000
FXUS63 KPAH 281145
AFDPAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PADUCAH KY
545 AM CST SAT FEB 28 2015

.UPDATE...
ISSUED AT 545 AM CST SAT FEB 28 2015

THE AVIATION SECTION HAS BEEN UPDATED FOR THE 12Z TAF ISSUANCE.

&&

.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 351 AM CST SAT FEB 28 2015

WILL BE ISSUING A WINTER WEATHER ADVISORY FOR AREAS ALONG AND
NORTH OF A LINE FROM ELLSINORE IN CARTER COUNTY MISSOURI...TO
MARION AND GRAYVILLE ILLINOIS...AS WELL AS GIBSON AND PIKE
COUNTIES IN SOUTHWEST INDIANA. TOTAL SNOWFALL ACCUMULATIONS HAVE
A RATHER SHARP GRADIENT FROM SOUTHEAST TO NORTHWEST...WHICH MADE
THE DECISION ON WHICH COUNTIES TO INCLUDE RATHER DIFFICULT. WILL
START THE ADVISORY AT 21Z TODAY FOR AREAS ALONG AND WEST OF THE
I-57...AND AT 00Z FARTHER TO THE EAST. IT WILL END AT 18Z SUNDAY
IN ALL AREAS.

MOST OF THE 00Z MODELS KEPT THE SURFACE RIDGE NOSING SOUTHWEST
ACROSS SOUTHERN ILLINOIS AND SOUTHEAST MISSOURI THROUGH AT LEAST
12Z SUNDAY. THEY ALSO REALLY STRUGGLE TO BRING ANY SIGNIFICANT
SOUTHEASTERLY WINDS INTO THE REGION...DUE TO A VERY FLAT PRESSURE
PATTERN. ALL OF THIS LEADS US TO BELIEVE THAT TEMPERATURES ARE
GOING TO STRUGGLE TO CLIMB ABOVE FREEZING OVER MOST OF THE
ADVISORY AREA UNTIL POTENTIALLY SUNDAY AFTERNOON. USED THE
CONSENSUS OF RAW MODEL TEMPERATURES FOR TRENDS SATURDAY NIGHT
THROUGH SUNDAY.

USED THE 00Z GFS SOUNDINGS AS A GUIDE FOR PRECIPITATION TYPE
DECISIONS THROUGH THE EVENT. DEFINITELY TRENDED COOLER WITH THE
SOLUTION WITH MORE SNOW THAN FREEZING RAIN. DID ACCUMULATE A FEW
HUNDREDTHS OF ICE IN THE ADVISORY AREA...BUT THAT WILL FALL ON TOP
OF THE SNOW ACCUMULATIONS THAT WILL RANGE FROM 2-4 INCHES. THE
GREATEST AMOUNTS WILL BE ACROSS PERRY...JEFFERSON...AND WAYNE
COUNTIES IN ILLINOIS. SOME MINOR ICE AND SNOW ACCUMULATIONS ARE
LIKELY TO THE SOUTH OF THE ADVISORY...BUT WITH TEMPERATURES
WARMING MORE QUICKLY TOWARD FREEZING IN THOSE AREAS AND LESSER
QPF...ANY PROBLEMS ARE EXPECTED TO BE MINOR AND SHORT-LIVED.

THE 00Z MODELS ALSO SEEM TO BE EMPHASIZING THE NORTHERN THIRD TO
HALF OF THE AREA FOR STEADIER PRECIPITATION THROUGH THE EVENT.
WOULD NOT RULE OUT A SOUTHWARD SHIFT...WHICH COULD RESULT IN
CHANGES TO THE ADVISORY AREA. ALSO...WOULD NOT BE SURPRISED IF
WARMING OCCURS A BIT FASTER THAN CURRENTLY EXPECTED...SO THAT
COULD ALSO IMPACT THE AREA AND TIMING OF THE ADVISORY AREA.
CONFIDENCE IS NOT GREAT IN THE DETAILS OF THIS EVENT.

MOST GUIDANCE PUSHES THE PRECIPITATION OUT OF THE AREA QUICKLY
SUNDAY EVENING. PROBABLY HAVE TO MUCH POP IN THE FORECAST FOR
SUNDAY NIGHT. WENT DRY ON MONDAY...AS NO GUIDANCE HAS ANY QPF FOR
OUR AREA. CANNOT RULE OUT A BRIEF CHANGE OVER TO SLEET...FREEZING
RAIN OR EVEN SNOW BEFORE THE PRECIPITATION COMES TO AN END SUNDAY
NIGHT...BUT REALLY THINK THE PRECIPITATION WILL BE DONE BEFORE
THAT CAN HAPPEN.

ALTHOUGH TEMPERATURES WILL FALL BACK BELOW FREEZING OVER MUCH OF
THE AREA SUNDAY NIGHT...THERE IS NO SIGN OF ARCTIC AIR. HIGHS ON
MONDAY ARE ABOVE FREEZING FOR THE ENTIRE AREA AND INTO THE LOWER
40S ACROSS THE SOUTHERN THIRD OF THE AREA.

