Good evening folks. I wanted to get a quick update out before I head out to watch my daughter perform with the Russian Ballet in the Nutcracker. This update is for the burst of snow tonight and the Winter Storm Threat for Christmas.

A streak of light snow with a touch of freezing rain will develop this evening across parts of central and northern Kentucky. This can lay down a coating to one inch of snow for some areas along and north of I-64  especially. Track the action here…



Most of the stuff will change over to some drizzle or VERY light rain for Tuesday as temps head into the low and mid 30s in these areas. Watch for another possible light snowfall later Wednesday into Wednesday night.

The Christmas Winter Storm THREAT continues for the region. Several of the models went with a southern track giving the state a light to moderate snowfall. I think those models are too far south. The new GFS comes in with something closer to my thoughts in terms of track… but is likely light in the precip department. Here is what it shows..

Friday Afternoon



Christmas Eve


Friday Night


Christmas Morning



Our buddy MJ from the NWS Louisville has a good discussion on the possible storm…

…SIGNIFICANT WINTER STORM TO IMPACT THE REGION CHRISTMAS EVE AND
CHRISTMAS DAY…

WEDNESDAY THROUGH THURSDAY…

REGION WILL START OFF WITHIN NORTHWEST FLOW ON WEDNESDAY AS
DEPARTING SYSTEM CONTINUES TO HEAD OFF TO THE EAST. ENOUGH OF A
FETCH OFF THE LAKES SHOULD RESULT IN SCATTERED FLURRIES ACROSS
EXTREME SOUTHEAST INDIANA AND THE BLUEGRASS REGION ON
WEDNESDAY…WHILE THE REST OF THE AREA REMAINS DRY.  HIGHS WEDNESDAY
LOOK TO WARM INTO THE LOWER-MID 30S IN THE NORTH AND
NORTHEAST…WITH MID TO UPPER 30S ACROSS CENTRAL AND SOUTHERN KY.
DRY CONDITIONS ARE EXPECTED ON THURSDAY AS RIDGING BUILDS OVER THE
AREA AS THE NEXT STORM APPROACHES FROM THE WEST.  HIGHS WILL BE
SIMILAR TO THOSE ON WEDNESDAY WITH HIGHS IN THE MID 30S IN THE NORTH
AND UPPER 30S TO AROUND 40 IN SOUTHERN KY.

THURSDAY NIGHT THROUGH CHRISTMAS NIGHT…

LATEST SUITE OF MED/LONG RANGE DETERMINISTIC AND ENSEMBLE MODEL RUNS
CONTINUE TO AGREE THAT A MID-LEVEL WAVE WILL EJECT OUT OF THE
SOUTHERN ROCKIES AND INTO THE SOUTHERN PLAINS THURSDAY EVENING.
OVERALL…THE MAJORITY OF THE MODEL GUIDANCE HAS DONE TWO
THINGS…FIRST…THEY HAVE ALL SLOWED DOWN THE EASTWARD PROGRESSION
OF THE SYSTEM A BIT…AND SECOND…THE OVERALL TRACK OF THE SYSTEM
HAS COME IN A BIT MORE SOUTH.  SINCE THE CONSENSUS OF THE MODELS
HAVE TRENDED A BIT FURTHER SOUTH…THEIR OVERALL THERMAL PROFILES
ACROSS OUR AREA ARE A BIT COLDER IN TODAY RUNS.

THERE REMAINS CONSIDERABLE SPREAD AMONG THE DETERMINISTIC GUIDANCE
AND THE ENSEMBLE SOLUTIONS FROM BOTH THE GFS AND EURO ALSO EXHIBIT A
BIT OF SPREAD IN THEIR SURFACE LOW TRACK SOLUTIONS.  CURRENTLY THE
GFS AND ITS ENSEMBLES ARE ON THE NORTH SIDE OF THE GUIDANCE WHILE
THE EURO AND CANADIAN GEM RUNS ARE ON THE SOUTHERN EDGE OF THE
GUIDANCE ENVELOPE.  CURRENTLY…THE ENSEMBLE SOLUTIONS FROM BOTH THE
GFS AND EURO DO NOT FULLY SUPPORT THE CAN GEM AND EURO FAR SOUTHERN
SOLUTIONS. IN ADDITION…LOOKING AT THE GLOBAL PATTERN…IT APPEARS
THAT THE NORTHERN STREAM OF THE JET SHOULD REMAIN A BIT STRONGER
THAN THE SOUTHERN STREAM.  THUS…FEEL THAT THE GEM/EURO SOLUTION IS
TOO FAR SOUTH AND HAVE GONE MORE THE 12Z GFS ENSEMBLE MEAN FOR A
TRACK SOLUTION AT THIS TIME.  WITH THAT SAID…WILL NEED TO MAKE A
FEW ADJUSTMENTS TO THE FCST.

FOR THU NIGHT…CLOUDS WILL CONTINUE TO STREAM IN FROM THE WEST AS
THE STORM DEVELOPS OVER THE SOUTHERN PLAINS AND HEADS EAST.
PRECIPITATION WILL BREAK OUT ACROSS THE REGION LATE THURSDAY
NIGHT…BUT PROBABLY MORE LIKELY FRIDAY MORNING IN THE WEST AND THEN
SPREAD EAST DURING THE DAY.  BOUNDARY LAYER TEMPERATURES HAVE COOLED
IN THE MOST RECENT RUNS…BUT FEEL THAT A RAIN/SNOW MIX IS STILL
LIKELY ON FRIDAY DURING THE DAY.  MUCH COLDER AIR WILL DUMP INTO THE
REGION EARLY CHRISTMAS TRANSITIONING THE PRECIPITATION FROM
RAIN/SNOW OVER TO PLAIN SNOW WHICH SHOULD CONTINUE OVERNIGHT AND
INTO CHRISTMAS DAY.  SO A WHITE CHRISTMAS LOOKS VERY LIKELY AT THIS
TIME.  IN ADDITION…THE INCREASING PRESSURE GRADIENT WILL RESULT IN
WINDY CONDITIONS WHICH MAY RESULT IN SOME BLOWING SNOW AT TIMES.

AS FOR AMOUNTS…AM NOT GOING TO SPECULATE ON AMOUNTS AS THE EXACT
TRACK OF THIS STORM IS STILL UNCERTAIN.  HOWEVER…GIVEN THE COLDER
SOLUTIONS IN THE MODELS…IT APPEARS THAT MORE FROZEN PRECIPITATION
IS LIKELY THAN LIQUID PRECIPITATION.  SOME ACCUMULATION OF SNOW IS
LIKELY BEGINNING LATE CHRISTMAS EVE AND CONTINUING THROUGH CHRISTMAS
DAY.  HOWEVER A SHIFT IN THE TRACK TO THE NORTH OR SOUTH WILL
HEAVILY AFFECT PRECIPITATION AMOUNTS.

GIVEN THAT THIS STORM WILL BE AFFECTING US DURING A PEAK TRAVEL
PERIOD…PEOPLE WITH TRAVEL PLANS THIS FOR THE HOLIDAY SHOULD KEEP
ABREAST OF THE LATEST FORECASTS OVER THE NEXT SEVERAL DAYS…AND BE
PREPARED TO MAKE ALTERNATE TRAVEL PLANS SHOULD TRAVEL BECOME
NEGATIVELY IMPACTED CHRISTMAS EVE AND CHRISTMAS DAY.  STAY TUNED!

I hope to have a late evening update with a full post coming later tonight. Take care.