770
FXUS64 KTSA 170538
AFDTSA

Area Forecast Discussion
National Weather Service Tulsa OK
1238 AM CDT Fri May 17 2024

...New AVIATION...

.SHORT TERM...
(The rest of tonight)
Issued at 941 PM CDT Thu May 16 2024

As of mid evening...a lead vort max to the parent low pressure
system...currently centered over far West Texas...continued to
move east northeast across far Eastern Texas. In response...the
majority of the associated precip to the lead vort max had
remained south and east of the CWA this evening. A few showers
remained in Northwest Arkansas...otherwise the majority of the CWA
was just partly to mostly cloudy. Underneath the clouds...temps
were in the 60s to low 70s with relative humidity values generally
greater than 85 percent.

Will continue to carry slight to low end chance showers/storms
for much of the CWA overnight as the upper low continues to
approach the region....though not anticipating a lot of storm
coverage. The greater potential overnight will be the development
of patchy/areas of fog across the CWA with light winds and all
the low level moisture already in place. Temps tonight should cool
slightly as dewpoints hold in the upper 50s to mid 60s. Forecast
low temps in the 60s should be common for most locations tonight.

Thus...for the evening update...have adjusted PoP/Wx grids based
on the mentioned above and tweaked the hourly rate of cooling
across the CWA tonight. Also added a mention of fog across the CWA
overnight tonight into Friday morning. Visibility should improve
through the morning hours...though shower/storm chances increase
with the low pressure system moving into the region.

&&

.LONG TERM...
(Friday through Thursday)
Issued at 126 PM CDT Thu May 16 2024

The upper level low will move overhead on Friday as an open wave.
Shear profiles will be poor, but the cooling upper levels and good
MUCAPE of 1000-2000 J/kg will promote pop up showers and
thunderstorms, especially with any sun breaks. The main hazards
would be brief heavy rain, gusty wind, small hail, and lightning.
By Friday evening the upper level low will be east and lingering
precipitation should be on the way out.

Much warmer temperatures are expected Saturday-Monday as the upper
level ridge builds overhead. Temperatures will climb into the mid to
upper 80s. Considering that there should be decent low level
moisture with dew points in the mid 60s to low 70s, the heat index
will likely climb into the low 90s in spots (especially Sun-Mon),
making it feel a bit more like summer.

As early as Sunday, the influence of a building western USA trough
will begin to be felt across the area as a weak shortwave passes
just to the north of the area. With decent instability and shear,
but marginal forcing, it may be just enough to initiate a few
showers and storms near the KS border Sunday evening. The upper
level low will then pivot across the northern Plains Tuesday,
pushing a cold front through the forecast area. Considering ample
instability, moisture, and lift it is likely that showers and
thunderstorms will break out along the cold front. Upper level
flow will be anomalously strong with a powerful subtropical jet
nosing into the region Tuesday as the cold frontal forcing
arrives. Accordingly, severe thunderstorms appear to be possible
if not probable, though specific details are scarce given the lead
time and model uncertainties with the event. Ensemble guidance
suggests the best chance of stormy weather would be across the
southeast half of the area at this time, but models are often too
aggressive with their eastward motion of fronts this time of year,
so we will continue to need to watch this potential.

Wednesday will likely be quiet behind the system from Tuesday,
assuming current guidance holds, but another low moving into the
western US and then ejecting eastwards will increase rain/thunder
chances again Thursday-Friday next week. As confidence in timing
is low, mainly kept 15-30% PoPs each evening during this period.

&&

.AVIATION...
(06Z TAFS)
Issued at 1237 AM CDT Fri May 17 2024

Areas of fog may result in reduced visibilities and ceilings
through mid morning Friday, otherwise mainly VFR conditions will
prevail. A few showers and thunderstorms will be possible Friday
afternoon, with the northwest Arkansas sites most likely to be
impacted.

&&

.PRELIMINARY POINT TEMPS/POPS...
TUL   79  61  85  64 /  20  10   0   0
FSM   79  63  84  64 /  60  30  10   0
MLC   77  60  85  64 /  40  20  10   0
BVO   78  57  85  60 /  20  10   0   0
FYV   76  57  83  60 /  60  30  10   0
BYV   74  58  81  60 /  60  30  20   0
MKO   76  61  84  62 /  40  20  10   0
MIO   77  58  83  61 /  30  10  10   0
F10   77  60  84  63 /  40  10  10   0
HHW   77  62  83  65 /  40  20  10   0

&&

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

$$

SHORT TERM...20
LONG TERM....06
AVIATION...05