000
FXUS63 KIWX 081850
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
150 PM EST SUN NOV 8 2009

.AVIATION...
LITTLE CONCERN THROUGH THE TAF PD WITH EXCEPTION OF POSSIBLE FOG
DEVELOPMENT AGAIN THIS MORNING AS DEWPOINTS THIS AFTERNOON ARE
ABOVE YESTERDAYS LEVELS AND WITH CLEAR SKIES EXPECTED TONIGHT PER
MODEL 850-500MB RH FIELDS...A PERIOD OF MVFR BR AGAIN LOOKS
POSSIBLE. OTHERWISE...HIGH CLOUDS THIS AFTERNOON GIVE WAY TO SKC
OVERNIGHT WITH LIGHT SOUTH WINDS AROUND 5KTS TONIGHT. CLOUDS
INCREASE ON MONDAY IN ADVANCE OF FRONTAL BOUNDARY POISED TO IMPACT
THE AREA BEYOND THE END OF THE TAF PD.

.PREV DISCUSSION... /ISSUED 1045 AM EST SUN NOV 8 2009/ 

UPDATE...

QUICK UPDATE TO REMOVE MORNING WORDING AS FOG HAS ESSENTIALLY
CLEARED THE AREA. CLEARED SKY GRIDS TO ZERO THROUGH MIDDAY AGAIN
PER SATELLITE OBSERVATIONS. AC DECK OVER ILLINOIS WILL BRING SOME
OPAQUE CLOUDINESS TO THE AREA THIS AFTERNOON BUT PERCENTAGE OF
OPAQUE SKY COVER WILL REMAIN LIMITED AND LIKELY OF LITTLE
CONSEQUENCE TO TEMPERATURES. SPEAKING OF...BUMPED TEMPS UP
GENERALLY 3 DEGREES ACROSS THE BOARD AS MIX DOWN TECHNIQUES FROM
H92 REVEAL TEMPS A LITTLE WARMER THAN 70 OVER MOST AREAS TODAY.
UPDATED GRIDS/ZONES ARE OUT.

PREV DISCUSSION... /ISSUED 450 AM EST SUN NOV 8 2009/

SHORT TERM...
ERLY AM WORDING FOR PTCHY GROUND FOG. VSBYS SHOULD REMAIN QUITE
VARIABLE OWING TO LACK OF FOG DEPTH. GRDL INCRS IN MIXING DEPTH TWRD
DAYBREAK IS ALSO PSBL AS PRES GRD ICRS. CONTD UPWARD TREND ON
TEMPS SPCLY DY1 WITH RELATIVELY WARM START AND 1000-850 THERMAL
AXIS TO SET UP FM CNTL MO TO NWRN PART OF CWA BY THIS EVENING WITH
PROJECTED MAX TEMPS HOLDING JUST BLO NOV 8 RECORDS. FAVOR A
SIMILAR DIURNAL TREND AS YDAY WITH STRONG INSOLATION/WAA PATTERN.
STRONGER SRLY BACKGROUND FLOW SHOULD PRECLUDE KBEH FM STRONG COLD
AIR DRAINAGE AS SEEN THIS AM WITH TEMPS INTO UPR 30S BY 07 UTC
THIS AM...WILL HOWEVER FAVOR A BIT COOLER THAN MOS TONIGHT. NRN
STREAM WAVE ACRS NRN ROCKIES COMBINE WITH CHIHUAHUAN DESERT/
EDWARDS PLATEAU DISTURBANCE TO AFFORD PROLONGED 7-5H HEIGHT FALL
AXIS AHEAD OF FNTL S FOR GENERAL ASCENT...DESPITE LLJ AXIS AND SFC
LOW PUSHING WELL N/NE OF CWA. FOCUS OF WX IN MONDAY NIGHT PERIOD
WITH LITTLE TIMING DIFF SEEN IN SREF/GFS/NAM. BY F42 I295 UPGLIDE
WITH AID OF 8-9 G/KG MSTR TAP SHOULD FINALLY BEGIN TO SEE SHRA 
OVERCOME INITIALLY HI CPDS GIVEN H8-H5 DRY LYR FM NW TO SE ACRS CWA
THRU MON NIGHT AND HAVE AFFORDED SOME TEMPORAL/SPATIAL RESOLUTION
TO CHC POPS. RELUCTANT AT THIS TIME TO TREND HIR THAN 50 POP NRN
CWA GIVEN LACK OF STRONG FORCED ASCENT AND SLIGHT DOWNWARD
MODIFICATION OF HPC PRECIP AMNTS.

