Area Forecast Discussion
Issued by NWS Jackson, KY

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS63 KJKL 132042 AFDJKL AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE JACKSON KY 342 PM EST SAT FEB 13 2016 .SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT) ISSUED AT 342 PM EST SAT FEB 13 2016 AS HIGH PRESSURE MOVED INTO THE REGION FROM THE NW TODAY...MUCH OF EASTERN KY EXPERIENCED NW FLOW...ENHANCED IN THE MID AND UPPER LEVELS BY A STRONG UPPER LEVEL TROUGHING PATTERN. THIS NW FLOW ALLOWED MOISTURE FROM LAKE MICHIGAN TO FLOW AS FAR SOUTH AS EASTERN KY...AND RESULTED IN SCATTERED PATCHES OF SNOW FLURRIES THROUGHOUT THE DAY...ESPECIALLY ACROSS THE NORTHERN AND FAR EASTERN CWA. AS HIGH PRESSURE SETTLES IN CLOSER TO THE REGION THIS AFTERNOON...WINDS WILL CONTINUE TO LIGHTEN AND PREVENT BEST MOISTURE FROM PROTRUDING SO FAR SOUTHWARD INTO THE OHIO VALLEY...CUTTING OFF ANY FURTHER FLURRY ACTIVITY. OTHERWISE...WITH HIGH PRESSURE PASSING OVERHEAD OVERNIGHT...THE MAIN ELEMENT OF CONCERN WILL BE TEMPERATURES. STRONG NW TO SE FLOW IN THE MID AND UPPER LEVELS WILL CONTINUE TO PULL DRIER BUT MUCH COLDER ARCTIC AIR INTO THE REGION. WITH MOSTLY CLEAR TO PARTLY CLOUDY SKIES EXPECTED THROUGH THE FIRST PART OF THE NIGHT...STRONG SUBSIDENCE WILL FORM...AND MAXIMUM RADIATIONAL COOLING WILL ENSUE. IT IS LIKELY THAT MANY OF THE DEEPER VALLEYS WILL SEE SINGLE DIGIT TEMPERATURES BY DAWN ON SUNDAY...WHILE MOST OF THE RIDGES WILL BE LUCKY TO SEE THE TEENS. THIS COUPLED WITH LIGHT WINDS COULD RESULT IN WIND CHILLS AROUND 0 OR EVEN SEVERAL DEGREES BELOW IN SOME LOCATIONS. BEHIND THE EXITING HIGH PRESSURE ON SUNDAY...WINDS WILL BECOME MORE SOUTHERLY...WITH TEMPERATURES RISING BACK INTO THE MID 20S TO LOW 30S. MEANWHILE...AN UPPER LEVEL WAVE WILL BEGIN STRENGTHENING ACROSS THE UPPER MIDWEST...MOVING EASTWARD TOWARDS THE MISSISSIPPI RIVER VALLEY DURING THE DAY. VEERING SURFACE WINDS IN WAKE OF THE DEPARTING RIDGE WILL USHER IN WARMER AIR ALOFT LATER TONIGHT INTO SUNDAY. THIS WILL HELP DRAW A STREAM OF GULF MOISTURE NORTH AHEAD OF THIS UPPER DISTURBANCE. TOP-DOWN MOISTENING WILL LEAD TO INCREASING HIGH-MID CLOUD COVER FROM LATE TONIGHT THROUGH THE DAY SUNDAY...BEFORE LOW CLOUDS AND RESULTING SNOW COMMENCES SUNDAY AFTERNOON. AS TEMPERATURES FALL SEVERAL DEGREES SUNDAY NIGHT...WE CAN PRETTY MUCH ENSURE THAT ALL PRECIPITATION BETWEEN SUNDAY AFTERNOON AND MONDAY MORNING WILL FALL IN THE FORM OF SNOW. THE NAM CONTINUES TO BE THE MOST AGGRESSIVE ON TIMING...AND THE OUTLIER AS SUCH...SO TRENDED MORE TOWARDS A ECMWF AND GFS SOLUTION FOR BOTH TIMING AND SNOW RATIOS. GENERALLY AGREED WITH WPC QPF GUIDANCE...WHICH WHEN PAIRED WITH FORECASTED SNOW RATIOS...RESULTED IN TOTAL SNOWFALL ACROSS THE REGION BETWEEN SUNDAY AFTERNOON AND MONDAY MORNING IN THE 2.5 TO 4.5 RANGE. DUE TO THE ELONGATED NEARLY 24 HOUR TIME PERIOD OF SNOW...THIS ONLY FALLS INTO ADVISORY CRITERIA. AFTER SOME GOOD COLLABORATION WITH NEIGHBORING OFFICES...WE DECIDED TO HOIST OUR ADVISORY WITH A START TIME OF 18Z SUNDAY...AND ENDING 15Z MONDAY. