Severe Thunderstorm Warning 281, NWS Omaha, NE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
329 AM CDT THU AUG 16 2007

.DISCUSSION...

MAIN FORECAST CHALLENGE IS TSTM CHANCES TODAY AND RESIDUAL CLOUDS
AFFECTING TEMPS.

TWO MCS COMPLEXES HEADING EAST INTO THE FORECAST AREA THIS
MORNING. NORTHERN MOST CURRENTLY AFFECTING NORTH CENTRAL NEB AND
BEGINNING TO MOVE INTO NERN NEB. THINK A FEW REMNANTS WILL REMAIN
ACROSS THE NORTH BY 15Z...BUT LLVL CONVERGENCE LACKING TO SUPPORT
ACTIVITY MUCH FURTHER SOUTH. BEST CHANCE FOR TSTMS WL BE WITH THE
SOUTHERN COMPLEX MOVING ACROSS NWRN KS/SWRN NEB. SFC BOUNDARY
GENERALLY EXTENDING ACROSS THE NEB/KS BORDER AND 35-40KT LLVL JET
NOSING INTO THE AREA SHOULD FEED SCATTERED ACTIVITY THRU MUCH
OF THE MORNING ACROSS SRN ZONES. SFC DEWPOINTS REMAIN IN THE LOW
70S WELL NORTH OF THE BOUNDARY WHICH IS CAUSING SOME REDUCTION IN
VISIBILITIES WITH SFC TEMPS IN THE 70S BUT NOT EXPECTING MUCH IN
THE WAY OF DENSE FOG THIS AM. DRIER DEWPOINTS (60S) SHOULD BEGIN
TO ADVECT INTO THE NRN COUNTIES LATER THIS MORNING/EARLY AFTERNOON
AS HI PRES MOVES ACROSS THE ERN DAKOTAS AND MN. THIS HI PRES
SYSTEM PUSHES SFC BOUNDARY INTO NRN KS/MO BY LATE IN THE DAY AND
SO SHOULD BE PCPN FREE THROUGH THE EVENING HOURS WITH VERY
PLEASANT TEMPS/DEWPOINTS. FOLLOWED MORE CLOSELY TO MET/FWC TEMP
GUIDANCE WITH MID 80S NORTH OF THE BOUNDARY AND AROUND 90 ALONG
THE KS/NEB BORDER. MAV HAS BEEN RUNNING MUCH TO WARM LATELY.

FRIDAY SHOULD BE DRY AND STRONG RETURN FLOW SETS UP BY FRIDAY
NIGHT. HAVE REDUCED POPS FRIDAY NIGHT/SATURDAY MORNING AS IT LOOKS
LIKE MAIN COMPLEX WL BE WELL TO OUR NORTHEAST WHERE LLVL CONVERGENCE
AND THETA-E ADVECTION ARE STRONGEST. MAY SEE SOME LIGHT ACTIVITY
SKIRT THE FAR NERN COUNTIES SO WL KEEP SMALL POP IN TO COVER THIS.
HAVE REDUCED POPS ON SAT AND SUN AS WELL AS SFC BOUNDARY FORECAST
TO REMAIN DRAPED NORTH OF THE AREA. STILL ANY LITTLE PERTURBATION
IN THE WESTERLIES COULD SPARK SOMETHING SO CANT RULE OUT A
CHANCE OF TSTMS THRU THE WEEKEND...BUT FEEL BRUNT OF ANY ACTIVITY WL BE
TO OUR NORTH.

OTHERWISE...NO CHANGES MADE TO GOING FORECAST WITH ACTIVE PATTERN
CONTINUING INTO NEXT WEEK.

&&

.AVIATION...

HIGH PRESSURE WILL BUILD SEWD ACROSS THE NRN PLAINS TODAY...WHICH
SHOULD FORCE HOTTEST AIR AND MAIN FRONTAL BOUNDARY FARTHER SOUTH.
SHOWERS AND THUNDERSTORMS EARLY THIS MORNING OVER NORTH CENTRAL
NEBRASKA COULD AFFECT KOFK...AND IF THEY HOLD TOGETHER AS THE TURN
SOUTHEAST THEY COULD GET INTO KOMA AND KLNK LATER. ISOLATED STORMS
NOW OVER SOUTHEASTERN NEBRASKA COULD AFFECT KLNK BEFORE 12Z. SOME
FOG WILL OCCUR...MAINLY PATCHY...BUT COULD SEE VALUES DOWN TO ABOUT
3 MILES OR SO. FAIRLY THICK MID AND HIGH LEVEL CLOUDINESS SHOULD
HELP KEEP VISIBILITY UP A LITTLE. OTHERWISE...AFTER 15Z CONDITIONS
SHOULD BE VFR...OUTSIDE OF ANY THUNDERSTORM ACTIVITY.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&

GRIFFIS/MILLER

HAZARDOUS WEATHER OUTLOOK...CORRECTION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
605 PM CDT WED AUG 15 2007

IAZ043-055-056-069-079-080-090-091-NEZ011-012-015>018-030>034-
042>045-050>053-065>068-078-088>093-161100-
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-
605 PM CDT WED AUG 15 2007

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

.DAY ONE...TONIGHT AND THURSDAY

THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS TONIGHT ACROSS THE
AREA. THE GREATEST THREAT FOR SEVERE WEATHER THIS EVENING IS SOUTH
OF A HARLAN TO FREMONT TO COLUMBUS LINE.  DAMAGING WINDS AND
LARGE HAIL WILL BE THE PRIMARY HAZARDS.

A STATIONARY FRONT EXTENDS FROM NORTH CENTRAL KANSAS INTO CENTRAL
IOWA. NORTH OF THIS FRONT...LOW LEVEL MOISTURE IS ABUNDANT.  SEVERE
THUNDERSTORMS MAY DEVELOP THIS EVENING AS AN UPPER LEVEL
DISTURBANCE MOVES ACROSS THE REGION.  MORE THUNDERSTORMS ARE
POSSIBLE ON THURSDAY AS A COLD FRONT MOVES SOUTHWARD ACROSS THE
REGION.

.DAYS TWO THROUGH SEVEN...THURSDAY NIGHT THROUGH WEDNESDAY

THUNDERSTORMS ARE POSSIBLE FRIDAY NIGHT THROUGH TUESDAY.

.SPOTTER INFORMATION STATEMENT...

STORM SPOTTER ACTIVATION MAY BE NEEDED TONIGHT ACROSS SOUTHEAST
NEBRASKA AND SOUTHWEST IOWA.

SMITH