ILN: Monday= Rain, Thursday= Snow for Dayton

[meso_jr]

Okay...what's this mean... what do you guys think? TWC, NWS, and local mets have rain to snow on Monday, with big snow on Thursday. Can you guys give me a clue as to what is going on with this week?

000
FXUS61 KILN 312003
AFDILN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
305 PM EST SAT JAN 31 2004

.SHORT TERM...
AT 19Z...ARCTIC HIGH PRESSURE WAS CENTERED ACROSS INDIANA AND OHIO.
THIS SFC HIGH WILL SLOWLY DRIFT OFF TO THE EAST OVERNIGHT. MAJOR
FCST PROBLEM IN THE SHORT TERM IN REGARDS TO TEMPS TONIGHT. MID AND
HIGH LVL CLOUDINESS WAS MOVING IN FROM THE WEST AS DEPICTED BY THE
IR SATELLITE IMAGERY. ATTM...SFC HIGH WILL BE PARKED ACROSS THE
AREA BETWEEN 00Z AND 06Z. IN ADDITION...TEMPS STILL COLD (FOR
EXAMPLE 10 TO 13 DEGREES AT NEWARK AND LANCASTER). HOW FAR TEMPS
DROP WILL DEPEND GREATLY ON THE THICKNESS OF THE CLOUD SHIELD. WILL
GO ON THE COLD SIDE TONIGHT...BUT TEMPS WILL HAVE TO BE WATCHED BY
EVENING FCSTER DUE TO THE UNCERTAINTY MENTIONED ABOVE.

ON SUNDAY...MID LVL RIDGE WILL BE IN PLACE WITH MID AND HIGH LVL
CLOUDINESS EXPECTED. TEMPS WILL BEGIN TO MODERATE.

NEXT STORM SYSTEM TO AFFECT THE REGION IS POISED TO MOVE IN LATE ON
MONDAY...LASTING INTO TUESDAY. ETA/GFS SLOWER WITH THE PROGRESSION
OF THE SYSTEM AND THE ONSET OF PCPN. AS A RESULT...BELIEVE TEMPS
WILL WARM UP ENOUGH ALL LOCATIONS BY MONDAY AFTERNOON...AND STAY
WARM ENOUGH FOR MOST OF MONDAY NIGHT THAT PCPN WILL BE IN THE LIQUID
FORM. AS SFC LOW AND COLD FRONT PIVOT THROUGH DURING THE MORNING ON
TUESDAY...TEMPS WILL DROP OFF SLIGHTLY...AND PCPN SHOULD CHANGE TO
SNOW.

WENT CLOSE TO THE MAV GUIDANCE SUNDAY THROUGH TUESDAY.


.LONG TERM...
FORECAST CONCERN IN THE LONG TERM REVOLVES AROUND WEATHER SYSTEM
APPROACHING FOR LATE IN THE WORK WEEK. 00Z/31 AND 06Z/31 GFS WERE IN
PRETTY GOOD AGREEMENT WITH 12Z/30 ECMWF...WITH SFC LOW FURTHER SOUTH
ACROSS LOWER MISSISSIPPI VALLEY AT 12Z THURSDAY THAN PREVIOUS
RUNS...ALTHOUGH THE ECMWF WAS A LITTLE FARTHER SOUTH AND WEAKER. NOW
IT LOOKS LIKE THE 12Z/31 GFS HAS TRENDED WEAKER AND A LITTLE FARTHER
SOUTH TOO. WITH FARTHER SOUTH SOLUTION...INVERTED TROF FORECAST TO
PUSH ACROSS OUR REGION THURSDAY AND FRIDAY. THIS IS USUALLY A
FAVORABLE SET UP FOR SNOW ACROSS OUR REGION AS WARMER AIR NOT ABLE
TO MAKE IT UP AS FAR NORTH INTO OHIO VALLEY. EVEN THICKNESS
SCHEMES OFF WARMER 00Z GFS SOLUTION INDICATING MOSTLY SNOW ACROSS
OUR AREA WITH A POSSIBLE MIX ACROSS THE SOUTHEAST FOR A BRIEF PERIOD
OF TIME THURSDAY AFTERNOON. HAVE THEREFORE KEPT PCPN TYPE MAINLY IN
THE FORM OF SNOW FOR THURSDAY INTO FRIDAY NIGHT AND TRENDED TEMPS A
LITTLE COOLER THAN GUIDANCE.

[Guest]

I wouldnt bet the farm on this. You know how the Offices here in this state are. CONSERVATIVE!

[polarbear]

Right now it looks like the precipitation may start Monday morning in the Cincinnati and Dayton areas as freezing rain, but change to rain in the afternoon as the surface temperatures rise above freezing. Model guidance disagree with how warm that will be. Eta is colder than the GFS, mainly because the Eta shows a weaker surface low tracking through Indiana Monday night, while the GFS is warmer and shows a stronger low (stronger southeasterly flow). Either way, temperatures look to drop below freezing late Monday night or Tuesday morning, changing the precip back to snow. How soon this occurs will dictate how much snow falls. Right now the snow accumulation doesn't look significant (few inches).

Satellite shows snow cover still over all of Ohio/Indiana and the northwestern 1/4 of Kentucky. I'm unsure how much this may affect the wamer air trying to advect northward. Seven inches remains on the ground here.

For the late week storm, right now it looks like the thermal profile will remain cold enough for an all snow event, with accumulations possible. How much is a question too soon to answer.