Severe Thunderstorm Warning 155, NWS Omaha, NE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
317 PM CDT MON JUL 22 2013

.DISCUSSION...
THUNDERSTORMS ARE DEVELOPING AS A COLD FRONT IS MOVING THROUGH
THE AREA. SUBJECTIVE 12Z UPPER AIR ANALYSIS INDICATES BROAD UPPER-
LEVEL TROUGH OVER THE GREAT LAKES...WITH NORTHWEST FLOW ACROSS THE
ROCKIES TO CENTRAL US. A FEW SHORTWAVES WERE NOTED...INCLUDING ONE
IN BC/WA...ANOTHER ON THE ONT/MB BORDER...AND ANOTHER IN CENTRAL
SD/NORTHERN NEB. 850MB LOW WAS CENTERED IN WESTERN ONT...WITH
TRAILING FRONT THROUGH MN/SD/WESTERN NEB. PRONOUNCED DRY TONGUE AT
850MB WAS NOTED FROM THE DAKOTAS INTO EASTERN NEB...THEN WRAPPING
THROUGH KS. MOIST AXIS WAS NOTED FROM NORTHEAST KS INTO NORTHERN
MO...THEN AROUND A SECONDARY FRONT ALONG THE MID TO LOWER MS RIVER
VALLEY. MOISTURE AXIS ALSO WAS NOTED FROM THE MONSOON AREA OF THE
SW ALONG THE FRONT RANGE INTO EASTERN WY/EASTERN MT. HIGHER 700-
500MB LAPSE RATES WERE SUPPRESSED A LITTLE WESTWARD COMPARED TO
YESTERDAY...THOUGH STILL CLOSE TO 20C AT KOAX. SURFACE FRONT AT
19Z EXTENDED FROM AROUND KAEL TO NEAR KSUX TO KBVN...AND A FEW
SHOWERS AND THUNDERSTORMS WERE STARTING TO DEVELOP ALONG THE
FRONT IN IA...WHILE SHOWERS ALSO WERE DEVELOPING IN NORTHEAST KS
IN THE WARM SECTOR.

MAIN FORECAST CONCERNS ARE CONVECTIVE EVOLUTION INTO THIS
EVENING...POTENTIAL FOR SHOWERS/THUNDERSTORMS TOMORROW...AND
POTENTIAL AGAIN ON FRIDAY/SATURDAY.  FRONT SHOULD CONTINUE TO SAG
SOUTHWARD STEADILY THIS AFTERNOON/EVENING...AND EXPECT CONVECTIVE
DEVELOPMENT TO CONTINUE ALONG THE FRONT.  BY 00Z...ACTIVITY SHOULD
BE ALONG/SOUTH OF INTERSTATE 80...AND IT SHOULD PROGRESS OUT OF THE
CWA BY MIDNIGHT.  WITH MLCAPE AROUND 3000-4000 J/KG...AND WITH
AROUND 30KT OF EFFECTIVE BULK SHEAR...A FEW STRONG AND SEVERE STORMS
WILL BE POSSIBLE THIS EVENING...WITH LARGE HAIL AND DAMAGING WINDS
THE MAIN HAZARDS.  STORMS SHOULD BE PROGRESSIVE ENOUGH--AND GROUND
IS DRY ENOUGH--TO PREVENT ANY HEAVY RAIN ISSUES EVEN BENEATH LOCALLY
HEAVY DOWNPOURS.  ALSO...WITH NEARLY NIL LOW-LEVEL SHEAR...DO NOT
EXPECT A TORNADO THREAT.

