Hail in Nebraska, March 24, 2007

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
255 PM CDT SAT MAR 24 2007

.SHORT TERM...LATEST WATER VAPOR IMAGERY ALONG WITH PAST MORNING
UPPER AIR DATA REVEALS A STRONG UPPER WAVE SPINNING SLOWLY NORTHEAST
ACROSS THE CENTRAL AND SOUTHERN ROCKIES.  SEVERAL SPOKES OF ENERGY
ARE SEEN ROTATING AROUND THIS WAVE WITH THE MOST NOTABLE STRETCHING
FROM EASTERN COLORADO INTO CENTRAL OKLAHOMA.  CURRENT OBJECTIVE
SURFACE ANALYSIS SHOWS A DEEP AREA OF LOW PRESSURE ACROSS NORTHEAST
COLORADO WITH A LIFTING WARM FRONT SEEN EXTENDING EAST INTO CENTRAL
NEBRASKA WHILE A DRYLINE IS EXTENDING SOUTH INTO WESTERN KANSAS.
DECENT LOW LEVEL MOISTURE EXISTS AHEAD OF THIS DRYLINE WITH
DEWPOINTS IN THE MID 50S TO LOWER 60S...ALTHOUGH LAPS AND RUC
ANALYSIS DATA INDICATES ONLY WEAK INSTABILITY AT THIS POINT WITH
CAPES IN THE 200 TO 600 J/KG RANGE.

ACTIVE WEATHER NIGHT SHAPING UP FOR FOR THE FORECAST AREA AS THE
AFOREMENTIONED UPPER WAVE SLIDES NORTHEAST FROM CENTRAL COLORADO
INTO SOUTHERN SD BY SUNRISE.  THIS WAVE WILL ALSO PUSH THE
ASSOCIATED SURFACE LOW NORTHEAST INTO THE DAKOTAS WITH THE TRAILING
DRYLINE SURGING INTO CENTRAL SECTIONS OF KANSAS AND NEBRASKA THIS
EVENING.  MAIN QUESTION IS THE EXTENT AND LOCATION OF CONVECTION
DEVELOPING WITH THIS SYSTEM.  REGIONAL RADAR MOSAIC ALREADY SHOWS AN
AREA OF CONVECTION CLOSER TO THE UPPER LOW OVER EASTERN COLORADO
WITH THE MODELS ALL PUSHING THIS CONVECTION NORTHEAST WITH THE UPPER
SYSTEM.  GIVEN THE TRACK OF THE UPPER LOW...THE BEST CHANCE OF
PRECIPITATION LOOKS TO BE WEST OF A SAINT PAUL TO KEARNEY TO
PHILLIPSBURG LINE.  HOWEVER...A CHANCE WILL ALSO EXIST FURTHER EAST
ALONG THE ADVANCING DRYLINE WITH DECENT HEIGHT FALLS ALOFT EXPECTED
TO ERODE THE CAP AND BRING ISOLATED TO SCATTERED CONVECTION TO AREAS
EAST OF HIGHWAY 281. ALTHOUGH THE MODELS ARE ONLY SHOWING MODEST
INSTABILITY IN THE 500 TO 700 J/KG RANGE...STRONG DEEP LAYER IN
EXCESS OF 50 KTS WILL SET THE STAGE FOR A FEW STORMS TO BECOME
SEVERE.  LOWER CAPE WILL LIMIT TORNADO POTENTIAL...ALTHOUGH A FEW
BRIEF TORNADOES MAY BE POSSIBLE.

THE UPPER WAVE IS THEN SHOWN TO LIFT NORTHEAST INTO THE UPPER
MIDWEST SUNDAY INTO SUNDAY NIGHT WITH SUBSIDENCE SPREADING INTO THE
FORECAST AREA BEHIND THIS EXITING SYSTEM.  THIS WILL BRING A DRY
CONDITIONS TO THE AREA SUNDAY AND SUNDAY NIGHT ALTHOUGH BREEZY
SOUTHWEST WINDS WILL PREVAIL MOST OF SUNDAY.  WILL AIM FOR AFTERNOON
HIGHS IN THE MID 70S TO NEAR 80 FOR HIGHS.

