Area forecast discussion
National Weather Service Tallahassee Florida
422 am EDT Sat may 18 2013
Near term [through tonight]...
a broad shortwave trough sprawls the eastern part of the country
this morning, with high pressure dominating at the surface. Through
the day, the trough will continue its gradual eastward motion in
response to an amplifying ridge upstream. As it does so, it may send
just enough energy our way to generate a cluster of thunderstorms
around mid to late afternoon across portions of Alabama and Georgia.
Generally, expect the target region for thunderstorms to be between
Dothan and Tifton, moving southeast and mostly diminishing by the
time it reaches Valdosta. Elsewhere across Alabama and Georgia,
scattered light showers and isolated storms may be possible. Little
to no rain is expected across North Florida. Thus, we will see
warmer temperatures in Florida, and slightly cooler temperatures to
the north and northwest. Expect highs around the 90 degree mark for
much of inland Florida, with even some lower 90s possible from
Valdosta, southeast into The Big Bend. Middle to upper 80s will be
more common where thunderstorms are anticipated this afternoon.
Overnight, showers and thunderstorms will retreat back to the north,
closer to the parent synoptic forcing. Temperatures will fall back
into the lower to middle 60s, with fog developing near dawn.
&&
Short term [sunday through monday]...
very summerlike conditions are expected across the region for both
Sunday and Monday, as the shortwave trof axis, which will begin the
weekend to our north, gradually slides eastward to a position off
the eastern Seaboard by Monday afternoon. This will allow for upper
level ridging to build in from the west, with high temps expected to
reach the lower 90s each day over the interior, with lower to
perhaps mid 80s near the coast. This shortwave trof may provide just
enough lift and instability to combine with the daytime heating to
produce isolated to scattered showers and thunderstorms. The best
chances for rain will be across eastern portions of the County Warning Area (nearest
the trof), but even here, 30% should be the greatest value.
&&
Long term [monday night through friday]...
the 500mb ridge over the southeast U.S. Early in the work week will
transition to a weak trough by late week. The height falls over our
forecast area will be modest so only a slight increase in pop is
expected later in the week. Until then, the GFS forecasts more deep
layer moisture (hence qpf) than the European model (ecmwf) for our region.
Climatologically it's still a bit early for widespread mesoscale-
induced convection, so an average of the two solutions will get US
close to our climatological pop (around 20%), with a diurnal
cycle. High temperatures will be at or a few degrees above
average, with lows near average (in the 60s).
&&
Aviation...
IFR restrictions in a mix of low ceilings and fog are anticipated at
all terminals but kaby this morning. Similar to yesterday
restrictions will lift shortly after sunrise. Scattered
thunderstorms are expected to impact primarily kaby, and possibly
kdhn later this afternoon. Fog, possibly more widespread than this
morning, is expected once again tonight.
&&
Marine...
generally light onshore winds and low seas will dominate our coastal
waters for the next several days, with just some minor enhancements
near the coast with the afternoon sea breeze.
&&
Fire weather...
relative humidity values will remain above critical levels for the
next several days, with relatively light transport winds and deep
mixing heights. Thus, red flag conditions are not expected in the
foreseeable future.
&&
Hydrology...
area rivers and streams will remain well below flood stage for the
next several days with very little rain in the forecast.
&&
Preliminary point temps/pops...
Tallahassee 89 62 91 64 91 / 10 10 20 10 20
Panama City 83 67 84 68 85 / 10 10 10 10 10
Dothan 87 65 90 66 92 / 40 20 20 10 10
Albany 85 64 90 66 91 / 50 20 20 30 20
Valdosta 93 63 92 64 92 / 20 20 30 20 30
Cross City 90 63 88 65 89 / 10 10 20 10 30
Apalachicola 83 66 82 66 84 / 10 0 10 10 10
&&
Tae watches/warnings/advisories...
Florida...none.
Georgia...none.
Alabama...none.
GM...none.
&&
$$
Near term...Harrigan
short term...Gould
long term...Fournier
aviation...Harrigan
marine...Gould
fire weather...Harrigan
hydrology...Gould
