Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Peachtree City Georgia
838 PM EDT Sat Jul 30 2016




Previous discussion... /issued 317 PM EDT Sat Jul 30 2016/

Short term /tonight through Sunday night/...

Short term /tonight through Sunday night...

Little change in the overall pattern this forecast period. The
forecast area remains under the influence of an upper level trough
and weak surface trough through the weekend. Short term models are
in good agreement showing ripples in the upper level flow, however
they are having difficulty handling disturbance moving through north
Alabama and the associated showers/thunderstorms which will move into
north Georgia by 5 PM. Have raised pops, although they remain in the
chance category through this evening as deep moisture and upper
level disturbances will provide a focus for convective development.
Pwats in the 1.5-2.0 inch range support locally heavy rainfall and
ample cape available expect isolated thunderstorms will be possible.
With upper level ripples continuing into the overnight hours have
held slight chance pops overnight with chance pops again tomorrow
afternoon. Guidance temperatures in line and stayed close.

Atwell

Long term /Sunday night through Friday/...
mid to long-range models show good agreement with a weak long
wave trough drifting along the Appalachians and dragging a weak
frontal boundary into the Tennessee Valley region by late Monday. This
coupled with subtle disturbances traversing through the upper
trough should enhance our chances for at least mainly diurnal
driven convection on Monday and Monday night. The upper trough
pushes off the Atlantic coast on Tuesday while high pressure
builds east from Texas. This results in a weak frontal boundary
possibly sagging into central Georgia by late Tuesday while a weak
northwest flow becomes established aloft. This will likely result
in less rain chances across north Georgia and maybe low scattered
coverage across central Georgia for at least Tuesday and Wednesday next
week. Weak disturbances in the northwest flow aloft and increasing
low level moisture may help increase rain chances by Thursday and
Friday just a bit... but still much uncertainty on just how much
influence the ridge pushing in from the west will have on things.

Otherwise... weak shear and only moderate instability continues
to support mainly afternoon and evening general thunderstorms...
with nothing widespread or organized severe expected through the
long term.

The expected increase in clouds and rain chances should help hold
temps closer to seasonal normals on Monday... then this trend may
continue into mid week as a slightly cooler northwest flow becomes
established.

39

&&

Aviation...
00z update...
light rain continues to diminish across the area. Scattered-broken MVFR
possible 10-15z, with some patchy MVFR visibilities. Have included
prob30 thunderstorms and rain for generally 18-00z Sunday. Expect scattered-broken cumulus through
the afternoon. Winds will be SW-west-southwest at 5kt or less overnight, then
increase to 6-9kt by the afternoon. Higher gusts associated with
convective activity.

//Atl confidence...00z update...
medium on ceilings 10-18z.
High on all other elements.

31

&&

Preliminary point temps/pops...
Athens 73 95 73 92 / 30 40 30 40
Atlanta 75 92 74 91 / 30 40 30 40
Blairsville 67 87 67 87 / 30 40 30 50
Cartersville 72 92 72 91 / 30 40 30 40
Columbus 76 94 75 92 / 60 40 40 40
Gainesville 73 91 73 91 / 30 30 30 40
Macon 75 96 75 93 / 60 40 40 40
Rome 72 92 72 92 / 30 30 30 40
Peachtree City 72 92 72 90 / 40 40 30 40
Vidalia 76 96 75 94 / 40 40 40 40

&&

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

$$

Short term...31
long term....djn.83
aviation...31

National Weather Service Glossary of Abbreviations