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Area forecast discussion 
National Weather Service Mobile Alabama
936 PM CDT Wednesday Jul 30 2014

Mesoscale update...no changes needed. Radar is free of returns except
for some weak returns coming from high clouds well north of the County Warning Area.
Suspect these returns indicate virga. Over the Gulf there are some
even weaker returns from clouds suspect as not precipitating at all.

Temperature is dropping a little slowly as it did last night but with
clea skies and wind at a dead calm...it should see a precipitous drop
within the next few hours.

77/blowing dust

&&

Previous discussion... /issued 640 PM CDT Wednesday Jul 30 2014/

Aviation update for 31... conditions are expected
through the next 24 hours region wide. Light north winds.

77/blowing dust

Previous discussion... /issued 338 PM CDT Wednesday Jul 30 2014/

Short term...(tonight through Friday night)...tonight through
Thursday...with an unseasonably dry airmass in place and clear skies
to begin the night...another night of below normal and near record
temperatures is expected. The only fly in the ointment to the
forecast is increasing middle and high level clouds ahead of a shortwave
moving into the lower MS valley late tonight. At this point...it
appears that we will see scattered high clouds moving in later this
evening from the west...with the potential of thicker cloud cover
moving into southeast MS by daybreak Thursday. If this evolution
holds true...clouds will not impact lows all that much...except for
maybe a few degrees warmer in southeast MS. However...if cloud cover
increases quicker than expected...low temperatures may be several degrees
warmer than guidance. At this point...will stick close to the
previous forecast and show near record temperatures in the upper 50s well
inland with low to middle 60s along the I-10 corridor and upper 60s at
the beaches. Here are the record lows for Thursday morning...

Records for July 31st

Mobile: 66/1984
pensacola: 67/1936

Middle and high level clouds will increase further on Thursday with
many areas likely seeing periods of mostly cloudy skies. Despite
shortwave activity moving across north central al/MS...residual low
level dry air will keep rain chances low. Cannot rule out a few
sprinkles over southeast MS...but no measurable rain is expected at this
point. Went a few degrees below mav guidance for high temperatures...which
yields upper 80s/lower 90s instead of low to middle 90s as the mav
suggests. 34/jfb

Thursday night...as shortwave energy north of the forecast area swings away in
the upper trough over the eastern Continental U.S. Trough...the surface boundary
across the forecast area draws back north...allowing deeper moisture to move in
from the west. Looking at the model soundings...this is mostly in the
middle/upper levels...leaving a dry layer in the lowest 10k' feet of the
atmosphere. Temperatures again below seasonal...though with the increase in
cloud cover...not quite as cool as previous days.

Friday...more upper energy begins to move into the eastern upper
trough...but stays far enough away from the forecast area to be a non-factor in
the weather. The day does warm enough to form a weak-heat induced
surface low over the forecast area. With temperatures at or a skosh above seasonal...I
believe it.

Friday night...the upper energy moves farther into the eastern
trough...becoming close enough for precipitation to move towards or over
northern regions of the forecast area by Saturday morning. The forecast area remains under a
weak surface trough...but not quite enough for precipitation formation over
most of the forecast area. Temperatures around to a bit below seasonal due tot he
increased cloud cover of the approaching system.

Long term...(saturday on)...the long-wave trough over the
eastern states weakens while advancing slowly eastward through the
period to a weak upper trough over the region by Tuesday. The
surface-850 mb low near the Sabine River valley makes little
progress eastward before dissipating Saturday afternoon while the
frontal boundary near the coast is expected to move inland then dissipate
by Saturday night. The surface pattern over the region for the
remainder of the period looks to be a roughly convergent flow between
a surface high advancing from the plains into the eastern states and
a large surface high dominating the western Atlantic. Abundant deep
layer moisture remains over the region through Sunday then trends
lower Monday into Tuesday to slightly below seasonable values as the
weakening upper trough advances slowly eastward. Have stayed with
chance to good chance probability of precipitation through Monday then chance to slight
chance probability of precipitation follow for Tuesday with the decreasing deep layer
moisture. Temperatures will be near or slightly below seasonable
values. /29

Aviation...
(18z issuance)...VFR conditions are expected through the
next 24 hours. 34/jfb

Marine...high pressure over the lower Mississippi Valley will
weaken by Thursday. A weak trough will develop over the region by
the end of the week into the weekend...however the pressure gradient
will be weak...resulting in light winds and lows seas. A chance of
showers and thunderstorms return to the forecast late in the week
through early next week. 34/jfb

&&

Preliminary point temps/pops...
Mobile 63 90 68 91 71 / 00 10 10 30 20
Pensacola 67 90 71 91 73 / 00 05 10 30 20
Destin 70 89 73 90 76 / 00 05 10 30 20
Evergreen 58 90 65 92 71 / 00 05 10 30 30
Waynesboro 61 89 62 90 68 / 00 10 20 30 30
Camden 59 89 65 91 70 / 00 10 20 40 30
Crestview 56 92 64 92 71 / 00 05 10 30 20

&&

Mob watches/warnings/advisories...
Alabama...none.
Florida...none.
MS...none.
GM...none.
&&

$$

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