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fxus64 klzk 212333 
afdlzk 


Area forecast discussion 
National Weather Service Little Rock Arkansas 
533 PM CST Sat Nov 21 2009 


Aviation... 
middle and high level clouds will prevail over much of the area into sun... 
with primarily VFR conds expected. Low pressure along the Gulf Coast 
will continue lifting northeastward tonight and sun. Low level moisture will rotate nwwd 
into parts of central and southeastern Arkansas later tonight and sun...with most 
ceilings around 4-5kt feet. Patchy light rain will effect southeastern Arkansas /mainly kllq/ 
with occasional MVFR ceilings expected. /44/ 
&& 


Previous discussion... /issued 134 PM CST Sat Nov 21 2009/ 


Short term...tonight through Tuesday night 
surface low along the Gulf Coast slowly moving east...with upper 
low/shortwave still in eastern Oklahoma. Rainfall has been spotty 
and light across the state today...and with lack of moisture...not 
expecting much in the way of shower activity tonight. Have left 
slight chances in the south and east...as the low moves 
east/northeast. 


Mostly cloudy skies will remain across the state Sunday 
morning...but will begin to break up during the afternoon hours. Dry 
conditions will continue into Monday...before the next system moves 
in Monday night. 


A cold front will move into the state after midnight Monday 
night...and through the state during the day Tuesday. Have left 
thunder out of the forecast...and think that moisture return will be 
reduced. Have increased probability of precipitation to chance category...but will wait for 
model consistency before increasing any more. 


Long term...Wednesday through Saturday 
models in decent enough agreement initially before diverging 
significantly as the period progresses. GFS pattern is much more 
amplified versus the European model (ecmwf) and drops a significantly stronger upper 
low into the Great Lakes/New England Thursday and Friday versus the 
European model (ecmwf). 


Models continue to show discrepancies late in the period as 
well with GFS advertising a nearly dry zonal flow with European model (ecmwf) showing 
a highly amplified pattern and a very good chance of rain next 
weekend. Needless to say confidence is quite low this period with 
the model differences being what they are. For now will split the 
differences but lean more towards the drier GFS. 


Period initiates with one upper low pulling out and upper ridge over 
the west with a general northwest flow in place. As upper ridge 
builds...another cold front moves through Thursday night but no 
precipitation expected and it will only bring a reinforcing shot of 
cold air. 


As upper flow continues to amplify...north to northwest flow will 
deepen providing the area with a cool but dry Turkey day. As upper 
low pulls out...flow deamplifies and becomes zonal to end the period. 
Will keep the extended dry at this point but probability of precipitation will have to be 
added if European model (ecmwf) is indeed the better choice. Temperatures will average near 
normal Wednesday and below normal beyond. 
&& 


Lzk watches/warnings/advisories...none. 
&& 


$$