Severe Thunderstorm Warning 123, NWS Hastings, NE

SOUTH CENTRAL NEBRASKA/NORTH CENTRAL KANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
230 PM CDT MON JUN 4 2001

...1ST PERIOD PCPN CHCS MAIN CONCERN...

UAA THIS AM HAD POWERFUL LATE SEASON? UPPER LOW SPINNING IN WRN MT.
WV IMAGERY SHOWS LOW HAS WOBBLED NNW AS ONE WV LIFTED NE ON ERN EDGE
OF IT & 2ND WV DROPPED INTO ITS BASE THIS AM ON A 90KT H3 JET. THIS
2ND WV WL BE THE MAIN CATALYST FOR OUR WX THRU TOMR...AS SOUTH FLOW
CONTS TO INCREASE IN RESPONSE TO IT...USHERING VERY MOIST & UNSTABLE
AIR IN KS/OK UP & OVER UNSEASONABLY COLD LLVL AIR WHICH CONTINUES TO
FUNNEL INTO AREA OFF HI PRES IN THE UPPER MS VALLEY.

AT THE SFC...LO PRES WAS POSITIONED JUST S OF GBD AT NOON W/ WARM
FRONT LIFTING SLOWLY THRU KICT. VISIBLE IMAGERY SHOWING GOOD BREAKS
IN STRATUS THRU SE KS. PRES ALSO BEGINNING TO FALL OVER THE HI PLNS
AS UPPER WV EJECT AROUND MT LO. NET EFFECT WL BE TO REPOSITION SFC
LO IN WRN KS/ERN CO BY THIS EVENING. OVERRUNNING...AS IS EVIDENT IN
PROFILERS W/ H85 FRONT NEAR NEB/KS BORDER...IS ALREADY PRODUCING
WIDESPREAD DZ/FOG W/ EMBEDDED SHRAS. THIS PRETTY MUCH ASSOCD W/ SE
EDGE OF 1ST BIG UPPER WV MENTIONED.

BASIC SCENARIO IS FOR THIS INITIAL PCPN TO CONT TO FILL IN AND LIFT
THRU NEB...THEN MAIN EVENT TO SET UP LATE TODAY/TONIGHT AS WARM FRONT
LIFTS FURTHER NORTH & TSRAS FIRE W/ INCREASING VVELS/LLVL JET ASSOCD
W/ NEXT UPPER WV. LOOKS SOMEWHAT SIMILAR TO LAST NIGHT/S SETUP WHERE
ONE AREA OF TSRAS FIRED CLOSER TO UPPER LVL ENERGY AND LIFTED NW OF
CWA...AND OTHER BIG AREA FIRED ON NOSE OF LLVL JET...MAINLY JUST EAST
OF CWA. DIFFERENCE W/ BE LLVL JET POINTED MORE DIRECTLY INTO CWA...
LIKELY ALLOWING FOR MUCH MORE ACTIVITY...ESP IN SRN 1/3 OF CWA...
BEFORE MCS SHIFTS EAST TOWARD TOMR AM.

MAIN THREAT TNGT WILL BE HEAVY RAIN AS H85 DWPTS TOP 15C AND PWATS
TOP 1.5 IN. W/ FFG ONLY IN THE 1-1.5 IN RANGE IN SRN CNTYS & AFTER
COORD W/ OAX/TOP...WL OPT FOR A FLASH FLOOD WATCH TNGT FOR NC KS &
AND IN NEB CNTYS GENERALLY SE OF HSI.

BEYOND THAT...A FEW LINGERING SHRAS TOMR AM W/ GIVE WAY TO P SUNNY
SKIES & SLIGHTLY MILDER TEMPS AS SYS PASSES NE....ALBEIT 10 DEGS OR
SO COLDER THAN AVG STILL. THIS TREND TO CARRY THRU THE WEEK W/ OUR
FIRST REALISTIC CHC AT WIDESPREAD 80+ TEMPS COMING BY FRI. MDLS ARE
IN DARN GOOD AGREEMENT IN LARGE SCALE PATTERN BY WEEKEND/EARLY NEXT
WEEK...IN BUILDING A RIDGE OVER AREA IN RESPONSE TO ANOTHER MONSTER
UPPER LO MOVING ONSHORE IN THE PAC NW. HENCE...A GOOD WARMUP LOOKS
TO BE FINALLY MATERIALIZING.

DRY FCST CURRENTLY IN EXTENDED IS BY NO MEANS A CERTAINTY. THERE ARE
STRONG SUGGESTIONS FROM MDLS WE MAY HAVE TO DEAL W/ NW FLOW WAVES
BEFORE SW US RIDGE BUILDS FULLY INTO AREA. CAN MAKE A PRETTY GOOD
ARGUMENT FOR SCT SHRAS/TSRAS THU/FRI & PERHAPS EVEN SAT. WILL REDO
EXTENDED SOME & INCLUDE PCPN CHCS THRU LATE WEEK AT LEAST.

.GID...FLASH FLOOD WATCH NEZ064-076-077-085>087-KSZ005>007-017>019.

GURNEY