Tornado Warning 77, NWS Omaha, NE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
230 PM CDT THU JUL 15 2004

.DISCUSSION...
WHERE TO PLACE GREATEST CHANCE FOR PRECIPITATION...TIMING AND
TEMPERATURES THE PRIMARY CONCERNS FOR THIS FORECAST.

ISOLATED SEVERE STORMS TRACKED FROM SOUTH DAKOTA INTO PARTS OF
EASTERN NEBRASKA...WITH LATEST STRONG REFLECTIVITY FROM AROUND
MILLARD TO HAMBURG IA.  STORMS WEAKENED FROM PRODUCING GOLFBALL
SIZED HAIL IN KNOX COUNTY TO A FEW SHOWERS AT IT APPROACHED
MADISON.  STORMS TODAY HAVE BEEN IN AREA OF GREATEST THETA-E
ADVECTION AND RH WITH WEAK SHORTWAVE TROF.

THE LATEST SURFACE MAP HAD LOW PRESSURE CENTERED NEAR PIERRE
SD...WITH HIGH PRES OVR NRN MO.  SFC WNDS WERE FROM THE SOUTHEAST
AND DEWPOINTS WERE IN THE UPPER 60S FOR MUCH OF ERN NEB AND WRN
IA...WITH LOWER 70S DEWPOINTS STREAMING NWD.  WHERE IT WAS
RAINING...TEMPERATURES DROPPED INTO THE 70S...WITH 80S ELSEWHERE.

LOOK FOR CONVECTIVE COMPLEX TO CONTINUE TO DROP SE INTO MO.  OTHER
CU/AC/STORMS BEGINNING TO GET TOUCHED OFF WITH HEATING THIS
AFTERNOON OVER SD AND TO A GREATER DEGREE ACROSS NRN MN. LOOKING AT
MESOSCALE...WNDSHFT LOCATED E OF VTN AND W OF ONL.  GOOD CONVERGENCE
IN THIS AREA...WITH DEWPOINT DISCONTINUITY OF UPR 50S TO AROUND 60
AT VTN AND UPR 60S TO LOWER 70S FARTHER E. TEMPERATURES HEATING UP
AT VTN WITH MID 90S.  OUTFLOW NOTED ON VISIBLE STLT W OF ONL TO NEAR
YORK.  LAPS CAPE ABOVE 4000 J/KG THIS AREA WITH LITTLE CIN.  SPC
JUST ISSUED SWO FOR POTENTIAL TORNADO WATCH.

SHORT TERM MODELS VARY ON SCENARIO FOR TONIGHT.  THE RUC LOOKS TO BE
FOLLOWING ANOTHER WAVE OVER SD INTO NRN NEB THIS EVENING.  THE ETA
ALSO HAS A WAVE IN NW FLOW MOVING INTO NE NEB AND NW IA THIS
EVENING...WITH A STRONGER SHORTWAVE TROF OVR MN...WHICH WILL AFFECT
THE FORECAST AREA LATER TONIGHT...AND STORMS THAT FIRE OVER THE WRN
PLNS...THAT DO NOT MAKE IT FAR ENOUGH E.  THE GFS IS SIMILAR TO THE
ETA THIS EVENING IN HIGHLIGHTING THESE THREE AREAS TO FOCUS
CONVECTION...HOWEVER...A BIT MORE AGRESSIVE.  MAY BE OTHERS DUE TO
OUTFLOW BOUNDARIES THOUGH. BEST FRONTOGENESIS OVR THE WRN PLNS THIS
EVENING...EXPANDING INTO FCST AREA OVERNIGHT AND EARLY FRIDAY.

WILL MENTION OF SCT TSRA N EARLY THIS EVENING AND CHC POPS FARTHER
SOUTH LATER TONIGHT AND EARLY FRI MORNING.  SOME STORMS MAY BE
SEVERE DUE TO INSTABILITY AND DEEP LAYER SHEAR...WITH LARGE HAIL AND
DAMAGING WINDS POSSIBLE.  THESE STORMS HAVE BEEN MOVING QUICKLY
IN NW FLOW.  HIGH PWS MAY RESULT IN LOCALIZED HEAVY RAINS...BUT IS
NOT EXPECTED TO POSE A PROBLEM ON A MORE WIDESPREAD BASIS.  STORMS
THAT FORM OVR THE WESTERN PLAINS WILL TRACK SE ALONG THE TROF.
STRONG LOW LEVEL JET LOOKS TO TAKE HEAVIER RAINFALL TO THE WEST OF
THE FCST AREA.  WILL INCLUDE SOME MENTION EARLY FRI...WHITH STRONGER
N WINDS AND HIGH PRES BUILDING IN DURING THE AFTERNOON ACRS THE N.
DID NOT MAKE ANY SIGNIFICANT CHANGES SAT AND SUN.  NEW GFS IS
PERSISTENT WITH CHC PRECIP MON AFT AND RETURN MOISTURE MONDAY
NIGHT.  WITH MID LEVEL RIDGE BUILDING IN TUES...MAY BE CAPPED AND
THIS COULD KEEP BULK OF PRECIP TO THE N.  LEFT CHC FOR PRECIPITATION
IN WED AND THU AFT MID LEVEL RIDGE BREAKS DOWN AND SFC FRONT MOVE
INTO KS AND MO FRM THE NRN PLNS.  TEMPERATURES MAINLY MID 80S TO
LOWER 90S FOR HIGHS.

