Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Peachtree City Georgia
823 PM EDT sun Apr 26 2015
Previous discussion... /issued 344 PM EDT sun Apr 26 2015/
Short term /tonight through Monday night/...
more stable air working its way into Georgia this afternoon and into
the evening as a as a surface boundary drifts southward. Have
removed all probability of precipitation starting at 00z and have kept the short term dry
with west to northwest flow aloft dominating. Expect a gradual
lowering of dew points through the period. Winds becoming easterly
by Monday night and have lowered the overnight temperatures a bit
along the eastern counties. The only exception to the dry forecast
is a return flow of moisture into the extreme west Central Area
late Monday night as a short wave tracks along the Gulf Coast.
Have introduced slight chance probability of precipitation for that area after 06z
Long term /Tuesday through Sunday/...
no large wholesale changes made to forecast but did refresh based
on latest overall blend. Mainly upped to likely probability of precipitation area- wide
for late Tuesday night and Wednesday with low pushing
northeastward across area. Models still limiting instability with
this system so have kept any chance of thunder to parts of central
Georgia. Quantitative precipitation forecast looks to be around 0.75 to 1 inch. Previous discussion
Previous discussion... /issued 322 am EDT sun Apr 26 2015/
Long term /Monday night through Saturday/...
only one weather system to focus on in the extended. A shortwave
slides across the Tennessee Valley middle week while the surface low tracks along
the Gulf states and across southern Georgia. Although this will
bring bring showers and thunderstorms back to the County Warning Area Tuesday
through Thursday...instability with the system is limited /generally
less than 500 j/kg of MUCAPE/ which will result in mostly showers
for north Georgia and isolated thunderstorms with the showers across
central Georgia where this higher instability is located. Still some
minor differences between the GFS and European model (ecmwf) in terms of features and
timing...but both are in agreement that the best chances for
precipitation will be in the Tuesday night to Wednesday time frame.
After this system moves through...high pressure dominates at the surface
and keeps the County Warning Area dry through the weekend.
IFR that was noted over far north Georgia has lifted to an MVFR
deck but not much progress thus far southward. Do expect some low
clouds to approach later tonight as front moves through but much
uncertainty if this will be a broken or scattered deck. At this time will
just go with a scattered MVFR deck for atl and broken in better moisture
for ahn and mcn. VFR after 15z Monday with lower wind speeds
//Atl confidence...00z update...
medium on MVFR development.
High on remaining elements.
Preliminary point temps/pops...
Athens 54 73 47 67 / 5 5 5 20
Atlanta 54 72 52 66 / 5 0 5 30
Blairsville 44 66 43 64 / 5 0 0 20
Cartersville 49 70 48 67 / 5 0 5 30
Columbus 58 77 57 69 / 0 0 20 40
Gainesville 52 71 47 65 / 5 0 5 20
Macon 56 75 55 68 / 5 0 10 30
Rome 49 70 48 68 / 5 0 5 30
Peachtree City 52 74 51 67 / 5 0 5 30
Vidalia 61 76 58 70 / 5 5 10 30