Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Tallahassee Florida
935 am EDT Fri Mar 14 2014
Near term [through today]...
The 12 UTC regional surface analysis showed a high pressure ridge
along the Piedmont, which will provide our forecast area with east,
and eventually southeast winds today. The previous forecast is on
track, and we expect highs to reach the 70 deg mark in most areas
(but a little cooler at the beaches).
[through 12z saturday]...unrestricted vis and cigs will continue
through this afternoon. East winds 5 to 10 knots will veer to
southeast then south later this afternoon. VFR cigs (10k ft) will
develop late tonight or early Saturday.
Prev discussion [251 am edt]...
Short term [tonight through sunday]...
low temps should begin to moderate tonight as the ridge of high
pressure (responsible for the light freeze over parts of the
interior overnight and the mostly sunny and pleasant day today)
begins to slide eastward off of the NC coast. These lows will still
be a bit on the cool side for this time of year (generally in the
lower to middle 40s away from the coast), but will represent a
moderating trend nonetheless. Still expect Saturday to remain
generally fair and seasonable, although clouds (and slight rain
chances) will gradually be on the increase from the west as the next
low pressure system slated to impact our County Warning Area begins to develop over
Texas with moisture extending well off to its north and east from the Gulf of
Mexico. That said, the heavier rainfall and increasing chances for
some thunderstorms to become mixed in the fold will hold off until
Saturday night and Sunday, with the distinct possibility for some
areas of locally heavy rainfall on Sunday. There are also some
indications that this could be a fairly slow moving and prolonged
event, with both the GFS and European model (ecmwf) indicating rain chances which may
linger well into Tuesday morning. If this becomes the case, the
potential for a locally heavy rainfall event will need to be closely
monitored, especially with some of our area rivers and streams still
with slightly elevated stages and flows. There may also be a smaller
window for a low end severe weather threat near the onset of this
system, but for now, this solution appears confined to the more
bullish NAM members.
Long term [sunday night through thursday]...
the next system still looks on track for Sunday and Sunday night
with rain looking more likely across the area. Thunderstorms remain
possible as well depending on the low track and how much instability
returns northward. Deep layer shear looks fairly impressive with
this system with the 13/06z GFS and 13/00z European model (ecmwf) showing at least 50
knots crossing the area, so we'll need to keep a close eye on the
potential for a few stronger storms, depending on how the details
work out with the surface low track and instability.
Some differences arise in the forecast for Monday as the 13/12z
GFS is much slower than its previous run and the previous European model (ecmwf)
run, resulting in another rainy day. For now, we followed the
13/00z European model (ecmwf) more closely by showing a gradual decrease in pops
from west to east on Monday. The 13/00z European model (ecmwf) is showing another
front approaching by next Thursday while the GFS runs do not have
much with this second system, and the official forecast went with
low pops for now. Temperatures are expected to be fairly seasonal
as it does not look like there will be any big cold blasts
reaching the area through the period.
winds and seas have dropped off significantly overnight as expected
with the ridge of high pressure building in to the north of the
marine area. Generally light to moderate winds and seas will
continue for today through Saturday, before the next low pressure
system begins to ramp up conditions once again by Saturday night and
Sunday. It still appears to be a close call between cautionary and
advisory level conditions as this system develops and heads
eastward, and may not be able to make a definitive call until a
better consensus is reached with the global models. In any event,
the increasing onshore flow on Sunday will result in more dangerous
surf conditions and a likely high risk for rip currents for at least
the second half of the weekend at our area beaches.
low level moisture will be on the increase later today as winds
swing around to become onshore. Minimum relative humidity values are
forecast to be at or just under 25% over most of our Georgia zones
and inland portions of the Florida Big Bend. However, other factors
will not meet local red flag criteria. There are no fire weather
concerns at least through early next week.
area rivers remain below flood stage. Several locations along the
Ochlockonee are in action stage, but are trending downward. However,
as mentioned above, this downward trend is likely to be temporary,
as the potential for at least a moderate to potentially heavy
rainfall event moves into the hsa for the second half of the weekend
into early next week.
Preliminary point temps/pops...
Tallahassee 70 42 75 54 73 / 0 0 10 30 60
Panama City 68 51 70 60 71 / 0 10 20 50 70
Dothan 70 45 72 57 72 / 0 10 20 60 70
Albany 70 43 73 55 72 / 0 0 10 50 70
Valdosta 71 41 77 51 76 / 0 0 10 30 60
Cross City 73 42 76 53 75 / 0 0 10 20 60
Apalachicola 66 49 69 59 70 / 0 0 10 30 60