725
FXUS63 KOAX 281026
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
526 AM CDT Sat Jun 28 2025

.KEY MESSAGES...

- A 30-40% chance of storms exists primarily over northeast
  Nebraska after 7 pm. Some storms may be strong to severe with
  large hail and damaging winds.

- Showers and storms linger Sunday morning, with redevelopment
  likely (50-70% chance) in the afternoon and evening hours.
  Once again, a few storms could be strong to severe, and heavy
  rainfall may also occur.

- Dry conditions expected for Monday. 20-40% PoPs return late Tuesday
  into Wednesday and again Thursday into Friday. Temperatures
  cool slightly Monday before warming to the low to mid 90s by
  the end of the week.

&&

.DISCUSSION...
Issued at 342 AM CDT Sat Jun 28 2025

.SHORT TERM.../Today through Sunday Night/

Decaying MCS continues to progress just northeast of the forecast
area early this morning, with GOES-19 satellite imagery showing only
remnant clouds from the feature across northeast Nebraska and mostly
clear skies elsewhere. 8z RAP objective analysis shows the 500 mb
shortwave which provided some of the forcing for the
aforementioned convective complex skirting across the eastern
Dakotas, Nebraska, western Minnesota, and Iowa, while the next
approaching shortwave is already developing out over Wyoming.
Meanwhile at the sfc, a 1002 mb low is observed across eastern
Wyoming, southwestern South Dakota, and the Nebraska Panhandle.
8z METARs show temperatures in the upper 60s to mid 70s across
most of the forecast area.

Quiet conditions are expected for at least the morning and early
afternoon today with mostly sunny skies. Highs today will reach the
low to mid 90s areawide, and with dew point temperatures in the
upper 60s to near 70F, may see a few areas have heat indices reach
the upper 90s to near 100F for a few hours in the afternoon. Winds
will be breezy today from the south, owing to a tightening pressure
gradient from the sfc low feature. With the sfc low and mid level
wave moving to the northeast into central South Dakota throughout
the day today, a cold front will progress to the east into central
Nebraska. Ahead of the frontal boundary, will see moisture and 2,000
to 3,000 J/kg of MLCAPE pool within the warm sector of the low.
BUFKIT soundings show much of this instability being capped by a
warm layer aloft, however. Shear remains pretty weak within the
column, around 20 to 25 kts. With the front and shortwave providing
some weak lift, could see some scattered showers and storms along
the front, mainly after 23z today.

CAM solutions remain pretty widespread for this forecast package.
The NAM 4km Nest and NSSL WRF show convection firing along the sfc
boundary around 23z over north central Nebraska, eventually
congealing into an MCS and spreading into portions of northeast
Nebraska before taking a turn south and affecting far western
portions of our forecast area into the early morning hours Sunday.
Meanwhile, the HRRR keeps the vast majority of our forecast area dry
until about 2 or 3z when convection fires along the boundary,
entering far northwestern portions of the forecast area but
dissipating into showers early Sunday morning. And finally, the
HiRes FV3 and ARW indicate dry conditions across the entirety
of the CWA. Given the wide range in solutions, have kept PoPs at
30 to 40% this evening primarily across northeast Nebraska with
15-20% PoPs near our shared border with the Hastings forecast
office. Some of the storms may become strong to severe, with
large hail and damaging wind gusts the main threats. This has
prompted the SPC to issue a Slight Risk of severe weather for
portions of northeast Nebraska.

Showers and storms will linger across the forecast area Sunday
morning as the front pushes farther east southeast toward the
Missouri River valley. Of interest is how the HRRR picks up on a
subtle little line of convection Sunday morning over far eastern
Nebraska into western Iowa, most likely forced by the nose of a low
level jet. Redevelopment of storms is anticipated again along the
front in the afternoon and evening hours, some of which could again
become strong to severe. A Marginal Risk of severe weather exists
across a vast portion of Nebraska and western Iowa for Sunday. Model
soundings show an impressive amount of energy available, but
lingering clouds from previous convection could hamper how much of
this will be available for convection to use. The best shear also
appears to be offset from where the best instability will be. CAM
guidance again fires convection along the front during the
afternoon, but in varying locations. Have kept 50 to 70% PoPs
generally after 18z along the frontal boundary area.

Storms on Sunday may produce efficient rainfall, given the favorable
warm cloud depths and PWATs in the column being around 1.75 inches
or greater at times. As a result, a Marginal Risk of excessive
rainfall exists across eastern Nebraska and western Iowa. Highs
Sunday will largely be a function of cloud cover and the boundary
location, with areas behind the front (primarily northeast Nebraska)
seeing highs in the mid 80s, while elsewhere will see highs reach
the low to mid 90s. Lows Sunday night will be in the low to mid 60s
areawide.

.LONG TERM.../Monday through Friday/

PoPs linger early Monday morning before clearing out later in the
day as the sfc front pushes east into eastern Iowa. Aloft, may see a
shortwave clip the forecast area, but current thinking is that we
will remain dry given a sfc high moves over most of the Northern
Plains region.

500 mb ridging over the southern US will hold for a vast portion of
the long term forecast period with a trof out over the
California/western CONUS area. Shortwaves will ride the ridge, the
first of which is late Tuesday into Wednesday, resulting in the NBM
bringing back 20 to 40% PoP chances for those respective days. By
Thursday into Friday, another wave approaches the forecast area
resulting in widespread 20 to 40% PoPs. Machine learning
guidance shows low end severe probs (<5%) with this activity at
this time.

Highs Monday will be slightly cooler behind the front, reaching the
mid to upper 80s. A subtle warming trend though is observed
throughout the week with highs by Friday reaching the low to mid 90s
areawide.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 525 AM CDT Sat Jun 28 2025

VFR conditions expected for this TAF cycle. Main concern will be
gusty southerly winds after 16z lasting until about 00 or 01z.

A line of scattered showers and thunderstorms may develop after
00z and enter northeast Nebraska. Model guidance continues to
give varied solutions on placement of this line, with even some
guidance not developing anything until very late in the TAF
period. Storm chances are currently less than 50%, so have not
included any mentions for this TAF issuance at KOFK. Expect
further refinements and adjustments with future TAF issuances.
If storms develop, they could be strong to severe with large
hail and damaging wind gusts.

&&

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

&&

$$

DISCUSSION...Castillo
AVIATION...Castillo