[LeArc] Forecast Discussion : MLI@ 9/8/02 2:21:12 PM

[learc@mailman.qth.net]

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


FXUS63 KDVN 081926
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
225 PM CDT SUN SEP 8 2002

ANOTHER FAIR NIGHT IN STORE FOR THE AREA AS PERSISTENT AND DEEP UPPER
RIDGE CONTINUES ITS INFLUENCE OVER THE AREA. TAKING SLIGHT NIGHT-TO-
NIGHT MODERATION INTO ACCOUNT...WITH HIGHER SFC DPTS NOW IN PLACE
ACRS THE CWA...FWC/MAV BLEND LOOKS GOOD FOR OVERNIGHT LOWS WHICH
COMES UP WITH VALUES A DEGREE OR TWO HIGHER THAN WHAT OCCURRED LAST
NIGHT. EVEN WITH LIGHT SOUTHERLY SFC BREEZE...FEEL PATCHY FOG OF 1
1/2 TO 3 MILE VARIETY WILL OCCUR TOWARD DAYBREAK...BUT STILL NOT
WORTHY OF ZONE MENTION.

MONDAY SHOULD BE CHARACTERIZED BY ANOTHER ABNORMALLY WARM AND HUMID
DAY FOR MID SEPTEMBER...AS WELL AS A NOTICEABLE CU FIELD. AGAIN H9-
H85 SOUTH-SOUTHEASTERLY FLOW HOLDS THERMAL LEVELS IN THAT LAYER
STEADY OR SLIGHTLY COOL ADVECTS THROUGH 00Z TUE. THIS COMBINED WITH
MORE CU AND HIGH SFC DPTS SHOULD KEEP HIGHS AT OR JUST BELOW THIS
AFTERNOONS READINGS. UPPER 80S MAY BE A GOOD CATCH-ALL. FORECAST
SOUNDINGS AGAIN PAINT UNSTABLE PICTURE TOMORROW AFTERNOON OVER THE
AREA....AND ANY SLIGHT SFC CONVERGENCE AROUND RIDGE NOSE MAY BE
ENOUGH TO SET-OFF AIR MASS TYPE ISOLATED TO WIDELY SCATTERED
SHOWERS/THUNDERSTORMS MONDAY AFTERNOON...MUCH LIKE WHAT'S GOING ON
THIS AFTERNOON TO THE WEST OF KLSX. FEEL FAR SOUTHERN AND
SOUTHEASTERN CWA MOST AT RISK OF EXPERIENCING THIS TYPE OF
ACTIVITY....BUT CHANCE APPEARS TO "IFFY" TO ADD TO ZONES FOR NOW.

SHORT RANGE MODELS CONTINUE TREND OF SLOWING DOWN AND WASHING OUT
RIBBON OF POST-FRONTAL PRECIP WITH NEXT FROPA. WILL CONTINUE TREND OF
PREVIOUS FORECAST SHIFT AND DOWN PLAY OR MAINTAIN LOW POPS. LINGERING
CVA AND SOME ISENTROPICS SHOULD CREATE PATCHY PRECIP OVER LEADING
EDGE OF INCOMING SFC RIDGE ON TUE...BUT SCENARIO CONTINUES TO LOOK
MORE AND MORE LIKE A NON SIGNIFICANT EVENT. ALTHOUGH FEEL TUE
CHARACTERIZED BY MOSTLY CLOUDY CONDITIONS...BIT OF LAG OF MORE
VIGOROUS CAA AND EXPECTED PATCHY NATURE OF PRECIP SUGGESTS HIGHS WILL
BE MORE IN LINE WITH MID TO UPPER 70S(AROUND 80 FAR SOUTHEAST)..THEN
ONGOING LOW 70S.


.LONGER RANGE(WED-SUN)...MEDIUM RANGE MODELS GENERALLY AGREE ON GRT
LKS HIGH PROVIDING FAIR AND SEASONABLY COOL WX FOR WED AND THU. WITH
NORTHEAST FLOW AND EVENTUAL LK MI EFFECT THIS FAR INLAND...COOLER MRF
HIGHS/LOWS IN LATEST RUN LOOK MORE ON TARGET.  MEDIUM RANGE MODELS
ALSO GENERALLY AGREE ON WEAK TROUGH RIPPLING ON SOUTHERN EDGE OF
WESTERLIES...TO PULL OUT OF GRT BSN AND UP TOWARD CENTRAL PLAINS ON
FRI. STILL SOME PHASING ISSUES TO BE RESOLVED WITH THIS FEATURE AND
TROPICAL TX MOISTURE FOR POTENTIAL OVERRIDING PRECIP EVENT UP OVER
AREA ON FRI...BUT WILL LEAVE ONGOING RAIN/SHOWER CHANCE FOR NOW.
LATEST UKMET KEEP SFC HIGH FIRM OVER IA ON FRI DEFLECTING PRECIP
FURTHER SOUTH FOR DRY FRI. WITH EXPECTED CLOUD COVER ANYWAY ON FRI
AND LINGERING SFC COOL POOL...WOULD EXPECT HIGHS NOT TO MAKE IT OUT
OF THE 60S. STILL WILL KEEP NEXT SAT AS DRY AND MODERATING DAY AHEAD
OF NEXT DIGGING WAVE OVER NORTHERN ROCKIES AND PLAINS. WILL
TENTATIVELY TIME PRECIP THREAT AHEAD OF NEXT POTENTIALLY STRONG COLD
FRONT SAT NIGHT AND INTO SUN. WILL PLAY NEXT SUNDAY AS ANOTHER DAY
WHERE INCOMING CAA...LINGERING PRECIP AND CLOUD COVER KEEP HIGHS
CONFINED TO THE 60S.


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

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