447
FXUS64 KOUN 061701
AFDOUN

Area Forecast Discussion
National Weather Service Norman OK
1201 PM CDT Mon May 6 2024

...New SHORT TERM...

.SHORT TERM...
(This evening through Tuesday)
Issued at 1200 PM CDT Mon May 6 2024

**SIGNIFICANT SEVERE WEATHER EXPECTED TODAY AND TONIGHT**

SUMMARY - All the ingredients still appear to be coming together for
a significant severe event as a potent shortwave trough ejects into
the plains later this afternoon. Ahead of this feature, moisture
advection is underway with low stratus seen across much of the
forecast area. Moisture advection will continue through the day,
contributing to strong instability by peak daytime heating. Wind
fields will also be strong, with large, curved hodographs seen in
model soundings across much of the area, especially towards and
after 00z as the low level jet ramps up.

With high confidence that the necessary ingredients will be there,
the biggest question mark remaining is storm coverage and how far
south storms will develop as the greatest forcing from the trough
passes largely to our north, i.e. will we see widespread
thunderstorm development or just a couple scattered (likely intense)
storms. For now, it appears storm coverage will be greatest closer
to the Kansas border, tapering to isolated near and south of I-40.
Storm mode is a secondary uncertainty, with several of the CAMs
suggesting a faster transition to a more linear mode across northern
Oklahoma, which could decrease the hail threat but increase the wind
threat (lower probability scenario for now). Tornadoes will be
possible with either storm mode.

SEVERE HAZARDS - The overall environment will support large to giant
hail (>3" in diameter) and significant, long-track tornadoes with
any discrete supercell that develops. Damaging wind gusts will also
be a concern, especially if we see high-precipitation supercells
and/or a transition to more linear modes later on. The environment
will remain supportive of severe weather, including tornadoes, well
after dark. In fact, the tornado environment will only become more
favorable after dark as low-level wind shear maximizes and influx of
a moist and unstable airmass continues. Additionally, thunderstorms
will be capable of very heavy rainfall which could lead to localized
flooding, especially in areas that have seen excessive rainfall
recently.

STORM MOTION - Storm motion will generally be northeast or east-
northeast at 40-50 mph, with right-moving supercells moving east or
east-northeast at 30-35 mph.

TIMING - Convective development is expected first across northwest
and/or western OK by 1-4 PM as the initial forcing with the
shortwave impinges on the dryline. These storms will continue east-
northeastward into north-central OK by early evening (6pm to
midnight). There is a lower risk for more isolated thunderstorms
developing out ahead of the main line in northern/central OK between
4-8 PM. The threat could linger past midnight across
eastern/southeastern parts of the area, but uncertainty is greater
here on if we will see storms develop this far south and east.

Bottom line: Not everyone will see a storm today, but any storm that
develops will be capable of significant severe weather and should be
taken seriously this afternoon through late this evening!

Day/Ware

&&

.LONG TERM...
(Tuesday through Sunday)
Issued at 203 AM CDT Mon May 6 2024

Storms will be out of our area before sunrise Tuesday morning, with
mostly sunny skies expected through the day with highs in the low
80s. Models show another shortwave moving into the plains on
Wednesday as moisture attempts to move back northward into our
southeast counties. As of now the flow is expected to veer across
much of our area through the day Wednesday, which should push the
better moisture eastward and confine any thunderstorm chances to our
eastern/southeastern counties. Instability and shear will support
severe weather with these storms, with large hail and damaging
wind gusts the main threat.

After Wednesday the synoptic pattern appears to transition to one
much less favorable for severe weather, with high pressure to our
north confining the deeper moisture well to our south into the
weekend. This should finally give our area a bit of a break,
although we will not completely dry out as rain chances (non-severe)
return to the area Saturday into Sunday.

Ware

&&

.AVIATION...
(12Z TAFS)
Issued at 637 AM CDT Mon May 6 2024

Reduced visibilities due to fog and very low ceilings will
maintain LIFR conditions at most of our terminals at least through
14Z, after which rising stratus will improve conditions at least
to MVFR and returning to VFR conditions after 21Z. However,
expecting severe thunderstorms after 00Z could affect most of our
terminals and reducing them back to at least MVFR conditions at
least until 06Z. Surface winds will be gusty out of the south at
10-20 kts with 25-30 kt gusts. A Pacific front & dryline will
start pushing through after 00Z and start veering winds out of the
west behind the boundary with west to west-northwest winds by the
end of this forecast across our terminals.

&&

.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK  79  54  81  64 /  40  50   0   0
Hobart OK         85  51  83  57 /  30  20   0   0
Wichita Falls TX  84  55  84  66 /  20  20   0   0
Gage OK           86  49  85  51 /  20  10   0   0
Ponca City OK     80  51  81  58 /  60  80   0  10
Durant OK         82  67  85  68 /  20  30   0  10

&&

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

$$

SHORT TERM...14
LONG TERM....08
AVIATION...68