Severe Thunderstorm Warning 51, NWS Hastings, NE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
1038 AM CDT SUN JUN 1 2014

.UPDATE...
ISSUED AT 1038 AM CDT SUN JUN 1 2014

COMPLEX EVOLUTION OF CONVECTIVE THREAT TODAY CONTINUES TO UNFOLD.
AS SUGGESTED BY SOME...BUT NOT ALL...MODELS DURING THE LAST 24
HOURS...SEVERAL SHOWERS/GENERALLY WEAK THUNDERSTORMS HAVE IN FACT
FESTERED ALL MORNING SO FAR WITHIN/NEAR THE FAR WESTERN CWA. THIS
SO-FAR ELEVATED ACTIVITY SEEMS BEST TIED TO THE OVERLAP OF THE
LEADING EDGE OF HIGHER DEWPOINTS EVIDENT AROUND 700 MILLIBARS AND
THE LEADING EDGE OF STEEP MID-LEVEL LAPSE RATES ON THE ORDER OF
7-8.5 C BETWEEN 700-500MB. THE BIGGEST QUESTION OF THE DAY
SURROUNDS WHETHER OR NOT THIS ONGOING ACTIVITY IN OUR WEST WILL
CONTINUE TO SLOWLY INTENSIFY AND MAYBE EVEN BECOME MARGINALLY
SEVERE BY EARLY AFTERNOON...OR WHETHER THE "MAIN SHOW" WILL TRULY
HOLD OFF UNTIL THE GENERALLY 3PM-11PM TIME FRAME AS HAS BEEN
EXPECTED. HAVE TWEAKED THE LATEST HAZARDOUS WEATHER OUTLOOK TO
REFLECT THE LATEST THINKING/UNCERTAINTY...BUT BY AND LARGE
EXPECTATIONS FROM LAST NIGHT/EARLY THIS MORNING REMAIN ON TRACK AS
IT WILL TAKE AT LEAST A FEW MORE HOURS FOR MORE SURFACE-BASED
ACTIVITY TO TAKE ROOT. OBVIOUSLY THE EXTENT OF THIS MORNING
CONVECTION AND ITS ASSOCIATED WIDESPREAD CLOUD COVER GRADUALLY
OVERTAKING THE CWA FROM WEST-EAST COULD AT LEAST TEMPORARILY DELAY
LOW-LEVEL DESTABILIZATION AS WELL...BUT FEEL THERE SHOULD BE
ENOUGH FILTERED SUN TO NOT HAVE TOO MUCH EFFECT ON SQUELCHING THIS
HIGH-END SLIGHT RISK SEVERE POTENTIAL PER THE STORM PREDICTION
CENTER. WILL BE INTERESTING TO SEE IF THE DEVELOPING CLUSTER OF
STRONG-SEVERE STORMS CURRENTLY OVER THE WEST-CENTRAL NEB SANDHILLS
STARTS TO MAKE A MORE AGGRESSIVE EASTWARD-PUSH INTO OUR WESTERN
CWA BY EARLY AFTERNOON IF A DECENT COLD-POOL GETS ORGANIZED.

GIVEN THE INCREASING CLOUD COVERAGE AND EARLIER ONSET OF ELEVATED
CONVECTION IN THE WEST...DID NUDGE DOWN HIGH TEMPS AT LEAST 1-2
DEGREES CWA-WIDE...AND MORE LIKE 4 DEGREES IN WEST-CENTRAL/NORTHWEST
ZONES...AS THOSE AREAS SHOULD MOST-STRUGGLE TO REACH LOW 80S.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 420 AM CDT SUN JUN 1 2014

WE ARE EXPECTING A POTENTIALLY VOLATILE AFTERNOON AND EVENING OF
THUNDERSTORMS ACROSS THE CENTRAL PLAINS...AND PRETTY MUCH CENTERED
OVER OUR ENTIRE FORECAST AREA OF SOUTH CENTRAL NEBRASKA AND NORTH
CENTRAL KANSAS.

