Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Birmingham Alabama
645 PM CDT Thursday Oct 8 2015
Short term...today through Friday.
Isolated to scattered showers...and a few storms...will continue
across northwest portions of the forecast area this afternoon in
conjunction with a corridor of weak convergence and slightly higher
moisture. Convection should diminish this evening with the loss of
daytime heating. Middle/high cloud cover will persist overnight...
primarily across the northern half of the state. Locations across
the south where cloud cover is expected to be less could see some
patchy fog overnight.
An upper level shortwave will cross the Midwest tonight and push a
frontal boundary southward into the southeast states on Friday with
rain chances increasing ahead of the front. Isolated to scattered
showers and thunderstorms are expected across much of central
Alabama with the best chances north of Interstate 20. With the surface
low way up in New England and lack of more significant upper level
dynamics no severe weather is expected.
Long term...Friday night through Thursday.
During the evening hours Friday night...will see the front
continue to make progress through central Alabama. The surface
system should make it through the County Warning Area well before morning.
However...some lingering showers will remain possible in the late
night hours Friday into the daytime hours on Saturday due to the
slower passage of the upper trough behind it. Rainfall amounts
will mostly likely be light but at the very least may keep clouds
lingering behind the front for a bit. This will keep temperatures
Friday night from cooling as quickly and on the flip side from
warming up as much on Saturday.
Surface ridging will keep US dry on Sunday behind the upper
trough. Although the low level flow begins to turn around early
on Monday ahead of another front...precipitation should hold off
until Monday night as the upper flow will be conducive to March
the front through in a timely fashion with forcing being our only
chance at precipitation with this system's fast turn around. This
system makes a quick exit Tuesday with only low probability of precipitation south thanks
to the speedy flow ushering in cooler and drier air for Tuesday
night through the remainder of the forecast.
00z taf discussion.
A few isolated showers continue across northwest central Alabama
along a low level convergent zone...but activity is not expected to
impact any forecast terminals. Middle to high level cloud cover will
continue to increase across the area...particularly the northwest.
Where cloud cover is less...light patchy fog is possible late
tonight. A front will approach the area late Friday...and have added
rain showers late in the forecast period for bhm and tcl. Expect most of the
activity to spread across northern terminals after 10/00z.
A cold front pushing through the state on Friday and will bring a
chance of showers and an isolated thunderstorm. The best chances
will be across the north. Some lingering clouds and low rain
chances will continue into Saturday with an upper level system
behind the front. Ridging will create dry conditions for late
Saturday into Monday day when yet another front will bring rain
chances back for Monday night into Tuesday. Cooler and dry weather
will return for middle week behind this second front. Conditions are
not expected to become dry enough at any point over the next week
to warrant any fire weather concerns.
Preliminary point temps/pops...
Gadsden 61 81 58 73 50 / 10 40 70 30 10
Anniston 63 82 60 73 54 / 10 30 60 30 10
Birmingham 65 83 60 74 53 / 10 40 70 20 10
Tuscaloosa 65 84 60 76 50 / 20 30 50 10 0
Calera 64 83 61 75 53 / 10 20 50 20 10
Auburn 64 81 63 76 57 / 10 20 40 30 10
Montgomery 62 86 64 80 55 / 10 20 40 20 10
Troy 62 85 64 80 55 / 10 10 20 20 10