Severe Thunderstorm Warning 55, NWS Omaha, NE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
313 PM CDT MON APR 2 2007

.DISCUSSION...
THE CHANCE FOR TSTMS AND POSSIBILITY OF SEVERE STORMS ARE THE MAIN
CONCERNS IN THE SHORT TERM. TEMPERATURES THE REST OF THE WEEK AND A
COUPLE CHANCES FOR LIGHT SNOW OR A LIGHT SNOW/RAIN MIX ARE THE
PROBLEMS FARTHER OUT.

LATEST WATER VAPOR LOOP DEPICTED SHORTWAVE TROUGH/VORT MAX MOVING
EWD FROM MT AND WY. STRONGEST UPPER TROPOSPHERIC FORCING...AS SHOWN
BY 500-300 MB QVECTORS AND DIVERGENCE...STAYS TO THE NORTH ACROSS
THE DKTS AND MN. 500 MB HEIGHT FALL CENTER IS EXPECTED TO MOVE
ACROSS SD AND THE MID LEVEL OMEGA FIELDS INDICATE DECENT UPWARD
VERTICAL MOTION MOVING THROUGH OUR AREA OVERNIGHT. THIS MAKES SENSE
WITH LIFT ON NORTH SIDE OF FRONTAL BOUNDARY. MODELS DIFFER ON THE
LOCATION OF HIGHEST QPF TONIGHT.

20Z SURFACE ANALYSIS SHOWED LOW PRESSURE IN NERN CO WITH WARM FRONT
EXTENDING EWD ALONG THE NE/KS BORDER. TEMPS SOUTH OF THE FNT WERE AT
OR ABOVE 80 F...AND MOISTURE WAS WORKING ITS WAY NORTH QUICKLY...
WITH UPPER 50S SFC DEWPTS IN SRN KS. MOISTURE LIFTING OVER FNT THIS
EVENING SHOULD BE MAIN REASON FOR CONVECTIVE INITIATION BY 02Z...
MAINLY OVER SWRN IA AND SERN NE. STORMS ALSO RACING QUICKLY EWD
FROM WRN NE AND THESE SHOULD AFFECT NRN ZONES. WENT WITH SCT TSTMS
MOST AREAS THROUGH 06Z.

WILL KEEP A MENTION OF PSBL TSTMS AFTER 06Z...BUT BEST CHANCE OF
ANY SEVERE STORMS SHOULD BE BEFORE THAT. MODELS INDICATE THAT THE
FNT SHOULD MOVE THROUGH ALL OF OUR AREA BY 12Z TUESDAY. COLD AIR
ALOFT AND MOISTURE WRAPPING AROUND 500 MB SYSTEM THAT WILL BE
INTENSIFYING OVER THE DKTS SUGGEST POTENTIAL FOR SOME LIGHT RAIN
OR SNOW SHOWERS IN OUR NORTHERN ZONES. FOR NOW...WILL JUST MENTION
THIS FOR THE MORNING HOURS...BUT SHOWERS COULD LAST LONGER. HIGHS
SHOULD BE IN THE 40S NORTH AND 50S SOUTH.

OUR AREA IS THEN IN COOL/COLD NW 500 MB FLOW INTO LATE WEEK...AS
A CLOSED LOW TRACKS ACROSS THE GREAT LAKES REGION AND RIDGE BUILDS
OVER THE ROCKIES. AT THE SURFACE...RIDGE OF HIGH PRESSURE WILL
EXTEND FROM CANADA SWD THROUGH THE PLAINS. 12Z RUNS OF THE GFS AND
NAM BOTH INDICATE SOME POTENTIAL FOR LIGHT PCPN THURSDAY...GFS
MORE SO THAN THE NAM. THIS DEFINITELY SEEMS POSSIBLE...SO ADDED LOW
POPS. GFS BRINGS ANOTHER DISTURBANCE DOWN FOR FRIDAY NIGHT...AND
THIS COULD PRODUCE SOME SNOW AS WELL. FOR NOW...WILL JUST GO WITH
A SLIGHT CHANCE IN MOST OF THE AREA. YET ANOTHER DISTURBANCE IN
THE NW FLOW COULD BRING SOME PCPN SUNDAY NIGHT...BUT DID NOT PUT
THIS IN THE GRIDS FOR NOW.

LARGE SCALE PATTERN DOES NOT CHANGE MUCH INTO THE WEEKEND...SO IT
WILL REMAIN COOL. BELIEVE GFS IS WARMING THINGS UP TOO MUCH BY
NEXT MONDAY.

&&

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

MILLER

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
1041 PM CDT MON APR 2 2007

IAZ043-055-056-069-079-080-090-091-NEZ011-012-015>018-030>034-
042>045-050>053-065>068-078-088>093-031745-
MONONA-HARRISON-SHELBY-POTTAWATTAMIE-MILLS-MONTGOMERY-FREMONT-
PAGE-KNOX-CEDAR-THURSTON-ANTELOPE-PIERCE-WAYNE-BOONE-MADISON-
STANTON-CUMING-BURT-PLATTE-COLFAX-DODGE-WASHINGTON-BUTLER-
SAUNDERS-DOUGLAS-SARPY-SEWARD-LANCASTER-CASS-OTOE-SALINE-
JEFFERSON-GAGE-JOHNSON-NEMAHA-PAWNEE-RICHARDSON-
1041 PM CDT MON APR 2 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHWEST
IOWA...WEST CENTRAL IOWA...EAST CENTRAL NEBRASKA...NORTHEAST
NEBRASKA AND SOUTHEAST NEBRASKA.

.DAY ONE...TONIGHT AND TUESDAY

A LINE OF SEVERE STORMS WILL CONTINUE TO MOVE ACROSS THE OUTLOOK
AREA INTO THE OVERNIGHT HOURS. DAMAGING WIND GUSTS OF UP TO 70 MPH WILL
BE THE PRIMARY HAZARD...HOWEVER LARGE HAIL IS ALSO POSSIBLE.

.DAYS TWO THROUGH SEVEN...TUESDAY NIGHT THROUGH MONDAY

SUB FREEZING TEMPERATURES ARE POSSIBLE EACH MORNING WEDNESDAY
THROUGH SATURDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED OVERNIGHT.

GRIFFIS