.LONG TERM...12Z MONDAY THROUGH SATURDAY. MILD TEMPERATURES LOOK TO
CONTINUE THROUGH THE EXTENDED PERIOD WITH THE BEST CHANCE FOR
PRECIPITATION COMING MID-WEEK.

THE PERIOD STARTS OFF UNSEASONABLY WARM UNDER THE INFLUENCE OF A
SOUTHWEST FLOW ALOFT AND SOUTHERLY SURFACE FLOW. H85 TEMPS CLIMB
INTO THE MID TEENS AND WITH FORECAST SOUNDINGS INDICATING MIXING TO
THIS LEVEL AND POSSIBLY ABOVE...MAX TEMPS SHOULD REACH THE UPPER 70S
TO NEAR 80F. A SOUTHERN STREAM SHORTWAVE SLIDES THROUGH THE
SOUTHWEST FLOW DURING THE AFTERNOON HOURS...BUT IT APPEARS THAT
ASSOCIATED THUNDERSTORMS WITH THIS FEATURE WILL REMAIN SOUTHEAST OF
THE CWA PER THE PROGGED TRACK. THUS HAVE LEFT FORECAST DRY FOR NOW
AND WILL CONTINUE TO MONITOR FOR ANY NORTHERLY TREND TO SHORTWAVE
TRACK. LOW-LEVEL SOUTHERLY WINDS INCREASE ON TUESDAY IN A TIGHTENING
PRESSURE GRADIENT AS DEEP SURFACE LOW TRACKS ACROSS THE ROCKIES.
MILD TEMPERATURES CONTINUE WITH LOW-LEVEL MOISTURE INCREASING PER
PERSISTENT SOUTHERLY FLOW. THE LLJ KICKS UP TO AROUND 40 KTS TUESDAY
NIGHT AHEAD OF APPROACHING SYSTEM AND RESULTANT THETA-E ADVECTION
MAY TRIGGER SOME SHOWERS AND THUNDERSTORMS OVERNIGHT. THE PARENT
UPPER LOW AND ATTENDANT SURFACE LOW PUSH NORTHEAST INTO THE NORTHERN
PLAINS ON WEDNESDAY...DRAGGING A DRYLINE EASTWARD THROUGH THE
CENTRAL PLAINS DURING THE DAY. THUNDERSTORM CHANCES WITH THIS SYSTEM
REMAIN IN QUESTION WITH LATEST RUNS OF THE GFS PUSHING THE DRYLINE
THROUGH THE MAJORITY OF THE CWA BY 18Z WITH A PRONOUNCED DRY SLOT
OVERSPREADING THE AREA. THE ECMWF REMAINS SLOWER WITH THE
PROGRESSION OF THE SYSTEM AND HAVE MAINTAINED SIMILAR POPS FROM
YESTERDAY. COULD SEE SOME SEVERE ACTIVITY WITH STORMS THAT DO
DEVELOP WEDNESDAY AFTERNOON/EVENING...THE MAIN QUESTION WILL BE HOW
FAR EAST DRYLINE PUSHES BEFORE STORMS INITIATE.

TEMPERATURES COOL BEHIND THE COLD FRONTAL PASSAGE WEDNESDAY NIGHT.
MODELS DISAGREE ON AMOUNT OF COOLING FOR THURSDAY AS THE ECMWF HAS A
MUCH STRONGER SECONDARY VORT LOBE THAT IT SWINGS THROUGH THE MEAN
TROUGH...IN TURN PULLING COOLER AIR INTO THE REGION VERSUS THE GFS.
HAVE STAYED SOMEWHERE IN BETWEEN AT THIS POINT AND A LITTLE COOLER
THAN HPC GUIDANCE NUMBERS. COOLER AIR CONTINUES TO SPILL SOUTH FRIDAY
AND SATURDAY ON BACKSIDE OF VERTICALLY STACKED LOW SLIDING
EAST/NORTHEAST ACROSS SOUTHERN CANADA. HOWEVER...EVEN WITH THE COOL
DOWN TEMPERATURES REMAIN ABOVE AVERAGE WITH HIGHS IN THE UPPER 50S
TO MID 60S AND LOWS IN THE 30S TO AROUND 40.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE HASTINGS NE
640 PM CDT SAT MAR 24 2007

NEZ060-072-082-251200-
DAWSON-GOSPER-FURNAS-
640 PM CDT SAT MAR 24 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTH CENTRAL
NEBRASKA WEST OF HIGHWAY 183.

