Alert archive / Nebraska / Flash Flood Watches in 2018

Flash Flood Watch 8, NWS Omaha, NE

September 1, 201816 counties in Nebraska; 7 counties in Iowa

NWS Omaha, NE issued this flash flood watch at Sep 1, 2018, 5:15 PM CDT for 16 counties in Nebraska; 7 counties in Iowa. It was in force for 44 hr.

The area

The counties it named.

The facts

Issued
Sep 1, 2018, 5:15 PM CDT (22:15 UTC)
Expired
Sep 3, 2018, 1:00 PM CDT
In force
44 hr
Issued by
NWS Omaha, NE
Flood severity
None
All 23 counties

Fremont County, IA, Harrison County, IA, Mills County, IA, Montgomery County, IA, Page County, IA, Pottawattamie County, IA, Shelby County, IA, Butler County, NE, Cass County, NE, Douglas County, NE, Gage County, NE, Jefferson County, NE, Johnson County, NE, Lancaster County, NE, Nemaha County, NE, Otoe County, NE, Pawnee County, NE, Richardson County, NE, Saline County, NE, Sarpy County, NE, Saunders County, NE, Seward County, NE, Washington County, NE

The radar

The Omaha radar (KOAX), 54 km from the middle of the area, began a volume at 22:15 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.

What forecasters said that day

The local office's own words before this flash flood watch 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 flash flood watch went out at Sep 1, 4:26 PM CDT, 49 minutes earlier.

Area forecast discussion, Sep 1, 4:26 PM CDT, 49 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>
Hazardous weather outlook, Sep 1, 4:58 PM CDT, 17 minutes before
Hazardous Weather Outlook
National Weather Service Omaha/Valley NE
458 PM CDT Sat Sep 1 2018

IAZ043-055-056-069-079-080-090-091-NEZ011-012-015>018-030>034-
042>045-050>053-065>068-078-088>093-021200-
Monona-Harrison-Shelby-Pottawattamie-Mills-Montgomery-Fremont-
Page-Knox-Cedar-Thurston-Antelope-Pierce-Wayne-Boone-Madison-
Stanton-Cuming-Burt-Platte-Colfax-Dodge-Washington-Butler-
Saunders-Douglas-Sarpy-Seward-Lancaster-Cass-Otoe-Saline-
Jefferson-Gage-Johnson-Nemaha-Pawnee-Richardson-
458 PM CDT Sat Sep 1 2018

This Hazardous Weather Outlook is for portions of southwest
Iowa...west central Iowa...east central Nebraska...northeast
Nebraska and southeast Nebraska.

.DAY ONE...Tonight and Sunday

Severe thunderstorms are expected through much of the evening,
especially along and south of Interstate 80. The best timing for
severe weather will from around 6 to 7 pm, through about 3 to 5
am. A few storms could approach severe limits with winds 60 mph
or higher, hail of 1 to 2 inches in diameter, and 1 to 2 inches
of rain. Those with outdoor plans this evening should remain
weather aware and be ready to implement a severe weather plan at a
moments notice.

There could be flash flooding tonight, especially if several
rounds of storms move over the same locations.

Minor flooding will continue along the Missouri River upstream of
Lewis and Clark Lake in northwest Knox county.

.DAYS TWO THROUGH SEVEN...Sunday night through Saturday

Scattered thunderstorms remain in the forecast for Sunday through
Monday. Some strong storms and areas of locally heavy rain will be
possible, especially from late Sunday afternoon into Monday
morning. Some flash flooding could develop. Total rainfall
through Monday could reach 3 to 5 inches in some spots across east
central Nebraska and western Iowa.

The weather pattern should remain active through at least mid
week, with a continued chance for thunderstorms just about every
day.

Minor flooding will continue along the Missouri River upstream of
Lewis and Clark Lake in northwest Knox county. With the expected
heavy rains through the remainder of the Labor Day weekend,
additional river flooding could develop.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed in some areas tonight, primarily
across southeast Nebraska and southwest Iowa.

Pearson

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 1, 2:29 AM CDTSpecial Weather StatementOAXPlatte46 min
Sep 1, 2:50 AM CDTSevere Thunderstorm WarningOAXMadison, Platte25 min
Sep 1, 3:17 AM CDTSpecial Weather StatementOAXColfax, Platte43 min
Sep 1, 4:07 AM CDTSpecial Weather StatementOAXCuming, Stanton, Thurston38 min
Sep 1, 5:20 AM CDTSpecial Weather StatementOAXDouglas40 min
Sep 1, 5:23 AM CDTSpecial Weather StatementOAXCass, Sarpy37 min
Sep 1, 5:36 AM CDTSevere Thunderstorm WarningOAXSarpy24 min
Aug 31, 9:33 PM CDTSpecial Weather StatementOAXPottawattamie27 min
Aug 31, 11:19 PM CDTSpecial Weather StatementOAXMills26 min
Aug 31, 11:53 PM CDTSpecial Weather StatementOAXPottawattamie37 min
Aug 31, 11:54 PM CDTSpecial Weather StatementOAXPottawattamie36 min
Sep 1, 12:22 AM CDTSpecial Weather StatementOAXMills23 min
Sep 1, 12:24 AM CDTSpecial Weather StatementOAXPottawattamie36 min
Sep 1, 12:42 AM CDTSpecial Weather StatementOAXMontgomery33 min
Sep 1, 12:54 AM CDTSpecial Weather StatementOAXPottawattamie36 min
Sep 1, 1:10 AM CDTSevere Thunderstorm WarningOAXMontgomery35 min
Sep 1, 1:38 AM CDTSpecial Weather StatementOAXCass37 min
Sep 1, 2:16 AM CDTSpecial Weather StatementOAXCass29 min
Sep 1, 5:58 AM CDTSevere Thunderstorm WarningOAXMills, Montgomery, Pottawattamie32 min
Sep 1, 6:09 AM CDTSpecial Weather StatementOAXMontgomery36 min
Sep 1, 6:19 AM CDTSevere Thunderstorm WarningOAXMontgomery, Pottawattamie41 min

Nearby

Flash Flood Watches in Nebraska, 2018Flash Flood Watches in Iowa, 2018Every flash flood watch 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; radar from the NEXRAD Level II archive.