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fxus62 kffc 130918 

Area forecast discussion
National Weather Service Peachtree City Georgia
418 am EST Wed Nov 13 2019

Short term /today through Thursday/...

With the passage of the Arctic cold front, temperatures have fallen
below freezing everywhere outside the extremely far southeastern
forecast area...however, there's time for them to get there as well.
The freeze warning will continue through 10 am this morning.

On the backside of the upper-level trough axis, differential Ava
will continue to fuel a strong surface high pressure system that
resides over the central Appalachians, and will move off the New
England coast by Thursday morning. This high pressure will dominate
the local weather pattern today with extremely dry air...precipitable waters in
last nights sounding was a whooping 0.08 inches...clear skies and
winds between 5-10 mph out of the east-northeast. Temperatures will remain
unseasonably cold, about 15-20 degrees below normal with high
temperatures topping out in the mid- to upper-40s, and lows in the
upper-20s to lower-30s.

Thursday, another upper-level shortwave trough will be digging down
into the Ozarks plateau, and merge with a cutoff low-pressure system
coming across northern Mexico and far southern Texas. Ahead of this
system, a fetch of Gulf moisture from southwesterly flow will bring
back dense low-level cloud cover, with light rain showers forecast
in the afternoon. At this point, high res models are split on the
coverage and intensity of the forecasted rains, but overall little
impacts are expected.


Long term /Thursday night through Tuesday/...

As the extended period begins, the forecast area will be in
continued southwesterly flow and increasing deep moisture ahead of
an upper-level trough approaching from the west. Scattered to
numerous showers will also be ongoing ahead of the trough. By
Friday, this trough is expected to deepen into a cutoff low as it
moves into southern Alabama, and will continue to move eastward
towards southern Georgia and the Florida Panhandle by Saturday. Some
discrepancies remain in the model guidance with respect to timing
and the track of the cutoff low, with the latest GFS solution moving
the cutoff low northeastward towards the Carolina coast by Saturday
afternoon and the latest European model (ecmwf) solution moving the system more
slowly towards the east Florida coast by Saturday night. As a
result, GFS moves precipitation out of north and central Georgia by
Saturday morning while European model (ecmwf) indicates precipitation will linger
until Saturday evening. Model guidance is trending towards a wetter
solution with greater precipitation coverage. As a result, rain
chances Thursday night into Friday have been increased to high-end
likely pops across much of the forecast area with diminishing pops
across the far northern tier. Pops will then diminish later Friday
into Saturday, given the remaining uncertainty with the timing of
the system. Rainfall amounts associated with this system currently
look to be highest across east-central Georgia, where amounts of 1-2
inches are possible.

On Sunday, an upper level ridge and surface high pressure build in
over the southeastern conus, promoting dry conditions throughout the
day. Another trough then quickly approaches the forecast area in the
early parts of next week, moving over north and central Georgia on
Monday and Tuesday. Moisture associated with this system is
currently expected to be fairly limited, and no more than slight
chance pops are anticipated on Monday and Monday night as a result.
Rainfall totals are furthermore looking negligible, with little to
no measurable precipitation expected at this time. Temperatures will
gradually warm through the extended period. High temperatures of 10-
15 degrees below climatological averages (in the low to mid 50s
across the area) on Friday will steadily increasing each day to 0-5
degrees below average (in the low to mid 60s across the area) by
Tuesday. Lows will similarly run just below average, with
temperatures each morning in the 30s and 40s across the forecast




Records for 11-13

Max temperature min temperature
station high low high low
------- ---------- ---------- ---------- ----------
kahn 83 1931 43 1904 61 1985 23 2013
katl 79 1938 40 1906 66 1879 21 1911
kcsg 84 1915 47 1907 66 1929 28 1968
kmcn 82 1938 47 1911 64 1916 27 2013

Records for 11-14

Max temperature min temperature
station high low high low
------- ---------- ---------- ---------- ----------
kahn 84 1931 38 1976 62 1961 23 2013
katl 80 1955 35 1906 65 1879 22 1969
kcsg 84 1924 46 1976 65 1961 20 1907
1969 1929
kmcn 83 1955 44 1911 65 1929 21 2013

06z update...
VFR conditions expected through the taf period. Gusty north-northwest winds
will be diminishing during the overnight tonight and becoming east-northeast
for Wednesday 10 kts or less. Expecting winds to go from north-northwest to
north-northeast around 08-09z at atl tonight.

//Atl confidence...06z update...
medium to high on overnight wind speeds and gusts.
High confidence on all elements.



Preliminary point temps/pops...
Athens 46 28 45 37 / 0 0 30 70
Atlanta 46 31 45 38 / 0 0 30 60
Blairsville 43 24 46 33 / 0 0 20 40
Cartersville 47 29 48 35 / 0 0 20 50
Columbus 51 34 50 41 / 0 5 40 70
Gainesville 44 29 45 37 / 0 0 30 60
Macon 49 30 48 40 / 0 10 40 70
Rome 48 28 48 35 / 0 0 20 30
Peachtree City 47 30 46 38 / 0 0 30 70
Vidalia 51 35 54 45 / 0 10 30 80


Ffc watches/warnings/advisories...
freeze warning until 10 am EST this morning for the following
zones: Baldwin...banks...Barrow...Bartow...Bibb...Bleckley...
Muscogee...Newton...north Fulton...Oconee...Oglethorpe...
Schley...South Fulton...Spalding...Stewart...Sumter...Talbot...



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