Hail in Iowa, August 20, 2005

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
230 PM CDT SAT AUG 20 2005

.DISCUSSION...

MAIN FORECAST CONCERNS WILL DEAL WITH TEMPERATURES IN THE SHORT TERM
THEN TIMING OF SURFACE HIGH AS IT MOVES EAST AND RETURN FLOW BACK
INTO THE NORTHERN PLAINS IN ADVANCE OF NEXT SYSTEM MID TO LATE WEEK
IN THE EXTENDED.

RATHER WEAK SURFACE PATTERN IN PLACE ACROSS THE REGION AT 18Z WITH
SECONDARY COLD FRONT STRETCHING FROM NORTHWEST WISCONSIN TO NEAR
NEBRASKA SOUTH DAKOTA BORDER. CLOSED UPPER LOW NORTH OF LAKE
SUPERIOR TRACKING QUICKLY EAST. LOWER LEVELS REMAIN RATHER MOIST
ACROSS MOST OF THE FORECAST AREA WITH DEW POINTS IN THE MID AND
UPPER 60S...BUT DRIER AIR FINALLY BEGINNING TO SPREAD INTO
NORTHWEST CORNER OF THE AREA WHERE DEW POINTS WERE IN THE 50S AT
18Z. EXPECT THIS DRIER AIR TO GRADUALLY SPREAD ACROSS THE AREA
TONIGHT INTO SUNDAY AS HIGH PRESSURE BUILDS TOWARD THE GREAT LAKES
REGION THROUGH MONDAY. EXTENSIVE CU FIELD HAS DEVELOPED ACROSS
CENTRAL PARTS OF THE AREA EARLY THIS AFTERNOON BETWEEN OFK AND OMA
AND FORECAST SOUNDINGS INDICATE SOME POTENTIAL FOR CONVECTION YET
LATE AFTERNOON INTO EARLY EVENING SO HAVE CONTINUED SLIGHT POPS FOR
EARLY EVENING PERIOD. LIGHT WINDS AND CLEAR SKIES EXPECTED ACROSS
MOST OF THE AREA AFTER SUNSET WITH SOME PATCHY FOG POSSIBLE ACROSS
THE NORTHERN HALF LATE TONIGHT AND EARLY SUNDAY MORNING.

EXTENDED...OVERALL MODELS PRETTY SIMILAR WITH TIMING OF NEXT UPPER
SYSTEM COMING INTO THE NORTHWEST CONUS EARLY NEXT WEEK WITH RETURN
FLOW DEVELOPING ACROSS THE PLAINS TUESDAY INTO WEDNESDAY IN ADVANCE
OF DEVELOPING SURFACE SYSTEM. SOME DIFFERENCES BETWEEN THE GFS AND
ECMWF HOWEVER BY MID TO LATE WEEK WITH GFS MAINTAINING A CLOSED
CIRCULATION OVER SOUTHERN CANADA THROUGH THE EXTENDED PERIOD AND
ALSO SLOWER IN MOVING THE SYSTEM OUT ACROSS THE NORTHERN PLAINS
DURING THIS TIME. ONLY MINOR CHANGES TO EXTENDED PORTION OF THE
FORECAST AT THIS TIME WITH TREND TOWARD HPC GUIDANCE. LOW POPS
CONTINUED IN THE WED TO FRI PERIOD.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...

NE...NONE.
IA...NONE.

&&

FOBERT

HAZARDOUS WEATHER OUTLOOK ... CORRECTED TO ADD FOG TONIGHT
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
1152 AM CDT SAT AUG 20 2005

IAZ043-055-056-069-079-080-090-091-NEZ011-012-015>018-030>034-
042>045-050>053-065>068-078-088>093-202300-
ANTELOPE-BOONE-BURT-BUTLER-CASS-CEDAR-COLFAX-CUMING-DODGE-DOUGLAS-
FREMONT IA-GAGE-HARRISON IA-JEFFERSON-JOHNSON-KNOX-LANCASTER-MADISON-
MILLS IA-MONONA IA-MONTGOMERY IA-NEMAHA-OTOE-PAGE IA-PAWNEE-PIERCE-
PLATTE-POTTAWATTAMIE IA-RICHARDSON-SALINE-SARPY-SAUNDERS-SEWARD-
SHELBY IA-STANTON-THURSTON-WASHINGTON-WAYNE-
1152 AM CDT SAT AUG 20 2005

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EASTERN NEBRASKA AND SOUTHWEST
IOWA.

.DAY ONE...THIS AFTERNOON AND TONIGHT

WIDELY SCATTERED THUNDERSTORMS WILL BE POSSIBLE ACROSS NORTHEAST
NEBRASKA AND WEST CENTRAL IOWA THIS AFTERNOON...MAINLY NORTH OF A
LINE FROM DAVID CITY NEBRASKA TO OAKLAND IOWA. THE SLIGHT CHANCE FOR
THUNDERSTORMS WILL SPREAD TO THE REMAINDER OF SOUTHEAST NEBRASKA AND
SOUTHWEST IOWA THIS EVENING. SOME SOME OF THE STORMS COULD PRODUCE
SMALL HAIL AND GUSTY WINDS. ANY STORMS SHOULD END BY MIDNIGHT.

PATCHY DENSE FOG MAY DEVELOP IN LOW LYING AREAS TOWARD MORNING.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THE NEXT CHANCE OF THUNDERSTORMS WILL BE WEDNESDAY THROUGH FRIDAY AS
ANOTHER COLD FRONT BEGINS TO MOVE INTO THE REGION.

.SPOTTER INFORMATION STATEMENT...

STORM SPOTTER ACTIVATION SHOULD NOT BE NEEDED THIS AFTERNOON OR
TONIGHT.

POLLACK