THIS CURRENTLY APPEARS TO BE A HIGH END SLIGHT RISK DAY FOR SEVERE
THUNDERSTORMS WITH A FEW CONCERNS THAT AT LEAST IN MY MIND WOULD
POTENTIALLY LIMIT IT FROM BEING A MORE SIGNIFICANT EVENT ALTHOUGH
THAT COULD CHANGE DEPENDING ON HOW THINGS EVOLVE. THERE ARE
QUESTIONS MARKS SURROUNDING THE POSSIBILITY OF MORNING CONVECTION
WITH NUMEROUS FORECAST MODELS INDICATING SOME ELEVATED MORNING
CONVECTION WITH RATHER CONTINUOUS ISOLATED TO SCATTERED CONVECTION
AROUND THE AREA UNTIL THINGS REALLY GET GOING WITH AFTERNOON HEATING
BY MID TO LATE AFTERNOON. HOWEVER...ANY MORNING CONVECTION COULD ACT
TO LIMIT OUR AFTERNOON DESTABILIZATION AND ADD SOME OTHER QUESTION
MARKS RELATED TO BOUNDARIES RESULTING FROM EARLY DAY CONVECTION. THE
MORE SUNSHINE WE SEE DURING THE LATE MORNING AND EARLY AFTERNOON
HOURS...THE MORE SEVERE THE AFTERNOON STORMS COULD BECOME.

ALTHOUGH THE PRIMARY THREAT WILL BE SEVERE HAIL AND WIND...THERE
WILL ALSO BE THE POSSIBILITY OF A FEW TORNADOES WITH THE STRONGER
MORE ISOLATED STORMS DURING THE LATE AFTERNOON HOURS PRIOR TO THE
STORMS CONGEALING INTO A LINE/MCS. NUMEROUS FORECAST MODELS INDICATE
WIDESPREAD THUNDERSTORMS EVENTUALLY MERGING INTO A BIG MCS WITH
POSSIBLE BOWING SEGMENTS ENHANCING THE DAMAGING WIND THREAT DURING
THE EVENING HOURS. THE 06Z NAM12 IS SHOWING SOME BETTER SHEAR THAN
SOME OF THE OTHER MODELS WITH 0-1 KM SHEAR VALUES OF AROUND 25 KTS
BY 4 TO 7 PM...WHILE THE 06Z GFS40 INDICATES AROUND 20 KTS OF LOW
LEVEL SHEAR. DEEP LAYER 0-6 KM SHEAR BASED ON NUMEROUS FORECAST
MODELS SHOULD BE OVER 40 KTS AND THE 06Z NAM12 EVEN INDICATES MAYBE
OVER 50 KTS ON THE HIGHER END. THERE IS ALSO GOOD MODEL CONSISTENCY
IN MLCAPE VALUES OF AROUND A JUST OVER 2000 J/KG BY EARLY AFTERNOON.
THE SHORT WAVE THAT WILL ACT AS THE NECESSARY FORCING FOR THIS EVENT
HAS GOOD MODEL SUPPORT IN TRACKING THROUGH THE NORTHERN AND CENTRAL
PLAINS THIS AFTERNOON. SO THE BIG QUESTION MARK IS MORE CENTERED ON
THE LESSER CONVECTION THIS MORNING AND ITS POSSIBLE IMPACT ON THE
LATE DAY CONVECTION. WILL CONTINUE TO KEEP PRECIPITATION CHANCES LOW
THROUGH THE FIRST HALF OF THE DAY...WITH RAPIDLY INCREASING CHANCES
FOR THUNDERSTORMS AS WE HEAD THROUGH THE AFTERNOON WITH THE MOST
LIKELY WINDOW FOR SEVERE CONVECTION ACROSS OUR FORECAST AREA RUNNING
FROM 4 PM UNTIL AROUND 9 PM. SEVERE CONVECTION COULD BE POSSIBLE
OUTSIDE OF THIS WINDOW...BUT THE BRUNT OF THE SEVERE WEATHER SHOULD
OCCUR DURING THESE LATE AFTERNOON TO EARLY EVENING HOURS.

IT WILL BE A WARM STICKY DAY WITH THE HIGH MID 60S DEWPOINTS AND
TEMPERATURES MAXING OUT IN THE MID 80S NORTH TO AROUND 90 ACROSS
NORTHERN KANSAS. THE SOUTH SOUTHEAST SFC WIND WILL BE A BIT BREEZY
DURING THE AFTERNOON AHEAD OF THE APPROACHING TROUGH/COOL FRONT.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 420 AM CDT SUN JUN 1 2014

PRIMARY FORECAST CONCERN THROUGH THE LONG TERM PERIOD REMAINS WITH
MULTIPLE THUNDERSTORM CHANCES...ESP TUES/TUESDAY NIGHT...WHICH LOOKS
TO BE THE NEXT BEST CHANCE FOR SEVERE WEATHER AFFECTING AT LEAST
PART OF THE CWA.

