809
FXUS63 KOAX 031025
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
525 AM CDT Thu Jul 3 2025

.KEY MESSAGES...

- Mostly sunny skies expected for today with warm and breezy conditions.
  Highs reach the low to mid 90s.

- Shower and storm chances return Friday evening through
  Saturday. PoPs peak at 50-65% Friday evening across northeast
  Nebraska and move east throughout the day Saturday. Some
  storms may be strong to severe Friday evening.

- Brief break in showers and storms Sunday but active pattern
  with 20-30% shower and storm chances continues into next week.

&&

.DISCUSSION...
Issued at 300 AM CDT Thu Jul 3 2025

.SHORT TERM.../Today through Friday Night/

Quiet conditions are observed across OAX early this morning with 8z
objective analysis showing the H5 ridge sitting over much of the
Central Plains. Earlier this morning, 5z KOAX and KFSD radar imagery
showed a few elevated thunderstorms just north of Knox and Cedar
counties. This activity appeared to have formed along a zone of weak
850 mb warm air advection, and with the best deep moisture
convergence observed just north and east of the forecast area,
expecting most of this activity to stay away from our CWA early this
morning.

Mostly sunny skies are expected for today as highs reach the low to
mid 90s. Far northern portions of the forecast area near the South
Dakota and Nebraska border could still see highs reach the upper
90s, and with dew points in the upper 60s to near 70F, heat indices
may briefly hit the 100F mark in the afternoon. H5 ridging should
largely suppress PoP chances, but a few CAMs try to generate widely
scattered pop up showers this afternoon. Confidence on this
occurring is very low at this time due to the lack of forcing
seen from model guidance, so have kept forecast dry.

A shortwave is expected to travel along the western periphery
of the ridge near the Colorado/Wyoming area throughout the day
today helping induce a sfc low. The sfc low will tighten the
pressure gradient resulting in breezy southerly winds especially
over northeast Nebraska. Winds will ease slightly tonight with
lows in the upper 60s to low 70s.

Friday will see the H5 shortwave amplify and deepen as it travels
east toward the Dakotas and central Nebraska. The sfc low will race
northeastward, dragging along a sfc trof which stalls across much of
central Nebraska by midday. Will again see breezy southerly winds
across much of the forecast area resulting from the pressure
gradient tightening. CAM guidance for this forecast package
develops an MCS looking feature along the sfc trof Friday
afternoon primarily over central Nebraska, while for eastern
Nebraska and western Iowa, CAMs generate widely scattered pop up
showers and storms. Soundings show some weak capping across the
forecast area which may help limit afternoon convective
development. As we head into the evening hours, the convective
line will first enter northeast Nebraska sometime around 7 pm
and then track across the rest of eastern Nebraska and western
Iowa overnight. CAM guidance still shows subtle differences
regarding timing and placement of the feature, so those with any
outdoor holiday plans should stay tuned to the forecast. PoP
chances increase from west to east, peaking Friday evening at
50-65% across northeast Nebraska.

Regarding severe potential, model guidance and soundings show around
1,500 J/kg of skinny MUCAPE in the afternoon and evening hours, but
once again, bulk shear remains the limiting factor with values at 20
to 25 kts. So, an isolated strong or severe storm with some hail or
wind is a possibility with this activity. The SPC currently has a
marginal risk of severe weather across portions of northeast
Nebraska for Friday. The WPC has also issued a marginal risk of
excessive rainfall across much of eastern Nebraska and western Iowa
as storms are still forecast to be in an environment with PWATs
around 2 inches and favorable warm cloud depths.

Highs for Friday will be in the upper 80s to low 90s, but will
ultimately be a function of the how much cloud cover overspreads the
area ahead of the disturbance. Despite heat indices in the low to
mid 90s, dew points in the upper 60s to low 70s will result in a
humid, uncomfortable airmass. Lows cool to the upper 60s to low 70s.

.LONG TERM.../Saturday through Wednesday/

The line of convection will continue pushing east early Saturday
morning along the sfc trof with PoPs peaking at 50-70%. Lingering
showers and storms continue Saturday afternoon and evening (15-30%
chance) as forcing from the mid level shortwave and sfc trof linger
in the area. Sunday will see another H5 shortwave skirt through some
zonal flow aloft over Nebraska, but a sfc high across the Dakotas
may dip slightly southeastward and help suppress PoP chances: the
NBM extended currently shows dry conditions for the majority of the
forecast area by Sunday afternoon.

By late Sunday into Monday, the H5 pattern shows another ridge
building and amplifying across the southwest US with much of the
Central and Northern Plains experiencing northwesterly flow aloft
for the remainder of the week. Several shortwave disturbances appear
embedded within this flow and has led to continued 20-30% chances
for showers and storms. Some low end severe threat (<5% chance) is
still indicated by much of the GEFS and Euro based severe
probability outlooks.

Aside from a slight cool down on Sunday (low to mid 80s),
temperatures in the extended will remain warm with highs in the
upper 80s to low 90s.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 523 AM CDT Thu Jul 3 2025

VFR conditions expected to prevail for this TAF cycle. Terminals
will see some gusty southerly winds again after 17z and should
subside by 00 or 01z.

1023z KOAX radar imagery shows an area of weak showers and
storms north of KSUX. Current thinking is that this activity
will stay well north of KOMA and dissipate within the next few
hours with only some FEW or SCT remnant clouds around 15-25kft.

&&

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

&&

$$

DISCUSSION...Castillo
AVIATION...Castillo