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Area forecast discussion
National Weather Service Birmingham Alabama
420 PM CDT Mon may 22 2017

Short term...
tonight into Tuesday.

A surface frontal system across the southeast portions of central
Alabama is expected to drift some back to the northwest closer to
the I-20/59 corridor tonight and likely stall until Tuesday when
another frontal system approaches the state. In the upper levels,
the main low is currently digging southward from central Canada
into Minnesota tonight and into Iowa on Tuesday. Across central
Alabama, we have southwest flow in the upper levels around the
main low with numerous short wave perturbations moving through
this tight flow from now into tonight and Tuesday. With dew
points remaining lower to the north of the surface front but
elevated overall, we will continue with a moist atmosphere to
feed the upper level waves as well as a focus with the meandering
front. This will aide in continued rain showers along with some
thunder at times to transverse across the area. Rain will be off
and on through the period with some heavy rain at times. The
highest total amounts continue to be expected across the southeast
1/3 of the area to the south of the surface front, and thus we
continue to have the Flash Flood Watch in effect for tonight into
Tuesday.

Temperatures will be rain cooled for tonight and a little lower
across the northwest behind the front. However, the southwest
upper flow is not allowing any real cold air advection into the
area. During the day on Tuesday, look for cooler highs due to the
widespread precipitation expected.

08

Long term...
Tuesday night through Sunday.

Wave #3 will be the main upper-level trough axis, anomalously deep
for late may, and will be accompanied by a seasonably strong cold
front. Shear, forcing, and cooling aloft will all be impressive
with this system. However, moisture quality/instability is very
much in doubt as it will be coming in very quickly behind the
previous system (and trending quicker), with some models
especially the European model (ecmwf) indicating westerly/northwesterly low-level
flow ahead of it and only low 60s dew points. Expect the dynamics
to be enough for a fast- moving line of showers and storms
Tuesday night and Wednesday, some strong with gusty winds and
hail. However, not confident enough that convection will be strong
enough to produce severe winds/hail to mention anything in the
severe weather potential statement. Rainfall amounts should also be lighter with this system as
well. Light rain/drizzle will linger Wednesday afternoon/evening
behind the front due to the cold core aloft, and refreshingly
cooler air will move in. The cool down won't last very long, with
warmer temperatures and some shower/storm chances returning by the
weekend in west-southwest flow ahead of a trough moving through
the northern tier.

32/Davis

&&

Aviation...
18z taf discussion.

Rain showers with isolated thunderstorms and rain will continue to affect asn/anb and east
as a disturbance slides further east of the area. Another
disturbance will approach the area from the west this afternoon.
Expect isolated rain showers/thunderstorms and rain this afternoon with increasing coverage
this evening through the overnight hours followed by a gradual
decrease in coverage later in the day on Tuesday. Ceilings will fall
from MVFR early this afternoon to IFR overnight and into early
Tuesday.

05

&&

Fire weather...

Several rounds of heavy rain and storms are expected now and
continuing through mid week. Another 2 to 3 inches of rainfall are
possible across the southern portions of central Alabama by
Wednesday. Therefore, critical fire weather conditions will not
occur.

&&

Preliminary point temps/pops...
Gadsden 62 76 61 72 53 / 90 70 70 60 30
Anniston 64 77 62 74 54 / 100 80 60 60 20
Birmingham 64 77 63 72 55 / 100 70 60 60 20
Tuscaloosa 62 79 62 73 54 / 100 70 60 50 20
Calera 64 78 62 73 55 / 100 80 60 60 20
Auburn 65 77 64 74 56 / 100 80 60 60 20
Montgomery 67 80 66 77 56 / 100 80 60 60 20
Troy 66 78 65 76 56 / 90 80 70 60 20

&&

Bmx watches/warnings/advisories/...
Flash Flood Watch through Tuesday evening for the following
counties: Autauga...Barbour...Bibb...Bullock...Chambers...
Chilton...Clay...Coosa...Dallas...Elmore...Greene...Hale...Lee...
Lowndes...Macon...Marengo...Montgomery...Perry...Pike...
Randolph...Russell...Sumter...Tallapoosa.

&&

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