EXPECTING MONDAY INTO A GOOD CHUNK OF MONDAY NIGHT TO BE A LULL IN
THE ACTIVITY FORECAST FOR TODAY AND THE NEXT ROUND MOVING IN TOWARD
TUESDAY.  MONDAY MORNING...THE MAIN MID/UPPER LEVEL SYSTEM LOOKS TO
BE IN PLACE OVER THE DAKOTAS...WITH THE ACCOMPANYING SOUTHWARD
EXTENDING TROUGH AXIS HAVING SHIFTED EAST OF THE CWA...TAKING THE
BETTER PRECIP CHANCES ALONG. OUTSIDE OF THE LATEST RUN OF THE
NAME...MODELS IN GOOD AGREEMENT WITH KEEPING THE FORECAST DRY...WITH
SOME WEAK SHORTWAVE RIDGING BRIEFLY BUILDING IN FROM THE WEST. AT
THE SURFACE...A WEAKER PATTERN IS EXPECTED AS HIGH PRESSURE SLIDES
IN...WITH THE RIDGE AXIS POTENTIALLY RUNNING THROUGH THE CWA. WINDS
WILL BE ON THE LIGHTER SIDE...NWRLY ACROSS NRN PORTIONS WHILE MORE
VARIABLE FURTHER SOUTH. DIDNT MAKE ANY NOTABLE CHANGES TO
TEMPS...WITH HIGHS FORECAST TO REACH INTO THE LOWER/MID 80S.

LATER MONDAY NIGHT/EARLY TUESDAY MORNING...PRECIP CHANCES START TO
WORK THEIR WAY BACK IN FROM THE WEST...AS THE NEXT UPPER LEVEL
DISTURBANCE STARTS TO MOVE THROUGH THE ROCKIES. AT THIS
POINT...FORECAST IS DRY PRIOR TO 06Z...WITH POPS 06-12Z ONLY
AFFECTING THE SWRN THIRD OR SO OF THE CWA. SURFACE LOW PRESSURE IS
STARTING TO BECOME BETTER ORGANIZED...BRINGING MORE S/SERLY WINDS TO
THE CWA. OVERNIGHT LOWS IN THE UPPER 50S TO MID 60S EXPECTED.

THE MOST INTERESTING PERIOD OF THE LONG TERM COMES DURING THE
DAYTIME HOURS TUESDAY/TUESDAY NIGHT. MODELS DEPICTING THAT ACTIVITY
DEVELOPING OVER WRN PORTIONS OF THE CWA WITH THE INCREASED LIFT
AHEAD OF THE DISTURBANCE EARLY TUESDAY MORNING NEVER REALLY GOING
AWAY...BUT EXPECTING THE MAIN SHOW TO BE LATER IN THE DAY AS THE
BETTER LIFT WITH THE DISTURBANCE CONTINUES SHIFTING EAST. ALSO
AIDING IN LIFT ACROSS THE AREA DURING THE DAY IS A MID/UPPER LEVEL
JET STREAK NOSING IN FROM THE SW...ROUGHLY 50-60KT AT 500MB AND ARND
80KTS HIGHER UP. AS THE DISTURBANCE CONTINUES ITS TREK TOWARD THE
PLAINS...SURFACE LOW PRESSURE IS BECOMING BETTER ORGANIZED...AND AS
USUAL...THE MILLION DOLLAR QUESTION IS WHERE IT ENDS UP. AS IT
DEEPENS...THE FRONTAL BOUNDARIES ARE MORE WELL DEFINED...AND WHILE
THE DRYLINE IS MAINLY TO THE W/SW...OUR ISSUE WILL LIE WITH THE WARM
FRONT...AND HOW MUCH NORTHWARD PROGRESS IT MAKES DURING THE DAY. THE
NAM SHOWS A DEEPER LOW DEVELOPING...BY 00Z SHOWING THE LOW CENTERED
ROUGHLY OVER FURNAS COUNTY...WITH THE WARM FRONT MOVING NORTH
QUICKER THROUGH THE CWA AND IS AFFECTING AREAS GENERALLY NORTH OF
INTERSTATE 80. MORE SUPPORT IS TRENDED TOWARD A SLIGHTLY WEAKER
LOW...MORE IN PLACE OVER NWRN KS...AND THE SLOWER MOVING WARM FRONT
CLOSER TO THE HIGHWAY 6 OR NEB/KS STATE LINE AREA. EITHER WAY
POTENTIALLY SPELLS TROUBLE FOR OUR CWA...MORE OF A QUESTION OF HOW
MUCH OF IT...AS MODELS IN BETTER AGREEMENT SHOWING THE WARM SECTOR
SOUTH OF THE FRONT MORE CAPPED/DRY...WITH 700MB TEMPS PUSHING 15C.
MODELS IN GOOD AGREEMENT SHOWING GOOD LOW LEVEL SHEAR/HELICITY AND
DEEP LAYER SHEAR VALUES DEVELOPING...WITH MORE EASTERLY WINDS AT THE
SFC NEAR/NORTH OF THE FRONT...SRLY ACROSS THE AREA AT
850MB...W/SWRLY AT 700/500MB...SOME MODELS SHOWING IN EXCESS OF 50-
60KTS OF DEEP LAYER SHEAR ALREADY DURING THE AFTERNOON HOURS...WITH
THE BETTER LOWER LEVEL SHEAR COMING LATE IN THE DAY/EVENING ONCE THE
LLJ RAMPS UP. ALONG WITH THE SHEAR IS GOOD INSTABILITY...WHICH
MODELS HAVE INCREASED OVER THE PAST 24 HRS...DEWPOINTS IN THE UPPER
60S POOLING ALONG THE WARM FRONT...AND MODELS SHOWING SOME LOCATIONS
WITH MLCAPE VALUES IN EXCESS OF 3000 J/KG. TEMPS A LITTLE TRICKY
WITH THE POTENTIAL OF SCT PRECIP DURING THE DAY AND THE ULTIMATE
LOCATION OF THE SFC FRONT...BUT CURRENT FORECAST CALLING FOR UPPER
70S IN THE FAR NORTH TO NEAR 90 ACROSS NC KS. THE CWA IS ALREADY IN
A SLIGHT RISK AREA IN SPCS DAY 3 OUTLOOK...AND CERTAINLY DONT
DISAGREE...LARGE HAIL/DAMAGING WINDS/HEAVY RAIN OBVIOUSLY A
CONCERN...AND WITH A WARM FRONT DRAPED EAST ACROSS THE AREA THE
TORNADO POTENTIAL IS ALSO A CONCERN.  WILL SEE HOW MODELS TREND WITH
THE SFC LOW/FRONTS IN UPCOMING RUNS...SOME THINGS YET TO IRON
OUT...AND STILL SOME TIME FOR THINGS TO CHANGE WITH IT COUPLE DAYS
OUT YET...BUT CERTAINLY A PERIOD THAT BEARS WATCHING.

