Scientific Forecaster Discussion
fxus64 kbmx 251201
Area forecast discussion
National Weather Service Birmingham Alabama
601 am CST Sat Nov 25 2017
for 12z aviation.
Today and tonight.
Look for increasing clouds during the afternoon as a cold front will
slide through the area. Not expecting any rain from the front as it
does remain fairly dry out there. Latest models are hinting at maybe
some sprinkles at best in the north after 1 PM, so went ahead and
included occasional sprinkles generally north of a Birmingham to
Anniston line. Clearing skies tonight and cool temperatures will be
in place once again as a dry airmass works into the region.
Sunday through Friday.
The large scale weather pattern through the long term portion of
the forecast will be a tendency toward upper level troughiness in
the eastern half of the County. This will largely keep the Gulf
moisture source shut off, and rain chances to a minimum.
Having said that, there is a slight deviation from this big
picture idea in the middle of the week. The pattern briefly GOES
more zonal, allowing a mid-level shortwave trough to zip across
the southern portion of the country...affecting Alabama on
Wednesday. Passage of this trough will likely be accompanied by
another period of cloudiness and some showers. Another, more
latitudinally developed, trough then follows quickly behind the
first trough. This second shortwave will help drive the next cold
front through our area by the end of the week. Since the front and
associated shortwave trough follow so closely behind the lead
shortwave, it appears there is no time for destabilization ahead
of it/them. Will maintain chance of showers (no thunderstorms, as
of yet) until the next push of dry air comes in on Friday.
All in all, nothing too extreme in the extended forecast. That
could change further down the Road, as the models suggest an upper
level ridge developing along the Gulf Coast early next week, which
could lead to warmer than normal temps. But that is beyond the
scope of this forecast period for now.
12z taf discussion.
Starting with high clouds north and patchy fg south. This will
give way to mid level clouds today and possibly a sprinkle at
anb/asn this afternoon as a cold front passes through. Clearing
skies this evening as a dry airmass works in. Fog should not be an
impact overnight as the airmass will be much drier.
The forecast features overall dry conditions and near normal
temperatures through the weekend and into early next week. A few
sprinkles can not be ruled out this afternoon across the far north
but accumulations are not expected. There are no fire weather
concerns at this time.
Preliminary point temps/pops...
Gadsden 66 35 60 32 61 / 10 0 0 0 0
Anniston 67 36 59 35 62 / 10 0 0 0 0
Birmingham 65 38 61 36 62 / 10 0 0 0 0
Tuscaloosa 67 39 63 35 64 / 10 0 0 0 0
Calera 65 39 63 35 63 / 10 0 0 0 0
Auburn 68 41 59 39 63 / 0 0 0 0 0
Montgomery 68 40 63 36 64 / 0 0 0 0 0
Troy 70 40 63 37 65 / 0 0 0 0 0