663 
FXUS64 KTSA 191755
AFDTSA

Area Forecast Discussion
National Weather Service Tulsa OK
1255 PM CDT Sun Apr 19 2020

.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.

The beginning of the TAF period will be quite busy for most
locations. Thunderstorms are expected to develop within the next
hour or 2 of writing. Storms are expected to impact southeast
Oklahoma and northwest Arkansas with associated TAF sites expected
to be affected. The TAF sites include KMLC and all of our NW AR
TAF sites. KTUL, KRVS,and KBVO, will likely not see thunderstorms
this afternoon given the latest guidance and limited instability 
but there continues to be a low chance for a brief shower. The 
strongest thunderstorms could be seen over KMLC and KFSM this 
afternoon with the main threat being large hail with severe wind 
gusts possible. Thunderstorms will quickly move out of the area by
early this evening. 

Tonight will feature clearing skies for most TAF sites and light
winds leading to VFR conditions through most of the night. Given 
that the soil is expected to moist from today's rains, areas of 
fog will be possible. Valleys and locations near bodies of water 
will see the greatest potential for fog late tonight into tomorrow
morning. Our NW AR TAF sites will likely see the best potential 
for lowered visibilites given light winds, mostly clear skies, and
short term guidance has been showing signal for the past several 
runs adding to confidence in the forecast. Our far NW AR TAF 
sites (excluding KFSM) will also see a greater likelihood of MVFR
to IFR ceilings late tonight into tomorrow morning as well. 




&&

.PREV DISCUSSION... /Issued 1019 AM CDT Sun Apr 19 2020/ 

..UPDATE...

DISCUSSION...

A couple of thunderstorms are ongoing across portions of Adair and
Washington (AR) counties this morning. These cells have pulsed up
a little, enough so to produce pea size hail near Tahlequah, but
over these thunderstorms are staying below severe limits which
should be the continued trend for at least the next few hours
given limited instability thanks to a thick stratus deck.

This afternoon will be a little more interesting. Strong to severe
storms will be possible for much of the area with the greatest
chances for severe weather located over southeast Oklahoma and
west-central Arkansas. This area will be closer to the low
pressure center and the attendant warm front. Locations along and
south of the warm front will see the best chances for severe
weather due to better shear (likely characterized by rotating
updrafts) and better instability. Pockets of clearing will be
possible across southeast Oklahoma this afternoon which could
locally elevate the severe threat. The question still remains, 
how far north will this warm front move? At the moment is appears 
the best answer to that question is points just to the south and 
southeast of a line extending from about McAlester to Fort Smith. 
Thunderstorms in the aforementioned region will be capable of 
producing golf ball size hail with a lower threat for damaging 
wind gusts. A warm front farther north would promote more surface 
based storms and thus a better chance for damaging wind gusts. 
Locations to the north of the aforementioned area will likely 
exhibit less instability and storms will likely be more elevated 
in nature. Regardless, a few supercells are expected this 
afternoon across parts of SE OK and W-central AR. 

Snider

&&

.PRELIMINARY POINT TEMPS/POPS...
TUL   46  75  49  75 /   0   0   0  10 
FSM   46  75  50  78 /  20   0   0  10 
MLC   48  74  51  78 /  10   0  10  10 
BVO   44  75  47  74 /   0  10   0   0 
FYV   44  72  48  74 /  20   0  10   0 
BYV   43  71  47  72 /  20  10  10   0 
MKO   44  72  49  75 /  10   0   0  10 
MIO   42  72  45  71 /   0  10  10   0 
F10   46  74  51  76 /  10   0  10  10 
HHW   51  73  53  77 /  10   0  10  10 

&&

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

$$


AVIATION.....21