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Area forecast discussion 
National Weather Service Birmingham Alabama
353 am CDT Tuesday Aug 4 2015

Discussion...

Numerical and model guidance suggest that temperatures today will
be a degree or two warmer than yesterday..so today may be the
hottest day so far this year with 100 degrees likely at several
locations across the western and southern counties. The good news
is that humidity levels will be lower than normal due to drier air
aloft that will mix downward this afternoon. Heat indices will be
close to air temperatures. As low level winds become south and
southwest on Wednesday...moisture will begin to increase across
the area...but still precipitable water values will still be below
1.5 inches...so afternoon convection will be limited in areal
coverage. By Thursday afternoon precipitable water values will
approach 2 inches...and a short wave trough will pass to the north
of Alabama. This impulse will provide the needed lift for the
development of numerous showers and storms across north
Alabama...with lesser coverage across the south. The activity will
last well into the overnight hours Thursday night as the main lift
associated with the impulse sinks southward into north Alabama.
The models show a weaker upper impulse tracking southeast towards
Alabama on Friday...and will continue with above normal rain
chances.

By Saturday much drier middle level air advects southward behind the
exiting short wave trough. The European model (ecmwf) model does not show as much dry
air as the Canadian or GFS models...and kept a chance of rain as
far north as I-20. The drier air will continue to push southward
on Sunday and Monday...and the GFS keeps all the rain south of
central Alabama as it expands Texas Ridge eastward. The European model (ecmwf)
model does not expand the ridge like the GFS...and it has more
convection developing on the eastern periphery of the upper high.
Took a blend of the models with regards to rain chances and high
temperatures Sunday and Monday.

58/rose

&&

Aviation...
06z taf discussion.

VFR conditions will prevail through the period for most of the
area. Light MVFR fog is possible early Tuesday morning at
ktoi...where low level moisture is slightly greater.

87/Grantham



&&

Fire weather...

Light north winds today will result in above normal temperatures
and relative humidity values near 30 percent this afternoon across
central Alabama. Low level moisture will increase on Wednesday as
winds become southwest. Scattered to numerous showers and
thunderstorms by Thursday as a short wave trough passes through the
area. The better rain chances will shift into South Alabama by
the weekend.

&&

Preliminary point temps/pops...
Gadsden 97 72 95 72 89 / 10 10 30 30 60
Anniston 98 72 95 72 90 / 10 10 30 20 60
Birmingham 98 75 96 74 91 / 10 10 30 30 60
Tuscaloosa 100 74 98 73 92 / 10 10 30 30 50
Calera 97 72 95 71 90 / 10 10 30 20 50
Auburn 96 73 94 72 89 / 10 10 30 20 40
Montgomery 100 74 97 75 93 / 10 10 30 20 40
Troy 99 73 96 73 90 / 10 10 40 20 40

&&

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

$$

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