Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Peachtree City Georgia
953 PM EST Thursday Nov 27 2014
overall forecast looks to be on track and have made no significant
changes to the forecast at this time. Have made minor adjustments
to hourly temperature and sky grids to account for latest cooling
trends and persistent cloud cover across north Georgia. Still
anticipate this cloud cover to dissipate overnight.
Previous discussion... /issued 652 PM EST Thursday Nov 27 2014/
Previous discussion... /issued 249 PM EST Thursday Nov 27 2014/
Short term /tonight through Friday night/...
Strong shortwave trough continues to move east of the local area
but this has failed to eradicate the to low to middle clouds that
engulf most of north Georgia. This continues to play havoc with
temperatures this afternoon with areas in the mountains struggling
to reach the lower 40s. Have had isolated reports of light flurry
activity through the noon hour...but losing influence of shortwave
should allow for none probability of precipitation the remainder of the short term period.
Looks like we are on tap for a very cold Thanksgiving night with
the potential for a hard freeze across portions of north Georgia.
Low clouds will continue to impede radiational cooling initially
but should only result in temperatures being a degree or two
higher than model consensus.
Remainder of the short term is quite benign with no probability of precipitation in the
forecast and a subtle moderating trend with highs on Friday
approaching the 50 degree mark.
Long term /Saturday through Thursday/...
few changes to the long term. Models agree on draping frontal
boundary across the northwest portions of the state and bringing
chance of showers across this area Monday night into Tuesday
morning. While there is still disagreement for middle-week next week,
the European model (ecmwf) is a little less enthusiastic on precipitation chances for
Wednesday/Thursday than it was in the previous model run. Have
slight chance probability of precipitation across portions of north Georgia on Wednesday
morning but will have to see if trend will be to back down from
rain chances during this time frame.
GFS/European model (ecmwf) in good agreement through the upcoming weekend...then
differences begin. Both models show rising 500 mb heights with high
pressure shifting to our east bringing US a south to southwest low
level flow...ie warming temperatures. By Monday Canadian high
pressure builds into the upper Midwest pushing a cold front into
the Ohio and Mississippi valleys. Both GFS/European model (ecmwf) bring this front
into the Tennessee Valley Monday/Tuesday but they differ on the
amount of moisture with the European model (ecmwf) a little less aggressive. Will
keep probability of precipitation confined to north Georgia as both models also weaken the
front. Then as we push into middle week next week both models are out
of sync with each other with positions of short waves and location
of deepest moisture. Until there is more model consensus will go
with less than slight chance probability of precipitation for Wednesday/Thursday.
VFR through the period. Winds will dissipate overnight from 8-10kt
this evening to 5kt or less by 12z. Northwest winds will slide to the west
and then SW by Friday evening.
//Atl confidence...00z update...
high on all elements.
Preliminary point temps/pops...
Athens 27 47 30 57 / 0 0 0 0
Atlanta 28 48 34 58 / 0 0 0 0
Blairsville 26 47 29 55 / 0 0 0 0
Cartersville 26 48 29 58 / 0 0 0 0
Columbus 29 52 33 61 / 0 0 0 0
Gainesville 29 47 32 56 / 0 0 0 0
Macon 28 52 29 60 / 0 0 0 0
Rome 27 48 28 59 / 0 0 0 0
Peachtree City 25 49 29 59 / 0 0 0 0
Vidalia 33 52 34 61 / 0 0 0 0