[LeArc] Forecast Discussion : MLI@ 7/27/2003 3:55:25 PM

[learc@mailman.qth.net]

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


FXUS63 KDVN 272045
AFDMLI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
345 PM CDT SUN JUL 27 2003

SURFACE FRONT BISECTING CWA THIS AFTERNOON...FROM ABOUT KVYS IN N 
CENTRAL IL...TO JUST NORTH OF QUAD CITIES...THEN CURVING SOUTHWEST 
ACROSS SOUTH CENTRAL IA TO LOW IN CENTRAL KS AT 18Z. EXTENSIVE HIGH 
CLOUD COVER LINGERS OVER SOUTHERN HALF CWFA ASSOCIATED WITH FAST 
MOVING MCS THAT REALLY TOOK OFF JUST WEST OF KDVN AND CONTINUES TO 
RACE EAST ALONG I-80 ACROSS IN. AREA 88DS SHOWING SHOWERS MAINLY 
NORTH OF FRONT IN CENTRAL TO WESTERN IA. INITIAL FORECAST CHALLENGE 
IS TSRA CHANCES UNTIL FRONT SETTLES WELL TO SOUTH ON MONDAY...THEN 
MAINLY TEMPERATURE CONCERNS. 

WEAK MID LEVEL WAVES ON SOUTH EDGE OF WESTERLIES DIFFICULT TO 
DISCERN...BUT WILL BE CRITICAL TO TSRA CHANCES TONIGHT. IT APPEARS 
THAT ONE MAY BE OVER SD ASSISTING WITH WIDESPREAD SHOWERS ON 88D 
MOSAIC IN THE EASTERN SD. GFS IS ALONE WITH STRONG VORT MAX OVER 
WESTERN IA BY 00Z...WHICH LOOKS A BIT TOO FAST AND TOO STRONG...BUT 
ONLY MODEL TO CAPTURE WAVE AND WILL FOLLOW ITS GENERAL TREND. EARLY 
AFTERNOON SURFACE PRESSURE FALLS AXIS OVER CENTRAL AND WESTERN IA 
POINTING TOWARD THIS SOLUTION AS WELL. WITH SURFACE DEWPOINTS STILL 
IN LOWER 70S SOUTH OF FRONT AND LITTLE IF ANY CAP COMPARED TO PAST 
FEW DAYS...SHOULD BE ABLE TO GET MORE SURFACE BASED CONVECTION GOING 
IN UNSTABLE AIRMASS SOUTH OF FRONT AND RAISED POPS TO LIKELY FOR 
SOUTHERN TIER OF COUNTIES. WENT WITH HIGH CHANCE POPS ALONG AND JUST 
SOUTH OF FRONT. SEVERE POTENTIAL LOOKS LIMITED TO POSSIBLY SOME 
SEVERE HAIL ALONG AND NORTH OF FRONT IF A SYSTEM CAN GET ORGANIZED 
BEFORE THE FRONT...AND DEEP MOISTURE POOLING SHIFT TO SOUTH MONDAY 
MORNING. ON MONDAY...INTRODUCED SOME AFTERNOON SHOWER CHANCES AS 
MODELS INDICATE SIGNIFICANT SHORTWAVE ROTATING AROUND UPPER LOW TO 
NORTHEAST IN AFTERNOON PERIOD. 

FEW CHANGES MADE TO EXTENDED GRIDS...ESPECIALLY TO TEMPERATURE 
GRIDS. NEXT SIGNIFICANT RAIN CHANCES STILL ON WEDNESDAY WITH NEXT 
FRONTAL PASSAGE AND STRONG UPPER TROUGH DEVELOPS OVER UPPER MISS 
VALLEY. INTRODUCED POPS IN DAY 7...FOLLOWING GFS WITH SHORTWAVE IN 
NW FLOW.  

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

$$
SHEETS