTEND
AND IF THERE WILL BE NOTABLE IMPACTS TO KCLE SO OPTED FOR A MORE
OPTIMISTIC FORECAST AT THIS POINT ONLY DROPPING VISIBLIITIES TO
4SM IN THE SNOW SHOWERS. WILL HAVE TO CONTINUE TO MONITOR
FORECAST TRENDS FOR MORE SIGNIFICANT IMPACT POTENTIAL AT THIS
TERMINAL.
PREDOMINATELY WEST WINDS OF 5-10 KNOTS WILL PERSIST THROUGH THIS
PERIOD, SLOWLY SHIFTING TO NORTHWEST NEAR THE END. KERI MAY BE
THE OUTLIER WITH SUSTAINED WINDS A TAD STRONGER IN THE 10-15
KNOT RANGE GIVEN THE STRONG FLOW OFF OF THE LAKE.
OUTLOOK...NON-VFR LIKELY IN LAKE-EFFECT SNOW BANDS THROUGH
TUESDAY. THE HEAVIEST AND MOST-PERSISTENT LAKE-EFFECT SNOW IN
OUR REGION IS EXPECTED TO IMPACT THE PRIMARY SNOWBELT IN FAR
NORTHEAST OHIO AND NORTHWEST PENNSYLVANIA.
MARINE
TROUGH OVER THE LAKE WILL CONTINUE TODAY AND WILL ALLOW FOR THE 15
TO 20 KT WESTERLY FLOW TO REMAIN IN PLACE AND WAVES OVER 4 FT FOR
THE CENTRAL AND EASTERN BASINS. FOR TUESDAY, HIGH PRESSURE WILL
BUILD SOUTHWEST OF THE LAKE AND INCREASE THE PRESSURE GRADIENT
ACROSS THE REGION AS THE MAIN TROUGH MOVES OUT. THEREFORE, WEST
WINDS 15 TO 20 KT WILL CONTINUE WITH WAVES OVER 4 FT AND WILL
CONTINUE THE SMALL CRAFT ADVISORY THROUGH 7 AM WEDNESDAY. FOR
WEDNESDAY AND THURSDAY, A STRONG LOW PRESSURE SYSTEM AND ASSOCIATED
COLD FRONT WILL CROSS THE GREAT LAKES REGION. SOUTHWEST WINDS WILL
INCREASE GREATLY ON WEDNESDAY AHEAD OF THE SYSTEM WITH THE POTENTIAL
FOR GALE FORCE WINDS. THE COLD FRONT WILL MOVE THROUGH ON WEDNESDAY
NIGHT AND WEST TO NORTHWEST FLOW WILL BE STRONG WITH GALE FORCE
WINDS POSSIBLE WEDNESDAY NIGHT INTO THURSDAY. WILL BEGIN MENTIONING
IN THE HAZARDOUS WEATHER OUTLOOK, BUT A GALE WATCH MAY BE NEEDED
WITHIN THE NEXT ONE OR TWO FORECAST CYCLES. HIGH PRESSURE WILL
RETURN SOUTHWEST OF THE REGION FOR FRIDAY AND BOTH REDUCE AND BACK
FLOW ACROSS THE LAKE AND THERE COULD BE A BRIEF WINDOW WITHOUT THE
NEED FOR A MARINE HEADLINE.
CLE WATCHES/WARNINGS/ADVISORIES
OH...LAKE EFFECT SNOW WARNING UNTIL 7 AM EST TUESDAY FOR OHZ011>014-
089.
PA...LAKE EFFECT SNOW WARNING UNTIL 7 AM EST TUESDAY FOR PAZ003.
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST TUESDAY FOR PAZ001-002.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST WEDNESDAY FOR LEZ145>149.
SYNOPSIS...CAMPBELL
NEAR TERM...CAMPBELL
SHORT TERM...SEFCOVIC
LONG TERM...SEFCOVIC
AVIATION...CAMPBELL
MARINE...SEFCOVIC
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