Flash Flood Warning 68, NWS Jackson, KY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON KY
320 AM EDT SAT JUL 20 2002

06Z SFC ANALYSIS SHOWS LOW PRESSURE OFF THE MID ATLANTIC SEABOARD
AND OVER THE HIGH PLAINS. A SLOWLY SINKING FRONTAL BOUNDARY CONNECTS
THESE TWO CURRENTLY LYING JUST NORTH OF THE OHIO RIVER...HOWEVER...
YOU HAVE TO GO UP INTO MICHIGAN AND NORTHERN ILLINOIS TO SEE
DEWPOINTS LOWER THAN THE UPPER 60S AND LOWER 70S. WIDELY SCATTERED
SHOWERS CONTINUE SOUTH OF THIS FRONT...LIKEWISE ACCOMPANIED BY SOME
LOW AND MID LEVEL CLOUDINESS.

THE MODELS ARE IN BROAD AGREEMENT ALOFT FINALLY SHIFTING THE PESKY
UPPER LOW EAST TODAY AS THE WESTERLIES PUSH THE NORTHEAST TROUGH OFF
SHORE. WEAK RIDGING THEN MOVES INTO THE OHIO VALLEY BEFORE IT TOO
SUCCUMBS TO THE NEXT RIPPLE IN THE JET STREAM MOVING INTO THE GREAT
LAKES LATE MONDAY. THIS TROUGH WILL BUILD SOUTHEAST BY MIDWEEK WHILE
STRONG RIDGING REASSERTS ITSELF OVER THE FOUR CORNERS REGION.

FOR SENSIBLE WEATHER...THE WEAK FRONT WILL PRESS SOUTH TODAY INTO A
JUICY AIR MASS THAT SHOULD BE ENOUGH TO CONTINUE SCATTERED SHOWERS
AND THUNDERSTORMS THROUGH THE MORNING. HOWEVER...AT THE TIME OF
PEAK HEATING THE FORECAST SOUNDINGS INDICATE A DRIER COLUMN OF AIR
WITH PWS DROPPING BELOW 1.5 INCHES. WILL NOT LIMIT THE CHANCES TO
THE MORNING...ALTHOUGH WILL PLACE LOWER POPS NORTH FOR THE WHOLE
DAY. DRIER AIR IN PLACE AND A DEVELOPING MID LEVEL CAP WILL KEEP
POPS IN CHECK THROUGH MONDAY BEFORE ANOTHER FRONT APPROACHES. BY
THAT TIME...TUESDAY...WE WILL HAVE HAD A CHANCE TO REMOISTEN AND AT
LEAST CHANCE POPS LOOK IN ORDER. WILL NOT BITE ON THE CLEAN FROPA
PORTRAYED IN THE AVN FOR MIDWEEK...YET. TEMPERATURES SUNDAY AND
MONDAY WILL APPROACH 90 DEGREES THANKS TO DRIER AIR AND FEWER CLOUDS
MORE NORMAL READINGS FOLLOW FOR THE REST OF THE WEEK.

NGM AND AVN MOS ARE SIMILAR WITH RESPECT TO TEMPERATURES. WILL USE A
BLEND. ON POPS...PREFER THE WETTER AVN FOR TODAY WITH THE REST OF
THE WEEKEND DRY.

AS FOR GFE/IFPS: STANDARD LOAD OF MESOETA TEMPS/WINDS THROUGH 60
HOURS THEN TWEAKING OF THE REST...DRIER/CLEARER SATURDAY NIGHT
THROUGH TUESDAY MORNING THAN PREVIOUS PACKAGE.

WORK ZONES AVAILABLE BEFORE TOO LONG UNDER THE AFOS PRODUCT
SDFOZFJKL.

PRELIMINARY CCF:
LOZ EB 085/067 090/068 090 311-2
JKL EB 084/069 090/070 090 4---1

.JKL...NONE.

GREIF

PREVIOUS DISCUSSIONS FOLLOW:
===================================================================

930 PM EDT FRI JUL 19 2002

...FORECAST ISSUES...
CONTINUE TO HAVE CONVECTIVE DEVELOPMENT ALONG AND AHEAD OF OUTFLOW
FROM PREVIOUS CONVECTION IN OHIO. THIS HANDLED WELL BY THE MESO ETA.
TOO MANY BOUNDARIES TO RULE OUT CONVECTIVE DEVELOPMENT OVERNIGHT.

FEEL THAT THE CURRENT FORECAST ON TRACK. FOR NOW WILL NOT PLAN ON
UPDATE TO THE FORECAST.

