FXUS63 KIND 290451
AFDIND
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
1151 PM EST SAT NOV 28 2009
.AVIATION...DISCUSSION FOR 6Z TAFS.
A LOW PRESSURE SYSTEM CURRENTLY IN OKLAHOMA WILL MOVE NORTHEAST
ALONG ITS FRONT BEFORE DRAGGING A COLD FRONT THROUGH CENTRAL INDIANA
SUNDAY EVENING. THIS WILL CAUSE CONDITIONS TO DETERIORATE AT THE
SITES BY TOMORROW AFTERNOON. KLAF WILL FALL FIRST AS IT WILL BE
CLOSEST TO THE TRACK OF THE LOW. EXPECTING MVFR CEILINGS TO START AT
KLAF BY AROUND 15Z AND SPREAD TO THE OTHER SITES OVER THE FEW HOURS
AFTER THAT. RAIN AND MVFR VISIBILITIES SHOULD BEGIN WITHIN A COUPLE
HOURS OF THE MVFR CEILINGS. IT IS POSSIBLE THAT CEILINGS WILL DROP
EVEN LOWER ONCE THE RAIN GETS GOING BUT CONFIDENCE IS NOT HIGH
ENOUGH TO INCLUDE IFR AT THIS TIME. WINDS WILL INCREASE AND SHIFT TO
THE WEST AND THEN NORTHWEST WITH FRONTAL PASSAGE IN THE 20-2Z
TIMEFRAME.
&&
.UPDATE...
HIGH PRESSURE CONTINUES TO DOMINATE INDIANAS WEATHER. SOME WARM AIR
ADVECTION OVERNIGHT SHOULD SLOW TEMPERATURE DECREASE. SKIES REMAIN
CLEAR AND GOING TEMPERATURE FORECAST LOOKS ON TRACK.
&&
.PREV DISCUSSION...A RIDGE OF HIGH PRESSURE WAS FOUND OVER EASTERN
OHIO AND EASTERN KENTUCKY EARLY THIS AFTERNOON...QUICKLY MOVING
EAST. LOW PRESSURE WAS FOUND OVER THE UP OF MICHIGAN AND A COLD
FRONT WAS EXTENDING SW ACROSS WISCONSIN TO CENTRAL IOWA AND CENTRAL
KANSAS. CURRENT RADAR MOSAICS SHOW NO PRECIPITATION ALONG THE FRONT.
MAIN CHALLENGE TONIGHT WILL BE POPS ON SUNDAY AFTERNOON AND SUNDAY
EVENING.
NAM AND GFS REMAIN IN PRETTY GOOD AGREEMENT AND WILL USE A BLEND.
TIME HEIGHT SECTIONS ACROSS THE AREA SHOW A DRY COLUMN TONIGHT WITH
DECENT SUBSIDENCE. CURRENT DEWPOINTS ACROSS THE AREA ARE IN THE
MIDDLE 30S. ALSO RADIATIONAL COOLING WON OUT LAST NIGHT. WITH CLEAR
SKIES AND LIGHT WINDS EXPECTED TONIGHT WILL LEAN 1-2 DEGREES COOLER
THAN MAVMOS FOR LOWS.
FORECAST SOUNDINGS BEGIN TO MOISTEN UP ON SUNDAY AS THE COLD FRONT
APPROACHES FROM THE NW. STRONGER UPPER DYNAMICS ALSO APPROACH ON
SUNDAY NIGHT. WEAK ISENTROPIC LIFT IS PRESENT...HOWEVER...LOWER
LEVEL Q VECTOR CONVERGENCE APPEARS MUCH MORE
FAVORABLE...PARTICULARLY DURING THE AFTERNOON. TIME HEIGHT SECTIONS
SHOW BEST VERTICAL VELOCITY NEAR 00Z MON. QUICK DRYING APPEARS TO
MOVE IN BEHIND THE FRONT ON SUNDAY NIGHT. GIVEN THE FAST FLOW
ALOFT...THIS SHUD BE A QUICK HITTING SYSTEM. FEEL HIGHLY CONFIDENT
THAT RAIN WILL OCCUR...BUT NOT VERY CONFIDENT AT ALL ON WHICH SIDE
OF 00Z IT WILL OCCUR. HENCE WILL STICK CLOSE ON POPS DURING SUNDAY
AFTERNOON AND SUNDAY EVENING. WILL RAISE POPS IN THE EVENING ACROSS
THE SOUTHEAST AS PROXIMITY TO THE SYSTEM PROGRESSION SEEMS TO POINT
TO BETTER CHANCES FOR RAIN THERE AFTER 00Z. GIVEN THE EXPECTED
INCREASE IN CLOUDS WILL GO AT OR BELOW MAVMOS HIGHS ON SUNDAY.