&&

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

&&

ZAPOTOCNY

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
500 PM CDT THU JUL 15 2004

NEZ011-012-016>018-030>033-042>044-050-051-065-066-161000-
ANTELOPE-BOONE-BUTLER-CEDAR-COLFAX-CUMING-DODGE-KNOX-LANCASTER-
MADISON-PIERCE-PLATTE-SAUNDERS-SEWARD-STANTON-WAYNE-
500 PM CDT THU JUL 15 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PARTS OF EASTERN NEBRASKA.

.DAY ONE...TONIGHT AND FRIDAY

SEVERE THUNDERSTORMS ARE EXPECTED THIS EVENING WITH LARGE HAIL...
DAMAGING WINDS AND ISOLATED TORNADOES POSSIBLE. LOCALLY HEAVY RAIN
MAY ALSO FALL IN SOME AREAS. THUNDERSTORMS MAY LINGER INTO FRIDAY
MORNING.

A SERIES OF DISTURBANCES IN NORTHWEST FLOW WILL AFFECT THE AREA.
STRONG DEEP LAYER SHEAR IS FORECAST FROM EASTERN NEBRASKA INTO
WESTERN IOWA...MEANWHILE DESTABILIZATION IS EXPECTED TO INCREASE
DURING THE EVENING AS A COLD FRONT PUSHES INTO THE AREA.

.DAYS TWO THROUGH SEVEN...FRIDAY NIGHT THROUGH THURSDAY

THERE IS A CHANCE OF MORE THUNDERSTORMS MONDAY NIGHT THROUGH
WEDNESDAY.  SOME OF THESE STORMS MAY BE SEVERE.

.SPOTTER INFORMATION STATEMENT...

STORM SPOTTER ACTIVATION IS LIKELY THIS EVENING AND MAY BE
REQUIRED LATER TONIGHT.

IAZ043-055-056-069-079-080-090-091-NEZ015-034-045-052-053-067-068-
078-088>093-161000-
BURT-CASS-DOUGLAS-FREMONT IA-GAGE-HARRISON IA-JEFFERSON-JOHNSON-
MILLS IA-MONONA IA-MONTGOMERY IA-NEMAHA-OTOE-PAGE IA-PAWNEE-
POTTAWATTAMIE IA-RICHARDSON-SALINE-SARPY-SHELBY IA-THURSTON-
WASHINGTON-
500 PM CDT THU JUL 15 2004

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

.DAY ONE...TONIGHT AND FRIDAY

SEVERE THUNDERSTORMS WILL BE POSSIBLE ACROSS THE AREA TONIGHT.
LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY HAZARDS.  LOCALLY
HEAVY RAINFALL WILL ALSO BE POSSIBLE. THUNDERSTORMS ARE EXPECTED TO
LINGER INTO FRIDAY MORNING.

A SERIES OF DISTURBANCES IN NORTHWEST FLOW WILL AFFECT THE AREA.
STRONG DEEP LAYER SHEAR IS FORECAST FROM EASTERN NEBRASKA INTO
WESTERN IOWA...WITH DESTABILIZATION EXPECTED TO INCREASE INTO
THE EVENING HOURS.

.DAYS TWO THROUGH SEVEN...FRIDAY NIGHT THROUGH THURSDAY

THERE IS A CHANCE OF MORE THUNDERSTORMS MONDAY NIGHT THROUGH
WEDNESDAY.  SOME OF THESE STORMS MAY BE SEVERE.

.SPOTTER INFORMATION STATEMENT...

STORM SPOTTER ACTIVATION MAY BE REQUIRED LATER TONIGHT.

FOBERT

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE OMAHA NE
617 PM CDT THU JUL 15 2004

..TIME...   ...EVENT...     ...CITY LOCATION...      ...LAT.LON...
..DATE...   ....MAG....     ..COUNTY LOCATION...ST.. ...SOURCE....
            ..REMARKS..

0610 PM     FUNNEL CLOUD     VERDEL                  42.81N 98.19W
07/15/2004                   KNOX               NE   BROADCAST MEDIA

&&

TFL