Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Peachtree City Georgia
1036 PM EDT Sat Jul 23 2016



Update...
showers and thunderstorms have diminish this evening. Have
tweaked pops and hourly temps/dews. No other changes needed.

&&

Previous discussion... /issued 746 PM EDT Sat Jul 23 2016/

Previous discussion... /issued 145 PM EDT Sat Jul 23 2016/

Short term /tonight through Sunday night/...
the morning sounding showed ample deep layer moisture and moderate
instability... with 1.7 pws and around 2500-3000 j/kg of afternoon
cape. This coupled with a weak upper disturbance settling over
north Georgia has resulted in scattered to numerous showers and
thunderstorms already developing across most of north Georgia. Although
this convection will be strong at times... no expecting much
severe storm threat as some warm air in the upper mid levels
should help hold most convection down just below severe limits
this afternoon and evening... with the main threats being wind
gusts in the 35-45 mph range... very heavy rain due to slow moving
storms and cloud to ground lightning. These storms should
gradually dissipate through mid to late evening with loss of
daytime heating... and although cannot rule out an isolated
shower or storm overnight... will likely show none pops after
midnight. Models show the upper disturbance currently over MS-al-
Georgia drifting further west on Sunday while another disturbance
southeast of the Georgia coast drifts west across south Georgia on Sunday.
This suggest the greater convective threat on Sunday will be west
and south of the forecast area. However... with ample moisture and
moderate instabilities still in place... will continue to show at
least a 30 percent chance of afternoon and evening storms on
Sunday...but severe storms are not expected at this time.

Otherwise... see no major changes in temperatures with lows mainly
in the 70s and highs in the 90s. Heat index values of 99 to 103
degrees are expected on Sunday... so no heat advisory is
anticipated at this time.

39

Long term /Monday through Saturday/...
no major changes were made to the extended periods. The previous
discussion follows. 20

Previous long term.../issued at 315 am EDT Sat Jul 23 2016/

Long term /Sunday night through Friday/...
the long term starts off with an upper level ridge across the
southern Appalachians and an easterly wave moving across Florida. The
GFS has this wave affecting central Georgia more than the NAM or
European models. At this time think convection will be highly
diurnal Sunday evening.

The upper level ridge pattern continues for Monday with mainly
afternoon showers and storms. Most high temperatures will again
be in the 90s except upper 80s for portions of the mountains.

The upper ridge moves over the area for Tuesday and Wednesday but
slightly weaker and continues to slightly drift S Thursday into
Friday. This should continue the pattern of mainly diurnal showers
and storms across the area...favoring the mountains and portions of
West Georgia. Highs in the 90s will continue for most areas and slightly
cooler in the mountains.

Bdl

Aviation...
00z update...
showers/thunderstorms have diminished over the last hour or so
with loss of heating. Expect some residual convective debris for
the next several hours. Winds will be light out of the SW
overnight. Although there was some precipitation this afternoon,
still feel any sub-VFR cigs/vsbys early am will be limited due to
sufficient dew point depressions. Showers/thunderstorms should
initiate around 18z tomorrow, possibly along any outflows south of
atl. South-southwest/SW winds through tomorrow afternoon/evening.

//Atl confidence...00z update...

Medium on convection timing and coverage on Sunday.
High on remaining elements.

&&



Preliminary point temps/pops...
Athens 74 97 74 95 / 40 30 20 40
Atlanta 75 94 75 93 / 40 30 20 40
Blairsville 68 90 68 89 / 40 50 20 50
Cartersville 73 95 73 93 / 40 40 20 50
Columbus 75 96 75 95 / 30 30 20 40
Gainesville 74 94 74 93 / 40 40 20 50
Macon 74 97 74 95 / 30 30 20 40
Rome 73 96 73 94 / 40 40 20 50
Peachtree City 73 95 72 93 / 40 30 20 40
Vidalia 75 97 74 95 / 30 30 20 30

&&

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

$$

Short term...39
long term....20
aviation...26

National Weather Service Glossary of Abbreviations