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Area forecast discussion 
National Weather Service Peachtree City Georgia
356 PM EDT Wednesday Oct 1 2014

Short term /tonight through Thursday night/...
morning fog deck has lifted with an extensive cumulus deck forming in its
wake. This has not had too much of an effect on temperatures except
to the south where a slower climb has been experienced but still
anticipate those areas to reach forecast highs.
Otherwise...continuing to monitor transition from very light flow to
more of a southerly regime as high pressure slowly drifts to the
east. On a broader scale...all eyes are to the west where strong
shortwave is moving out of The Four Corners and into the Central
Plains and promises to be our main weather maker for Friday into
Friday night.

For the remainder of the short term though...tranquil weather in
store initially as subtle ridge builds in advance of upper level
trough. With southerly flow developing just off the
surface...should see good moisture advection tonight leading to
another round of low clouds and potential fog. Best locations for
this look to be from csg to mcn and points south but low clouds
look to impact as far north as the atl metropolitan by Thursday morning. Have
patchy fog in the grids primarily as flow should remain just
strong enough but will need to monitor closely for possible
adjustments upward on dense fog potential.

By Thursday night...northwest zones get into more of a diffluent
pattern aloft as ridge slides east allowing for disturbances to
race across the area overnight. Models in agreement on one such
disturbance pushing across and enhancing precipitation potential from 06z
to 12z. Still enough residual surface cape and MUCAPE to warrant
thunderstorm formation with this activity. Shear will also be
supportive a few strong to possibly severe storms in this initial
portion but the majority should hold off until Friday.

As far as Friday...continued categorical probability of precipitation through the period
and main focus was on severe potential. Although parameters look
like they are having a hard time lining up and much will depend on
timing...there remains a decent chance of strong to severe storms
with potential cape values of 1500 to 2000 and a quick shot of
strong low level shear. At this time...have beefed up wording in
severe weather potential statement to include possible isolated tornadoes for northwest as both stp
plots and local sherb index indicate potential.

Deese



Long term /Friday through Wednesday/...
upper ridge moving off the Atlantic coast Thursday night as a cold
front enters the MS valley. Front approaching northwest Georgia around
18z Friday and moving through the forecast area Friday afternoon and
into Friday night. Instability sufficient for thunderstorms during
that time with best convective available potential energy around 1500 and lifted index values of
minus 3 to minus 5. Could also see some isolated severe storms
especially across northwest Georgia where the best instability and moisture
line up Friday morning/afternoon. The biggest threat from any
thunderstorms that develop Friday will be strong gusty
winds...periods of heavy rain...frequent cloud to ground lightning
strikes...and the possibility of isolated tornadoes. Sharp trough
crossing the southeast Saturday and Sunday with dry and colder
air. Some modification for the first of the week. Looks like a
short wave moves across the Ohio/Tennessee valleys on Tuesday and have
included low probability of precipitation across the far north. Temperatures should be
warm for Friday ahead of the front...but clouds and rain will
modify those values. Temperatures cooling down for the weekend.

01



&&



Climate...



Records for 10-02

Maximum temperature min temperature
station high low high low
------- ---------- ---------- ---------- ----------
kahn 94 1911 53 1958 70 1926 38 1924
katl 89 1986 59 1958 72 1910 42 1895
1910
kcsg 93 1986 62 1958 72 2005 42 1984
1986
kmcn 94 1971 65 1958 72 2005 39 1984
1926

Records for 10-03

Maximum temperature min temperature
station high low high low
------- ---------- ---------- ---------- ----------
kahn 91 1986 56 1958 71 2007 38 1974
katl 94 1911 57 1958 70 2007 40 1981
1986
1884
kcsg 93 1954 62 1958 71 2007 43 1974
1995
1985
kmcn 95 1911 60 1958 71 1937 39 2011
1927

Records for 10-04

Maximum temperature min temperature
station high low high low
------- ---------- ---------- ---------- ----------
kahn 96 1954 59 1957 71 1941 36 1987
katl 91 1954 61 1957 71 1941 39 1987
1941 1899 1884 1974
kcsg 94 1954 65 1975 73 2007 40 1974
1957
kmcn 95 1954 61 1899 73 1911 36 1987
1974

Aviation...
18z update...
morning fog over the south has lifted into a dense cumulus deck from
csg to mcn with slightly less cloud coverage as you progress north
toward atl. Expect VFR cumulus for the remainder of this afternoon and
then clearing skies. Increasing moisture from the south overnight
however will lead to a return of low clouds and potential fog for
mcn and csg. Expect this to reach atl around daybreak in the form
of a scattered to broken deck around 3k feet which will lift quickly to 5k
for the remainder of the day.

//Atl confidence...18z update...
high on all elements.

Deese

&&

Preliminary point temps/pops...
Athens 58 85 65 78 / 0 5 20 80
Atlanta 65 85 68 78 / 0 5 40 80
Blairsville 53 81 60 74 / 0 5 60 90
Cartersville 56 86 66 78 / 0 0 50 90
Columbus 64 86 69 80 / 0 5 20 80
Gainesville 62 84 66 76 / 0 5 40 80
Macon 59 86 67 82 / 0 5 10 70
Rome 54 87 65 77 / 0 0 70 90
Peachtree City 57 85 66 77 / 0 5 30 80
Vidalia 65 85 65 83 / 5 5 5 60

&&

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

$$

Short term...deese
long term....01
aviation...deese

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