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Area forecast discussion...updated aviation 
National Weather Service Peachtree City Georgia
639 PM EST Friday Feb 27 2015

Short term /tonight through Saturday night/...
/issued at 244 PM EST Friday Feb 27 201/
still a lingering black ice concern for parts of the far north. Have
decided to extend Special Weather Statement to cover area that still shows snow cover on
latest visible Sat...into Saturday morning. This will be mainly north of
a Rome to Canton to Cleveland line.

Otherwise...main forecast concern is with overrunning Gulf moisture
against a developing classical cad wedge late in the period...mainly
Saturday night into Sunday morning. Strong 1040+mb surface high will
slide into the northeast for Saturday and the low level wedge
temperature/dewpoints into the overnight combined with timing of upglide waves
will be critical as to any freezing rain potential in the northeast
portion of the County Warning Area for early Sunday. Thermal profiles greatly differ
at this time as the GFS is decently cooler than the NAM...though both models
indicate good upglide along the 295 Theta surface for eastern portions
of the area...starting as early as Saturday afternoon. For now have
trended slight to chance probability of precipitation earlier...based on the aforementioned
isentropic analyses and support from consensus of hi-res model
reflectivity...beginning light rain in the far southeast for
Saturday afternoon and becoming more widespread to the north for the
overnight. Surface temperatures and prognosticated wetbulbs look to be supportive of
light freezing rain mainly north and east of a Ellijay to
Gainesville to Athens line in the 08-14z period. Thankfully...quantitative precipitation forecast
does look to be pretty light and any ice accumulations should range
from a glaze to just under a tenth of an inch. For now do not have
much confidence in the extent and amount for any particular wwa
products...though would not be out of the question for future Special Weather Statement or
advisory potential if more consensus can be reached. Wpc did include
freezing rain to our northeast again...with extent and amounts similar to
mentioned above. Will keep a close eye on this and make adjustments
as necessary.

Baker



Long term /Sunday through Friday/...
/issued at 244 PM EST Friday Feb 27 201/
put most of our focus on the short term portion of the forecast
so did not make any major changes to the extended. Progressive
nature of the upper flow moves the surface ridge off the east by
later in the day Sunday through Sunday night so the threat for
icing appears to be limited to early Sunday morning. Confidence is
low to medium at best right now. Upper- level flow is beginning to
amplify by early next week and this trend continues through the
remainder of the extended forecast period. Fortunately Georgia
remains on the warmer...southwest flow...side of the amplifying
pattern. Weak front drops into the vicinity Monday/Tuesday but
washes out with little to no upper support. Instability looks
marginal at best for thunder. Much better chances for thunder
Wednesday and Wednesday night associated with an approaching cold
front and strong short wave. Cooler and drier airmass builds in
for the end of the week in the wake of this system.

20/01



&&

Aviation...
00z update...
VFR conditions will persist through early Sat morning. Then around
09-11z Sat... guidance is suggesting a transition to MVFR ceilings for
the Atlanta taf sites as a deep easterly flow sets up. Still expect
morning MVFR ceilings to scatter by 16-18z with some middle level clouds
around 8-10kft lingering Sat afternoon. Model guidance is mixed on
timing of MVFR ceilings returning Sat night-Sun morning. Have leaned
toward holding off until after 03z Sat for now. Current northwest winds
will swing over NE around 05-07z tonight... then remain east the
rest of the taf period. Expect winds speeds to increase by 15z Sat
with gusts around 16-18kts during the day. Precipitation chances begin to
increase from the southeast beyond the forecast period into early Sunday.

//Atl confidence...00z update...
medium on ceiling timing.
High all else.

39

&&

Preliminary point temps/pops...
Athens 31 44 32 45 / 5 10 40 40
Atlanta 32 48 35 49 / 5 10 30 40
Blairsville 24 42 30 44 / 5 10 40 40
Cartersville 24 46 34 48 / 5 10 30 40
Columbus 36 53 40 55 / 5 20 30 30
Gainesville 29 42 32 46 / 5 10 30 50
Macon 33 49 38 53 / 5 20 30 30
Rome 24 50 34 48 / 5 10 30 40
Peachtree City 30 50 35 50 / 5 10 30 30
Vidalia 38 49 39 57 / 10 30 30 30

&&

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

$$

Short term...Baker/39
long term....01
aviation...39

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