.DAY ONE...TONIGHT.

THUNDERSTORMS ACROSS NORTHWEST KANSAS AND SOUTHWEST NEBRASKA WILL
CONTINUE TO DEVELOP AND MOVE NORTHEAST THIS EVENING AS A LOW
PRESSURE SYSTEM LIFTS NORTHEAST ACROSS THE REGION. SOME OF THESE
THUNDERSTORMS MAY BE SEVERE...WITH THE PRIMARY THREATS BEING
WIND GUSTS IN EXCESS OF 60 MPH AND HAIL TO THE SIZE OF
QUARTERS. ONE OR TWO BRIEF WEAK TORNADOES ARE ALSO POSSIBLE...AND
A TORNADO WATCH IS IN EFFECT FOR DAWSON...GOSPER...AND FURNAS
COUNTIES THROUGH 10 PM CDT. THE SEVERE WEATHER THREAT WILL RAPIDLY
DIMINISH AFTER 10 PM...HOWEVER THUNDERSTORMS WILL INTO THE
OVERNIGHT HOURS.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY.

THUNDERSTORM CHANCES RETURN TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...
WITH SOME STRONG TO SEVERE THUNDERSTORMS POSSIBLE WEDNESDAY
AFTERNOON AND EVENING.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL LIKELY BE NEEDED THROUGH 10 PM TONIGHT.

&&

MORE INFORMATION MAY BE OBTAINED AT THE FOLLOWING WEB PAGE:
   HTTP://WWW.WEATHER.GOV/HASTINGS  (ALL LOWERCASE)

KSZ005>007-017>019-NEZ039>041-046>049-061>064-073>077-083>087-
251200-
PHILLIPS-SMITH-JEWELL-ROOKS-OSBORNE-MITCHELL-VALLEY-GREELEY-NANCE-
SHERMAN-HOWARD-MERRICK-POLK-BUFFALO-HALL-HAMILTON-YORK-PHELPS-
KEARNEY-ADAMS-CLAY-FILLMORE-HARLAN-FRANKLIN-WEBSTER-NUCKOLLS-
THAYER-
640 PM CDT SAT MAR 24 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTH CENTRAL
NEBRASKA ALONG AND EAST OF HIGHWAY 183...AND PORTIONS OF NORTH CENTRAL
KANSAS.

.DAY ONE...TONIGHT.

THUNDERSTORMS REMAIN POSSIBLE ACROSS THE OUTLOOK AREA THIS EVENING
AND OVERNIGHT. AN ISOLATED SEVERE THUNDERSTORM IS POSSIBLE...WITH
WIND GUSTS AROUND 60 MPH AND HAIL TO THE SIZE OF QUARTERS THE
PRIMARY THREATS. THE THREAT FOR SEVERE WEATHER WILL RAPIDLY
DISSIPATE AFTER 10 PM CDT...WITH THUNDERSTORMS ENDING FROM SOUTH
TO NORTH DURING THE LATE EVENING AND OVERNIGHT HOURS.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY.

THUNDERSTORM CHANCES RETURN TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...
WITH SOME STRONG TO SEVERE THUNDERSTORMS POSSIBLE WEDNESDAY
AFTERNOON AND EVENING.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THROUGH 10 PM TONIGHT.

&&

MORE INFORMATION MAY BE OBTAINED AT THE FOLLOWING WEB PAGE:
   HTTP://WWW.WEATHER.GOV/HASTINGS  (ALL LOWERCASE)