648
FXUS64 KOUN 171105
AFDOUN

Area Forecast Discussion
National Weather Service Norman OK
605 AM CDT Tue Sep 17 2024

...New AVIATION...

.KEY MESSAGES...
Updated at 539 AM CDT Tue Sep 17 2024

    - Thunderstorms will approach western/northwest Oklahoma this
      evening, though they will likely be weakening as they
      arrive.

    - A few storms are expected along the dryline in western and
      northern parts of the area tomorrow, with a low risk of
      damaging winds.

    - Hotter through the rest of the week before a possible
      pattern flip over the weekend.

&&

.SHORT TERM...
(Today and tonight)
Issued at 239 AM CDT Tue Sep 17 2024

Near-term forecast will largely be quiet, with light easterly winds
and clear skies for the rest of the night. Slightly higher moisture
will advect in from eastern Oklahoma overnight, which will increase
the potential for at least bands of stratus/locally favored
radiation fog in the eastern part of our forecast area around
daybreak.

Otherwise, another mostly sunny afternoon is expected today with
winds beginning to shift from east-southeasterly to more south-
southeasterly. Highs will reach from the upper 80s in the eastern
part of the area to the mid-90s out west.

Precipitation chances look very low at least through about 7 pm.
Toward the evening, a trough will eject into the central Plains,
with at least glancing height falls reaching the southern High
Plains. This should touch off a round of robust convection in the
Raton Mesa which will consolidate and move eastward early tonight.
How much we`re actually impacted by those storms is an open
question - the wave lifts pretty far off to the north and
convection-allowing guidance weakens storms dramatically as they
approach northwest Oklahoma around midnight. However, it`s worth
noting that that guidance (which has performed downright poorly
over the last several days) shows the same signal for increasing
instability late in the night as the LLJ begins to veer that we`ve
seen in recent nights. All told, the chance for rain/storms
tonight still seems to be low, but chances will be highest across
northwest Oklahoma. Low temperatures will be higher as return flow
starts to bring in modified Gulf air.

Meister

&&

.LONG TERM...
(Wednesday through Monday)
Issued at 239 AM CDT Tue Sep 17 2024

Return flow continues on Wednesday as broad southwest flow begins to
finally erode at the northwest side of the Texas ridge. The dryline
will mix eastward throughout the day toward the Caprock. Multiple
pieces of guidance (notably the NAM 3km, NSSL WRF, MPAS, and RRFS)
show storm development along and just east of the Caprock from the
eastern Texas panhandle northeastward toward southern Kansas. Mid-
level flow will be modest, but veering in the lower levels and
abundant upper-level wind shear could very well promote some
transient supercell structures early in the storms` lifecycles. Hail
to the size of quarters will be possible early on, but the primary
concern with storms will likely be damaging wind gusts as well-mixed
boundary layers and dry mid-levels combine for about 1,600 DCAPE.
This activity should start to wane in the evening and by early in
the overnight. Highs on Wednesday will be warmer again, reaching the
low to upper 90s across the area.

Right now our official forecast suggests little-to-no chances for
storms on Thursday. However, with the dryline mixing eastward again
and NAM soundings suggesting an uncapped 1000-1500 MLCAPE just east
of the dryline, this forecaster does not share the confidence in dry
weather that the National Blend of Models holds. The period
encompassing Thursday afternoon and evening in western and northern
parts of the CWA will be watched as a potential forecasting target
of opportunity. Otherwise, expect another step up in temperatures
during the day on Thursday, with all locations seeing mid-90s to
around 100 for the highs.

After another hot day on Friday, attention will turn to the weekend
as a potential period of more active weather. This will be driven by
an upper-level low that right now is subjected to a fair amount of
model uncertainty - some guidance tries to eject it well to our
north, while other guidance would keep it much closer to us on
Saturday. While details are thus somewhat unclear, it does appear as
though late Saturday night may have to be watched as a particular
period of note, with some models showing a Pacific front sweeping
west to east and an unstable environment in front of it.

Meister

&&

.AVIATION...
(12Z TAFS)
Issued at 539 AM CDT Tue Sep 17 2024

Area of mainly MVFR ceilings will make a run at the I-35 corridor
this morning before retreating back to the east by late morning.
Have included a tempo at SWO/OKC and prevailing at DUA with a
period of IFR this morning. Otherwise, mainly VFR conditions
through the day today with southeast winds. Some gusts across the
west could exceed 20kts. There is a chance for a few shower/storms
to impact WWR after 05Z this evening.

&&

.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK  88  68  92  73 /   0   0   0  10
Hobart OK         94  69  97  74 /   0  10   0  20
Wichita Falls TX  95  70  98  74 /   0   0   0   0
Gage OK           94  67  96  70 /   0  30  20  20
Ponca City OK     90  67  93  72 /   0   0  10  10
Durant OK         88  68  93  72 /   0   0   0   0

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...None.
TX...None.
&&

$$

SHORT TERM...04
LONG TERM....04
AVIATION...30