Weather

894 
fxus62 kcae 060908 
afdcae 


Area forecast discussion 
National Weather Service Columbia SC 
408 am EST Tuesday Jan 6 2009 


Synopsis... 
a stationary front will remain north of the area today. A cold 
front will cross the region Wednesday. Cool and dry weather will 
follow for the end of the week as high pressure returns. 


&& 


Near term /until 6 PM this evening/... 
a stationary front was north of the SC border early this morning. 
Warm air advection/isentropic lift was producing showers over the 
northern and central midlands. The area of showers is expected to 
lift northward this morning as the upper ridge strengthens over the 
southeast. Showers may linger over the extreme north midlands into 
this afternoon. Models indicating much lower probability of precipitation over the 
southern midlands and csra. Temperatures in the lower 60s this morning 
..so we're expecting another mild day with highs in the middle/upper 
60s north with low/middle 70s across southern half of the area. 


Tightening pressure gradient and strong h850 jet will bring 
increasing winds to the region today. Have issued a lake Wind 
Advisory for late this afternoon through Thursday afternoon. 




&& 


Short term /6 PM this evening through Thursday/... 
upper ridge over the southeastern states will keep unseasonably 
warm air over the region through tonight. Heights falling 
Wednesday when a deep trough approaches and a cold front moves 
through. Probability of precipitation increasing to the categorical range tonight into 
Wednesday morning as the upper short wave and surface cold front 
moves through the area. Front and precipitation should move east of the 
area by Wednesday afternoon when high pressure and colder air move 
in. Models still indicating weak instability ahead of front so 
expect mainly showers instead of thunderstorms. Shear will be 
strong so if thunderstorms can develop then damaging wind would be 
possible. Also expect breezy winds Wednesday behind the front 
with tight pressure gradient and and subsidence. 


&& 


Long term /Thursday night through Monday/... 
very few changes were made for the extended forecast. 
Previous discussion: high pressure and dry air mass behind the 
front should dominate through Friday. The GFS has been consistent 
showing the next cold front and shower chance Saturday. Moisture 
is low with this system so will keep probability of precipitation in the slight chance to 
low chance range. Temperatures should be near seasonal normals 
through the extended range. 


&& 


Aviation /06z Tuesday through Saturday/... 
frontal boundary to our north...with an upper impulse tracking 
across the region overnight. Models indicate best precipitation threat 
mainly to our northwest and north tonight. Radar loop indicates precipitation area 
to affect cae/cub in the short term and will handle that with a 
tempo group...otherwise vcsh should handle it. Mostly cloudy skies 
and an increase in boundary layer wind overnight will reduce fog 
threat...but stratus formation is possible...and lamp guidance 
generally indicates MVFR conditions tonight for most of our taf 
sites. Our forecast area to remain in the warm sector Tuesday as warm front 
lifts NE across NC...and cold front remains to our west. Area of low 
pressure to ride NE along the front allowing for a tighter pressure 
gradient. This along with enhanced mixing due to warm temperatures could 
lead to breezy conditions Tuesday. 


Extended outlook...cold front will come through Wednesday bringing 
the best chance of precipitation and associated restrictions to cigs/vsbys. 
No significant impacts expected Thursday through Sat. 


&& 


Cae watches/warnings/advisories... 
SC...lake Wind Advisory from 5 PM this afternoon to 5 PM EST 
Thursday for scz015-016-018-020>022-025>031-035>038-041. 
Georgia...Lake Wind Advisory from 5 PM this afternoon to 5 PM EST 
Thursday for gaz040-063>065-077. 


&& 


$$ 
Synopsis...10 
near term...10 
short term...10 
long term...10 
aviation...22