042 
fxus64 ktsa 231239 
afdtsa 


Area forecast discussion 
National Weather Service Tulsa OK 
639 am CST Monday Nov 23 2009 


Aviation... 
concerning taf sites ktul/krvs/kmlc/kxna/kfyv/kfsm. 
Scattered MVFR ceilings and isolated IFR conditions 
in eastern Oklahoma this morning due to pockets of low 
stratus and fog...otherwise VFR today. VFR at northwest 
Arkansas sites through 00z. Risk of showers / isolated 
thunder all sites could result in MVFR conditions overnight. 




&& 


Previous discussion... /issued 249 am CST Monday Nov 23 2009/ 


Discussion... 
water vapor imagery depicts fast moving shortwave passing through 
the forecast area at this time with negligible impact on the 
sensible weather. Some spotty low clouds are noted across parts of 
eastern OK/western Arkansas...although these should mix out later this morning. 
With southerly flow developing ahead of next upper low and 850 temperatures 
warming to around 8-10c...expect another mild day with temperatures 
bouncing back well into the 60s. 


Aforementioned upper low is currently dropping into the northern 
rockies...and will swing across Kansas overnight. 00z European model (ecmwf)/GFS are very 
similar with the timing of the upper low and associated cold 
front...with the front moving into eastern OK toward midnight and 
exiting the area late Monday night. 00z NAM is about 3-6 hours 
slower. Expect scattered showers and perhaps some thunderstorms to 
eventually develop along the front. While shear is relatively 
impressive...low-level moisture and instability is quite 
meager...so will only include a slight chance of thunder overnight. 
Tricky low temperature forecast given the uncertainty in frontal 
timing...and could see a rather tight thermal gradient across the 
region by Tuesday morning. 


Precipitation should be exiting western Arkansas Tuesday morning...with 
cooler air spreading east. Clouds may hang around for a good part of 
the day in the cyclonic flow aloft...which should hold daytime temperatures 
in the 50s for much of the area. A reinforcing shot of colder air is 
slated for Thanksgiving day...as a deep upper low moves across the 
Ohio Valley. This system exits quickly...with a widespread freeze 
likely by Friday morning as surface ridging builds over the plains. 


Should see a brief warmup by Saturday...with another cold front 
potentially impacting the region Saturday night into Sunday. Have 
introduced low probability of precipitation for this time period. 


&& 


Preliminary point temps/pops... 
tul 66 40 52 36 / 0 30 10 0 
fsm 67 49 59 36 / 0 50 20 0 
mlc 68 45 57 36 / 0 40 0 0 
bvo 64 38 50 33 / 0 30 10 0 
fyv 63 48 52 34 / 0 50 20 0 
byv 59 44 56 35 / 0 50 20 10 
mko 65 47 54 34 / 0 40 10 0 
Mio 64 49 52 36 / 0 40 10 10 
f10 66 41 54 36 / 0 40 10 0 
hhw 69 51 61 39 / 0 40 10 0 


&& 


Tsa watches/warnings/advisories... 
OK...none. 
Arkansas...none. 
&& 


$$ 


Short term...21 
long term....05 
aviation...21