290
FXUS64 KTSA 192114
AFDTSA

Area Forecast Discussion
National Weather Service Tulsa OK
414 PM CDT Sat Aug 19 2017

.DISCUSSION...
A few thunderstorms continue to develop to the north in Kansas near
an old frontal boundary.  These storms will track southeast and could
reach northeast Oklahoma and northwest Arkansas this evening. In addition,
the Level of Free Convection is dropping to below 3000 feet in far northeast
Oklahoma.  The deep mixing from the strong heating could reach that level and
result in an isolated storm or two developing this evening.  Also, an isolated
storm or two may develop this evening in the terrain of northwest Arkansas.

Surface-based CAPE is very high, between 4000 and 5000 j/kg in northeast Oklahoma
and northwest Arkansas.  Weak deep-layer shear will limit hail potential, but
obviously a severe wind gust is likely with any strong cell.

Any storms this evening should weaken in the early night with loss of heating.  But
the southern extent of a weak isentropic lift zone may extend into far northeast
Oklahoma late tonight and early Sunday.  That could result in an isolate cell
developing.

With the low-level moist axis over the region on Sunday a few showers and storms
could occur at any time, most likely in the Afternoon and in the terrain of
northwest Arkansas.

Heat index values will peak around 105F from parts of northeast Oklahoma into
west-central Arkansas on Sunday.  The current advisory will drop this evening and
come back into effect in the above noted areas tomorrow.

Sunday night the low-level flow will increase some and this should promote a
storm complex or two in the central U.S. on Sunday night into early Monday.  Confidence
is very low on the placement.  This activity has implications for eclipse viewing on
Monday.  It will be important to monitor later forecasts if you plan to travel
to the path of totality.

A cold front is expected to cross the region on Tuesday and Tuesday night.  Widespread
shower and thunderstorm activity is expected to develop in the area on Tuesday afternoon
and spread south.  Locally heavy rains are likely in parts of the region.  This
front will push south into Texas, but likely not very far.

&&

.PRELIMINARY POINT TEMPS/POPS...
TUL   75  96  75  93 /  20  10  10  20
FSM   75  96  74  92 /  20  20  10  30
MLC   74  93  74  91 /  10  10   0  20
BVO   72  96  74  94 /  20  10  20  20
FYV   71  91  72  88 /  30  20  10  30
BYV   71  92  71  90 /  20  20  20  30
MKO   74  94  73  92 /  30  10  10  20
MIO   73  93  73  91 /  30  20  20  20
F10   73  95  73  93 /  10  10  10  20
HHW   75  92  75  90 /  10  10  10  20

&&

.TSA WATCHES/WARNINGS/ADVISORIES...
OK...Heat Advisory until 7 PM CDT this evening for OKZ049-053>076.

     Heat Advisory from noon to 9 PM CDT Sunday for OKZ054>057-
     059>061-064-067-070-072-076.

AR...Heat Advisory until 7 PM CDT this evening for ARZ019-020-029.

     Heat Advisory from noon to 9 PM CDT Sunday for ARZ019-020-029.

&&

$$

SHORT TERM...69
LONG TERM....08