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fxus62 kffc 190838 aaa 
afdffc 


Area forecast discussion 
National Weather Service Peachtree City Georgia 
440 am EDT Friday Mar 19 2010 


Short term /today through Sunday/... 
rather zonal southern stream jet extending roughly between 25 and 
30 degree latitude from northern Mexico across the Gulf and through 
Florida. A shortwave middle/upper tropospheric ridge was to our west 
this morning and will build across Georgia today as a surface high 
also slides crosses the southeastern states. The subsidence from 
this deep layer ridge will keep skies clear and temperatures mild 
and slightly above climatological averages today and Saturday. A 
northern stream trough digging into the intermountain west today 
will buckle the longwave pattern generating a deepening upper low 
and associated surface low over the Southern Plains on Saturday 
which moves into the middle Mississippi Valley by Sunday. 
Several lobes of vorticity rotate around the upper low into Georgia 
underneath considerable diffluence ahead of approaching h2 jet 
streak. Instability minimal (capes generally less than 200 j/kg) 
but with fairly strong dynamics expect some thunder on Sunday in 
fairly widespread rain ahead of a cold front nearing from the 
west. Precipitation amounts typically around a half inch and 
possibly up to an inch expected with this fairly fast moving 
system. 


Long term /Sunday night through Thursday/... 
frontal passage expected from west to east across Georgia Sunday evening with 
precipitation winding down by midnight Monday over the local area. The low 
level cold pool accompanying the upper low as it moves into the 
Tennessee Valley and southern Appalachians is quite impressive 
with a blob of 800 mb temperatures in the -1 to -7 degree c range crossing the 
area Tennessee and northern Alabama/Georgia Monday morning. Instability strato 
cumulus/showers/drizzle likely on Monday. Surface temperatures/wet 
bulbs probably just a tad too high for anything but cold 
rain at the surface in most areas...but GFS thermal profiles at 
the highest elevations of the north Georgia mountains look supportive 
of a a rain/snow mix...generally above 3000-3500 feet. Plan to 
keep all rain for now...but will monitor model trends as the 
NAM/sref should come into focus on this better than the global 
models. Lingering influence of the upper low sliding to our east 
remains through Monday night...before high pressure and a warmer 
airmass builds in from the west Tuesday through Thursday. That 
will lead to a middle-week return of above normal temperatures and 
dry conditions. 


Rrh 
&& 


Aviation... 
no significant weather concerns and VFR conditions expected through 12z 
Saturday. Upper ridge axis to slide across the state today. After 
after ridge axis passes...high level clouds associated with system 
approaching the plains will remain well west of the area. Could see 
few middle clouds near top of mixed layer this afternoon...but not 
likely. Surface winds will remain west 4-8kts through the period. 


Snelson 


&& 


Preliminary point temps/pops... 
Athens 75 43 76 51 64 / 0 0 5 10 80 
Atlanta 70 47 73 51 63 / 0 0 5 20 80 
Blairsville 68 39 67 47 59 / 0 0 5 20 80 
Cartersville 71 39 73 49 62 / 0 0 5 30 80 
Columbus 73 44 74 52 65 / 0 0 5 30 80 
Gainesville 72 46 72 52 61 / 0 0 5 20 80 
Macon 75 42 74 50 67 / 0 0 5 10 80 
Rome 72 40 72 49 62 / 0 0 5 30 80 
Peachtree City 71 39 73 48 64 / 0 0 5 20 80 
Vidalia 75 48 77 54 71 / 0 0 5 10 70 


&& 


Ffc watches/warnings/advisories... 
none. 
&& 


$$