.JKL...NONE.
LEWIS
===================================================================

232 PM EDT FRI JUL 19 2002

...FORECAST ISSUES...
PRECIPITATION CHANCES IN THE EARLY PART OF THE SHORT TERM (TONIGHT
THROUGH SATURDAY) AND ITS EFFECTS ON TEMPS TONIGHT AND TOMORROW.
ALSO PRECIP CHANCES ON MONDAY ARE IN QUESTION AS WELL.

...MODELS/ZFP...
MODELS IN GENERAL AGREEMENT WITH THE WEATHER PATTERN IN THE SHORT
TERM.  MODELS NOW COMING INTO AGREEMENT WITH PUSHING FRONTAL
BOUNDARY THROUGH THE REGION DURING THE DAY TOMORROW.  FORECAST
CONCERNS RIGHT NOW ARE RAIN CHANCES THIS EVENING AND FOR SATURDAY.
HAVE BEEN WATCHING THE RADAR THIS AFTERNOON AND IT LOOKS LIKE MOST
OF THE PRECIPITATION WILL FALL OVER THE NORTHERN PART OF THE CWA
THIS EVENING.  INITIALLY THOUGHT ABOUT A 40 POP ACROSS THE
BOARD...BUT NOW PLANNING ON GOING WITH 40 POPS NORTH AND 30 POPS
ACROSS THE SOUTH.  WILL KEEP AN EYE ON THE RADAR AND IF THINGS START
TO FILL IN WILL ADJUST POPS UPWARD ACROSS THE SOUTH.

FOR SATURDAY...PLAN ON JUST INVERTING POPS (40 SOUTH AND 30 NORTH)
AS BOUNDARY PUSHES THROUGH THE AREA.  SHOULD SEE SOME PARTIAL
CLEARING SAT NIGHT AND THEN A PARTLY SUNNY AND VERY WARM DAY FOR
SUNDAY.  FWC/MAV/MEX GUIDANCE NOT IN VERY GOOD AGREEMENT FOR THIS GO
AROUND.  AT THIS TIME...PLAN ON STAYING CLOSER TO MAV NUMBERS...BUT
A MAV/FWC BLEND WILL BE USED TOWARD THE END OF THE SHORT TERM PERIOD.

...EXTENDED...
AGAIN NOT MUCH CHANGE IN THE EXTENDED.  NEW 00Z RUN FROM THIS
MORNING CONTINUES TO SHOW RELATIVELY PROGRESSIVE FLOW ACROSS THE
CONUS WITH UPPER LEVEL RIDGE OUT OVER THE WEST.  SEVERAL H5 WAVES
ARE FORECAST TO SCOOT ALONG IN THE MEAN FLOW THROUGH MUCH OF THE
EXTENDED...ALTHOUGH TIMING OF EACH INDIVIDUAL WAVE IS IN QUESTION.
AT THE SURFACE...WAVY FRONTAL BOUNDARY IS FORECAST TO SETTLE SLOWLY
THROUGH THE REGION THROUGH MIDWEEK.  BOUNDARY LOOKS TO BE SOUTH OF
KY BY THURSDAY...WITH ANOTHER FRONTAL BOUNDARY MAKING ITS WAY TOWARD
THE OHIO VALLEY BY FRIDAY.  THE COMBINATION OF THE SURFACE FRONTAL
BOUNDARY ALONG WITH UPPER LEVEL WAVES PASSING BY WILL LIKELY YIELD A
CHANCE OF AFTERNOON/EVENING CONVECTION ACROSS THE AREA.  NO BIG
DIFFERENCES IN TEMPERATURES FROM YESTERDAYS RUN.  TEMPERATURES LOOK
TO BE SLIGHTLY COOLER FOR TUESDAY AND WEDNESDAY DUE CLOUDS AND RAIN
WITH SURFACE FRONTAL BOUNDARY IN THE AREA.  TEMPS THEN LOOK TO
MODERATE TOWARDS WEEKS END.

...IFPS/GRIDS...
DATABASE IN GOOD SHAPE.  DID THE USUAL RELOAD OF ONE HOUR T/TD,
WINDS FROM THE MESO ETA.  ONLY MINOR TWEAKS DONE TO EXISTING
DATABASE TO REFLECT ABOVE THOUGHTS AND UPCOMING FORECAST.

...PRELIM NUMBERS...
LOZ 68/85 67/89 3412
JKL 67/84 68/89 4311

.JKL...NONE

JARVIS