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Area forecast discussion...updated for aviation 
National Weather Service Peachtree City Georgia
140 PM EDT Monday Jul 28 2014

Update...

Surface front just south of Atlanta to Athens. Have tweaked the probability of precipitation
only slight. Still have best chances mainly across central zones
this afternoon.

41



Previous...
short term /today through Tuesday/...
/issued at 411 am EDT Monday Jul 28 2014/
regional radars show a line of showers and thunderstorms moving
across north Georgia this morning. This convection is developing just
ahead of a cold front that is prognosticated by models to push across the
forecast area today. Hi-res models show the current convection
moving across north Georgia weakening early this morning to mainly just
scattered showers as the convection moves into the Atlanta metropolitan
area by 6 am to 8 am this morning. Although a weakening trend is
noted and expected... MUCAPE values of 2000-2500 j/kg and 20-30kt
wind shear values are noted across north Georgia this morning just ahead
of the convection. This suggest the potential for at least a few
embedded thunderstorms could persist as the convection pushes
southward through the morning. Will continue to mention chance for
thunderstorms for areas southward. However... severe storms are not
expected with this initial line of convection through the morning.

The greatest strong to severe storm concern continues to be across
central Georgia later this afternoon as the front pushes into a much more
moist and unstable environment during maximum daytime heating. As the
front pushes toward a Columbus to Macon line between 4-6 PM this
afternoon... models continue to show stronger storms firing along
and ahead of the front. MLCAPE cape values of 3000-4000 j/kg...
coupled with 40-50 knots middle level shear suggest the potential for
isolated strong to severe storms across parts of central Georgia this
afternoon and evening. Storm Prediction Center continues to show a slight risk area
generally along and south of a Columbus to Macon line for this
afternoon and evening. The main threats are expected to be large
hail and damaging winds. This isolated severe potential should push
south of the forecast area by 8-10 PM this evening... with clearing
conditions behind the front.

A much cooler/drier air mass will spread over the forecast area
tonight... bringing unseasonably cool temperatures the area through middle
week...with near record lows expected tonight as temperatures drop into the
lower to middle 60s for most areas... and highs on Tuesday struggle to
get into the middle 80s for north Georgia... upper 80s to lower 90s look
reasonable for parts of central Georgia on Tuesday.

39



Long term /Tuesday night through Sunday/...
/issued at 411 am EDT Monday Jul 28 2014/
weak surface high pressure over the area to start the extended
forecast. An upper level deep long wave trough also moves in over
the region and settles in through the end of the week. This trough
pulls in some drier air and lower dew points and cooler
temperatures Tue/Wed. By Thursday moisture begins to increase again across
western and southern portion of our County Warning Area with diurnally driven
slight to low chance probability of precipitation in across the area through days 6 and 7.

01



&&



Climate...

Records for 07-29

Maximum temperature min temperature
station high low high low
------- ---------- ---------- ---------- ----------
kahn 103 1952 69 1984 76 1993 60 1911
1981
katl 103 1952 73 1984 77 1993 63 1977
1926 1986
1896
kcsg 101 1952 74 1984 78 2010 65 1994
kmcn 104 1986 74 1984 78 1986 63 1897
1952

Records for 07-30

Maximum temperature min temperature
station high low high low
------- ---------- ---------- ---------- ----------
kahn 102 1999 69 1984 76 2010 60 1925
1915
katl 98 1986 68 1984 78 1896 61 1936
1980
kcsg 102 2010 76 1984 79 2010 65 1957
1986
kmcn 103 1986 74 1984 76 2010 62 1920
2008
1958

Records for 07-31

Maximum temperature min temperature
station high low high low
------- ---------- ---------- ---------- ----------
kahn 103 1999 71 1916 76 1931 59 1936
katl 99 1999 62 1936 78 1915 59 1936
1986 1896
1980
kcsg 104 1986 74 1997 78 2011 66 1997
1981 2010
kmcn 105 1986 68 1936 77 1931 61 1936

&&

Aviation...
18z update...
surface front just south of atl to ahn. Across central Georgia scattered
thunderstorms possible this afternoon with a few becoming strong.
Convection ending early evening. North Georgia taf sites VFR through the
period with sctattered cumulus this afternoon. Winds west to
northwest 10 to 12kt with higher gusts diminishing after 00z. VFR on
Tuesday with northwest winds 10kt occasionally gusty.



//Atl confidence...18z update...
medium concerning convection... high for all other elements.



41



&&

Preliminary point temps/pops...
Athens 93 64 87 64 / 50 10 5 5
Atlanta 89 66 85 65 / 50 10 5 5
Blairsville 82 60 79 55 / 30 10 10 5
Cartersville 88 62 84 61 / 50 5 5 5
Columbus 95 67 89 66 / 50 20 5 5
Gainesville 89 65 84 64 / 50 10 5 5
Macon 97 65 90 63 / 60 20 5 5
Rome 88 62 85 61 / 40 5 5 5
Peachtree City 90 63 85 60 / 50 10 5 5
Vidalia 98 71 91 67 / 70 60 5 5

&&

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

$$

Short term...41
long term....01
aviation...41

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