Severe Thunderstorm Warning 35, NWS Omaha, NE

Area Forecast Discussion
National Weather Service Omaha/Valley NE
621 PM CDT Thu May 16 2019

.SHORT TERM...(Tonight through Sunday)
Issued at 312 PM CDT Thu May 16 2019

An intense upper low is currently making its way through the western
US, while a ridge persists over the central states.  Further to our
north, another strong low pressure system is digging through
northern Manitoba and into Ontario.  A surface low associated with
the northern system will continue to drag a frontal boundary through
northern Nebraska and Iowa.  This boundary, currently draped across
the CWA from around Albion through Sioux City, will stall across
the area today and become a focus for potential storm development
this evening. CAMS are still showing a little disagreement on
exact timing and intensity of convection. However, the general
consensus indicates thunderstorm development along the cool edge
of the front beginning around 7-10 pm this evening. Steep mid
level lapse rates around 7-8.5 C/km and around 1500-2000 J/kg of
MLCAPE could contribute to a large hail and damaging wind threat.
Showers and thunderstorms will continue through the overnight
hours, with coverage diminishing early Friday morning.

The threat of severe weather will return by late in the day Friday.
A surface low, associated with the upper level trough over the
western US, will deepen over eastern CO. It will then progress
into central Nebraska by Friday afternoon. This will push the
previously stalled surface boundary to the northern edge of the
CWA. Gusty southerly winds will bring another muggy day with highs
in the upper 80s and dewpoints in the 60s. A few strong to severe storms
could develop along the warm front over northern Nebraska and
Iowa, however the main threat for severe weather will occur with
storms developing over north-central Nebraska late Friday
afternoon and evening. Low level lapse rates will range from
around 6-7 C/km with mid level lapse rates around 7-9 C/km.
MLCAPE will climb to around 2000-3000J/kg by Friday afternoon. 0-6
km bulk shear is expected to range from 30-50 kts across northern
Nebraska. Initial supercell storms will bring a large hail and a
strong wind threat. There will also be at least some potential for
a tornadic development with 150-200 m^2/s^2 of 0- 1 km SRH and
over 20kts of 0-1 km shear. Storms could then merge into a bowing
MCS which would being damaging winds and potentially a few
tornadoes as it passes through eastern Nebraska and into western
Iowa Friday evening and overnight.

The majority of precipitation will move out Saturday morning with
afternoon highs rising into the upper 70s and dewpoints in the 50s
and 60s. There will be another threat for severe weather along a
cold front draped across the southeastern half of the CWA Saturday
afternoon and evening.

.LONG TERM...(Sunday night through Thursday)
Issued at 312 PM CDT Thu May 16 2019

Showers and thunderstorms will continue through Saturday night
before clearing out on Sunday.  Slightly cooler temperatures are
expected into early next week with highs in the upper 60s.

Another intense system will move through the region Monday and
Tuesday bringing some threat for severe weather over southeast
Nebraska and southwest Iowa. Flooding concerns will also increase
into the extended period, given saturated soil conditions and
multiple rounds of potentially heavy rainfall.

&&

.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 612 PM CDT Thu May 16 2019

Expecting thunderstorms to develop tonight along a boundary
between OFK and OMA. Storms could bring MVFR conditions as they
drift southeast overnight, impacting OFK and OMA. While LNK
should miss most of tonights storms, there is a small chance that
they could see a few, but chances were too small to be included in
the TAF. Otherwise, LNK may see some low level wind shear tonight
with conditions improving by Friday morning.

&&

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

SHORT TERM...KG
LONG TERM...KG
AVIATION...HB

<!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>