Area Forecast Discussion
Issued by NWS Atlanta, GA
FXUS62 KFFC 241430
Area Forecast Discussion
National Weather Service Peachtree City GA
930 AM EST Fri Feb 24 2017
Fog has rapidly dissipated across most of the area and will be gone
completely within the next hour. Updated the short-term forecast
grids, mainly for skycover, to reflect current trends. Still looking
for record or near record temperatures this afternoon with ample
sunshine ahead of the approaching cold front that will bring the
region back to nearer-to-normal temperatures for the weekend.
.PREV DISCUSSION... /Issued 646 AM EST Fri Feb 24 2017/
PREV DISCUSSION... /Issued 337 AM EST Fri Feb 24 2017/
SHORT TERM /Today through Saturday/...
Near term starts with challenge of fog development and what coverage
will come to fruition in the early morning hours and near sunrise.
Dewpt depressions in the valleys of the far north and some
scattered other locations have been supportive of patchy fog
formation soon but mainly due to the radiational component.
Support for thicker/more widespread development would need to come
from the additional aid of low level Atlantic moisture advection
from the east and so far the fetch hasn`t seemed to be oriented
favorably enough for this to occur. Not ruling dense fog out
completely but thinking just isolated for now and will monitor if
any Special Weather Statement or advisory will be warranted later
Otherwise today should be partly cloudy with increased warm
advection ahead of a cold front passage overnight tonight.
Afternoon max temps should flirt with records for many areas as we
are looking to have upper 70s to low 80s for the majority of the
CWA. The cold front and associated increase in precip chances
should push across the NW majority of the area between midnight
and sunrise Saturday morning. The upper level dynamics around the
associated trough will provide rather strong deep layer shear and
while low level bulk shear is marginal (near 30 kts) the
environment will be supportive of damaging wind potential with any
stronger storms. Overall progged instability ahead of this system
looks to be better than some of the past few fropa`s...though
thermal soundings are indicating a possible 700mb warm nose that
could inhibit what`s attainable in the full column aloft. SPC has
expanded the Day 1 Marginal Risk a bit farther south to include
portions of north GA (mainly north of Atlanta). Thinking chance of
thunderstorms overall is a bit higher after midnight now too but
intensity should be mainly kept to some strong and isolated severe
cannot be ruled out. Otherwise overall precip coverage not
impressive and becomes mainly isolated along leading edge of front
after about 6 AM. Resultant storm total rainfall only about a
tenth to quarter inch.
Daytime Saturday should have rapid clearing behind the
aforementioned front with enhanced gradient NW sfc winds of 15-20
mph as a much drier airmass is ushered in with a 1025 sfc ridge
settling in quickly for the region. Look for resultant temps to
become below normal...yes below...to kick off the start of the long
term Saturday night.
LONG TERM /Saturday Night through Thursday/...
The long term starts will dry weather as surface high pressure
moves to the southern Appalachians and TN valley Sunday morning
and to the east coast by days end Sunday. This will provide
clear or nearly clear skies. Saturday daytime winds will diminish
Saturday night as the surface high moves to the region.
Forecast low temperatures will run about 6-7 degrees below normal
Sunday morning and near normal Sunday afternoon.
Starting Monday the weather becomes rather wet and unsettled as a
moist southerly overrunning flow develops along with the passing
of an upper level short wave with deep moisture associated. GFS
and European seem to be in good agreement with this. Highest pops
will be over n GA will little or no instability expected.
Instability increases Monday night and Tuesday with the highest pops
continuing over n GA as a moist s-sw flow continues with a chance of
thunderstorms. GFS and European then differ with the timing of the next
cold front on Wednesday/Wednesday night with the GFS much faster.
Leaned closer to the European on timing based on previous timing and
collaboration with BMX. Even with the slower Euro...all precip
looks to be over for Thursday.
Temperatures are expected to be above normal for much of the long term
after Sunday...then close to normal Thursday with the frontal passage.
Records for 02-24
Max Temperature Min Temperature
Station High Low High Low
------- ---------- ---------- ---------- ----------
KAHN 81 1930 37 1947 58 1944 19 1989
KATL 77 1982 35 1907 64 1890 17 1989
KCSG 81 1930 38 1901 61 1979 21 1989
KMCN 79 1985 36 1901 62 1961 18 1901
Initial VFR conditions with potential for MVFR or lower Cigs
coming in from the southeast from possible fog/low level moisture
for the first few hours this morning - mainly concern for KMCN and
KAHN. Otherwise today should have SCT cu field in 4-6 kft and
possible clearing late before cigs lowering again tonight ahead
of front and increased shower/isolated tstorm chances. Winds
mainly SE today 6-9 kts getting close to due south late afternoon
but mainly staying just east of south for KATL until 05z Saturday
when swings to the SW. Expect quick clearing and increase in NW
winds/gusts for Saturday behind front around 13-15z.
//ATL Confidence...12Z Update...
Medium on initial VSBYs and late period cigs.
High on all else.
.PRELIMINARY POINT TEMPS/POPS...
Athens 78 56 67 32 / 5 30 30 0
Atlanta 78 56 63 34 / 10 40 30 0
Blairsville 71 50 58 26 / 10 60 30 0
Cartersville 78 53 60 28 / 10 50 30 0
Columbus 80 58 66 36 / 5 20 20 0
Gainesville 75 54 62 33 / 10 50 30 0
Macon 81 57 70 33 / 5 20 20 0
Rome 78 52 59 29 / 10 60 20 0
Peachtree City 79 54 63 30 / 10 40 30 0
Vidalia 81 58 75 40 / 0 10 20 0