Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Peachtree City Georgia
414 am EDT Sat Jul 4 2015
Flash Flood Watch for north Georgia through Sunday evening...
Short term /today through Sunday/...
current radar loop shows showers and isolated thunderstorm across
most of north and central Georgia with more precipitation moving
in from Alabama. All in all we are in a very moist near zonal flow
pattern which continues to send one wave after another across the
southeast. This will continue to support multiple rounds of
showers/thunderstorms that should persist through at least Sunday
night. Have broad brushed occasional to chance probability of precipitation across the
entire area through the weekend as timing and intensity of each
wave will be difficult to get a handle on. This is a very rapidly
changing environment with the only constant being north and
central Georgia getting more and more precipitation every hour. The
forecast models are in good over all agreement but they are also
showing some differences in timing and intensity. One good thing
is the models are showing a bit less instability developing this
afternoon so should mainly see just general thunderstorms across
the area today. Given moist environment and limited heating due to
clouds and rain...severe potential will generally be low.
However...we can not rule out a severe storm or two moving in out
of Alabama later this afternoon. If we see any they should be
isolated and short lived. The same should be the case for Sunday
as well. Have also extended the Flash Flood Watch until Sunday
evening for continued precipitation through the weekend. Looking
for 1 to 3 inch totals across north Georgia through Sunday.
Long term /Sunday night through Friday/...
by Monday...upper level trough axis is over the eastern two thirds
of the area with some middle level drier air noted for the northern
County Warning Area with precipitable water dropping to 1.4 inches. Overall would
expect this to result in a reduction in coverage of storms over
previous days and plan to continue lowering probability of precipitation through the end
of the forecast. Drier air continues for Tuesday before eroding
away and giving way to a bit of increased moisture for the
remainder of the long term. With middle and upper level ridge
building in however...upper level energy is much reduced through
the period and diurnally favored chance probability of precipitation look suffice for the
grids. Remainder of the forecast is on track and no major changes
showers and thunderstorms continuing across the area this morning
as another line moves in from Alabama. This second line is staying
south of the atl area taf sites but it will affect csg and mcn.
Seeing a lot of lightning and very gusty winds with this system.
The atl area taf sites will see some precipitation over the next few
hours but looks like it should be mainly showers. The forecast
models are showing the main axis of moisture staying mainly of Georgia
today and Sunday so will see rain showers/thunderstorms and rain through out the taf period.
Winds expected to stay mainly out of the west in the 6-16kt range.
Will see higher gut with convective activity. Ceilings will be up
and down through the taf period ranging from VFR to MVFR.
//Atl confidence...06z update...
confidence medium on all elements
Preliminary point temps/pops...
Athens 84 70 85 69 / 60 60 60 40
Atlanta 83 71 84 70 / 60 70 70 40
Blairsville 75 64 78 63 / 90 70 70 50
Cartersville 81 68 83 67 / 80 70 70 40
Columbus 87 72 87 71 / 60 60 70 40
Gainesville 79 69 82 68 / 70 70 70 50
Macon 90 71 89 70 / 50 60 70 40
Rome 82 69 83 68 / 90 70 70 40
Peachtree City 84 70 84 69 / 60 70 70 40
Vidalia 93 71 91 72 / 40 40 70 40
Flash Flood Watch through Sunday evening for the following