Severe Thunderstorm Warning 24, NWS Omaha, NE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
155 PM CDT WED MAY 17 2000

SEVERE WEATHER THE NEXT 10 HOURS OR SO IS THE PRIMARY FCST CONCERN.
SFC ANLYS EARLY THIS AFTN SHOWED A STRONG LOW PRES CENTER OVER NERN
CO AND THIS SHOULD MOVE ENE THROUGH TNGT.  THE TWO FNTS IN THE ERN
NE AND WRN IA AREA ARE EXPECTED TO BE IMPORTANT FOR STORM STRUCTURE
AND ORGANIZATION.  JET MAX IN EXCESS OF 110 KTS AROUND 300 MB SHOULD
MOVE OUT ACROSS KS...PUTTING OUR AREA IN THE LEFT EXIT REGION OF THE
JET MAX WITH STRONG DIVERGENCE ALOFT.  HAIL...WIND AND ISOLATED
TORNADOES ALL POSSIBLE.  RED BOX WIBIS SHORTLY TO OUR W.

BEST CHANCE OF WIDESPREAD SIGNIFICANT RAIN APPEARS TO BE OVER NERN
NE...BUT MAY SAG FARTHER TO THE S WITH THE NRN FNT.  DRY SLOT
PUNCHES INTO SERN NE...SO HEAVY RAIN SHOULD NOT BE A PROBLEM THERE.

SFC LOW SHOULD MOVE INTO SERN NE BY 12Z...AND DRY SLOT MAY SHUT DOWN
PCPN FOR A WHILE THU MORNING.  PCPN EXPECTED TO SPREAD SEWD OVER THE
AREA AGAIN DURING THE DAY AS THE FNT MOVES S.  EXPECT LITTLE IF ANY
RECOVERY OF TEMPS ACROSS NERN NE ON THU WITH CLOUDS AND PCPN...SO
TEMPS MAY STAY IN THE MID 50S TO AROUND 60.  SERN NE AND SWRN IA
ZONES AHEAD OF FNT COULD REACH THE UPPER 60S TO LOWER 70S.  HAVE
KEPT SOME CHANCE OF PCPN THU EVENING ACROSS SERN PART OF FCST AREA
BUT CLOUDS THU NGT WITH COOL TEMPS.  WILL MENTION SOME UPPER 30S IN
NRN PART OF NERN NE.  DRY CONDS WITH LESS WIND ON FRI.  MODELS ARE
FAIRLY CLOSE WITH THE LATER PERIODS...SO WILL NOT MAKE ANY MAJOR
DEVIATIONS FROM MOS.  FIRST DRAFT OF THE WORK ZONES WAS SENT.

.OMA...NONE
MILLER

IAZ043-055-056-069-079-080-090-091-NEZ011-012-015>018-030>034-
042>045-050>053-065>068-078-088>093-181200-

SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
1150 AM CDT WED MAY 17 2000

...SEVERE WEATHER OUTLOOK FOR EASTERN NEBRASKA AND SOUTHWEST IOWA...

STORM SPOTTERS GROUPS SHOULD BE ALERT AND READY FOR ACTIVATION THIS
AFTERNOON AND EVENING.

THERE IS A MODERATE RISK OF SEVERE WEATHER ACROSS A LARGE PART OF
EASTERN NEBRASKA AND SOUTHWEST IOWA.  AN AREA OF LOW PRESSURE
CENTERED OVER NORTHEAST COLORADO IS EXPECTED TO MOVE TOWARD SOUTH
CENTRAL NEBRASKA BY MIDNIGHT.  A WARM FRONT EXTENDED FROM THE  LOW
INTO SOUTHEAST NEBRASKA AND NORTHWEST MISSOURI...AND THIS SHOULD
LIFT NORTH.  IN ADDITION...A NEARLY STATIONARY FRONT STRETCHED
FROM NORTHERN COLORADO INTO NORTHEAST NEBRASKA AND NORTHWEST IOWA.
BOTH OF THESE FRONTS ARE EXPECTED TO BE IMPORTANT IN THE DEVELOPMENT
AND ORGANIZATION OF THUNDERSTORMS THROUGH THIS EVENING.

TIMING ON THE INITIAL DEVELOPMENT OF SEVERE STORMS IS NOT CLEAR.
THE MOST LIKELY TIMES THAT SEVERE STORMS WILL OCCUR TODAY IS FROM
2 PM TO 10 PM...BUT SEVERE WEATHER COULD CONTINUE AFTER MIDNIGHT.
THE AMOUNT OF SHEAR AND INSTABILITY INDICATE THAT SUPERCELL STORMS
ARE POSSIBLE.  HAIL AND DAMAGING OUTFLOW WINDS ARE THE TWO MAIN
THREATS...BUT SOME TORNADOES WILL BE POSSIBLE IN THE VICINITY OF
ANY FRONTS AND OUTFLOW BOUNDARIES.

MILLER