LONG TERM...

CDFNT WILL HAVE MOVED THROUGH THE AREA BY THE START OF THE LONG TERM 
PD TUE MORNING. MODELS HAVE BEEN FAIRLY CONSISTENT SUGGESTING A BAND 
OF POST FRONTAL SHOWERS WILL AFFECT THE AREA EARLY TUE IN 
RESPONSE TO AN AMPLIFYING SHRTWV AND ACCOMPANYING MID LEVEL 
FRONTOGENESIS MOVG INTO THE GRTLKS. RUN-RUN CONTINUITY WRT LOCATION 
OF THIS BAND HAS NOT BEEN VERY GOOD, BUT 00Z MODELS ARE IN DECENT 
AGREEMENT WITH .1-.25" QPF OVER MUCH OF THE CWA WITH HIGH CHC TO LOW 
LIKELY MOS POPS... SO TRENDED OUR POPS UP FOR TUE. NAM/GFS BUFR 
SOUNDINGS SUGGESTS MOS TEMPS ARE TOO WARM TUE...STAYED CLOSE TO 
GOING FCST HIGHS IN THE L-M50S. RIDGING SFC AND ALOFT WILL BUILD 
INTO THE AREA TUE NGT IN THE WAKE TUE'S SHRTWV, PROVIDING CLEARING 
SKIES AND DIMINISHING WINDS CAUSING DECENT RADIATIONAL COOLING 
CONDITIONS TO DVLP OVERNIGHT. LITTLE CHANGE MADE TO GOING MINS IN 
L-M30S WHICH ARE A BIT BLO LATEST MEX FCSTS. 

00Z MODELS IN FAIR AGREEMENT THAT DIGGING SHRTWV WHICH MOVES THROUGH 
THE GRTLKS TUE WILL CLOSE OFF NR THE MID ATLANTIC COAST AS IT
PSBLY MERGES WITH REMNANTS OF HURRICANE IDA BY THU MORNING. THIS
WILL RESULT IN SLOW EASTWARD PROGRESSION OF RIDGE FROM THE GRTLKS
THROUGH THE ERN U.S. LATE IN THE WEEK AND LIKELY CAUSE
WKNG/DEFLECTION NEWD OF NEXT SGFNT SHRTWV TO MOVE FM THE ERN
PACIFIC ACROSS THE ROCKIES/PLAINS AND TO THE UPR GRTLKS DURING
THIS PERIOD. GFS APPEARS TO BE AN OUTLIER MAINTAINING STRENGTH OF
THIS SHRTWV AND BREAKING DOWN ERN RIDGE FASTER THAN ECMWF/GLOBAL
GEM AND GFS ENSEMBLE MEAN. ECMWF SUGGESTS IF ANY PRECIP OCCURS
WITH THIS SYSTEM IN OUR AREA LATE IN THE PD, IT WILL BE VERY
LIGHT, SO FOR NOW CONTD WITH A DRY WX FOR SATURDAY. IN THE
MEANTIME RIDGE SHOULD PROVIDE FAIR WX WITH LIGHT WINDS WED, AND
GRADUAL WARMUP THU-FRI AS RETURN FLOW ON BACKSIDE OF HIGH DVLPS
OVER THE REGION.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

SHORT TERM...MURPHY
LONG TERM...JT
AVIATION...LUD