Area forecast discussion
National Weather Service Peachtree City Georgia
408 am EDT Friday may 24 2013
Short term /today through Saturday/...
deep upper trough remains in control of the eastern Seaboard...with
exiting front moving into the Atlantic. Flow is transitioning to
northwest aloft as cool Canadian high pressure slides down from the
Great Lakes today. Surface gradient will remain strong today...but
though winds should remain just below advisory criteria it will
likely still be enough to warrant fire danger conditions...see below
for more on that. Strong cold air advection in the wake of the frontal passage and
with the northwest flow aloft will lead to much cooler temperatures
today than yesterday by a good 6-8 degrees all but extreme southern
zones. The cooler temperatures and breezy conditions for today will be the
start to a very pleasant Memorial Day weekend.
As the trough axis shifts east later today and tonight a cutoff low
will form over the New Jersey area. The 00z European model (ecmwf) is a tad faster
and a little stronger than the GFS but they along with the NAM are
in good agreement with their lack of impacts to the southeast. The
big story will be low temperatures tomorrow night...which will flirt
with or possibly drop below record lows. Current record for mcn is
49 and we have 48 forecast. Other sites look to be just above but
this will be reevaluated later today. Winds will be significantly
decreased on Saturday as the ridge axis settles over the area.
Amplitude of the longwave pattern will decrease some on Saturday
leading to slightly warmer conditions all except extreme southern
zones /which should be a little cooler on Saturday compared to today
as the cold air advection finally gets down there/...but still several degrees
below seasonal normals and overall a great day to be outside.
Tdp
Long term /Saturday night through Thursday/...
mostly a dry forecast through the period. Georgia under northwest
flow aloft into the first of the week. GFS/European model (ecmwf) show a series of
weak impulses moving southeast that may affect mainly north Georgia.
However impulses are hard to time and models differ in amount of
moisture with each. For now a slight chance looks reasonable across
the north on Sunday and again Monday. Upper ridge builds over the
state into the remainder of the week. At the surface...high pressure
over the Atlantic will give a moist southeast flow to the area but
this may only mean an increase in cloudiness. Upper ridging should
help to suppress thunderstorm development. Have generally made only
minor tweaks to the temperatures.
41
Fire weather...
fuels dried across the area yesterday with significant portions of
southwest and northwest zones dropping below 8 percent. The rest of
the area hovered generally between 9 and 10 percent. Winds today
should reach the 15 miles per hour fire danger criterion and some areas in
northeast Georgia may drop below 25 percent relative humidity. Rather than getting
fancy with trying to pick and choose counties...feel it is best to
just issue a Fire Danger Statement for the entire area. With breezy
conditions today...fuels should dry further and expect that another
Fire Danger Statement will be needed on Saturday. Duration of relative humidity
values below 25 percent on Saturday will need to be closely
reevaluated in the event a red flag warning is warranted.
Tdp
&&
Climate...
Records for 05-24
Maximum temperature min temperature
station high low high low
------- ---------- ---------- ---------- ----------
kahn 96 1912 65 1966 71 1998 42 1931
katl 95 1996 60 1895 72 2000 45 1892
kcsg 97 1996 73 1977 74 1996 51 1954
kmcn 97 1960 65 1899 73 2000 46 1931
&&
Aviation...
06z update...
VFR through the period. Few middle to high clouds this morning should
give way to sky clear by this afternoon. Northwest winds 5-10kt to start the
period will increase to between 12-15g20-25kt this
afternoon...subsiding again around sunset. Expect a shift to the
NE overnight tonight...current timing at 07z for atl.
//Atl confidence...06z update...
medium on timing of wind shift early Saturday morning.
High on all other elements.
Tdp
&&
Preliminary point temps/pops...
Athens 78 47 78 51 / 0 0 0 0
Atlanta 76 51 77 55 / 0 0 0 0
Blairsville 72 41 74 47 / 10 0 0 5
Cartersville 74 44 78 47 / 5 0 0 0
Columbus 83 52 82 55 / 0 0 0 0
Gainesville 76 49 76 53 / 5 0 0 0
Macon 82 48 80 50 / 0 0 0 0
Rome 75 45 78 46 / 5 0 0 0
Peachtree City 78 44 79 45 / 0 0 0 0
Vidalia 86 53 83 54 / 0 0 0 0
&&
Ffc watches/warnings/advisories...
none.
&&
$$
Short term...tdp
long term....41
aviation...tdp
