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Area forecast discussion 
National Weather Service Birmingham Alabama
333 am CDT Wednesday Apr 16 2014

Discussion...

Surface high pressure to the north is keeping northerly winds across
central Alabama. Winds have picked up a few knots over the last
couple of hours...so temperatures have not fallen as quickly as
previously thought. Most locations are still in the upper
30s...with our usual cooler spots already below freezing. Temperatures
are expected to fall a few more degrees...but with the
winds...widespread frost is not anticipated...except for at
sheltered locations. Temperatures should rebound nicely into the
60s today. The high pressure will shift to the east through the
day...with winds becoming more easterly by the overnight hours.

Moisture will increase slightly...though not much...by Thursday
afternoon in advance of the next system to affect central Alabama.
An upper level trough will move east of The Rockies and to the north
of central Alabama during the overnight hours on Friday and through
the day. A shortwave will develop along the base of the broad trough
in the northern Gulf of Mexico. As this shortwave moves to the
east...it will amplify...bringing an abundance of moisture and
convection along the Gulf Coast. Models are in fairly good agreement
with the placement of this shortwave...with varying strengths
between models. With the amount of convection along the coast...and
the easterly winds across our area...moisture will be limited and
therefore precipitation amounts should be low...and rain converge
will be minimal as well. Therefore...did not make any changes to the
previous pop forecast of chance probability of precipitation. The shortwave will move to the
east...with surface high pressure and upper level ridging producing
nice conditions across central Alabama over the weekend.

By the Sunday timeframe...models diverge in their solutions...with
little to no agreement among models. Southerly flow will bring an
increase in moisture during the day Sunday. The GFS brings an upper
level trough and a slow moving cold front through the plains on
Sunday and Monday...with several disturbances moving through central
Alabama ahead of the main system. Rain continues through Monday and
Tuesday morning...before the cold front finally sags south of the
area. Meanwhile...the European model (ecmwf) keeps high pressure across the
area...with the trough moving through roughly 24 hours after the
GFS. With the high discrepancies...did not increase probability of precipitation for the
extended period. Temperatures should be nice through the
period...with normal to above normal readings across the area.

73

&&

Aviation...
06z taf discussion.

VFR for the next 24 hours with only the winds as the changing
factor as pressure gradients change with the building of the
surface ridge over the eastern United States. Northerly winds
will stay up at a few locations a tad more than normal for
remainder of the overnight hours. As the ridge shifts on Wednesday
to the east...winds will respond by becoming more
east/southeasterly during the day.

Note...the National Weather Service will be issuing seasonal
terminal forecasts for the Talladega Municipal Airport (kasn) in
Talladega...Alabama. The forecasts will be issued from April 20th
00z through at least may 8th 00z. Due to the limited availability
of observations...kasn taf will have amend not schedule appended to the
end of the forecast.

08/mk



&&

Preliminary point temps/pops...
Gadsden 60 38 64 47 67 / 0 0 10 20 30
Anniston 62 38 64 49 69 / 0 0 10 20 30
Birmingham 64 40 64 50 69 / 0 0 10 20 30
Tuscaloosa 65 40 67 52 71 / 0 0 10 30 40
Calera 63 42 65 51 69 / 0 0 10 20 30
Auburn 63 39 63 49 67 / 0 10 10 20 30
Montgomery 65 43 67 53 70 / 0 10 10 30 30
Troy 65 41 68 53 69 / 0 10 10 30 40

&&

Bmx watches/warnings/advisories...
freeze warning until 8 am CDT this morning for all of central
Alabama.

&&

$$