Area Forecast Discussion
Issued by NWS Birmingham, AL
FXUS64 KBMX 301120
Area Forecast Discussion
National Weather Service Birmingham AL
620 AM CDT SAT JUL 30 2016
For 12Z Aviation.
The base of a broad upper trough is in place across the region
with weak cyclonic curvature at 500mb. Deep moisture and daytime
heating should lead to scattered showers and storms particularly
during the afternoon with highs in the 88-95F range. This activity
will gradually diminish during the evening hours.
Sunday through Saturday, the westerly flow aloft transitions to a
northerly flow. This shift is due to the mean trough moving to the
east coast and the ridge center building over the plains. Even with
the shift, the overall flow remains rather light and temperatures
aloft rather warm. A few short waves move through the flow but
these will provide only weak lift and the models are differing on
the exact timing. The surface ridge remains off to our east
providing a general southerly low level flow. Precipitable water
values remain 1.80 inches or higher much of the period with
surface dew points in the 70s. Therefore, kept the forecast trend
of near climatology pops going. There may be a period or two of
higher activity but this will be due to mesoscale or smaller
scales and will need to be ironed out as we go. High temperatures
in the mid 90s are supported by low level thickness and 850 temps
but there will be low level moisture and clouds. Bumped temps a
tad but generally low to mid 90s. This keeps the heat indices in
the 100 to 105 degree range. Model advertised thermodynamic
profiles do not indicate anything great for strong to severe
thunderstorms. Moisture content and relatively light winds through
the layer may allow a few heavy downpours but wind gust should be
below 40 mph, at least for now.
12Z TAF Discussion.
VFR cigs are expected through the next 24 hours. Scattered showers
and storms are expected during the afternoon and early evening
with VCTS indicated at all sites. Any impacts should be relatively
short-lived with easterly storm motions of 15-20 kts.
Generally scattered showers and thunderstorms are expected over
the next several days with highs in the upper 80s and low/mid 90s.
Surface winds will be less than 10 mph and generally from the
southwest/west through the weekend. Since surface dew points are
so high, critical fire weather thresholds are not expected to be
met, with no watches or warnings anticipated.
.PRELIMINARY POINT TEMPS/POPS...
Gadsden 90 72 92 71 92 / 40 40 40 30 40
Anniston 91 73 93 72 93 / 40 40 40 30 40
Birmingham 91 76 93 74 93 / 40 40 40 30 40
Tuscaloosa 92 74 94 73 94 / 40 40 40 30 40
Calera 92 74 93 73 93 / 40 40 40 30 50
Auburn 91 74 93 74 93 / 40 40 40 30 50
Montgomery 94 75 95 74 94 / 40 40 40 40 50
Troy 92 73 92 72 92 / 40 40 40 40 50