OUTSIDE OF THE POTENTIAL FOR SOME LINGERING ACTIVITY EARLY WEDNESDAY
MORNING...EXPECTING IT TO BE RELATIVELY QUIET.  BEYOND THAT THROUGH
SATURDAY...THE FORECAST STARTS TO SOUND A BIT LIKE A BROKEN RECORD.
CONTINUE TO HAVE 20 TO 40 POPS GOING EACH DAY...AS MODELS CONTINUE
TO SHOW GENERALLY ZONAL FLOW IN PLACE IN THE UPPER LEVELS...WITH THE
PERIODIC DISTURBANCES MOVING THROUGH AND BRINGING THOSE PRECIP
CHANCES. CONFIDENCE IN THAT TIME FRAME...ESP WED NIGHT THROUGH
SAT...REMAINS LOW DUE TO MODEL DIFFERENCES WITH TIMING/LOCATION OF
THE DISTURBANCES...BUT COULDNT COMPLETELY RULE ANY PARTICULAR PERIOD
OUT.  TEMPS WED THROUGH SATURDAY NOT EXPECTED TO SEE ANY NOTABLE
SWINGS AT THIS POINT...GENERALLY RANGING FROM THE MID 70S IN THE
NORTH TO UPPER 70S/LOWER 80S IN THE SOUTH.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 531 AM CDT SUN JUN 1 2014

THE WIND WILL REMAIN SOUTHERLY TODAY UNTIL A WEAK COLD FRONT
PASSES THROUGH THIS EVENING. HOWEVER...THE WIND WILL LIKELY BE
GUSTY AND VARIABLE AT TIMES LATE THIS AFTERNOON AND EVENING IN
CLOSE PROXIMITY TO ANY THUNDERSTORMS. THUNDERSTORMS ARE LIKELY BY
LATE AFTERNOON AND THIS EVENING...ESPECIALLY BETWEEN 4 AND 10 PM.
WILL STICK WITH THE VICINITY THUNDERSTORM MENTION UNTIL TIMING
CAN BE BETTER NARROWED DOWN. FOR THE MOST PART CEILINGS AND
VISIBILITY SHOULD BE VFR ALTHOUGH THAT COULD CHANGE WITHIN ANY
THUNDERSTORMS THAT IMPACT KGRI.

&&

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

UPDATE...PFANNKUCH
SHORT TERM...WESELY
LONG TERM...ADO
AVIATION...WESELY

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>