Scientific Forecaster Discussion
fxus62 kffc 281203 aaa
Area forecast discussion...updated
National Weather Service Peachtree City Georgia
803 am EDT sun may 28 2017
near term forecast appears in good shape with main line of
convection completely dissipated. Line of convection over eastern
Alabama has strengthened a little, but very little lightning observed
and not expected to intensify this morning.
Previous discussion... /issued 428 am EDT sun may 28 2017/
Short term /today through Monday/...
main focus on chance for severe convection. Near term, final round
of storms entering northeast Alabama at this writing, and showing signs
of weakening. Expect weakening to continue but with ample MLCAPE
and decent deep layer shear, could see a few severe storms thru
the rest of the night and into Sunday morning. After this final
round dissipates, should be fair with little precip. New convection
expected to develop in the afternoon well west of the area over
the lower MS valley into northern MS and develop into northern Alabama
tonight. Could see a few isolated storms develop late this
afternoon and perhaps some storms moving in from Alabama later tonight,
but no widespread strong or severe storms expected.
On Monday, 00z model guidance shows broad troughing over the
Midwest with trough axis developing back in the Southern Plains
and lower MS valley, which brings flow aloft to more swly
direction. Deep layer shear improves again with 0-6km bulk shear
around 30-35kts and MLCAPE values progged back up to 2500-3500
j/kg with most favorable values over middle Georgia 18z Mon-06z Tue.
As it was current system, low level shear will be very weak and
any storms will likely be outflow dominant with little risk of
Long term /Monday night through Saturday/...
as broad upper trough slides east over the northern states, weak
westerlies still in place over southern states Wed-Fri. Hard to
rule out isolated convection even after front pushes south of the
area tues. Deep moisture finally spreads back in starting thurs
night and thunderstorms and rain chances go up slowly accordingly. More coverage
likely in afternoon/evening. Deep shear quite a bit weaker in this
pattern so severe storms not as likely as they are in current
pattern. Will still need to watch.
line of rain showers west of atl in eastern Alabama should weaken this morning
but will continue to monitor. Rest of day should be fine with MVFR
cigs due to cumulus 18-22z. Any rain showers/thunderstorms and rain this afternoon and
evening will be isolated, not enough confidence or expected
coverage to mention in forecast. Sfc winds will come back to SW
with a few gusts to 15-20kts likely this afternoon.
//Atl confidence...12z update...
high on all elements.
Preliminary point temps/pops...
Athens 87 70 87 67 / 70 20 20 30
Atlanta 86 71 84 68 / 20 30 30 30
Blairsville 80 63 79 61 / 70 40 40 40
Cartersville 85 68 83 66 / 30 30 30 30
Columbus 89 73 87 70 / 20 20 30 30
Gainesville 84 69 83 66 / 60 30 30 30
Macon 90 72 89 69 / 30 20 30 30
Rome 85 68 83 66 / 30 30 30 40
Peachtree City 86 70 85 67 / 20 30 30 30
Vidalia 92 74 92 72 / 10 10 20 20