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Area forecast discussion 
National Weather Service Birmingham Alabama
655 am CDT Sat Apr 25 2015

Update... aviation discussion.

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Discussion...

Short discussion this morning to only handle the short term.
Line of convection moving into western Alabama is moving into a
slightly more stable airmass. Dewpoints in western Alabama near
the state line just now reaching the lower 60s with a drop off
into the middle 50s at tcl. Surface based cape still non-existent
with mu cape between 100 to 250 j/kg. The really moisture rich air
is still just to the southwest of the County Warning Area. Shear values are
plentiful to support severe weather however...with 0-1km helicity
of 450+ and 0-6km bulk shear around 70 kts.

Over the next 1 to 3 hours...a very strong middle level
jet from the southwest is forecast to move into western Alabama
by the hrrr. We should see an increasing in precipitable water
with dewpoints rising into the middle and upper 60s and an increase
in the potential for surface based convection.

Still a lot of uncertainty with the potential re-development later
this afternoon. Looks like there might be a secondary middle level
speed maximum to develop over the County Warning Area by afternoon. Hi-res models do
respond with some redevelopment in the area so the potential for a
second round of severe weather still possible. Will see how the
current convection evolves through the early to middle morning and
update later for any changes.

88

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Aviation...
12z taf discussion.

At 12z...first wave of thunderstorms and rain will continue to move across east Alabama and
kmgm and ktoi through 1430z. Behind this system...lingering MVFR
ceilings will occur through 18z...with brief periods of IFR ceilings above
ground level in higher terrain sites like kanb and kasn. By
14z...southwest surface winds will pick up in intensity...along with
slowing breaks in clouds which will lead to mixing and ceilings rising
to VFR conditions around 18z. With main front still far to the
west...and approaching upper level dynamics...there is the potential
for thunderstorms and rain redevelopment after 18z. However...current thinking is
that activity will be too isolated to pinpoint at any taf site other
than thunderstorms in the vicinity. Stefkovich



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Preliminary point temps/pops...
Gadsden 78 62 79 51 72 / 90 30 10 10 0
Anniston 79 64 81 54 73 / 90 30 10 10 0
Birmingham 81 65 82 55 73 / 90 20 10 10 0
Tuscaloosa 83 65 84 56 75 / 60 10 10 10 10
Calera 81 65 83 56 74 / 80 20 10 10 10
Auburn 78 65 83 57 75 / 90 30 10 10 10
Montgomery 83 67 87 60 78 / 80 20 10 10 10
Troy 83 67 87 61 79 / 70 20 10 10 10

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Bmx watches/warnings/advisories...
none.
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