Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Tallahassee Florida
748 PM EDT Tuesday Jul 28 2015
Near term [through tonight]...
The 7 PM EDT regional surface analysis showed an east-west
oriented trough across north FL, and a weak, broad low pressure
system across central Georgia. Vapor imagery and upper air data showed
a high pressure system centered over AR, and lower heights across
much of the eastern Continental U.S.. there remained a region of considerably
drier air above 500 mb, as well as a relatively dry, but narrow zone
between 850 mb and just above the surface. These dry slots
appeared to be limiting the amount (and intensity) of updrafts,
and only isolated thunderstorms were occurring across our region
early this evening. Storms were more numerous to our north, and
they were generally drifting southward, but we think most of them
will dissipate before reaching our region.
[through 00z wednesday] outside of a few isolated thunderstorms and rain this
evening, we expect generally VFR conditions overnight and through
much of the day on Wednesday. Scattered to numerous thunderstorms and rain will
develop Wednesday afternoon, and all terminals are likely to
report thunder at some point.
Prev discussion [325 PM edt]...
Short term [wednesday through Thursday night]...
In general, we'll remain under the eastern periphery of middle and
upper level ridging through the short term. At the surface, broad
low pressure will dominate.
Under the current ridge position, northerly steering flow will
advect any mesoscale convective vortex or mesoscale convective system from the east-central conus, south into the
tri-state region. The current thinking advertises some scattered
storms in our Georgia counties tomorrow morning, resulting from
convection ongoing over the Ohio and Tennessee valleys. Later in
the day, through the evening, a larger storm complex will likely
dive through the region. This round is most likely generated from
the remnant mesoscale convective vortex from convection in the upper Mississippi Valley
this afternoon. Essentially this means that the 8am - 12am period
Wed. Into thurs. Will be quite wet. This should also keep
afternoon highs in the lower to middle 90s.
On Thursday, the broad area of surface low pressure will center
itself closer to the tri-state region, increasing low-level
convergence. This will likely force widespread thunderstorms under
a more typical diurnal cycle. The widespread nature of storms will
most likely continue to keep high temperatures in the lower 90s.
Long term [friday through tuesday]...
Beginning Friday, the upper ridge moves a bit further east with
eastern Continental U.S. Troughing bulging into the southeast. At the same
time a surface front will settle into the region and stall. This
will keep rain chances above normal through the weekend. Early
next week a shortwave will dive into the southeast, keeping above
normal pops in the forecast. Afternoon highs will remain near, to
slightly below normal.
West/southwesterly winds will prevail through the next week and
will likely remain below headline levels. Shower and thunderstorms
are expected each day.
Hazardous fire weather conditions are not expected as we
transition back to a pattern of unseasonably high pops.
Rain chances will steadily increase as the week progresses. Five day
rain totals are estimated to be 3 to 4 inches near the Florida
coast, particularly The Big Bend. Elsewhere, 1 to 2 inches is
likely. Area rivers are still below action stage. With the heaviest
rainfall expected near the coast, river flooding is not expected.
Preliminary point temps/pops...
Tallahassee 77 93 78 89 77 / 10 60 40 50 30
Panama City 79 91 81 86 79 / 10 60 50 40 30
Dothan 76 94 76 90 77 / 10 60 30 40 30
Albany 76 94 76 91 76 / 20 60 30 40 30
Valdosta 75 92 77 90 76 / 10 50 30 50 30
Cross City 75 90 79 86 77 / 40 50 40 50 30
Apalachicola 79 89 80 85 80 / 10 50 50 50 30