727 
fxus64 kmeg 030144 
afdmeg 


Area forecast discussion 
National Weather Service Memphis Tennessee 
744 PM CST Tuesday Dec 2 2008 


Discussion... 


The winds have become light at many locations allowing the 
temperature to drop a little lower than previous thoughts. However 
with the pressure gradient tightening...the winds should pick up 
in the next couple of hours from the southeast and help mix the 
air. When this occurs temperatures will rise a little and/or 
remain steady the rest of the night. The low temperature tonight 
will likely occur before 10 PM. Have made minor adjustments to 
hourly grids to relect this trend. 


Ac 


&& 


Previous discussion... /issued 535 PM CST Tuesday Dec 2 2008/ 


Discussion... 


Progressive upper level pattern will continue over the lower 48 
states through the next seven days. At discussion time... skies were 
clear under northwest flow aloft. GOES water vapor imagery showed 
a rather strong upper level trough diving southeast into the Great 
Basin. This feature will drop into northeast nm / southeast nm by 
sunrise Wednesday...with a surface low developing along a cold 
front in central OK. Low level pressure gradient over the midsouth 
will sharpen considerably by morning...leading to a breezy day 
for the midsouth on Wednesday. 


The upper trough will lift into the upper Midwest in by sunset 
Wednesday evening...pulling the cold front through the midsouth 
during the evening and early overnight period. This front 
represents the leading edge of airmass that was centered over Alaska 
this morning. With moist modified Gulf air lifting over the 
advancing front... rain is a good bet for all the midsouth until 
the front clears early Thursday morning. 


For the Thursday through weekend periods... northwest flow aloft 
will prevail over the midsouth...with a reinforcing push of dry 
Canadian air on Friday. 


GFS puts the midsouth into low level southerly return flow 
Monday...followed by a frontal passage and scattered showers 
Monday night into Tuesday. European model (ecmwf) is also wet during this 
period...but gets there with a slightly different solution. For 
now...it looks like we can maintain forecast continuity through 
next Tuesday...but the middle part of next week is more uncertain 
due to model differences. 


Pwb 


&& 


Aviation... 


00z taf cycle 


VFR conditions will persist through the period for sites east of 
the Mississippi River. Low level clouds will be on the increase on 
Wednesday morning but should remain above 3kft east of the River. 
West of the Mississippi River...some MVFR sky conditions may 
develop by Wednesday afternoon with clouds lowering and thickening 
through the afternoon at all locations. Rain should hold off until 
after 00z Thursday at all locations. Winds should become gusty 
again on Wednesday ahead of an approaching cold front. 


Jlh 


&& 


Preliminary point temps/pops... 
mem 40 60 35 44 / 0 40 90 10 
mkl 33 56 34 42 / 0 30 100 10 
jbr 38 56 33 40 / 0 70 70 10 
tup 36 62 38 48 / 0 10 90 10 


&& 


Meg watches/warnings/advisories... 
Arkansas...none. 
MO...none. 
MS...none. 
Tennessee...none. 
&& 


$$