Area Forecast Discussion
Issued by NWS Birmingham, AL
FXUS64 KBMX 241159
Area Forecast Discussion
National Weather Service Birmingham AL
659 AM CDT WED AUG 24 2016
For 12Z Aviation.
Today and Tonight.
Mostly clear skies early this morning per the latest Fog Satellite
Product. It appears there will be lesser dew point depressions
near the Georgia state line and will leave the mention of some
patchy fog far east. Additionally, some clouds will also develop
in this same area. If fog develops, it will dissipate quickly by
8 am and the clouds will also slowly decrease through the morning
Tricky little forecast for this afternoon. The models are in good
agreement that the upper level ridge builds to 596-597dam and
centered just immediately to our west. Therefore, lesser
convection the farther northwest you go. It appears that an
outflow from the convection in the far southeast yesterday has
pushed to near the spine of central Alabama terrain differences
and oriented northeast to southwest. Hi-Res models are indicating
lesser lower level convergence and lesser importance of any other
boundaries that would provide some focus for convection. A very
weak vorticity axis rides around the periphery of the ridge but is
weak. Will keep the rain chances oriented northeast to southwest
over the area with slightly lesser pops than advertised yesterday
but also extended just a tad farther northwest into the Birmingham
metro for scattered activity. Once again, soundings do not
indicate the potential of anything beyond a general thunderstorm
and this is further enhanced by the lower overall convergence and
lack of a significant gradient in mass fields moving in from the
Any convection that does develop will wane quickly after sunset
with skies becoming mostly clear. Highs will generally be in the
90s and lows in the 70s.
Thursday through Tuesday.
A sprawling upper ridge will be located to our north on Thursday
with much drier deep-layer easterly flow over Alabama. Rain chances
will be almost non-existent in this pattern which will continue
through at least Saturday.
Uncertainty begins to creep into the forecast on Sunday with models
indicating a surge of Atlantic moisture moving westward into the
southern half of GA/AL. With the upper-level ridge expected to move
toward Mid-Atlantic states, deep-layer flow may acquire a more
southerly component. This may open the door for higher rain chances
on Sunday into Monday particularly in the southern counties.
Around this same time a tropical system may also have implications
on our weather especially if it actually develops over the next few
days and moves toward the Gulf of Mexico. There is huge uncertainty
regarding the development and track of disturbance which is
currently located near Puerto Rico. In the 120-168 hour range,
models show very weak 500mb flow across the entire Southern CONUS
which probably means we`ll continue to see wildly inconsistent
model solutions for the next few days.
12Z TAF Discussion.
The forecast will contain VFR conditions this period. Mostly clear
conditions start the morning but there is some patchy ground fog
out there. The fog is not affecting many locations and do not
anticipate it moving into any of the terminals. Low level moisture
will combine with the heating of the day and produce a cumulus
field by afternoon.
The focus for convection appears a bit lower than previous
forecast. An upper level ridge builds to the northwest of the area
today and easterly surface flow takes over. Maintained the prob30
for thunderstorms late this afternoon between 2100 and 2300 for
all terminals. Becoming mostly clear with some easterly flow
Isolated/scattered showers and storms are possible today as
easterly flow increases over the area. A prolonged period of
generally dry conditions may begin Thursday and continue into the
weekend. Critical fire weather conditions are not expected.
.PRELIMINARY POINT TEMPS/POPS...
Gadsden 91 71 93 71 93 / 40 20 10 10 20
Anniston 91 72 93 71 92 / 40 20 10 10 10
Birmingham 93 75 94 74 94 / 40 20 10 10 20
Tuscaloosa 95 74 95 74 95 / 30 20 20 10 20
Calera 93 73 93 73 94 / 40 20 10 10 10
Auburn 91 72 92 71 93 / 40 10 10 10 10
Montgomery 95 74 95 73 95 / 40 20 10 10 10
Troy 93 72 93 71 93 / 40 10 10 10 10