Scientific Forecaster Discussion
Area forecast discussion...updated
National Weather Service Peachtree City Georgia
901 PM EDT Sat Aug 29 2015
updated forecast in good shape. Rain showers still active in northwest
corner...middle Georgia east of kcsg and far southeast. Little if any
convection seen this afternoon and none expected overnight.
Another round of rain showers likely early Sun morning based on hrrr and
some hires models. Not a slam dunk but enough to keep probability of precipitation fairly
high for that time of night.
Previous discussion... /issued 333 PM EDT Sat Aug 29 2015/
Short term /tonight through Sunday night/...
the short term models are in good agreement through the period
keeping a moist airmass in place. The upper level low over the
northern Gulf will continue to lift across South Alabama into
northwest Georgia by Sunday evening and north of the forecast area
Sunday night. Weak impulses will continue to lift across the
forecast area ahead of the low. High pressure over the Carolinas
will keep easterly flow at the surface. This will reinforce some
lower clouds by morning across the area with middle level ceilings
expected across the region. Although instability will be
minimal...isolated thunder will be possible as the impulses lift
north through tomorrow. The areas of showers will continue
overnight...with best chances over West Georgia...but do expect some
lulls. Guidance temperatures are in line and have taken a blend of
Long term /Monday through Saturday/...
no major changes to the ongoing long term forecast.
The remnants of Erika still expected to impact the County warning forecast area next week.
For now...the system will remain a low pressure trough as it comes
onshore across the Florida Panhandle early next week.
The persistent southerly flow aloft will bring abundant moisture
northward from the Gulf of Mexico for much of next week...so chance
probability of precipitation still needed every day. In addition...an upper trough across
the eastern half of the country will help keep temperatures mostly
in the 80s through the period.
Wind shear in the Gulf is a little weaker...so some regeneration of
Erika is possible.
primary concern is chance for IFR ceilings Sun morning and chance for thunderstorms and rain
Sun afternoon. Decent chance for another round of morning rain moving
in from the south after 08z at atl metropolitan airports. Could see ceilings
drop to IFR and linger into the late morning...though climatology
does not often support this in late August. Still appears
possible. After rain moves out...should see some clearing and scattered
thunderstorms and rain. Have added prob30 for thunderstorms and rain 19-22z. After 00z should be
clearing quickly. East component winds 5-10kts expected through forecast.
//Atl confidence...00z update...
low confidence on rain showers/IFR ceilings Sun morning.
Medium-high confidence on MVFR ceilings Sun morning and thunderstorms and rain
likelihood Sun afternoon.
High confidence on all other elements.
Preliminary point temps/pops...
Athens 68 81 67 85 / 40 50 20 30
Atlanta 69 82 69 85 / 50 50 20 20
Blairsville 63 76 62 82 / 40 40 20 30
Cartersville 67 81 66 87 / 40 40 20 20
Columbus 70 87 69 89 / 40 50 20 20
Gainesville 67 78 67 83 / 40 50 20 30
Macon 69 84 69 87 / 50 50 30 30
Rome 68 82 66 87 / 40 40 20 20
Peachtree City 67 83 68 86 / 50 50 20 20
Vidalia 71 86 70 85 / 60 50 40 50