Severe Thunderstorm Warning 66, NWS North Platte, NE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
214 PM CDT THU JUN 3 1999

...FORECAST CHALLENGE...WHERE CONVECTION MAY FIRE...

...SYNOPSIS...
    SATELLITE 11-3.9 INDICATED SMALL CIRCULATION THIS AM OVER EAST
CENTRAL CO...ASSOCIATED WITH STRATUS FROM SOUTHWEST NEB TO EASTERN CO
AND WESTERN KS WHICH HAS SINCE DISSIPATED/SHIFTED EAST. LOW OVER
SOUTHWEST CONUS CONTINUES TO SEND BITS OF ENERGY NORTHEAST INTO AREA
THROUGH PERIOD. CU DEVELOPING AS WE SPEAK IN GARDEN COUNTY (EASTERN
PANHANDLE REGION.) WV IMAGERY SHOWS S/W ROUNDING THE BASE OF THE TROF
LOOKING TO SET OFF CONVECTION TNT.

...MODEL PERFORMANCE...
ETA DID WELL YESTERDAY SHOWING 700 MB SHORTWAVE COUPLED WITH UPPER
LEVEL DIVERGENCE THAT KICKED OFF LAST NIGHT'S ROUND OF CONVECTION...SO
WILL RUN WITH IT TODAY AGAIN.

...TONIGHT...
MOST LIKELY AREA IN OUR CWA FOR ANY SVR STORMS LOOKS TO BE NORTH CENTRAL
NEB. LEFT OVER BOUNDARIES FROM THIS MORNING'S SHOWERS LINGER BETWEEN
ANW AND VTN. LOW LEVEL JET LOOKING GOOD...WITH 50+KTS OVER NORTH
CENTRAL NEB DURING DAY TODAY BRINGING IN MOISTURE. MESOETA SHOWING
CONVECTION INITIATION BETWEEN 04/00Z AND 03Z OVER THE VTN-ANW AREA WITH
ENERGY MOVING INTO NORTH CENTRAL NEB AT THAT TIME. PLENTY OF SUPPORTING
PARAMETERS BY 4/03Z FOR ANW-ONL AREA (MESOETA DERIVED SOUNDING) AND
EASTWARD. CAPES IN THE 2000 RANGE, LI'S OF -6, CAP ONLY 55-80 J/KG,
0-3KM SR HELICITY 282. ETA UPPER LEVEL DIVERGENCE BULLSEYED IN THE
VICINITY OF OLU AREA BY 06Z INDICATES CONVECTION MAY START IN NORTH
CENTRAL AND MOVE EAST. IF YOU THINK TONIGHT LOOKS GOOD, WAIT UNTIL
FRIDAY AFTERNOON/EVENING FOR THAT SAME AREA! WILL STICK WITH 50 POPS
FOR TNT IN N CENTRAL. WAITING TO SEE IF I WILL NEED TO PUT IN SCT TSRA
IN LBF ZONES AS THINGS DEVELOP ALONG DRY LINE THIS AFT.

THINGS LOOK LIKE THEY WILL SETTLE DOWN OVERNIGHT DURING EARLY MORNING
HOURS AS MCS MOVES EAST OUT OF OUR CWA.

...FRIDAY/NIGHT...
VERY UNSTABLE AIR SETS THE STAGE FOR MORE CHANCES OF CONVECTION IN
CENTRAL AND NORTH CENTRAL NEB. THETA-E RIDGE TREMENDOUS 00Z SAT OVER
HOLT COUNTY WITH CAPES 5600+. UNFORTUNATELY WE LOSE UPPER LEVEL SUPPORT
OVER EASTERN PART OF THE STATE...AND A PIECE OF ENERGY ENTERS PANHANDLE
INSTEAD. PERHAPS LEFTOVER BOUNDARIES FROM ANYTHING THAT MIGHT FIRE
TONIGHT COULD HELP GET THINGS GOING FRIDAY IN NORTH CENTRAL AS IT WON'T
TAKE MUCH. 7H HAS A LITTLE BIT OF ENERGY ENTERING THAT AREA. WILL LEAVE
POPS IN...PERHAPS BOOST A NOTCH. REST OF FA...A LITTLE SUBSIDENCE (NEG
OMEGA AT H7 BY 18Z OVER SW.) ALSO GOING TO GO BREEZY DURING THE DAY FOR
NORTH CENTRAL ZONES...10-20 MPH ELSEWHERE.

...SAT...
QUITE A DIFFERENCE BETWEEN NGM AND AVN/MRF MODELS FOR SAT. NGM BRINGS
COOLER WX...WHILE AVN KEEPS COLD FRONT JUST TO THE WEST WITH SHORT WAVE
COMING IN. NGM APPEARS TO BE THE OUTLIER WITH PERSISTENT SW FLOW. WILL
PUT 20 OR 30 POPS IN FOR AFTERNOON ACROSS FA...POSSIBLY LINGERING INTO
SUNDAY MORNING. ETA PUTS MORNING STRATUS LEFT OVER FROM MCS (IF NOT SOME
FOG) IN VTN-ONL AREA.

...EXTENDED SUN/MON/TUE...
COLD FRONT/LEE SIDE TROF SETS UP BY 00Z SUNDAY PROGGED TO MOVE TO
WESTERN NEB SUNDAY AND LINGER THERE (MRF.) PROBABLY GO WITH A CHANCE OF
THUNDERSTORMS SUN AND TUE AS WE REMAIN IN SfOUTHWEST FLOW WITH A TROF
MOVING THROUGH AGAIN TUESDAY.  A LITTLE BIT OF RIDGING MONDAY MAY LET
US DRY OUT FOR A DAY.

.LBF...NONE

SLM