257 FXUS64 KTSA 071136 AFDTSA Area Forecast Discussion National Weather Service Tulsa OK 536 AM CST Mon Jan 7 2019 .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG. MVFR ceilings and scattered showers will clear out of the northwest Arkansas sites by mid morning. VFR conditions will then prevail at all sites for the rest of the forecast period. Gusty south winds will shift to the southwest and gradually diminish later today and this evening. A cold front will shift the winds to the northwest late tonight. && .PREV DISCUSSION... /Issued 422 AM CST Mon Jan 7 2019/ DISCUSSION... Early this morning...a shortwave was pushing across the Central Plains with an associated surface low across Eastern Kansas. A cold front stretched from the surface low through Western Oklahoma into Southwest Texas. Ahead of this boundary...gusty southerly winds were observed along with scattered light rain showers lifting northeast across parts of Eastern Oklahoma and Northwest Arkansas. Through the morning hours...light rain showers will remain possible across mainly far Eastern Oklahoma and Northwest Arkansas as the weak front moves eastward through the CWA. Precip should taper off from west to east and is expected to be exiting the CWA by early afternoon as the upper level trof axis shifts off to the east. Also ahead of the front...gusty southerly winds up toward 30 mph will continue to be possible across the CWA early this morning and shift eastward with the movement of the front into Northwest Arkansas by mid/late morning. Behind the front...skies are expected to clear out from west to east with mostly sunny skies forecast this afternoon for the CWA. Also behind the boundary...winds becoming more westerly with a decreasing trend through the afternoon hours are anticipated. Temperatures are not expected to cool with the frontal passage...and with clearing skies and an already warm start to the day...afternoon temperatures well above seasonal average will again be possible. Highs in the mid 60s to lower 70s will be possible. Northerly winds...cooler temperatures and drier air look to begin filtering into the region late tonight into Tuesday as a shortwave drops east southeast through the Plains with an associated frontal boundary moving through the CWA. In the wake of this departing shortwave...a ridge of high pressure is progged move over the Plains Wednesday with more seasonal average temperatures for the second half of the week. Extended model solutions continue to indicate the ridge flatting out Thursday/Friday in response to a shortwave dropping southeast through the Plains...with a second wave within the southern stream pushing across Texas Friday/Saturday. There remains some differences within the details for timing/track/etc. However...rain chances look to become possible Thursday afternoon/night as the northern wave approaches...increase Friday as both waves interact with each other over the Southern Plains...and decrease Saturday as the waves exit the region. Partial thicknesses on the warm side and temperature profiles Friday morning would suggest that precip remains as rain. However...partial thicknesses look to sag southward for Saturday morning which could allow for a light wintry mix within the higher terrain locations of Northwest Arkansas. The GFS kicks out precip before the colder air moves in while the ECMWF holds onto precip a little longer. With the differences between the models this far out have held off on any wintry mention in the grids at this time. Will continue to monitor and update with latest data through the week. && .TSA WATCHES/WARNINGS/ADVISORIES... OK...None. AR...None. && $$ AVIATION.....05