Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Peachtree City Georgia
1247 PM EST sun Feb 7 2016
Previous discussion... /issued 1127 am EST sun Feb 7 2016/
made a few adjustments to temperature/dewpt trends into early afternoon
and slightly higher cloud coverage with some cirrus flirting in
the north. Otherwise forecast on track and previous discussion
Previous discussion... /issued 620 am EST sun Feb 7 2016/
Short term /today through Monday/...
some light precipitation lingering along the far southeastern
reaches of the forecast area early this morning. Temperatures
continue to hold in the lower 40s in that area...but could see some
upper 30s around daybreak before the precipitation pulls completely
out of the area. Left an hours Worth of mixed precipitation in the
grids right at 12z for that possibility...but probability of precipitation are slight chance
at best by then anyway.
Otherwise...no significant departure from previous forecast trends
through the short term forecast period. Dry and seasonal weather
today with precipitation chances returning to the far north after
midnight tonight/Monday morning. Still looking at a rain/snow mix
possible in the mountains early Monday with mainly rain elsewhere
before late in the day when cold air spills south into the area. Wpc
quantitative precipitation forecast a bit higher with this cycle across the mountains Monday
afternoon which bumps up snow accumulation Monday afternoon a small
amount...but mainly at the highest elevations. I do not have a high
enough level of confidence that we will see widespread advisory
level snowfall accumulations in the mountains by the end of the day
Monday to issue a wwa at this time. Will continue to highlight the
potential impacts in the hazardous weather outlook.
Long term /Monday night through Saturday/...
the middle levels will remain very active early next week...while
temperatures remain below normal for this time of year. A warm up to
near normal values is expected by the latter half of the week...with
At the beginning of the period...a strong upper level
disturbance/trough associated with a coastal low will begin to push
up the eastern Seaboard. A secondary longwave trough will dig
southward through Sunday...and remain over the Gulf states through
the middle to late part of the week. A temporary decrease in middle
level forcing will allow for a transition to more orographically
induced precipitation across the mountains overnight Sunday with northwest surface
However...with the strong trough and shortwave energy digging south
on Monday...the orographically produced precipitation will be enhanced by
some middle level forcing later Monday into Tuesday. The trough will
begin to shift offshore on Wednesday.
Atmospheric profiles will be cold enough aloft for snow...and icing
or widespread sleet is not expected. Rain may mix with snow outside
the higher elevations that have probability of precipitation early Monday evening...but
should transition to all snow before 10pm. Precipitation chances continue
into Tuesday...with all snow continuing across northern Georgia...with a
rain snow mix possible outside the higher elevations during the
The latest quantitative precipitation forecast forecasts have no measurable precipitation across the atl metropolitan
for Monday night through Wednesday. This is not unreasonable since
the atmos will be pretty dry. The best accumulation values will
remain across the higher elevations...but even then...values are an
inch or less through 36 hours. Total accumulations through late
Tuesday/early Wednesday across the western facing slopes of the
highest elevations are averaging one to two inches.
Even though snow and or a snow/rain mix is in the forecast for
Monday night through early Wednesday.... snowfall accumulations will
remain on the low side. Precipitable waters will decrease to around a quarter of
an inch (or less) through Wednesday. So...even though we have the
forcing...there won't be much moisture in the atmospheric column.
The best chances for accumulating snow will remain across northern
Georgia...with the greatest potential across the northeast mountains
The potential for black ice will be high...especially from the metropolitan
Atlanta area northward through Wednesday. Any lingering moisture on
the roads is expected to re-freeze overnight and possibly cause
slick spots on roadways...especially bridges and overpasses.
The remainder of the extended forecast remains fairly quiet. There
is some potential for light precipitation on Friday. However...chances
remain too small to mention at this time. However...the system will
need to be watched.
initial VFR conditions with northwest winds 10-12 kts gusting 14-18 kts
this afternoon. Winds decreasing 5-7 kts overnight with some MVFR
ceilings building in after 12z for the northern sites. Ceilings should
hold in 2500-3500 feet range through Monday afternoon with some
possible scattering. Winds also on increase after about 15z to be
more west at 11-14 kts gusting 18-20 kts. Main precipitation chance
should be just north of katl and nearby taf sites near end of
period with a possible -shra to -sn transition though confidence
lacking too much on timing to go other than prob30 -shra at the
//Atl confidence...18z update...
medium on Monday afternoon ceiling scattering.
Low on precipitation chance/type late in period.
High on all else.
Preliminary point temps/pops...
Athens 55 35 47 29 / 0 10 40 30
Atlanta 54 37 46 29 / 0 10 30 30
Blairsville 50 31 41 23 / 0 20 60 60
Cartersville 54 35 46 27 / 0 20 40 30
Columbus 56 36 53 31 / 0 5 20 10
Gainesville 53 36 44 28 / 0 10 50 40
Macon 56 34 55 31 / 0 5 20 20
Rome 55 34 46 27 / 0 30 50 40
Peachtree City 55 35 47 29 / 0 10 30 20
Vidalia 55 37 58 34 / 20 0 20 20