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afdbmx

Area forecast discussion
National Weather Service Birmingham Alabama
353 PM CDT Sat Aug 24 2019

Short term...
/updated at 0321 PM CDT Sat Aug 24 2019/
tonight through Sunday.

This afternoon we have a weak stationary boundary situated across
central Alabama from west to east. This boundary will likely
meander some through Sunday and continue to aide with convection
development. In the upper levels, we continue in a moist and active
pattern with an upper trough currently over the Texas and
Louisiana coast. Guidance carries this upper trough northeast
tonight into Sunday toward Mississippi with a continued feed of
moisture and ripples through this trough into central Alabama
through the weekend. We remain in a wet pattern with elevated 2+
model pwats to continue.

I only made a few tweaks the forecast grids for Sunday night
through Monday to inch up rain chances further as the upper
trough pushes toward Alabama and confidences increases. We remain
in a wet pattern through Tuesday. A front continues to be in the
works for mid week to bring lower rain chances for the latter half
of the week.

08

Long term...
/updated at 0300 am CDT Sat Aug 24 2019/
Sunday through Friday.

The extended forecast remains largely on track as the active and
rainy pattern continues through the first half of next week. With
the east to west oriented surface front decaying across northern and
central Alabama by early Sunday morning, shortwave troughing deepens
over the Mississippi Valley just to the west of the forecast area as
this feature, coupled with moist onshore flow, becomes the key
factor in initiating convection during the afternoon. Hi-res
guidance depicts widespread showers and storms initially developing
in the southwest before spreading northward during the day. Expect
to see widespread coverage consistent with previous days activity
and influenced by any outflow boundaries left lingering across
central Alabama overnight. Pre-frontal troughing becomes well
pronounced over Alabama by Monday with yet another day of likely to
widespread showers and storms expected. Pwats will remain near 2.0
inches such that any slow-moving thunderstorm will need continued
monitoring for localized flooding, especially in our drought
stricken areas where soils have become hard and dry and heavy
rainfall may initially runoff. This issue should become less evident
through the week as soil moisture returns to normal levels with
continued rain chances providing some drought relief. Temperatures
are forecast to remain below 90f on Monday with highs in the upper
80s as widespread rain and cloud cover keeps US a bit cooler but
humid.

We could see a touch of dry mid-level air move in behind the
shortwave trough on Tuesday with a weak low-level ridge helping to
further limit rain coverage, but this should be short lived with
rain chances increasing late Tuesday afternoon as a cold front
quickly approaches the forecast area from the northwest. Frontal
passage is expected on Wednesday as the associated upper-level
trough and low height center continues to rotate eastward over
Ontario and Hudson Bay. A much drier airmass will move in during the
day Wednesday where highest rain chances will be focused along and
southeast of I-20. Plentiful sunshine returns for the end of the
work week with highs in the upper 80s/low 90s and overnight lows in
the mid/upper 60s.

86

&&

Aviation...
18z taf discussion.

Cloud cover is more widespread across our southern sites with
developing cumulus over our northern sites. Have started with thunderstorms in the vicinity
at tcl/eet with a few ts between the two terminals. Other sites
are staring with vcsh followed by thunderstorms in the vicinity by mid afternoon. Expect
convection to persist through early evening followed by scattered
clouds overnight. Some reduction in visibility is expected at most
sites early Sunday morning before sunrise, persisting until mid
morning.

05

&&

Fire weather...

Shower and thunderstorm chances remain elevated through Tuesday as
we remain in a moist tropical airmass. With the increased
moisture, minimum relative humidity values will be elevated as
well. Gusty winds will be possible in close proximity to any
thunderstorms that do develop. A surface frontal boundary is
expected to move through Wednesday into Thursday. Although drier
air will arrive, minimum relative humidity values for the end of
the week should still remain above critical levels.

&&

Preliminary point temps/pops...
Gadsden 70 83 68 83 68 / 70 60 70 80 50
Anniston 71 82 70 84 70 / 70 60 70 80 50
Birmingham 72 86 71 86 72 / 60 70 80 80 40
Tuscaloosa 73 88 72 86 72 / 40 80 80 80 30
Calera 72 86 70 85 70 / 50 80 80 80 40
Auburn 71 84 71 84 70 / 60 60 70 80 50
Montgomery 74 89 72 87 72 / 40 80 80 80 50
Troy 72 88 71 86 70 / 50 70 60 80 50

&&

Bmx watches/warnings/advisories/...
none.

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