169 
fxus64 ktsa 202115 
afdtsa 


Area forecast discussion 
National Weather Service Tulsa OK 
315 PM CST Friday Nov 20 2009 


Discussion... 
closed upper low over far southern Texas this afternoon will 
continue to move very slowly east over the next 48 hours with an 
inverted surface trough over the forecast area. This will continue to 
influence our weather through Saturday at least...mainly keeping a 
moist airmass in place with considerable cloud cover through at 
least early Sunday. Precipitation chances will be diminishing tonight 
across most of the area but will linger across southern and 
eastern sections to some degree through Saturday to the east of 
surface trough. Expect clouds and lack of meaningful temperature advection to 
keep a limited diurnal temperature range and have mostly sided warmer 
than mav on lows and cooler on highs. Even though widespread low 
clouds tonight...based on forecast soundings the lowest levels will 
continue to moisten enough for areas of fog to form. Do not feel 
that visibilities less than 1/4 mile will be widespread enough though to 
warrant an advisory. 


Attention will turn to next approaching system early next week. 
With exception of GFS...recent model runs keep trending toward a 
slower and deeper solution with this system...UKMET being the 
deepest. With this in mind have sided more closely with the European model (ecmwf) 
for early next week...meaning better opportunity for moisture to 
return ahead of the low with a slower frontal passage. Thus have 
raised precipitation chances for Monday night and Tuesday...and added a 
slim chance of thunder for Monday night. 


Cooler airmass will eventually settle over the region by later 
next week after the system slowly pulls away and surface high builds 
into the region. Possible wrap around low clouds and wind will 
keep nighttime temperatures up until the end of the week...when the first 
opportunity for a widespread freeze occurs. Incidentally this 
would be the second latest occurrence of the first freeze at 
Tulsa international on record. 


&& 


Preliminary point temps/pops... 
tul 49 59 47 62 / 20 10 10 10 
fsm 49 58 43 64 / 50 30 10 0 
mlc 50 60 46 64 / 30 20 10 10 
bvo 46 61 42 62 / 20 10 10 10 
fyv 45 56 40 61 / 40 20 10 0 
byv 44 57 42 59 / 30 20 10 0 
mko 48 58 43 62 / 30 20 10 10 
Mio 47 59 44 63 / 20 10 10 10 
f10 48 58 45 62 / 30 20 10 10 
hhw 49 61 44 63 / 40 20 0 10 


&& 


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


$$ 


Short term...06 
long term....14