078
FXUS63 KOAX 151106
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
606 AM CDT Sat Jun 15 2024

.KEY MESSAGES...

- Non severe thunderstorms early this morning, then an
  additional chance of strong and possibly severe thunderstorms
  this afternoon. All modes of severe weather would be possible
  from 4 pm through midnight, mainly along and south of a
  Columbus to Sioux City line.

- Very hot temperatures expected Sunday and Monday with
  afternoon heat index values 98 to 103 each day.

- Daily storm chances exist at least somewhere in our coverage
  area every day from Sunday night through next week, and
  especially north of Interstate 80. Each round of storms will
  have potential for some severe weather and locally heavy
  rains.

&&

.DISCUSSION...
Issued at 357 AM CDT Sat Jun 15 2024

A line of non severe thunderstorms is currently moving through
eastern NE early this morning. Wind gusts have ranged from 40 to
55 mph along with some small hail. This line will continue to
push into western IA before daybreak, with an hour or two of
stratiform rain trailing behind the main line. The rain will end
from west to east with the bulk of it over by 10 am. Then
there will be a few hour break from late morning through early
afternoon, and while most areas will remain dry during this
time, there could still be a spotty shower here or there.

Meanwhile, we will be waiting for the main shortwave to move off
the front range of the Rockies, which will fire strong and
possibly severe storms this afternoon. The CAMs honestly provide
varying locations for the convective development this
afternoon, but the consensus seems to indicate the best severe
threat along and south of a line from Columbus, NE to Sioux
City, IA. There should be enough recovery time to allow the
atmosphere to destabilize before this happens, and when storms
develop, they could be quite strong with supercells possible,
with all modes of severe weather possible. SPC has placed the
area in a slight risk for severe storms, with a 15% chance of
wind and hail, and a 5% chance of for an isolated tornado. WPC
has also placed eastern NE and southwest IA in the area for
excessive heavy rainfall since this area will receive heavy
rainfall this morning. Again though, confidence is somewhat low
where the axis of storms develop. The severe storm threat could
begin by 4 pm and linger through midnight. Any storms that
develop will continue to push east and be east of the forecast
area by daybreak Sunday. Before the severe storms arrive late
this afternoon, high temperatures should the middle to upper
80s, and could even reach the lower 90s along the KS/NE border.

And then hot weather is expected to develop Sunday with mostly
sunny skies and high temperatures in the middle to upper 90s.
Combined with dewpoints in the upper 60s, this will create
afternoon heat index values from 98 to 103, and major heat risk.
These values are just below official heat advisory criteria, but
those with outdoor plans should plan accordingly and stay well
hydrated with water and seek the shade whenever possible.
Southerly winds at 15 to 25 mph will help, but it will be the
hottest day of the year so far.

Storm chances come again Sunday night, mainly north of
Interstate 80, with a marginal risk of both severe storms and
excessive heavy rainfall.

Monday brings continued small storm chances north of I80, but
realistically, it could even be north of our forecast area. It
will be another hot day with high temperatures once again in
the lower to middle 90s, and heat index values 97 to 102. Due to
the prolonged heat, the heat risk will remain elevated, but
again, heat index values remain just below heat advisory
criteria. And rain chances continue north of I80 Monday night,
but again, based on newer models, any storms could also be
north of the area.

Another front moves into the region on Tuesday, which brings
more thunderstorms, and another chance for severe storms along
with heavy rainfall. And storm chances continue every day for
the remainder of the week. Highs Tuesday in the upper 80s to
lower 90s, but that front could bring cooler temperatures in the
upper 70s to upper 80s for Wednesday, but warming back up to the
upper 80s to lower 90s again by the end of the week.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 557 AM CDT Sat Jun 15 2024

Strongest of convection now east of TAF sites and continuing in
that direction through the day. Trailing stratiform showers are
already ending on the western edge of the CWA and those showers
will end by about 15Z in Omaha and earlier at LNK and OFK. Some
VFR cigs are also trailing the convection and it, too, should
wrap up by about noon.

Due to the level of uncertainty in this eve`s convection, have
not included in TAFs as model guidance is especially disparate
in time and space details. Will likely include some evening
timing with next TAF issuance.


&&

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

&&

$$

DISCUSSION...DeWald
AVIATION...Nicolaisen