[LeArc] Forecast Discussion : MLI@ 4/29/2003 3:05:08 PM

[learc@mailman.qth.net]

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


FXUS63 KDVN 292001
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
301 PM CDT TUE APR 29 2003

THE SYNOPTIC PICTURE THIS AFTERNOON SHOWS AREA OF SHOWERS TRANSITING
THE FORECAST AREA IN ASSOCIATION WITH A STRONG VORT MAX.  TO THE
SOUTH A WARM FRONT EXTENDS FROM A SOUTHWEST KANSAS LOW ACROSS SOUTH
CENTRAL MISSOURI. TO THE NORTH A STRONG HIGH EXTENDS FROM SOUTH
CENTRAL CANADA ACROSS THE GREAT LAKES.  AT 500MB A WEAK RIDGE COVERS
MUCH OF THE CENTRAL U.S...WITH A WEAK SHORT WAVE MOVING EAST OVER
THE SOUTHERN PLAINS.  TO THE WEST...A TROF IS ALONG THE WEST
COAST...WITH A CLOSED LOW NORTH OF SFO.

THE PRIMARY FORECAST CONCERN IN THE SHORT TERM IS THE WARM FRONT
LIFTING INTO THE FORECAST AREA OVER THE NEXT 24 HOURS.  CURRENT
PRECIP WILL CLEAR TO THE EAST THIS EVENING.  TONIGHT CONVECTION WILL
FIRE AGAIN ON THE NOSE OF THE 850MB JET INTO NORTHEAST KANSAS AND
SOUTHEAST NEBRASKA...BUT MAY HAVE A HARD TIME WORKING EAST ALL THE
WAY TO DVN BY 12Z DUE TO UNFAVORABLE 700-300MB THICKNESS PATTERN.
MEANWHILE...THE WARM FRONT WILL PUSH SLOWLY NORTH TO NEAR EOK BY 12Z
WEDNESDAY.  WILL STILL KEEP IDEA OF AT LEAST SOME PRECIP LATE
TONIGHT INTO WEDNESDAY DUE TO HIGH POPS AND ONGOING FORECAST.
DEPENDING UPON LINGERING PRECIP WEDNESDAY MORNING...IF ANY...FRONT
WILL PUSH NORTH TO JUST SOUTH OF I-80 BY 00Z. AFTERNOON CAPES WILL
BE STRONG IN SOUTH CENTRAL IOWA...AND ANY CONVECTION FIRING THERE
WILL MAKE IT INTO THE DVN AREA IN THE LATE AFTERNOON OR
EVENING...WITH THE POTENTIAL FOR SEVERE.

WENDESDAY NIGHT THE POTENTIAL FOR SEVERE DEPENDS ON HOW MUCH
SUNSHINE CAN HEAT THE SURFACE...THOUGH THUNDERSTORMS LIKELY WITH
SURFACE LOW APPROACHING SOUTHERN CWA...AND GOOD INSTABILITY MODELED
TO MOVE INTO SOUTHERN THIRD OF CWA.  WILL KEEP CURRENT SEVERE
WORDING FOR NOW...THOUGH LATER SHIFTS WILL HAVE TO RE-EVALUATE.

THURSDAY IS THE DAY FOR ALL OF THIS TO SHIFT EAST...WITH THE
SURFACE LOW TO THE EAST OF THE CWA.  WITH THE 500MB TROUGH AXIS
STILL TO MOVE ACROSS THE AREA...COULD STILL GET SOME SHRA ACTIVITY...
AND HAVE HUNG ONTO CHANCE POPS THROUGH THE AFTERNOON...AND INTO THE
EVENING HOURS. THINK THAT BY MIDNIGHT ALL PRECIP OUGHT TO BE EAST
OF THE CWA.  FRIDAY LOOKS DRY...THOUGH CLOUDY AND COOL WITH UPPER
LEVEL WAVE JUST EXITING OFF TO THE EAST AND NORTH FLOW AT THE
SURFACE.

EXTENDED...SATURDAY THROUGH TUESDAY
SATURDAY AND MOST OF SUNDAY STILL QUITE QUIET...WITH SURFACE RIDGE
OVER THE AREA ON SATURDAY...AND SHIFTING TO THE EAST FOR SUNDAY.
SATURDAY WILL BE COOL...WITH THE CANADIAN RIDGE OVERHEAD...BUT THEN
WARMING SOMEWHAT FOR SUNDAY AND MONDAY IN SOUTHERLY FLOW AHEAD OF THE
NEXT SYSTEM.  SHOWERS AND THUNDERSTORMS SHOULD MOVE INTO THE AREA
SUNDAY NIGHT AND MONDAY...WITH A SURFACE LOW SYSTEM THAT MOVES ACROSS
THE CWA MONDAY NIGHT.  FOR TUESDAY...HAVE KEPT TEMPS ON THE COOL
SIDE WITH THE AREA BACK INTO NORTHEAST FLOW.

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

$$

LRE