811
FXUS64 KTSA 230525
AFDTSA

Area Forecast Discussion
National Weather Service Tulsa OK
1225 AM CDT Thu May 23 2024

...New AVIATION...

.UPDATE...
Issued at 753 PM CDT Wed May 22 2024

The more recent runs of the HRRR and the 18Z EC suggest an
increase in storm coverage later on tonight from SE OK up into NW
AR. The non-HRRR CAMs are quiet for tonight, but don`t have the
shower activity that`s already popping up on radar there, and the
more aggressive storms across NE TX. With plenty of elevated to
near surface-based instability and deep layer shear, any storms
that develop will pose a severe weather threat. Despite the more
favorable near surface based moisture/instability in the lower AR
River valley, weak low level shear will limit the tornado threat.

Lacy

&&

.SHORT TERM...
(The rest of this afternoon )
Issued at 132 PM CDT Wed May 22 2024

A surface boundary is slowly working its way south across far
southeast OK. Thunderstorms, any of which could become severe,
will continue to develop at times through the remainder of the day
near and north of this boundary. All severe hazards will be
possible near the boundary, with hail being the primary hazard
north of the boundary. North of I-40, elevated storms may also
pop up at times. The severe threat will be lower, but not zero,
with marginally severe hail possible in any stronger storms. Areas
of heavy rainfall will occur with any storms, so the Flood Watch
for southeast OK and parts of west-central AR will continue
through the afternoon to account for this threat.

Overnight, scattered showers and storms will continue to develop at
times, especially for southeast OK and northwest AR. But
confidence is low on exact timing and strength as CAM guidance has
been inconsistent. The overall severe threat may trend down
somewhat tonight, but isolated severe storms are still possible.
Lows will range from the upper 50s to mid 60s most areas.

&&

.LONG TERM...
(Tonight through Wednesday)
Issued at 132 PM CDT Wed May 22 2024

The same general pattern will remain locked in through Saturday with
a deep trough across the northwest and a ridge in the southeast. As
shortwaves periodically rotate through they will bring lift and
enhanced wind shear over an exceptionally moist and unstable lower
atmosphere.

One such shortwave will move through Thursday. It is unclear whether
there will be sufficient low level convergence and lift to support
convective initiation, but the upper levels show good divergence as
the area will be in the left exit region of a jet. CAM guidance is
uncertain on timing and intensity of convection, but scattered
thunderstorms will likely develop. A few of the storms will become
severe with wind and hail being the more likely threats, though an
isolated tornado may also occur. A weak boundary moves through
Friday morning, and storms should continue at times through then.
Presumably storm coverage will decrease somewhat behind the
boundary, but with plenty of moisture and instability still in
place, storm activity can`t be ruled out. The best chance for
storms Friday will be over the higher terrain of eastern OK and
northwest AR. Highs will be below normal Thursday, generally in
the upper 70s to lower 80s, increasing to the low to mid 80s
Thursday.

A stronger shortwave and associated surface cold front will move in
Saturday. Overall this looks to be the most likely day for
widespread thunderstorms and severe weather within the forecast
period. The environment will support all severe hazards within
the stronger storms. Ridging builds in west of the area Sunday
into early next week. With decent northwest flow and plentiful low
level moisture and instability, the storm chance will not be
zero, though presumably the severe weather threat should be lower
than this week. Normally we see increase nocturnal MCS activity in
this type of pattern, which is also increasingly common heading
into June, so bumped up NBM pops a bit each day to mentionable to
account for this possibility.

&&

.AVIATION...
(06Z TAFS)
Issued at 1222 AM CDT Thu May 23 2024

Coverage of showers and thunderstorms expected overnight with
lowering ceilings, primarily in the MVFR category. Confidence
regarding finer details remains quite low through the period, but
in general, expect MVFR conditions to transition to VFR early to
mid afternoon. Additional thunderstorms are possible late this
afternoon and this evening, though timing and extent remain very
much in question.

&&

.PRELIMINARY POINT TEMPS/POPS...
TUL   68  84  62  86 /  40  20  10  30
FSM   69  87  69  88 /  60  20  30  20
MLC   68  86  66  87 /  40  20  20  20
BVO   64  82  56  85 /  40  20  10  30
FYV   65  83  61  85 /  60  30  30  30
BYV   65  83  61  84 /  50  30  30  30
MKO   67  84  63  86 /  50  20  20  30
MIO   66  80  59  83 /  50  30  10  30
F10   67  85  63  86 /  40  20  20  30
HHW   68  87  67  87 /  50  10  30  10

&&

.TSA WATCHES/WARNINGS/ADVISORIES...
OK...Flood Watch through this evening for OKZ049-053-072>076.

AR...Flood Watch through this evening for ARZ019-020-029.

&&

$$

SHORT TERM...06
LONG TERM....06
AVIATION...14