Area Forecast Discussion
Issued by NWS Atlanta, GA
FXUS62 KFFC 280150
Area Forecast Discussion
National Weather Service Peachtree City GA
950 PM EDT WED JUL 27 2016
Forecast updated to reflect radar trends and obs. Continuing to
see a decrease in shower activity and cloud cover. Temps look good
with lows in the 70s. Tranquil night expected.
Evening WV loop showing two mid/upper level
highs centered across Great Basin and just offshore coast of
Carolinas (respectively) with a weak vort max sandwiched between
them across AR/MS/LA. A stronger belt of cyclonic flow exists
north of these features with numerous embedded impulses. As these
impulses push east...cyclonic flow will strengthen across the
OH/TN Valleys...ingest the the AR/MS/LA low...and push the
Carolina high east. This will be the beginning of a pattern shift.
In the lower levels...winds will take on a marked increase
overnight between H85 and H7...while a weak lee trough persists
east of the mtns thru Thursday.
For Thursday...aforementioned AR/MS/LA low will shear as it
becomes absorbed in the cyclonic flow. However...its DCVA coupled
with SW upslope flow across higher terrain will support a storm
threat across far north Ga during the afternoon/evening. Mid
level flow approaching 30kts/0-6km shear near 20kts could yield a
few storm clusters...but thinking highest coverage will be across
TN/NC (consistent with current SPC marginal risk depiction). High
PW air and large T and Td spread indicate downburst winds and
heavy rain the main threat with any storm across N Ga.
Otherwise...breezy conditions seem likely by mid morning as low
level flow increases and BL mixes. Temps should be a few degrees
cooler (upper 80s low 90s) N Ga with more cloud cover/shifting of
ridge. Central Ga will top off in upper 90s and stay below heat
.PREV DISCUSSION... /Issued 755 PM EDT WED JUL 27 2016/
PREV DISCUSSION... /Issued 344 PM EDT WED JUL 27 2016/
SHORT TERM /Tonight through Thursday Night/...
No major changes in the short term with the over all atmospheric
pattern. The main east- west oriented upper ridge continues to
control the weather pattern across the southeastern states. the
wave that was over the northern gulf yesterday is now a weak low
center rotating near the LA/AR/MS border. Showers and
Thunderstorms are rotating northward across MS and AL and into
West Central GA this afternoon. Right now we are only seeing
showers as the best instability continues to stay west of our
area. With the increased gulf moisture moving into the region
coverage may be a bit more Thursday than today. Temps should
continue slightly above normal with Heat Index values remaining
below 105 so no advisory expected.
LONG TERM /Friday through Wednesday/...
No major changes needed to the long term portion of the forecast.
Ridging aloft begins to break down by Friday into early Saturday as
a weak trough/shear axis develops across AL. This shear axis/trough
will settle across northern GA for much of the weekend into early
next week. At the surface...weak lee trough may try to set up across
north eastern GA as high pressure remains situated across the
southern CWFA. The ridging aloft should begin to build back over the
area by the middle of next week.
Scattered showers and thunderstorms are expected each day and should
be diurnal in nature. Highest pop values should be in the vicinity
of the shear axis/trough or the surface trough through early next
week. The current grids reflect this...so didn`t make any changes.
No strong indicators for widespread severe weather are noted at this
One thing to watch...the 00Z run of the ECMWF and the new GFS bring
a low pressure system into the Caribbean by the early/middle part
of next week.
FAIRLY QUIET PERIOD ON TAP FOR ALL TAF SITES. TRANQUIL NIGHT
EXPECTED...WITH THREAT OF LOWER CLOUD BLANKET EXPECTED TO STAY
NORTHWEST OF METRO SITES. BY MID-MORNING THURSDAY...WINDS WILL
BEGIN TO PICK UP ALONG WITH DEVELOPMENT OF DIURNAL CU DECK. KEPT
PROB30S OUT OF ALL TAFS FOR NOW...AS LATEST GUIDANCE SUGGESTS
GREATEST PRECIP THREAT WILL STAY TO THE NORTHWEST. WINDS CONTINUE
FROM THE SW THRU THE PERIOD...GENERALLY 5-15KT WITH GUSTS UP
TOWARDS 20KT THURS AFTERNOON. NO RESTRICTIONS TO VSBYS.
//ATL Confidence...00Z Update...
HIGH ON ALL ELEMENTS
.PRELIMINARY POINT TEMPS/POPS...
Athens 75 96 73 93 / 10 20 20 30
Atlanta 75 92 72 89 / 20 20 20 30
Blairsville 70 86 69 84 / 20 40 40 50
Cartersville 74 91 72 88 / 20 30 30 40
Columbus 74 95 74 94 / 30 20 20 20
Gainesville 74 91 72 88 / 20 30 30 40
Macon 75 98 74 97 / 10 10 10 20
Rome 73 91 72 89 / 20 50 40 50
Peachtree City 73 93 73 90 / 20 20 20 30
Vidalia 76 99 74 99 / 10 10 10 20