FXUS63 KLMK 290812
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
312 AM EST SUN NOV 29 2009
.SHORT TERM (TODAY - MONDAY)...
A FRONTAL BOUNDARY STRETCHING FROM SOUTHERN LAKE MICHIGAN TO
NORTHERN TEXAS THIS MORNING WILL BE THE FOCUS FOR PRECIPITATION IN
THE SHORT TERM PERIOD. THIS FRONT WILL MOVE EAST TODAY AND BE
KNOCKING ON OUR DOORSTEP BY THIS EVENING. EXPECT INCREASING CLOUDS
AND GUSTY WINDS AHEAD OF THIS SYSTEM. SW WINDS WILL GUST UP TO 20
TO 25 MPH TODAY. HIGH TEMPERATURES ARE EXPECTED TO TOP OUT IN THE
UPPER 50S OVER SOUTHERN INDIANA TO LOW 60S ELSEWHERE. WE SHOULD
START TO SEE A FEW STRAY SHOWERS OVER OUR FAR WESTERN COUNTIES BY
LATE THIS AFTERNOON/EARLY EVENING.
TONIGHT...THE FRONT WILL PASS THROUGH THE AREA BETWEEN 3Z TO 9Z
BRINGING WIDESPREAD RAIN. QPF AMOUNTS WILL GENERALLY RANGE FROM A
FEW HUNDREDTHS OF AN INCH UP TO A HALF INCH. COLDER AIR WILL BE
USHERED IN BEHIND THE FROPA ALLOWING TEMPS TO DROP INTO THE UPPER
30S OVER SOUTHERN INDIANA TO MID 40S IN THE LAKE CUMBERLAND REGION.
FOR MONDAY...EXPECT ANY STRAY SHOWERS ASSOCIATED WITH THE FROPA TO
BE OUT OF THE REGION BY EARLY AFTERNOON. THE COLDER AIR MASS OVER
OUR FORECAST AREA WILL HOLD HIGH TEMPS STEADY IN THE LOW TO MID 40S
FOR MONDAY.
.LONG TERM (MONDAY NIGHT - SATURDAY)...
THE FOCUS THIS PERIOD ON WED AND THU WITH OUR FIRST POTENTIAL
WINTER SYS POSSIBLY BRINGING MEASURABLE FROZEN PRECIP INTO OUR FA.
AS FOR NOW...THE BEST CHC AND TIMING FOR MEASURABLE SNOW LOOKS TO
BE ABOUT AN 8-HR PERIOD FROM 08Z-16Z THU ACROSS OUR NRN FA.
DETAILS:
BASED ON HPC INPUT AND RUN TO RUN CONSISTENCY...THE EURO AND
CANADIAN 00Z RUNS WILL PROVIDE THE MOST INPUT INTO THIS FCST.
BOTH MID RANGE MODELS START OFF WITH A CUTOFF COLD CORE LOW ACRS
SCNTRL TEXAS AT 12Z WED...MOVE IT NEWD INTO THE LOWER MS VLY BY WED
EVE AND TO THE TN VLY 12Z THU. THE CANADIAN IS A BIT MORE W/N WITH
ITS TRACK. ASSOCIATED SFC LOWS MOVE FROM THE SWRN GULF STATES (LA)
WED MRNG TO NRN MS WED EVE TO WEST VA-12Z THU. BASED ON GULF
MOISTURE TRANSPORT/INCREASING SYNPOTIC SCALE LIFT/CONVERGENCE...RAIN
WILL LIKELY OVERSPREAD OUR FA WED AFTN AND POSSIBLY CHANGE TO SNOW
(BASED ON THERMAL PROFILES)ACRS OUR NWRN/NRN COUNTIES IN THE 08Z-12Z
TIME FRAME AS SFC LOW MOVES FROM EKY INTO WEST VA. THIS TRANSITION
WOULD CONTINUE NW TO SE AS COLD AIR CONTINUES TO WRAP INTO THE
SYSTEM.
TEMPS ACRS OUR NRN FA...WHERE SNOW COULD BE FALLING...WOULD LIKELY
BE IN THE LOWER/MID 30S...A BIT WARM TO CAUSE MAJOR PROBS. CERTAINLY
WE WILL MONITOR THIS SYS CLOSELY AS ITS GETS NEARER. FOR NOW...WILL
INCREASE POPS FOR WED AFTN TO LIKELY...AT LEAST OVER THE SRN 2/3RDS
OF OUR FA AND CONTINUE INTO EARLY WED NIGHT. AFTERWARD...WILL LEAVE
CHC POPS FOR EARLY THU MRNG INTO MIDDAY WITH RAIN OR SNOW WORDING.
TOO EARLY TO GO WITH HIGHER POPS AND A DEFINITE PRECIP TRANSITION
WITH THE NAM AND ESPECIALLY THE GFS NOT ON BOARD WITH THIS SCENARIO.
&&
.AVIATION (06Z TAF ISSUANCE)...
VFR CONDITIONS WILL BE EXPECTED FOR MOST OF THIS TAF PERIOD. A COLD
FRONT WILL APPROACH THE AREA TONIGHT. AHEAD OF THE FRONT...THE SFC
PRESSURE GRADIENT WILL INCREASE TODAY CAUSING SW WINDS TO GUST UP TO
18 TO 22KTS THIS AFTERNOON AND EARLY EVENING. MID AND UPPER LEVEL
CLOUDS WILL BE ON THE INCREASE THIS AFTERNOON ALSO. FOR
TONIGHT...WE SHOULD SEE MOSTLY VCSH AHEAD OF THE FRONT THROUGH ABOUT
3Z-6Z. AROUND OR AFTER 6Z FLIGHT CONDITIONS WILL DROP INTO THE MVFR
CAT FOR CIGS/VSBYS AS MORE WIDESPREAD LIGHT TO MODERATE RAINFALL
ENTERS THE AREA AND PERSISTS THROUGH THE MORNING HOURS. THE FROPA
WIND SHIFT TO NW SHOULD OCCUR JUST BEYOND THIS TAF PERIOD IN THE
9Z-12Z TIME FRAME TOMORROW MORNING.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
SHORT TERM........AML
LONG TERM.........DK
AVIATION..........AML