.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 351 AM CST SAT FEB 28 2015

AFTER A BRIEF REPRIEVE FROM THE ACTIVE WEATHER PATTERN...MORE
PRECIPITATION APPEARS LIKELY BEGINNING MONDAY NIGHT AND LASTING
THROUGH WEDNESDAY NIGHT WITH THE APPROACH AND PASSAGE OF OUR NEXT
SIGNIFICANT WEATHER SYSTEM. THUNDERSTORMS...HEAVY RAIN...AND MIXED
WINTRY PRECIPITATION WILL ALL BE POSSIBLE DURING THIS TIME.

LIGHT PRECIPITATION WILL LIKELY SPREAD ACROSS THE REGION MONDAY
NIGHT FROM WEST TO EAST. FORECAST TEMPERATURE PROFILES INDICATE MOST
OF THIS SHOULD BE IN THE FORM OF RAIN...THOUGH IT MAY BEGIN AS LIGHT
FREEZING RAIN OVER SOUTHWEST INDIANA AND NORTH OF ROUTE 13 IN
SOUTHERN ILLINOIS BEFORE TRANSITIONING TO RAIN LATER IN THE NIGHT.
ANY IMPACT SHOULD BE MINOR.

COPIOUS SUBTROPICAL MOISTURE WILL STREAM INTO THE REGION ON TUESDAY
AS A LOW PRESSURE SYSTEM OVER THE CENTRAL PLAINS ROCKETS NORTHEAST
INTO THE GREAT LAKES BY TUESDAY NIGHT. THIS WILL RESULT IN
WIDESPREAD RAIN. WITH PRECIPITABLE WATER VALUES IN EXCESS OF 1.5
INCHES AND ON THE HIGH END OF WHAT IS EXPECTED IN EARLY MARCH...
HEAVY RAIN IS QUITE POSSIBLE. WITH HIGHS TUESDAY AT LEAST IN THE 50S
AND POSSIBLY EVEN ABOVE 60...THE DEVELOPMENT OF AT LEAST ELEVATED
INSTABILITY WILL ALSO RESULT IN THE POTENTIAL FOR THUNDERSTORMS
TUESDAY INTO TUESDAY NIGHT.

THE PASSAGE OF A STRONG COLD FRONT WILL HERALD OUR NEXT ARCTIC BLAST
LATE TUESDAY NIGHT AND ESPECIALLY ON WEDNESDAY. AS TEMPERATURES FALL
THROUGHOUT THE DAY...ANY LINGERING PRECIPITATION WILL TRANSITION
SEQUENTIALLY FROM RAIN TO FREEZING RAIN...THEN SLEET...AND FINALLY
SNOW. EXACTLY HOW THIS UNFOLDS AND TO WHAT EXTENT IS TOO EARLY TO
ASCERTAIN AT THIS TIME. HOWEVER...POTENTIAL IMPACT TO TRAVEL WILL
NEED TO BE CLOSELY MONITORED AS WE GET CLOSER TO THE EVENT.

ANY LINGERING PRECIPITATION SHOULD TAPER OFF WEDNESDAY NIGHT...
LEAVING BITTERLY COLD ARCTIC AIR IN ITS WAKE. RIGHT NOW...WE HAVE
HIGHS BELOW FREEZING FORECAST FOR THURSDAY...WITH LOWS WEDNESDAY AND
THURSDAY NIGHTS IN THE TEENS. FORTUNATELY...THE END OF THE WEEK
LOOKS QUIET WITH AT LEAST SOME MODERATION IN TEMPERATURES.

&&

.AVIATION...
ISSUED AT 545 AM CST SAT FEB 28 2015

LOWER VFR CEILINGS WILL PERSIST FOR MUCH OF THE DAY UNTIL STEADY
MVFR SNOWS PUSH EASTWARD ACROSS THE REGION THIS EVENING. COULD SEE
MUCH OF THE INITIAL SNOWS TONIGHT STAY TO THE NORTH OF ALL TAF
SITES...BUT THE MAJORITY OF GUIDANCE DOES BRING IT INTO ALL SITES
THIS EVENING. GIVEN THE UNCERTAINTY...ONLY WENT WITH MVFR SNOW
INTIALLY. THE SNOW SHOULD CHANGE OVER TO FREEZING RAIN OR JUST
RAIN DEPENDING ON THE SURFACE TEMPERATURES OVERNIGHT. AS A WEAK
SURFACE TROUGH WASHES OUT OVER THE REGION LATE TONIGHT...WINDS
WILL BE NEARLY CALM AND CEILINGS WILL LIKELY DROP TO IFR LEVELS.
THIS WAS TIMED WITH THE CHANGE TO FZRA/RA IN THE TERMINALS.

&&

.PAH WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON CST
     SUNDAY FOR ILZ076>078-082-083-086.

     WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO NOON CST
     SUNDAY FOR ILZ075-080-081-084-085-088.

MO...WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO NOON CST
     SUNDAY FOR MOZ076-086-087-100-107.

IN...WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON CST
     SUNDAY FOR INZ081-082.

KY...NONE.
&&

$$

UPDATE...DRS
SHORT TERM...DRS
LONG TERM...RJP
AVIATION...DRS