[LeArc] Forecast Discussion : MLI@ 6/15/02 2:28:11 PM

[learc@mailman.qth.net]

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


FXUS63 KDVN 151927
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
227 PM CDT SAT JUN 15 2002

UPPER LEVEL LOW MOVING OFF TO THE EAST EVER SO SLOW.  THUS
CONTINUED NORTHWEST FLOW WITH COLD AIR ALOFT AND EMBEDDED WAVES WILL
KEEP US ON OUR TOES FOR ANOTHER DAY AND EVENING.  LATEST SURFACE
ANALYSIS AND MSAS DATA INDICATING BROAD WEST EAST TROUGH ACROSS IOWA
WITH 80S WORKING INTO SOUTHWEST IOWA. THIS COUNTERED BY 60 DEGREE AIR
SINKING INTO NORTHERN IOWA.  12Z 700 MB WAVE WITH SOME SPEED
CONVERGENCE REFLECTED BY ACTIVITY DROPPING INTO NORTH IOWA.

CHALLENGES IN THE SHORT TERM WILL ONCE AGAIN BE THE CHANCE OF SOME
LATE AFTERNOON AND EVENING THUNDERSTORMS DEVELOPING WITH THE WAVE
MOVING ACROSS OUR FORECAST AREA.  AM DVN SOUNDING INDICATES
POSSIBILITY OF MARGINAL SEVERE HAIL IF THUNDERSTORMS DO DEVELOP AND
MAYBE SOME 40 TO 50 MPH WINDS.  ADDITIONAL WAVES WILL DROP ACROSS THE
FORECAST AREA NEXT COUPLE OF DAYS CREATING A TIMING CHALLENGE.

ETA AND AVN INITIALIZED WELL AT 12Z AT 500 MB LEVEL HEIGHTS AND
PLACEMENT.  18Z ACTUALLY PICKS UP ON WAVE IN NEBRASKA. NORTHERN IOWA
WAVE BEST IDENTIFIED AT 700 MB. ETA AND MESOETA ACTUALLY DID A PRETTY
DECENT JOB ON PLACEMENT OF PRECIPITATION AT 18Z. AT LEAST THROUGH
TUESDAY BOTH WILL BE USED TO HELP DETERMINE TIMING OF PRECIPITATION
WITH NEXT COUPLE OF WAVES COMING DOWN IN THE NORTHWEST FLOW.

PREVIOUS PACKAGE APPEARS TO HAVE A GOOD HANDLE ON NEAR TERM...
THROUGH WEDNESDAY...OF UNSETTLED WEATHER THAT IS TYPICAL WITH
NORTHWEST FLOW.  FORECAST AREA SHOULD BE ON BACK SIDE OF PASSING
BOUNDARY AND UPPER DISTURBANCE TONIGHT SO LOWS WILL STAY ON THE COOL
SIDE.  ETA WAS COMING SOMEWHAT IN LINE WITH AVN AND MRF OF A
MORE ZONAL FLOW TOWARD MID PART OF FORECAST PACKAGE.  WEDNESDAY
INTO THURSDAY FLOW WILL FLATTEN OUT SOMEWHAT BUT WILL STILL MAKE
TIMING OF THE FASTER MOVING SHORTWAVES SOMEWHAT CHALLENGING THIS FAR
OUT.  SEE NO REASONS TO MAKE ANY CHANGES IN THE CURRENT PACKAGE AT
THIS TIME.

LOOKING AT THE END OF THE EXTENDED FORECAST...FRIDAY AND SATURDAY
SHOULD BE IN A RETURN SOUTHERLY FLOW WITH SEASONABLE HIGHS AND
LOWS.  PROBABLY WILL HAVE A WARM FRONTAL BOUNDARY LAY OUT JUST
NORTH OF OUR FORECAST AREA.  AS 500 MB TROUGH OUT WEST DIGS TO THE
SOUTHEAST...A BROAD UPPER RIDGE SHOULD DEVELOP OVER THE MIDWEST.
CURRENT FORECAST IS PICKING UP ON A RIDGE RIDER WHICH PROMPTED THE
CHANCE OF RAIN ON FRIDAY.  THIS COULD HAPPEN AGAIN ON SATURDAY...BUT
AT THIS TIME FEEL THE BETTER CHANCE OF PRECIPITATION WILL BE NORTH OF
OUR FORECAST AREA. NOT ENOUGH CONFIDENCE TO ADD PRECIPITATION TO
SATURDAY AT THIS TIME.

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

MEYER