[LeArc] Forecast Discussion : MLI@ 5/1/2003 2:48:54 PM

[learc@mailman.qth.net]

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


FXUS63 KDVN 011947
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
247 PM CDT THU MAY 1 2003

SYNOPTIC PICTURE THIS AFTERNOON SHOWS QUASI-ZONAL FLOW AT 500MB
ACROSS THE U.S...WITH A WEAK SHORT WAVE OVER NEBRASKA.  AT THE
SURFACE THE COLD FRONT IS MAKING SLOW HEADWAY INTO CENTRAL ILLINOIS.
THE MODELS INITIALIZED WELL AT 12Z THIS MORNING.

THE PRIMARY FORECAST CONCERNS OVER THE NEXT 7 DAYS ARE TWO-FOLD.
FIRST IS THE CHANCE FOR SHOWERS ASSOCIATED WITH A JET STREAK IN THE
SATURDAY NIGHT/SUNDAY TIME FRAME.  SECOND...AND OVERLAPPING THIS
POTENTIAL EVENT...IS A WARM FRONT LIFTING THROUGH THE FORECAST AREA
LIFTING THROUGH THE FORECAST AREA SUNDAY AFTERNOON OR NIGHT...WITH
THE ASSOCIATED LOW AND COLD FRONT MONDAY AFTERNOON OR EVENING.

THE SHORT-TERM MODELS AGREE ON THE SURFACE FRONT MOVING WELL AWAY
TO THE EAST TONIGHT.  LOW-LEVEL MOISTURE...WITH DRIER AIR ABOVE...
AND WEAK LIFT...WILL PROMOTE OCCASIONAL DRIZZLE TONIGHT.  A VORT MAX
MOVING THRU THE FORECAST AREA TUESDAY MORNING...COULD KEEP SOME
CHANCE OF PRECIP INTO FRIDAY MORNING.

LOOKING FURTHER AHEAD...A 100KT JET WILL LIFT OVER THE AREA FROM
THE SOUTHWEST ON SUNDAY...WITH 300MB DIVERGENCE STARTING LATE
SATURDAY NIGHT.  AT THE SAME TIME...A SURFACE LOW WILL MOVE OUT OF
THE HIGH PLAINS INTO CENTRAL KANSAS SATURDAY NIGHT...WITH A WARM
FRONT FORMING ALONG THE ARKANSAS-MISSOURI LINE. 700MB VV'S AND UPPER
DIVERGENCE WILL BE STRONG ACROSS THE FORECAST AREA SATURDAY NIGHT
AND SUNDAY.  THE WARM FRONT WILL LIFT THRU THE FORECAST AREA SUNDAY
AFTERNOON OR NIGHT.  THE MEDIUM-RANGE ARE IS DISAGREEMENT ON THE
TRACK OF THE ASSOCIATED SURFACE LOW...WITH THE MRF AND EUROPEAN
FAVORING A WARM SECTOR SOLUTION WITH THE LOW TRAVELING NORTH OF THE
AREA MONDAY...WITH THE TRAILING COLD FRONT MONDAY AFTERNOON OR
EVENING.  THE UK FAVORS A COOLER SOLUTION WITH THE LOW MOVING SOUTH
OF THE AREA.  AN ASSOCIATED 500MB LOW WILL MOVE JUST NORTH OF THE
AREA MONDAY.  WILL TEND TOWARDS MRF/EUROPEAN SOLUTION.

LITTLE SIGNIFICANT CHANGE TO ONGOING FORECAST.  FROST STILL LOOKS
POSSIBLE SATURDAY MORNING AT LEAST NORTH...MAYBE CENTRAL. WILL
PROBABLY INTRODUCE PRECIP SATURDAY NIGHT...AT LEAST SOUTHWEST.

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

$$

REA