STRONG COLD AIR ADVECTION IN PLACE IN THE WAKE OF THE COLD FRONT
WITH H8 TEMPS FALLING TO NEAR -4C BY 12Z MONDAY. GIVEN THIS WL ALSO
GO AT OR BELOW MAVMOS FOR MONDAY MORNING LOWS.
DRY WEATHER WL REMAIN ON MONDAY AND MONDAY NIGHT AS A SURFACE RIDGE
BUILDS IN QUICKLY BEHIND THE FRONT AND UPPER TROUGH DEPARTS TO THE
EAST. THUS WILL AIR FOR A DECREASING CLOUDINESS TREND ALONG WITH
TEMPS AT OR BELOW MAVMOS DUE TO COLD H8 TEMPS NEAR -4C.
AT THE MOMENT IT APPEARS A QUICK MOVING UPPER SYSTEM WILL PUSH OUT
OF THE WESTERN GREAT LAKES ON TUESDAY...PERHAPS CLIPPING NORTHEAST
PARTS OF CENTRAL INDIANA. EITHER WAY...WL INCLUDE MORE CLOUDS ON
TUESDAY AND PERHAPS SOME LOW CHC POPS ACRS THE
MUNCIE...ANDERSON...WINCHESTER AREAS.
AS FOR THE EXTENDED...ECMWF AND GFS THEN HINTING AT A STRONGER STORM
COMING OUT OF THE SOUTHERN PLAINS ON WED THROUGH WED NIGHT. AT THIS
TIME H7 STORM TRACK IS OVER CENTRAL INDIANA WITH THE SURFACE LOW
TRAVERSING ACROSS KENTUCKY AND OHIO TO THE NORTHEAST. FORECAST
SOUNDINGS INDICATE THAT TEMPS APPEAR COLD ENOUGH FOR SNOW ON
WEDNESDAY NIGHT. STILL THIS IS DAY5 AND MODEL CONTINUITY IS A MAJOR
CONCERN. STILL SOME POPS ARE WARRANTED AT THIS POINT. BY THURSDAY
AND FRIDAY...BROAD...COLD CYCLONIC FLOW APPEARS TO DEVELOP ACROSS
THE EASTERN PARTS OF THE UNITED STATES. ALTHOUGH DEEP MOISTURE DOES
NOT APPEAR TO BE PRESENT...A FEW FLURRIES OR LIGHT SNOW CANNOT BE
RULED OUT GIVEN THE EXPECTED STRATUS AND PATTERN. HAVE TRENDED
TEMPERATURES COOLER THAN GUIDANCE GIVEN THE EXPECTED FLOW.
BY SATURDAY...UPPER LOW APPEARS TO MOVES WELL ENOUGH NORTHEAST THAT
THE PRECIPITATION CHANCES SEEM TO BE LIMITED BUT COLD FLOW WILL
REMAIN. ALL IN ALL A VERY INTERESTING PERIOD FOR THE END OF THE NEXT
WORKWEEK...BUT CONFIDENCE IS LOW AS WE WOULD LIKE TO SEE MORE RUN TO
RUN CONTINUITY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AVIATION...CP
PUBLIC...PUMA
UPDATE...SH
