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Area forecast discussion 
National Weather Service Mobile Alabama
344 am CDT Wednesday Jul 30 2014

Short term (today and tonight)...the central Gulf Coast remains
under a northwest upper level flow pattern between an upper ridge to
the west and upper trough to the east. At the surface...high pressure
continues to build southeast toward the area. This will continue to
advect dry air across the area and maintain an unseasonably cool and
dry airmass. Temperatures will again be below normal for late July with
highs only in the upper 80s in most spots with low humidity levels.
Record low temperatures are possible yet again tonight with upper 50s
inland to upper 60s along the coast. /13

Records for July 31st

Mobile: 66/1984
pensacola: 67/1936

This afternoon's wet microburst risk: none

For Thursday through Friday night...the axis of the longwave trough
over the eastern states shifts west of the forecast area Thursday
into Thursday night and remains in this position through Friday
night. As this occurs...two features allow for increasing deep
layer moisture into the region...first a surface-850 mb low over
eastern Texas which advances rather slowly eastward to near the
Sabine River valley and a second less well defined surface-850 mb
low over the extreme northeast Gulf/Florida Peninsula which loses
identity while retrograding slowly westward. Added to this pattern
is a stationary front draped across the northern to central Gulf
between these two features which then lifts northward as the
northeastern Gulf low weakens and dissipates...moving to near the coast
late Friday night. Precipitable water values begin Thursday morning
a rather low 1-1.25 inches but increase quickly to 1.6-1.9 inches by
Thursday night then to around 2 inches by Friday night. Will have
dry conditions for most of the area Thursday except for small probability of precipitation
Thursday afternoon over the western third of the area where deep
layer moisture begins to increase first and a series of shortwaves
move through the upper trough. Mainly dry conditions follow for
Thursday night then chance probability of precipitation follow for most of the area on Friday
due to abundant deep layer moisture and support from a continuing
series of shortwaves moving across the region. Daytime highs will be
near seasonable values. Lows Thursday night will be about a few
degrees below normal then trend to seasonable values by Friday night.

Long term (saturday through tuesday)...the longwave 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


Marine...a light northerly flow will continue in the wake of the
cold front that moved through yesterday through Thursday. This will
maintain light winds and low seas through the end of the week.
Showers and thunderstorms return to the forecast late in the week
through early next week. /13


Aviation (12z issuance)...VFR conditions will prevail through the
next 24 hours. /13


Fire weather...relative humidity values will drop to around or just
below 30 percent this afternoon. While these relative humidity
values will drop briefly to near or just below critical levels over
south central and interior southwest Alabama this afternoon...winds
will remain below criteria and a red flag warning will not be
issued. Afternoon relative humidity values are expected to remain
above critical levels on Thursday and Friday. /29


Preliminary point temps/pops...
Mobile 88 64 91 68 91 / 00 05 10 10 30
Pensacola 88 68 91 72 91 / 00 05 05 10 20
Destin 87 70 90 73 90 / 00 05 05 10 20
Evergreen 88 59 91 66 91 / 00 05 10 10 30
Waynesboro 87 62 90 64 89 / 00 05 20 20 30
Camden 87 60 90 66 88 / 00 05 10 20 40
Crestview 91 59 92 65 92 / 00 05 05 10 30


Mob watches/warnings/advisories...


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