[LeArc] Forecast Discussion : MLI@ 2/17/03 9:07:20 PM

[learc@mailman.qth.net]

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


FXUS63 KDVN 180315
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
905 PM CST MON FEB 17 2003

IMPRESSIVE NORTHERN STREAM SYSTEM SWINGING THROUGH UPPER MIDWEST WITH
PRESSURE FALL PATTERN SUPPORTING MODELS TAKING SYSTEM THROUGH
GREAT LAKES NEXT 24 HRS. SURFACE WARM FRONT INTO EXTREME WESTERN IA ATTIM.
VARIOUS MECHANISMS PRODUCING LOTS OF CLOUD COVER ACROSS REGION THIS EVE.
PESKY STRATUS...WHICH DEVELOPED OVERNIGHT AND EARLY THIS MORNING IN
WRAPAROUND FROM LARGE EASTERN US WINTER STORM...ENHANCED 
BY LLVL MOIST FLOW FROM LAKE MI...SLOWLY SHIFTING EAST WITH TIME AS LLVL
WINDS INCREASE. LOCALIZED DENSE FOG AROUND DBQ EXPECTED TO 
LIFT NEXT FEW HOURS AS THE WINDS INCREASE. FEW FLURRIES AND VERY LIGHT SNOW
GRAINS ALSO OBSERVED HERE AT OFFICE A SHORT WHILE AGO.
NARROW BAND OF MID LEVEL CLOUDINESS MOVING THROUGH IN ASSOCIATION WITH
WARM ADVECTION WING. RADARS PICKING CLOUDS UP WITH FINE LINE OF 10-20 DBZ
BUT NOTHING REACHING GROUND WITH COPIOUS AMOUNTS OF DRY AIR IN
MID LEVELS PER 00Z UA SOUNDING. NEXT BATCH OF CLOUDINESS QUICKLY APPROACHING
FROM CENTRAL IA IN ASSOCIATION WITH FAIRLY VIGOROUS SHORTWAVE. 
STRONG SUBSIDENCE ON BACKSIDE WITH CLEARING INTO FAR WESTERN IA AND EASTERN
NE...SO PARTIAL CLEARING LOOKS REASONABLE LATER TONIGHT.
TEMPS TRICKY. NOT A LOT OF LLVL THERMAL ADVECTION. WINDS TO SHIFT TO THE
SOUTHWEST LATE TONIGHT AS WARM FRONT APPROACHES...AND COULD SEE
TEMPS JUMP UP AT THAT TIME. TEMPS HAVE DROPPED A BIT IN WESTERN ZONES WHERE
STRATUS HAS EXITED. HOWEVER...NEXT ROUND OF CLOUDS WILL MOVE IN
SOON AND EXPECT TEMPS TO RISE A BIT. OVERALL...DON/T THINK WE/LL SEE A LOT
OF DROP OVERNIGHT. CURRENT FORECAST HAS THIS HANDLED WELL AND PLAN ON 
ONLY FEW TWEAKS.  
  
UPPER FLOW TO FLATTEN IN WAKE OF VIGOROUS NORTHERN STREAM SYSTEM WITH ZONAL 
FLOW BRINGING IN MILDER PAC AIRMASS...SO MODERATING TEMPS NEXT FEW DAYS 
LOOKS GOOD. SEEMS AS THOUGH MODELS TRENDING FURTHER SOUTH WITH LATE WEEK SYSTEM
PER 12Z RUNS OF UKMET AND ECMWF AND 18Z GFS. WILL BE WATCHING CLOSELY THOUGH 
WITH PHASING ISSUES CAUSING MODELS FITS!!


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

$$

M^2