[LeArc] Forecast Discussion : MLI@ 6/25/02 2:47:58 AM

Tue, 25 Jun 2002 02:47:58 -0500

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

FXUS63 KDVN 250749
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
249 AM CDT TUE JUN 25 2002

UPPER AIR PATTERN TRANSITIONS TO NW FLOW OVER CENTRAL U.S. IN
RESPONSE TO S/W ENERGY MOVING ACROSS SRN CANADA AND RIDGE BUILDING OVER
ROCKIES. TO THE SOUTH...H5 LOW OVER LOWER MISSISSIPPI VALLEY MOVES
SLOWLY WEST INTO ERN TX BY THURSDAY MORNING.  AS FLOW OVER
NWRN U.S. BUCKLES...BOUNDARY FROM PLAINS INTO NORTHERN GREAT LAKES IS
FORCED SOUTH...MOVING THROUGH CWA WEDNESDAY.

MAIN CONCERN THIS MORNING WILL BE TSRA THREAT ASSOCIATED WITH THE
APPROACHING FRONT...AND ALSO WITH THE UPPER LOW TO OUR SOUTH.  FOR THE
MOST PART BELIEVE TODAY WILL BE DRY WITH FRONT REMAINING WELL TO OUR
NORTHWEST...FROM NERN NE THROUGH NERN MN.  WITH WEAK WIND FLOW THROUGH
THE DEPTH OF THE ATMOSPHERE AND MID LEVEL THERMAL RIDGE AHEAD OF FRONT
SHOULD KEEP CONVECTION CLOSE TO THE BOUNDARY THROUGH THIS AFTERNOON.
THERE WILL BE A THEAT OF SOME ISOLD TSRA OVER SERN CWA ASSOCIATED WITH
LOWER MS VALLEY H5 LOW.  CONVECTION REACHED AS FAR NORTH A CENTRAL IL
ON MONDAY.  MODELS SHOW MID LEVEL TEMPS COOLING A FEW DEGREES...ALONG
WITH INCREASING SURFACE DEWPOINTS.  LOBES OF ENERGY ROTATING AROUND
UPPER LOW MAY BE ENOUGH TO TRIGGER A FEW THUNDERTORMS THIS AFTERNOON.
DUE TO THE WEAK WIND FLOW AND PWS AROUND 1.5 INCHES...ANY TSRA THAT
DEVELOPS WILL MOVE LITTLE AND WILL HAVE THE POTENTIAL OF PRODUCING SOME
SIGNIFACANT RAINFALL.  MAIN THUNDERSTORM THREAT FOR CWA WILL BE TONIGHT
INTO WEDNESDAY AS SURFACE FRONT PUSHES SOUTHEAST.  WILL CONTINUE WITH
POPS IN THE CHANCE CATEGORY SINCE THE FRONT WILL BE MOVING THROUGH NRN
CWA DURING MORNING HOURS.  AS THE FRONT MOVES THROUGH SRN CWA WEDNESDAY
AFTERNOON...FLOW AHEAD OF FRONT BECOMES SWLY...DIMINISHING SURFACE
CONVERGENCE ALONG BOUNDARY...AND BEST UPPER LEVEL FORCING STAYS TO THE
NE.

SHOULD SEE SOME RELIEF FROM THE WARM AND HUMID CONDTIONS THURSDAY WITH
DEWPOINTS FALLING BACK INTO THE MID TO UPPER 50S. WARM WEATHER WILL
RETURN FOR THE WEEKEND AS UPPER RIDGE SHIFTS EAST INTO THE CENTRAL U.S.

MAV TEMPS LOOK THE MOST REASONABLE THROUGH THE PERIOD.

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

DLF