Area Forecast Discussion Issued by NWS Atlanta, GA
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000
FXUS62 KFFC 260743
AFDFFC
Area Forecast Discussion
National Weather Service Peachtree City GA
343 AM EDT Tue Mar 26 2024
...Morning Area Forecast Discussion...
.SHORT TERM...
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(Today through Wednesday)
Issued at 335 AM EDT Tue Mar 26 2024
As the upper trough becomes negatively tilted through the course
of the day, a strong embedded shortwave will quickly eject over
the Mississippi Valley northeastward into southeastern Canada. The
surface low will follow suit and quickly zip off to the northeast
over the Great Lakes Region. A line of showers and embedded
thunderstorms ahead of the attendant cold front will march
eastward and arrive in northwest Georgia this morning as a surface
low tracks along the Gulf Coast. Isolated to scattered showers as
well as a few thunderstorms ahead of the main push are also
possible, as we have already seen this morning. Recent model
trends suggest a further northward push of a plume of instability
into the metro area today coinciding with the organized line of
convection. MUCAPE around 100-250 J/kg and 0-1km bulk shear
~35-50 KT will be sufficient to support updrafts embedded within
the line. Southeast winds will also remain strong through the
early afternoon where sustained winds between 15 and 25 mph could
gust as high as 45 mph. A Wind Advisory remains in effect until
2PM this afternoon for portions of north and western Georgia.
Winds are expected to diminish quickly this afternoon from the
northwest as the pressure gradient slackens with the weakening of
the surface high over the Mid-Atlantic.
Later this afternoon, the line is expected to slow considerably
and will bifurcate the forecast area along a southwest to
northeast axis. At this time, the warm front will be draped over
central Georgia and cyclogenesis in the northern Gulf will produce
a secondary wave of convective activity along the boundary that
is expected to last through the end of the short term period.
Ahead of this next wave, temperatures are expected to be well into
the mid to upper 70s with dewpoints in the low to mid 60s. During
Tuesday`s overnight and Wednesday`s early morning hours, an
additional plume of instability will overspread areas south of
I-20. Within this surge, MUCAPE will range from 500-700 J/kg for
areas east of I-75 and south of I-16 and ~30KT of 0-1km bulk
shear. Scattered to numerous showers and thunderstorms will linger
through Wednesday afternoon across east central Georgia until the
next shortwave embedded within the 500 mb flow helps shift the
system off to the east with the cold front pushing into northwest
Georgia. At this time, the threat for severe weather is low
throughout the short term period, but strong gusty winds, locally
heavy rainfall, and frequent lightning will be the primary
concerns in any thunderstorms that develop. Areas northwest of the
convective activity will experience the gradual scattering of
clouds during the afternoon hours as the cold front marches
southeastward.
KAL-- End Changed Discussion --
&&
.LONG TERM...
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(Wednesday night through Monday)
Issued at 335 AM EDT Tue Mar 26 2024
The long term period picks up on Wednesday night into Thursday
morning as the mid-/upper-level trough that was talked about in
the short term discussion shifts eastward over the Southeast. A
jet streak/vort max passing through the base of the trough over
the Gulf Coast is progged to generate an area of low pressure over
the southern portion of the Eastern Seaboard. The SREF projects a
30% to 50% chance for CAPE > 500 J/kg across our southeastern
counties on Wednesday night through early Thursday morning, and
bulk shear will be strong within the aforementioned jet streak, so
this will translate to a chance (20% to 40%) for thunderstorms
across east-central Georgia. Across the rest of the CWA, isolated
to scattered showers can be expected during this time frame.
Instability is expected to wane by late Thursday morning as a cold
front pushes through the CWA with much drier air in tow. Showers
are expected to taper off across the western half or so of the
CWA, but continue across the eastern half or so through Thursday
afternoon, where moisture is slower to scour out behind the front.
Behind the cold front will be an expansive area of high pressure
across the Southeast while upper-level ridging encompasses much of
the eastern CONUS. Fire weather conditions (relative humidity,
winds/gusts, and finer fuel moistures) will bear watching on
Thursday, Friday, and Saturday as conditions warm up and dry out.
Martin-- End Changed Discussion --
&&
.AVIATION...
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(06Z TAFS)
Issued at 205 AM EDT Tue Mar 26 2024
MVFR cigs at TAF locations this morning. Conditions will
deteriorate through TAF period as a line of SHRA/TSRA moves
through the area today. Line with embedded TSRA will impact the
metro area beginning around 15-17Z but SHRA will be possible
through the morning hours. Strong ESE winds at 10-15 KT will gust
to 25-28 KT through the afternoon Tuesday. Winds will shift to NW
after 04Z Wednesday. Cigs/vsbys will drop to IFR after ~12Z and
approach LIFR after 02-04Z Wednesday as winds slacken to 4KT or
less.
//ATL Confidence...06Z Update...
High confidence on winds. Medium confidence on all other elements.
KAL-- End Changed Discussion --
&&
.PRELIMINARY POINT TEMPS/POPS...
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Athens 66 51 75 50 / 90 60 30 40
Atlanta 66 51 73 49 / 90 30 10 20
Blairsville 57 45 70 43 / 100 40 10 20
Cartersville 65 47 71 45 / 100 20 10 10
Columbus 71 54 77 51 / 90 30 20 30
Gainesville 61 50 74 49 / 100 40 20 30
Macon 75 58 77 51 / 80 70 50 50
Rome 67 46 72 44 / 100 10 0 10
Peachtree City 68 51 74 47 / 90 30 20 20
Vidalia 80 63 73 56 / 30 70 90 80-- End Changed Discussion --
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 2 PM EDT this afternoon for GAZ001>009-
011>016-019>022-030>033-041>044-052-053-066-067-078-079-089>092-
102>104.
&&
$$
SHORT TERM...KAL
LONG TERM....Martin
AVIATION...KAL