BY LATE TONIGHT...THE SHORTWAVE IN THE PACIFIC NORTHWEST SHOULD DROP
THROUGH THE ROCKIES AND APPROACH THE HIGH PLAINS.  IN WAKE OF
CONVECTION THIS EVENING...AIRMASS OVER IA/EASTERN NEB SHOULD BE
QUITE STABILIZED AND DRY IN THE MID-LEVELS...WHILE LOW-LEVEL JET
BRINGS MOISTURE TO THE HIGH PLAINS.  ANY SHOWER/THUNDERSTORM
ACTIVITY LATE TONIGHT INTO TUESDAY MORNING SHOULD REMAIN WEST OF THE
CWA FROM CENTRAL SD INTO CENTRAL NEB...MORE IN THE MOISTURE
AXIS/ALONG THE 850MB TEMPERATURE GRADIENT AND CLOSER TO THE
APPROACHING WAVE. BY AFTERNOON...MAY SEE A FEW SHOWERS OR ISOLATED
STORMS DEVELOP INTO EASTERN NEB AND MAYBE SNEAK INTO WESTERN IA AS
THE WAVE MOVES THROUGH. INSTABILITY IS MUCH LESS IMPRESSIVE
TOMORROW...WITH MUCAPE AROUND 1000 J/KG ABOVE AROUND 800MB...BUT
SHOULD BE ADEQUATE FOR SHOWERS AND AT LEAST A LITTLE THUNDER...WITH
ACTIVITY MOVING SOUTH AND OUT OF THE AREA THROUGH THE EVENING HOURS.

WEDNESDAY THROUGH THURSDAY SHOULD BE MAINLY QUIET ACROSS THE AREA AS
MID-LEVEL RIDGE MOVES THROUGH THE AREA...WHILE UPPER-LEVEL DEEP
TROUGH DEVELOPS IN THE CENTRAL ROCKIES.  HAVE BUMPED TEMPS UP JUST A
TOUCH ON THURSDAY IN PARTICULAR...AS MID-LEVEL WARM AIR ADVECTION
BRINGS INCREASING TEMPS.  ALSO KEPT POPS OUT OF THE CWA
THURSDAY...CLOSER TO A SLOWER ECMWF SOLUTION.  BY THURSDAY
EVENING...MAY SEE SHOWERS/STORMS DEVELOP OVER THE AREA AS UPPER
TROUGH APPROACHES.  TRACK AND STRENGTH OF THE UPPER TROUGH IS STILL
IN QUESTION...WITH ECMWF DEEPER AND A LITTLE FURTHER SOUTH THAN THE
GFS...A SOLUTION THAT WOULD BRING THE BEST MOISTURE SOUTH OF THE CWA
WHILE SHOWERS DEVELOP IN A WRAP-AROUND FEATURE TO THE NORTH OF THE
LOW ACROSS IA/NEB.  IN EITHER CASE...CHANCE POPS ACROSS THE AREA
THURSDAY NIGHT INTO FRIDAY SEEM APPROPRIATE...WITH SLIGHT CHANCES
LINGERING INTO SATURDAY.

BEHIND THE LOW...RIDGING AND HIGH PRESSURE LOOK TO DOMINATE FROM
SATURDAY NIGHT THROUGH MONDAY.  HAVE COORDINATED WITH NEIGHBORS TO
DROP OUT ALLBLEND POPS AS REGIME LOOKS QUIET THROUGH AT LEAST EARLY
MONDAY.

MAYES

&&

.AVIATION...
18Z TAFS FOR KOMA...KOFK...KLNK

VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD EXCEPT IN POSSIBLE
TSRA. THIS APPEARS MOST LIKELY AT OMA FROM AROUND 19-22Z AND LNK
AROUND 21-24Z WITH MVFR CIGS/VISBY POSSIBLE. OTHERWISE A SFC CDFNT
WILL MOV THROUGH OFK NEAR 18Z AND OMA/LNK BY AROUND 21Z WITH WINDS
SHIFTING FROM SW TO NW AT ALL LOCATIONS. MOST CLEAR CONDITIONS ARE
EXPECTED OVERNIGHT WITH LIGHT WINDS.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
326 PM CDT MON JUL 22 2013

IAZ043-055-056-069-079-080-090-091-NEZ015-032>034-042>045-050>053-
065>068-078-088>093-231030-
MONONA-HARRISON-SHELBY-POTTAWATTAMIE-MILLS-MONTGOMERY-FREMONT-
PAGE-THURSTON-STANTON-CUMING-BURT-PLATTE-COLFAX-DODGE-WASHINGTON-
BUTLER-SAUNDERS-DOUGLAS-SARPY-SEWARD-LANCASTER-CASS-OTOE-SALINE-
JEFFERSON-GAGE-JOHNSON-NEMAHA-PAWNEE-RICHARDSON-
326 PM CDT MON JUL 22 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHWEST
IOWA...WEST CENTRAL IOWA...EAST CENTRAL NEBRASKA...NORTHEAST
NEBRASKA AND SOUTHEAST NEBRASKA.

