Alert archive / Nebraska / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 45, NWS Omaha, NE

May 25, 2018Washington County, Nebraska; Harrison County, Iowa

NWS Omaha, NE issued this severe thunderstorm warning at May 25, 2018, 3:35 PM CDT for Washington County, Nebraska; Harrison County, Iowa. It was in force for 25 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
May 25, 2018, 3:35 PM CDT (20:35 UTC)
Expired
May 25, 2018, 4:00 PM CDT
In force
25 min
Issued by
NWS Omaha, NE
Area
Storm-based polygon
Hail
1.0 in
Wind
50.0 mph

Counties Harrison County, IA, Washington County, NE

The radar

The Omaha radar (KOAX), 43 km from the middle of the area, began a volume at 20:35 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 8.6 hours before the alert went out and 43 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Omaha, NE at 12:00Z on 2018-05-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 502 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 12:00Z on 2018-05-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 135 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
502 J/kg
Mixed-layer CIN
-278 J/kg
Mixed-layer LCL
1260 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
135 m²/s²
0-3 km storm-relative helicity
133 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Omaha, NE wrote its last area forecast discussion before this severe thunderstorm warning went out at May 25, 2:45 PM CDT, 50 minutes earlier.

Area forecast discussion, May 25, 2:45 PM CDT, 50 minutes before
Area Forecast Discussion
National Weather Service Omaha/Valley NE
245 PM CDT Fri May 25 2018

.SHORT TERM...(Tonight through Monday)
Issued at 241 PM CDT Fri May 25 2018

There is very weak trough moving through the area currently, which
has triggered a lone thundershower between Fremont and Blair. There
is also a secondary weak surface trough moving into north central
NE with a couple of showers developing within a towering cu field
south of Valentine. A few of the high res models, including ESRL
HRRR/HRRR/Rap and the GFS hint at a small chance of storms along
these troughs as they moves into our area through the evening,
but there isn't really any upper level support. Will continue to
monitor near term trends, but except for a couple of showers or
storms, most of the area could remain dry tonight.

The bigger picture this weekend will be hot and dry conditions
developing as upper level ridging builds onto the Plains out of
the Rockies. This will result in highs reaching the mid to upper
90s the next couple of days, which would tie or break records in
some locations both Saturday and Sunday (see Climate section for
details). Highs still in the lower 90s on Memorial Day, but not
warm enough to break records this day. The upper ridge also shifts
slightly east by Monday, which could allow isolated storms to
impact eastern NE, but otherwise, we're looking at dry holiday
Memorial Day weekend, which hasn't happened in recent memory.
Welcome to Summer.

.LONG TERM...(Monday night through Friday)
Issued at 241 PM CDT Fri May 25 2018

Active weather returns Tuesday night into early Wednesday as an
upper trough moves into the area. Thunderstorms become likely
during this time, some of which could be strong Tuesday
afternoon and evening. Low confidence in the remainder of the
forecast as ECMWF suggests storms on Thursday, but GFS is dry.
Well above normal temperatures continue through the extended
period.

&&

.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1221 PM CDT Fri May 25 2018

VFR conditions will prevail thru the fcst pd.

&&

.CLIMATE...
Issued at 241 PM CDT Fri May 25 2018

Max temp records next few days:

                    OMAHA     LINCOLN    NORFOLK
                  =================================
  Friday, May 25   97/1967    98/1967    103/1967
Saturday, May 26   96/1912*   98/1912     95/1914*
  Sunday, May 27   94/2012*   95/1966*    93/2006*
  Monday, May 28   97/1895    98/1895    100/1974

* Record could be tied or broken based on the upcoming forecast.

Based on the upcoming forecast, we also have the chance of tying
the record of consecutive highs 90 or higher for the Month of May,
which is 6 from May 20-25, 1921.

&&

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

SHORT TERM...DeWald
LONG TERM...DeWald
AVIATION...DEE
CLIMATE...DeWald
Hazardous weather outlook, May 25, 11:41 AM CDT, 3 hours 54 minutes before
<!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>

In the hours before

Special weather statement, May 25, 3:19 PM CDT, 16 minutes before
Special Weather Statement
National Weather Service Omaha/Valley Nebraska
319 PM CDT FRI MAY 25 2018

IAZ055-069-NEZ044-045-052-252045-
Pottawattamie IA-Harrison IA-Washington NE-Douglas NE-Dodge NE-
319 PM CDT FRI MAY 25 2018

...SPECIAL WEATHER STATEMENT...

At 318 PM CDT, Doppler radar was tracking a strong thunderstorm near
Kennard, or 14 miles northwest of Omaha, moving east at 25 mph.

Half inch hail and winds in excess of 30 mph will be possible with
this storm.

Locations impacted include...
Northern Omaha, Blair, Missouri Valley, Arlington, Underwood, Fort
Calhoun, Kennard, Bennington, Crescent, McClelland, Washington,
Wilson Island State Park, Desoto Bend National Wildlife Refuge and
Hitchcock Nature Center.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
office in Omaha.

&&

LAT...LON 4139 9637 4151 9639 4157 9567 4130 9566
TIME...MOT...LOC 2018Z 269DEG 24KT 4143 9618

DEE
Special weather statement, May 25, 3:26 PM CDT, 9 minutes before
Special Weather Statement
National Weather Service Omaha/Valley Nebraska
326 PM CDT FRI MAY 25 2018

IAZ055-069-NEZ034-045-252100-
Pottawattamie IA-Harrison IA-Burt NE-Washington NE-
326 PM CDT FRI MAY 25 2018

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN POTTAWATTAMIE...
SOUTHWESTERN HARRISON...SOUTHEASTERN BURT AND CENTRAL WASHINGTON
COUNTIES UNTIL 400 PM CDT...

At 326 PM CDT, Doppler radar was tracking a strong thunderstorm 7
miles west of Blair, or 25 miles northwest of Omaha, moving northeast
at 10 mph.

Dime size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Blair, Missouri Valley, Fort Calhoun, Mondamin, Kennard, Modale,
Herman, Desoto Bend National Wildlife Refuge and Wilson Island State
Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 4145 9630 4161 9641 4184 9609 4147 9584
TIME...MOT...LOC 2026Z 241DEG 6KT 4157 9628

KERN

The office that day

Everything else NWS Omaha, NE issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 25, 3:19 PM CDTSpecial Weather StatementOAXDouglas26 min
May 25, 3:26 PM CDTSpecial Weather StatementOAXWashington34 min
May 25, 3:58 PM CDTSpecial Weather StatementOAXWashington32 min
May 25, 4:25 PM CDTSpecial Weather StatementOAXBoone50 min
May 25, 4:30 PM CDTSpecial Weather StatementOAXWashington45 min
May 25, 4:56 PM CDTSpecial Weather StatementOAXColfax49 min
May 25, 5:26 PM CDTSpecial Weather StatementOAXBoone49 min
May 25, 5:38 PM CDTTornado Warning Tornado observedOAXBoone37 min
May 25, 6:10 PM CDTSpecial Weather StatementOAXColfax50 min
May 25, 6:53 PM CDTSpecial Weather StatementOAXColfax52 min

Nearby

Severe Thunderstorm Warnings in Nebraska, 2018Severe Thunderstorm Warnings in Iowa, 2018Every severe thunderstorm warning in 2018

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.