[LeArc] Forecast Discussion : MLI@ 4/10/2003 2:31:11 AM

[learc@mailman.qth.net]

The following weather message is provided by McDonough County E.S.D.A.


FXUS63 KDVN 100728
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
225 AM CDT THU APR 10 2003

BENIGN WX PATTERN CONTINUES WITH SURFACE RIDGE AXIS OVERHEAD AT 06Z
TO SHIFT SLOWLY S/E NEXT 24 HRS. UPPER LEVEL RIDGE IN PLAINS
TO BUILD IN LATE IN THE WEEKEND...WITH STRONG WARMING TO BEGIN NEXT 
WEEK. ONLY FLY IN OINTMENT BETWEEN NOW AND THEN COULD BE 
LLVL N/E WINDS WITH POTENTIAL FOR CLOUDS AND ENHANCED COOLING FROM
LAKE MI FRI NIGHT-SAT.

SURFACE RIDGE AXIS TO SHIFT SLOWLY S/E WITH LLVL FLOW BECOMING LIGHT
S/SW AHEAD OF FRONTAL ZONE PROGGED TO MOVE THROUGH FRI-FRI EVE.
NOT MUCH SNOW COVER LEFT IN THE NORTH...AND WHAT IS LEFT WILL BE GONE
TODAY. SNOWMELT HAS CONTRIBUTED TO MOISTENING BL BUT IT IS 
SHALLOW...THUS IF ANY FOG MORE LIKE PATCHY GROUND FOG IN 
RIVER VALLEYS OR OTHER LOW LYING AREAS NORTH. METAR/AWOS VISIBILITIES
AT 06Z 10+ MILES IN CWA WITH TEMP/DEWPT SPREADS QUITE LARGE 
(GENERALLY 7-14 DEGS). AS FOR MAXES TODAY...NGM LOOKS TOO COOL WHICH 
IS LIKELY DUE TO ADVERSE IMPACT FROM SNOW FIELD ON 
LOWER TROPOSPHERIC TEMPS...WHILE ETA TOO WARM. MIDDLE OF THE ROAD 
AVN VERIFIED BEST YESTERDAY AND SEE NO REASON TO DEVIATE FROM 
AGAIN TODAY WITH SIMILAR CONDITIONS WITH MIXING AGAIN LIMITED TO 
AROUND 900 MB. 
 
MODELS REMAIN CONSISTENT IN BRINGING FRONTAL ZONE THROUGH FRI-FRI EVE
WITH SOME TIMING DIFFERENCES. PRE-FRONTAL COMPRESSION
NOT IMPRESSIVE BUT JUST ENOUGH TO PUSH TEMPS WARMER THAN TODAY IN THE
SOUTH...WHILE DEEP POST FRONTAL MIXING TO TAP INTO WARM WEDGE
ALOFT RESULTING IN WARMER READINGS CENTRAL AND NORTH DESPITE WINDS 
BECOMING NORTHERLY.

SURFACE HIGH BUILDS INTO THE GREAT LAKES FRI NIGHT-SAT WITH LLVL FLOW
BECOMING N/E. CONCERNS WITH POTENTIAL FOR CLOUDS AND ENHANCED 
COOLING FROM LAKE MI. ATTIM FLOW FRI NIGHT PROGGED TO BE 10 KTS 
OR LESS...WHICH WOULD INDICATE MINIMAL IMPACTS EXCEPT POSSIBLY NORTHWEST
IL ZONES. RELATIVELY LIGHT FLOW WOULD SEEM TO NOT BE FAVORABLE 
FOR UNDERCUTTING GUIDANCE...THOUGH TOOK A BLEND WITH EMPHASIS TOWARD
COOLER END. ON SAT...E/NE FETCH LOOKS A BIT STRONGER (10-15 KTS)
THUS FEEL WE/LL SEE MORE OF AN IMPACT SO TRIMMED BACK MAXES A SKOOSH.
 
EXTENDED (SUN-WED)...
FRONT RETURNS NORTH ON SUN. LIMITED MOISTURE AND FORCING SO DRY FORECAST
LOOKS REASONABLE. MAIN QUESTION WILL BE WITH TIMING OF NEXT FRONT.
UPPER FLOW SOUTHWEST WITH FRONT NEARLY PARALLEL...THUS IT
WILL BE A SLOW MOVER. SLOWER MOVEMENT WOULD PUSH BACK PCPN POTENTIAL 
TIL TUE-WED...AND WOULD SUGGEST TUE BEING WARMEST AND QUITE A BIT
WARMER THAN CURRENT FORECAST WITH L/M 80S CERTAINLY NOT OUT OF QUESTION.
WON/T MAKE ANY CHANGES ATTIM BUT WILL PASS CONCERNS ON TO THE 
DAY SHIFT. 

.DVN...
IA...NONE.
IL...NONE.
MO...NONE.

$$

05