.DAY ONE...THIS AFTERNOON AND TONIGHT

SCATTERED THUNDERSTORMS WILL MOVE ACROSS EASTERN NEBRASKA AND
WESTERN IOWA THROUGH THIS EVENING. A FEW OF THE STORMS MAY BE
SEVERE...WITH LARGE HAIL AND DAMAGING WINDS THE MAIN THREATS. THE
GREATEST RISK FOR SEVERE THUNDERSTORMS WILL BE FROM 4 TO 10 PM.
STORMS SHOULD EXIT THE AREA BY AROUND MIDNIGHT.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

A FEW THUNDERSTORMS ARE POSSIBLE ON TUESDAY...MAINLY IN THE
AFTERNOON AND EVENING IN EAST CENTRAL TO SOUTHEAST NEBRASKA.
SEVERE WEATHER IS NOT EXPECTED.

THUNDERSTORMS ARE POSSIBLE FROM THURSDAY NIGHT THROUGH FRIDAY
NIGHT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED THIS AFTERNOON OR
TONIGHT...BUT REPORTS OF HAIL OR DAMAGING WINDS ARE APPRECIATED.

NEZ011-012-016>018-030-031-231030-
KNOX-CEDAR-ANTELOPE-PIERCE-WAYNE-BOONE-MADISON-
326 PM CDT MON JUL 22 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST
NEBRASKA.

.DAY ONE...THIS AFTERNOON AND TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

A FEW THUNDERSTORMS ARE POSSIBLE ON TUESDAY...MAINLY IN THE
AFTERNOON AND EVENING IN EAST CENTRAL TO SOUTHEAST NEBRASKA.
SEVERE WEATHER IS NOT EXPECTED.

THUNDERSTORMS ARE POSSIBLE FROM THURSDAY NIGHT THROUGH FRIDAY
NIGHT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED THIS AFTERNOON OR TONIGHT.

MAYES

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE OMAHA/VALLEY NEBRASKA
603 PM CDT MON JUL 22 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0542 PM     HAIL             2 S WESTON              41.16N 96.74W
07/22/2013  E1.00 INCH       SAUNDERS           NE   PUBLIC

            NICKEL TO QUARTER SIZE

&&

DFOBERT

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE OMAHA/VALLEY NEBRASKA
604 PM CDT MON JUL 22 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0552 PM     HAIL             WESTON                  41.19N 96.74W
07/22/2013  M1.25 INCH       SAUNDERS           NE   TRAINED SPOTTER

&&

DFOBERT

<!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>

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE OMAHA/VALLEY NEBRASKA
655 PM CDT MON JUL 22 2013

IAZ055-069-230030-
POTTAWATTAMIE IA-HARRISON IA-
655 PM CDT MON JUL 22 2013

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN POTTAWATTAMIE AND
HARRISON COUNTIES UNTIL 730 PM CDT...

AT 651 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM NEAR MISSOURI VALLEY...OR 24 MILES NORTH OF
OMAHA...MOVING EAST AT 5 MPH.

HAIL UP TO THE SIZE OF NICKELS WILL BE POSSIBLE WITH THIS STORM
ALONG WITH BRIEF VERY HEAVY RAIN.

LOCATIONS IMPACTED INCLUDE...
MISSOURI VALLEY...LOGAN AND MODALE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THIS STORM...AND MAY LEAD
TO FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
ROADWAYS.

&&

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT
MONDAY AFTERNOON FOR CENTRAL NEBRASKA.

LAT...LON 4149 9558 4146 9594 4166 9607 4170 9572
TIME...MOT...LOC 2351Z 251DEG 9KT 4160 9585

ZAPOTOCNY

<!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>