111
FXUS64 KTSA 231739
AFDTSA

Area Forecast Discussion
National Weather Service Tulsa OK
1239 PM CDT Mon Sep 23 2024

...New AVIATION...

.SHORT TERM...
(The rest of today)
Issued at 1057 AM CDT Mon Sep 23 2024

Scattered showers continue to develop and stream in from the southwest
across the forecast area this morning as an upper-level trough
works its way eastward across the Plains. Visible satellite
imagery shows thick stratus clouds blanketing the region ahead of
the upper-level trough axis. Current temperatures range from near
60 degrees along the OK/KS border to near 70 degrees in far
southeast OK and west-central AR. As diurnal heating progresses
and more mixing gets going into this afternoon, clouds should lift
some and instability is expected to increase slightly,
particularly across far southeast OK and into northwest AR. Additional
showers and perhaps a few thunderstorms are likely to develop
this afternoon, highest chances across far eastern OK and
northwest AR. Unseasonably cool temperatures will persist today,
with highs reaching the low-mid 70s for most locations.

Cloud cover and precipitation should clear west-to-east this
afternoon as the upper trough axis approaches. Made some minor
adjustments to temperatures, increasing them a degree or two along
and west of Highway 75 in OK as cloud cover should become more
broken to scattered by mid-late afternoon. Further adjustments to
temperatures may be needed if cloud cover is able to break apart
quicker. Also made a few adjustments to the PoPs/Wx through this
afternoon, lowering the chance of thunder from the earlier
forecast.

Mejia

&&

.LONG TERM...
(Tonight through Sunday)
Issued at 242 AM CDT Mon Sep 23 2024

With clouds and precipitation clearing the area, temperatures will
cool significantly into Tuesday morning. Low temperatures will range
from the low 50s in the northwest to near 60 in the southeast.
Temperatures will rebound during the day Tuesday, but with
another upper level low diving into the region, any break in storm
activity will be short lived. Rain chances will increase Tuesday
afternoon through Wednesday morning, though totals will mostly be
minimal.

There has been considerable uncertainty the last several days with
regards to the pattern during the late week period and onwards due
to large variation in how models handle this upper level low (as
well as the possible entrainment of tropical moisture). Although
the specifics are still not known, the general picture is becoming
a bit more clear. For Wednesday through Thursday the upper level
low will hang out somewhere east of the area. Some guidance such
as the latest ECMWF keeps the upper level low over AR, while other
guidance such as the GFS or CMC are a bit further east. In either
case the upper level low is expected to then retrograde westwards
towards the area Friday-Saturday bringing increased rain and
thunder chances.

Ensemble cluster analysis suggests that the most likely outcome (50-
60 % chance) is for the upper level low to remain relatively
closer to the forecast area. The EPS mean shows this as a rather
anomalous pattern with unusually low surface pressure and mid
level heights for this time of year as well as anomalously strong
mid level east to northeast flow around the low pressure area.
Additionally, moisture levels will be above the 90th percentile.
This pattern would increase the probability for areas of moderate
to possibly heavy rainfall next Friday-Saturday. Pops and
forecast precipitation were increased for this time frame. With
the upper level low hanging over or near the area through next
weekend, temperatures will remain near to below normal with at
least a slight chance of rain each day.

&&

.AVIATION...
(18Z TAFS)
Issued at 1239 PM CDT Mon Sep 23 2024

Latest surface observations show a mixture of IFR/MVFR ceilings around
the area. Scattered showers and isolated thunderstorms will
persist over the next few hours, with chances ending west-to-east
through the afternoon and into early this evening. Likewise,
ceilings should gradually lift and break apart west-to-east
later this afternoon, with prevailing VFR conditions at all OK
terminals by 00z. MVFR ceilings are expected to linger across the
NW AR terminals through at least midnight. Guidance continues to
signal light patchy fog developing early Tuesday morning,
particularly across NW AR. Cannot rule out a brief period of
reduced vsbys at the OK terminals as well, but confidence was not
high enough to include in the TAFs at this time. Winds remain
light though the period, turning more W/WNW by late morning
Tuesday.

Mejia

&&

.PRELIMINARY POINT TEMPS/POPS...
TUL   57  81  57  80 /   0  10  20  10
FSM   64  84  61  83 /  20   0  40  10
MLC   58  84  58  83 /   0  10  50  10
BVO   53  80  52  82 /   0  10  10  10
FYV   58  78  54  79 /  30  10  20  20
BYV   59  76  55  78 /  40  10  10  20
MKO   56  79  57  80 /   0  10  30  10
MIO   56  76  53  78 /  20  10  10  10
F10   54  81  56  80 /   0  10  30  10
HHW   61  86  61  83 /   0   0  40  10

&&

.TSA WATCHES/WARNINGS/ADVISORIES...
OK...None.
AR...None.
&&

$$

SHORT TERM...67
LONG TERM....06
AVIATION...67