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Office: FFC

FXUS62 KFFC 170543

Area Forecast Discussion
National Weather Service Peachtree City GA
143 AM EDT Wed Aug 17 2022

.PREV DISCUSSION... /Issued 741 PM EDT Tue Aug 16 2022/

..Updated for 00Z Aviation Discussion...

PREV DISCUSSION... /Issued 255 PM EDT Tue Aug 16 2022/

.Afternoon Area Forecast Discussion...

SHORT TERM /Tonight through Wednesday Night/...

Today is a marked departure from the soupy sensible weather that has
characterized the past several weeks. Thanks to a partial cold
frontal passage, a majority of the residual Gulf moisture in the
column has been effaced (PWAT of 1.09" on the 16/12Z sounding ranks
close to the 10% moving average for this date). A sneaky wedge front
made its way southwestward into and east of the ATL Metro, leaving
much of the aforementioned area under a thick deck of low clouds...
which is still only partially eroded across portions of east central
GA. Any clearing is likely to be short-lived, as a broad shield of
clouds and precipitation associated with a surface shortwave is
currently making its was across the TN River Valley and into north
GA. As a result, highs today are only likely to break 90 across the
far southern portion of the CWA, where conditions have remained
mostly clear to allow for uninterrupted heating. Lows are expected
to drop into the seasonable mid-60s to low-70s.

A deep 500mb trough continues to rotate its way into the southeast,
broadening in size through the end of the short term until its
wavelength encompasses roughly 2/3 of CONUS. As the trough axis
drops southward across the ArkLaMiss overnight tonight, a plume of
moisture coincident with the now-stalled cold frontal boundary sets
up across and just north of the Gulf Coast. These features, along
with any passing shortwave disturbances rounding the base of the
trough, set the stage for what will be a very moist next several
days and ends our *very* transient dry spell. As such, a Day 2
Marginal ERO is in effect for nearly all of north and central GA for
Wednesday to highlight chances for periods of heavy rainfall and
efficient rainmakers (PWATs progged to surge back into the
seasonable 2-2.15" range). Owing to increased cloud cover and PoPs,
highs tomorrow will struggle to get out of the mid-80s, as much as 6-
8 degrees below climo for mid-August.


LONG TERM /Thursday through Tuesday/...

Beginning the long term period, troughing will be over the eastern
US, continuing the NW flow pattern Thursday. The front will continue
to be draped across central and southern Georgia and with this comes
moisture funneling into north Georgia which will increase our PoPs
and start to lower our temps into the 80s across north and central

Starting Friday a low sets up over the northern MS valley, which
will keep troughing over the eastern US, but funnel moisture in from
the gulf from the SW.  The front at this point in the long term
period will still be draped across our area which along with the
upper level moisture will increase our PoPs through the rest of the
period. With this moisture, temps look to stay in the low to mid 80s
across north and central Georgia making for a pleasant week
temperature wise.

With this moisture, comes PWATs in the 2" range through the long
term period which will mean that any showers and thunderstorms that
form will be efficient rainfall producers. Flooding may become a
concern, should heavy amounts of precip occur especially over the
weekend. The severe threat remains to be seen at this time but as
always thunderstorms with gusty winds, frequent lightning, and
heavy rainfall are possible each afternoon.

Temps throughout the period look to remain below climatology norms
throughout the period with the trough setup and abundance of


06Z Update...

Low VFR and high MVFR clouds will gradually fill in over ATL this
morning. Winds will remain light and VRB, but as they pick up they
will become NE where they'll stay for the rest of the day. Light
VCSH is possible this afternoon aft 15Z out ahead of a larger system
that will bring widespread rain and TSRA to the area after 18Z.

//ATL Confidence...06Z Update...

Medium on all elements.



Athens          81  66  79  66 /  60  50  50  40
Atlanta         84  68  80  67 /  60  60  60  50
Blairsville     77  62  77  61 /  60  60  50  30
Cartersville    83  67  81  66 /  60  50  50  40
Columbus        89  70  84  70 /  50  60  70  50
Gainesville     80  66  79  66 /  60  60  50  40
Macon           87  70  84  69 /  50  60  70  50
Rome            85  68  85  69 /  60  50  40  30
Peachtree City  85  67  81  66 /  60  60  60  50
Vidalia         87  71  84  71 /  50  50  80  50




LONG TERM....Hernandez