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 419 AM EST SAT FEB 13 2016 THE PERIOD WILL BEGIN WITH A APPROACHING UPPER LEVEL WAVE AND ISENTROPIC LIFT POTENTIAL FOR SUNDAY NIGHT INTO MONDAY. CONFIDENCE CONTINUES TO INCREASE THAT THIS WILL START...AS ALL SNOW ACROSS THE REGION BASED ON TIME HEIGHTS AND FORECAST SOUNDINGS. GIVEN THE INCREASED CONFIDENCE BUT STILL LATER PERIOD WILL GO WITH SPS IN COORDINATION WITH SURROUNDING OFFICES. THINK HEADLINES ARE CERTAINLY POSSIBLE IF TRENDS CONTINUE WITH LATER MODEL RUNS. OVERALL RIGHT NOW LOOKING AT 2-4 INCHES WITHIN THE PERIOD FROM SUNDAY INTO EARLY MONDAY. MODELS DO SUGGEST POTENTIAL FOR A DEFORMATION ZONE...HOWEVER LOCATION UNCERTAINTIES STILL EXIST AND THIS WOULD HAVE MAJOR IMPLICATIONS OF SNOW AMOUNTS. AFTER THIS MODELS REMAIN ALL OVER THE PLACE RUN TO RUN...WILL SAY A GOOD PORTION OF THE LATEST MODEL SUITE HAS TRENDED IN TRACKING A SURFACE LOW ACROSS THE TN VALLEY MONDAY AFTERNOON. THIS WOULD APPEAR TO SPELL A BIT MORE IN THE WAY OF POTENTIAL MIXING TO ALL RAIN ON MONDAY AFTERNOON FOR MOST OF THE REGION...WITH EVEN SOME OF THE FORECAST SOUNDINGS LOOSING ICE. RIGHT NOW WILL LEAN AWAY FROM THE COOLER 00Z NAM...GIVEN IT SEEMS TO BE THE OUTLIER IN RELATIONS TO IT/S PROGRESSIVE NATURE. AFTER THIS LOW SWINGS NE OF THE REGION AND COLD AIR WILL ADVECT IN ON THE BACKSIDE...THIS WILL LEAD TO YET ANOTHER CHANGE OVER BACK TO SNOW MONDAY NIGHT. RIGHT NOW KEEPING THE RATIOS LOWER HERE AND BETTER QPF LINES ALONG OUR VA BORDER. THEREFORE RIGHT NOW THINKING LIGHTER ACCUMULATIONS FOR THAT PERIOD...HOWEVER CONFIDENCE REMAINS QUITE LOW. THAT SYSTEM WILL EXIT TO THE NE...WHILE ANOTHER WAVE RIDES THE COAT TAILS AND IS POISED TO BRING ANOTHER SURFACE LOW SE ACROSS THE REGION. ONCE AGAIN MODELS ARE IN A FAIR AMOUNT OF DISAGREEMENT ON TIMING AND PLACEMENT OF THIS SYSTEM...POP WISE LEANED TOWARD THE MODEL BLEND. DOES LOOK LIKE ENOUGH WARM AIR WILL BE IN PLACE TO LEAD TO A CHANGE OVER TO ALL RAIN TUESDAY AND BACK TO SNOW TUESDAY NIGHT. HOWEVER TIMING AND LOCATION WILL PLAY A CRITICAL ROLE IN PRECIP TYPES FOR THIS SYSTEM. HIGH PRESSURE WILL PROGRESS ACROSS THE OHIO VALLEY AND INTO THE MID ATLANTIC BY THE END OF THE PERIOD. THIS WILL BRING RETURN FLOW AND COUPLED WITH RISING HEIGHTS WILL LEAD TO MODERATING TEMPS. MATTER OF FACT BLENDS WOULD SUGGEST TEMPS ON FRIDAY MAY BE ABLE TO CLIMB INTO THE LOWER 60S IN SOME SPOTS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1223 PM EST SAT FEB 13 2016 HIGH PRESSURE WILL CONTINUE TO MOVE INTO THE REGION TODAY...PROMOTING NW FLOW BUT KEEPING WINDS GENERALLY LESS THAN 10 KNOTS AS WE CONTINUE TO LOSE PRESSURE GRADIENTS. AS A RESULT OF THIS NW FLOW...WE ARE STILL TAPPING INTO SOME MOISTURE COMING OFF OF LAKE MICHIGAN...WHICH WILL PROMOTE SNOW FLURRY ACTIVITY THROUGHOUT THE AFTERNOON ACROSS PORTIONS OF EASTERN KY...MAINLY AT KSJS... KSYM...AND POSSIBLY KJKL. OTHERWISE...VFR CONDITIONS SHOULD REMAIN IN CONTROL AS WE HEAD INTO THE OVERNIGHT. NW WINDS WILL VEER NORTHEASTERLY THIS EVENING AND TONIGHT AS HIGH-MID CLOUDS GRADUALLY LOWER THROUGH 12Z SUNDAY IN RESPONSE TO AN APPROACHING SYSTEM TO OUR WEST. WHILE VFR CONDITIONS WILL LIKELY BE IN PLACE THROUGH SUNDAY MORNING...EXPECT DETERIORATING CONDITIONS THROUGHOUT THE DAY AS SNOW STARTS TO MOVE INTO THE REGION && .JKL WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 1 PM SUNDAY TO 10 AM EST MONDAY FOR KYZ044-050>052-058>060-068-069-079-080-083>088-104-106>120. && $$ SHORT TERM...JMW LONG TERM...DJ AVIATION...JMW

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.