725 
FXUS64 KTSA 122344
AFDTSA

Area Forecast Discussion
National Weather Service Tulsa OK
644 PM CDT Thu Apr 12 2018

.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
Gusty southerly winds and few/scattered mid and high clouds should
remain common into the overnight hours tonight. Late tonight and
into Friday morning...MVFR ceilings look to develop and spread
across the CWA within the gusty winds ahead of a dryline 
approaching from the west. MVFR ceilings look to remain common
through the TAF period for Northwest Arkansas. Dryline looks to 
pass Eastern Oklahoma TAF sites Friday afternoon with clearing 
skies and continued gusty southwesterly winds. Small chances for 
showers/storms during the morning hours Friday over the CWA with 
increasing chances for Southeast Oklahoma and Northwest Arkansas 
Friday afternoon ahead of the dryline. Will continue with Prob30 
groups for timing.  


&&

.PREV DISCUSSION... /Issued 310 PM CDT Thu Apr 12 2018/ 

DISCUSSION...
Gusty south winds continue this afternoon as the Lee surface
cyclone continues to deepen. Fire weather conditions have been
tempered some by improved moisture, with surface dewpoints
rebounding to 55-60F and RH values remaining above 50 percent.
Exception is across parts of Osage/Pawnee counties where drier 
air resides and existing fires continue to be aggravated. The 
strong low-level jet will keep surface winds gusty into the 
overnight hours, and may need to extend the wind advisory for the 
remainder of the night.

A strong cap will remain in place through tonight, although still
expecting some elevated convection to develop late tonight into 
Friday morning as the persistent warm-air advection eventually 
erodes the cap. Followed the 12Z NAM fairly closely for the dry
line progression tomorrow afternoon, which offers a compromise
between the faster GFS and slower ECMWF. As such, quickly
deteriorating fire weather conditions are expected west of U.S. 75
later Friday afternoon, with RH values dipping to around 20 
percent along with gusty southwesterly winds. Will upgrade the 
existing Fire Weather Watch to a Red Flag Warning.

Convective evolution certainly isn't clear cut for tomorrow 
afternoon, with a few CAM solutions suggesting initial 
development as early as 18-19Z as the dry line moves into eastern 
OK. The bulk of the solutions, however, hold off on significant 
development until 21Z and beyond mainly east of U.S. 75. CAMs 
also suggest that the activity may initially be quite scattered, 
with storms eventually growing upscale as they exit our forecast 
area by mid-evening. Regardless, strongly sheared wind profiles 
and MU CAPE values exceeding 2000 J/KG will support strong/severe 
storms with all modes of severe weather possible.

Breezy and cool weather conditions will prevail through the
weekend in the wake of the frontal passage. Will likely need
freeze headlines for Sunday and Monday mornings as temps dip below
freezing for a few hours, especially north of I-40. Milder weather
expected for early next week with a weak cold front moving through
by Wednesday.

&&

.PRELIMINARY POINT TEMPS/POPS...
TUL   69  80  39  51 /  20  40  10  10 
FSM   64  78  45  56 /  20  60  50  10 
MLC   69  79  41  56 /  30  40  20   0 
BVO   69  82  39  50 /  20  40  10  10 
FYV   63  74  40  51 /  10  60  50  10 
BYV   63  74  44  51 /  10  60  60  10 
MKO   65  78  41  53 /  20  40  20  10 
MIO   66  79  39  49 /  20  50  30  10 
F10   67  79  40  53 /  20  30  10  10 
HHW   65  78  45  57 /  30  60  30   0 

&&

.TSA WATCHES/WARNINGS/ADVISORIES...
OK...Wind Advisory until 1 AM CDT Friday for OKZ054>071-073.

     Red Flag Warning from 1 PM to 10 PM CDT Friday for OKZ054-059-
     064-065.

AR...Wind Advisory until 1 AM CDT Friday for ARZ001-002-010-011.

&&

$$


AVIATION.....20