Hail in Iowa, July 7, 2003

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
400 PM CDT SUN JUL 6 2003

SAME OLD SAME OLD. PATTERN REMAINS STUCK FOR THE NEXT COUPLE DAYS.
THOUGH THERE IS SOUTHWARD MOVEMENT OF THE MAIN FRONTAL SYSTEM BY
LATE TONIGHT...CWA WILL REMAIN IN LOW LEVEL CONVERGENCE ZONE/S DUE
TO FRONTAL AND OR OUTFLOW BOUNDARIES. MAIN DIFFICULTIES CONTINUE TO
BE EXACTLY WHERE CONVECTION WILL FIRE AS EACH CONVECTIVE SYSTEM
MODIFIES ENVIRONMENT AND CHANGES PLACEMENT OF NEXT CONVECTIVE
DEVELOPMENT. OVERALL ONCE AGAIN MADE ONLY MINOR CHANGES TO UPCOMING
FORECAST AND BEYOND 24 HOURS BROADBRUSHED PCPN CHANCES DUE TO
UNCERTAINTIES OF BOUNDARY PLACEMENT.

IN THE SHORT TERM...CWA IS ONCE AGAIN HOME TO A FAIRLY SIGNIFICANT
OUTFLOW BOUNDARY WHICH SHOWS NICELY ON SAT PICS...SFC OBS...AND
RADAR. ADDITIONAL SECONDARY BOUNDARY JUST SW OF KMCW. MAIN QUESTION
IS WHETHER OR NOT THESE BOUNDARIES WILL LIGHT UP EARLY THIS EVENING.
LAPS AND SPC MESO DATA INDICATE AREA ALONG AND JUST TO THE SOUTH OF
THE MAIN BOUNDARY ARE NOT CAPPED WITH NEAR 3K OF CAPE. AREA JUST
NORTH OF BOUNDARY STILL WEAKLY CAPPED. NARROW ZONE OF SLIGHTLY
ENHANCES CU RIGHT ALONG BOUNDARY HAS WEAKEN OVER THE LAST COUPLE
HOURS THOUGH LOW LEVEL CONVERGENCE REMAINS FAIRLY STRONG. HAVE
INCLUDED EVENING POPS ALONG AND NORTH OF BOUNDARY. CONVECTION SHOULD
THEN DEVELOP OVER AREAS TO OUR NORTH AND MOVE SE ALONG THESE LOW
LEVEL BOUNDARIES WHICH WILL ALSO BE WERE H850 THETA-E CONVERGENCE
WILL BE LOCATED AND EDGE OF BEST H7 BAROCLINIC ZONE. BEST CHANCE FOR
PCPN OVER MCW AND ALO ZONES WITH DECREASING CHANCES FURTHER SW.

IN LATER PERIODS HAVE BECOME LESS SPECIFIC WITH DEFINITION OF POPS
AS FRONTAL POSITION WILL BE DIFFICULT. HAVE GENERALLY SHIFTED BEST
POPS AND HIGHER QPF FURTHER SOUTH INTO TUES. SHORT WAVES MOVING OVER
THE AREA WEDS WILL ALLOW THE FRONT TO LINGER CLOSE TO THE AREA
BEFORE BEING DISPLACED FURTHER S THURS AND FRIDAY.

.DSM...NONE

JAW