Area forecast discussion
National Weather Service Birmingham Alabama
438 am CDT Wednesday may 22 2013
Discussion...
Very complicated forecast over the next 24 hours or so. Line of
thunderstorms that moved in from MS weakened significantly as they
approached the state line and entered Alabama as the outflow rushed out
ahead of the storms. In fact..the outflow was the main feature
Worth watching as it entered the County Warning Area. However the winds remained
well below severe criteria. The initial activity continues to
dissipate as additional development is now taking place across north
Alabama along the outflow boundary. Meanwhile a low stratus deck is
spreading northward across the southern counties and could lead
to some reductions in visible.
Actual cold front is still well back to our west across Arkansas. Expect
convection to initiate along and ahead of the front this morning
and then push east/southeast across central Alabama during the day with
frontal passage. Believe the best rain chances will remain
confined to the northwestern half of the County Warning Area. Coverage should
decrease through the evening with only a few isolated showers/storms in
the southeast counties by tonight. Will continue to leave mention of
severe out of the severe weather potential statement due to overall lack of atmospheric support
for anything more than perhaps a strong storm or two with gusty winds.
Another shortwave will rotate across the area on Thursday and
could lead to some isolated development...mainly in the afternoon. This
feature will usher in a much drier air mass from the north with
dew points falling into the 50s...and maybe upper 40s in the
north...by Friday. For those of you who are opposed to 90 degree
weather then you'll enjoy Friday. Temperatures will be below normal with
highs ranging from the middle 70s north to low/middle 80s south.
Surface high pressure will keep conditions dry through at least the
weekend with temperatures warming back into the middle/upper 80s by Sunday.
Still some questions regarding the setup early next week. Northwest flow
aloft usually spells trouble due to uncertainty in the tracks of
any upper level impulses. Due to model discrepancies will keep the
forecast dry in the extended for now.
&&
Aviation...
06z taf discussion.
Forecast thinking has not changed a whole lot since 00z issuance.
1st band died off in northern MS as gust front outran the storm and it
deteriorated to the NE. Still agree with model data that this 2nd
line will decrease as it moves east-northeast over the next couple of hours.
So...only have thunderstorms in the vicinity/vcsh later today with the front. Will be
closely monitoring storm activity on the chance that storms to not
decrease as anticipated and then amendments may be necessary.
There was a small line of thin activity that the 2nd line fed into
that gave it a boost. However...with that done...it should begin
to decrease shortly. Did bring convection up by a couple of hours
during the day with a slightly faster front...with convection now
by middle morning west just ahead of the front and with best chances
northern tafs. Some minor MVFR br out ahead of activity this morning
but cirrus blow off could curtail some of this.
08
&&
Preliminary point temps/pops...
Gadsden 83 63 83 57 77 / 50 30 20 10 0
Anniston 85 64 84 59 78 / 50 30 20 10 0
Birmingham 83 64 84 60 78 / 50 30 20 10 0
Tuscaloosa 84 63 87 61 81 / 60 30 20 10 0
Calera 84 65 84 60 80 / 50 30 20 10 0
Auburn 86 66 84 61 80 / 30 40 20 10 0
Montgomery 88 67 88 63 84 / 30 40 20 10 0
Troy 88 67 88 63 84 / 30 40 20 10 0
&&
Bmx watches/warnings/advisories...
none.
&&
$$
