033
FXUS64 KTSA 221708
AFDTSA

Area Forecast Discussion
National Weather Service Tulsa OK
1208 PM CDT Sun Sep 22 2024

...New AVIATION...

.UPDATE...
Issued at 1112 AM CDT Sun Sep 22 2024

Batch of showers with isolated thunderstorm potential is finally
beginning to move northeastward into parts of northeast Oklahoma
just north of I-44 and west of Highway 75 late this morning. The
expectation is that coverage will remain on the low to medium side
through the daylight hours, with coverage and intensity picking up
during the afternoon given CAM trends. POP adjustments through the
morning have been made to adjust the maximum values southward a
bit given the current radar and also in the afternoon to lower
them a bit - leveraging the short-term blend - given expected
lower coverage. Will also keep any thunderstorm mention isolated
until mid to late afternoon. Overall severe weather threat this
afternoon/evening remains limited, with forecast instability and
already available shear supportive of an isolated strong to severe
storm or two later today. Updated forecast out, with potential for
further adjustments into early afternoon depending on
observational trends.

22

&&

.SHORT TERM...
(Today)
Issued at 220 AM CDT Sun Sep 22 2024

Widespread rain with isolated embedded thunderstorms are noted from
north-central OK up into southeast KS this morning. An outflow
boundary has pushed to near the I-44 corridor with evidence of
gravity waves northwest of it. Additional reinforcing outflow
boundaries are also present further to the west. So far there has
been limited precipitation within the forecast area, but both
observational trends and CAMs suggest the axis of precipitation
will drift east the next few hours resulting in increasing rain
chances for portions of northeast OK near the KS border.

CAM guidance indicates a slow progression of showers and storms
during most of the morning hours today, resulting in a rather
sharp temperature gradient from northwest to southeast. Small
differences in how quickly the precipitation moves will have a
large difference in high temperatures. Areas that are well to the
south of the main precipitation band are expected to still reach
the lower 90s this afternoon.

By mid to late afternoon the surface cold front will pick up speed
and push through the area bringing much cooler temperatures and a
gusty northwesterly wind. Additionally, shower and storm chances
will increase for the entire forecast area during this period. With
lower atmospheric moisture levels near the 97-99% percentile for
this time of year, a few of the storms could produce locally
heavy rainfall. A few factors will mitigate the severe weather
threat with more of a messy storm mode expected, but there will be
sufficient shear and instability to promote a few strong to
severe storms, mainly due to wind.

&&

.LONG TERM...
(Tonight through Saturday)
Issued at 220 AM CDT Sun Sep 22 2024

Overnight tonight the mid level trough axis will approach the
area. This, with colder mid to upper level air, will promote
additional rain and thunderstorm activity. Storm total
precipitation will mostly be below one inch, but localized totals
could be higher under any heavy thunderstorms. Precipitation will
mostly become confined to Arkansas by Monday afternoon and out of
the area completely by the late evening. Model guidance shows
considerable spread on Monday with some guidance holding onto
clouds and showers longer, with highs perhaps as low as the upper
60s. Other guidance that is quicker to move the rain out allows
for temperatures in the upper 70s. Opted to split the difference
for now with highs mainly in the low to mid 70s. Low temperatures
will fall into the low 50s in the north Tuesday morning, with
upper 50s in the south.

A trailing shortwave trough will dig into the rear of the previously
mentioned storm system as it tries to move east during the midweek
period. Model guidance continues to show considerable uncertainty,
but confidence is increasing on a renewed chance of a few showers
Tuesday night into Wednesday, especially for eastern OK. The upper
level low will probably settle just east of the area, keeping
temperatures below seasonal norms through at least late week.

Things become more interesting for the end of the week into the
weekend as a potential tropical system approaches the Gulf coast.
A small subset of ensemble guidance ingests some of the tropical
moisture into the closed low and wraps precipitation back into the
area. A larger subset keeps the tropical system too far east to
affect the area much, with varying degrees of ridging trying to
impinging on the area from the west. Overall, most of these
solutions would still keep temperatures near or below normal for
this time of year.

&&

.AVIATION...
(18Z TAFS)
Issued at 1208 AM CDT Sun Sep 22 2024

Aviation conditions are expected to deteriorate mid to late
afternoon into the overnight at all terminals, with widespread IFR
ceilings behind a cold front that will pass through the area and
expected shower and thunderstorm impacts. Multiple rounds of
showers and thunderstorms remain expected, beginning this
afternoon at TUL/RVS (given the storms approaching from central
OK) continuing into other TAF sites into early Monday morning. In
addition, expect a wind shift at FYV/ROG within the first hour or
so of the TAF period due to a pre-frontal boundary passage, which
sits between XNA and those 2 sites at present.

&&

.PRELIMINARY POINT TEMPS/POPS...
TUL   85  61  74  57 /  50  70  40   0
FSM   93  70  77  62 /  10  40  70  10
MLC   94  63  76  56 /  20  50  70   0
BVO   82  56  73  51 /  50  60  30   0
FYV   88  64  74  55 /  20  60  80  20
BYV   88  65  73  58 /  20  60  80  30
MKO   89  62  72  56 /  40  60  60  10
MIO   82  60  71  55 /  30  70  60  10
F10   90  61  74  54 /  40  60  60   0
HHW   92  69  80  60 /   0  20  60  10

&&

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

$$

SHORT TERM...06
LONG TERM....06
AVIATION...22