Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Birmingham Alabama
607 PM CST Thursday Nov 26 2015
for 00z aviation.
Short term (tonight through friday)...
Tight surface pressure gradients have kept the east/southeast
winds up once again today. Once again...some of the elevated
winds will carry over past sunset into the overnight hours...but
not as gusty as during the daytime. With a slowly retreating
elongated surface ridge...the resulting low level flow has been
slow to turn...but is eventually expected to do so. With dew
points finally rising some as well today think that we should get
some overnight stratus to finally develop tonight during at the
very least the late night hours from east-northeast to
south/southwest around the back side. Overnight lows are
expected to be a few degrees milder for tonight once again with
the elevated winds and incoming cloud cover to slow the cooling.
High temperatures on Friday during the day should be similar as
today. Although we are expecting cloud cover...that should become
more scattered as the morning progresses with mixing. Also...we
will be starting milder than this morning. All in all... Friday
should be another nice one as the rain chances should hold off for
all central Alabama until later over the weekend.
Long term (friday night through thursday)...
Quiet and mild weather will continue Friday night into Saturday
with an upper-level ridge in place across the Gulf of Mexico and
deep south. Cannot rule out a few showers clipping our northwest
counties on Saturday...but the main area of rain should remain
confined to a frontal zone to our northwest.
Advancement of the front and rain will be rather slow as a large
closed upper low wobbles around over the western Continental U.S.. a
weakening upper-level ridge will allow the surface front to make
a bit of eastward progress late Sunday into Monday...with
increasing rain chances mainly north of Interstate 20. As the
trough out west finally begins to move eastward...the front will
more than likely become stationary as the best upper-level support
shifts back to the northwest. This will keep the highest rain
chances across the north and west once again for Tuesday. The
cold front will finally push through Tuesday night into Wednesday
as the upper trough moves more rapidly eastward across the Great
Lakes region...with cooler and drier conditions to follow.
00z taf discussion.
Very similar setup to last night across central Alabama. No clouds
developed at all last night while all MOS develops them again
tonight. Kept the mention of MVFR ceilings for a few hours around
sunrise...but confidence is lacking and reduced the mention to
tempo at this time. Not seeing a huge increase increase in moisture
content. Precipitation water, mixing ratios, specific humidities all
indicate little change. Isentropic lift is weak at best. But there
is a small possibility that some lower clouds may develop and
enter the picture more toward 12z. Winds will keep a light
easterly component overnight and become southeast around 9kts on
Mild and dry conditions for much of the area through Saturday.
Rain chances will arrive Saturday night in the extreme northwest
part of the state...expanding slowly through all of central
Alabama on Sunday and Monday. There are no fire weather concerns.
Preliminary point temps/pops...
Gadsden 52 68 49 70 51 / 0 0 0 10 10
Anniston 53 68 49 70 50 / 0 0 0 0 10
Birmingham 55 69 53 71 54 / 0 0 0 0 10
Tuscaloosa 56 72 54 72 54 / 0 0 0 0 10
Calera 55 71 53 71 54 / 0 0 0 0 10
Auburn 54 69 52 72 52 / 0 0 0 0 0
Montgomery 55 73 52 75 51 / 0 0 0 0 0
Troy 56 73 52 74 51 / 0 0 0 0 0