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Area forecast discussion 
National Weather Service Mobile Alabama
1158 PM CDT Thursday Jul 28 2016

Discussion...updated for latest aviation discussion below.


06z issuance...satellite shows high level cirrus over the area. Cigs
and vsby forecast at VFR categories. Light west to southwest winds
less than 5 kts overnight. /10


Previous discussion... /issued 836 PM CDT Thursday Jul 28 2016/

Discussion...see updated information for land areas below. maps this evening show a persistent deep layer
ridge in place off the southeast US coast, which extends westward to
the central Gulf Coast. A break in the ridge is positioned from the
Tennessee River valley, southward to across la. Within the weakness and
upper level shear zone, deep layer moisture remains high with pwats ~
2 inches along with lingering evening instability (mu cape =>
1000-2000 j/kg). This is where radar has shown isolated/scattered
showers and storms tracking off to the northeast this evening,
generally to the west of I-65. As this activity produces rain-cooled
outflow boundaries, forecasters are seeing little in additional
development as outflows, in essence, work to stabilize the local

Further to the south, out over the al/northwest Florida coastal waters, starting
to see some isolated showers popping up and am considering going from
the current 10% chances there up to 20%. Will continue to monitor
trends a bit longer before making any adjustments in these areas.
Overnight forecast lows OK. /10

Previous discussion... /issued 628 PM CDT Thursday Jul 28 2016/

Discussion...updated for latest aviation discussion below.

00z issuance...radar shows isolated to scattered shra/tsra over
interior southeast MS and southwest Alabama this evening, tracking to the
northeast. There has been very little development eastward and with
the expectation that activity to the northwest of the terminals will
begin to decrease heading into the evening, will keep mention of
convection out of the 29.00z taf package tonight. VFR cigs/vsby
forecast with south southwest flow trending to less than 5 kts
overnight. /10

Previous discussion... /issued 353 PM CDT Thursday Jul 28 2016/

Near term /now through Friday/...deep south to southwest flow will
continue to allow plenty of low to mid level moisture to advect
northward over the central Gulf states through Fri afternoon as sfc
to upper ridge continues to build in from the east...combined with a
weak mid to upper trof of low pres over the lower to mid River
Valley lifting northward through Fri afternoon. This pattern will
continue to lead to isolated to scattered showers and thunderstorms
to form mostly over inland areas of the forecast area this afternoon
and early tonight...reforming near the coast and offshore early
tomorrow...then shifting inland during the late morning and
afternoon hours. For the rest of today most of the coverage looks to
remain well inland from the coast...generally along and north of the
I-10 corridor...continuing through early this evening then
dissipating quickly as daytime heating is lost. For Fri morning
isolated showers and thunderstorms are expected to form very early
offshore and near the coast followed by better coverage over inland
areas mostly to the west spreading eastward during the afternoon and
early evening hours. With slightly higher moisture content by Fri
combined with slightly warmer surface temps...highs in the mid 90s
for most inland areas...leading to better instability during the
day...also combined with slightly better mid level forcing due to
passing shortwave to the northwest...daytime coverage of showers and
thunderstorms will be a tad higher on Fri compared to today. Model
soundings do show some dryness aloft combined with marginal mid to
upper lapse rates in the boundary layer suggesting most of the
thunderstorms by mid to late afternoon will remain below severe
limits with maybe a few strong to marginally severe with straight
line winds and frequent lightning being the main concerns. As for
temps lows tonight will continue to range in the mid 70s inland and
the upper 70s to lower 80s near the coast...with highs in the mid
90s for most inland areas...lower 90s near the coast with heat
indices ranging from 100 to 103 degrees for most areas during the
late morning and afternoon hours. 32/ee

Short term /Friday night through Sunday night/ upper trof
extending from the Great Lakes region to near the Sabine River
valley weakens while advancing slowly eastward through Sunday night,
with upper ridging gradually strengthening over the Gulf Coast
states. A series of modest shortwaves move across the region, through
the weakening upper trof pattern, while deep layer moisture remains
high, with precipitable water values near 2.0 inches. A surface ridge
persists over the northern Gulf and promotes an onshore flow, along
with the occasional presence of a subtle surface trof over the Gulf
Coast states, and expect scattered convective development each day.
Highs each day will range from the mid 90s inland to near 90 at the
coast, with heat indices of 101-106 each afternoon. Lows will be
mostly in the lower/mid 70s except for upper 70s/near 80 at the
coast. /29

Long term /Monday through Thursday/ upper trof over the
interior eastern states moves off into the Atlantic through the
period, with upper ridging building into the region. A surface ridge
persists over the northern Gulf through the period and maintains a
moist southerly flow over the area, while a weak transient surface
trof lingers over the Gulf Coast states. Expect a continuation of
scattered convection developing each day with this pattern. Highs
will be in the lower/mid 90s with heat indices of 100-106 each day.
Lows will range from the mid 70s inland to the upper 70s near the
coast. /29

Marine...deep high pressure will continue to build in from the east
through early next week leading to a light to moderate south to
southwest wind flow mostly during the day and evening hours through
Tue...with a slight shift to the west northwest mostly along the
coast during the overnight and early morning hours. Seas will
continue to range from 1 to 2 feet offshore with smooth to light
chop conditions on area bays and sounds...with better winds and
waves occurring over the near shore waters during the afternoon and
evening hours due to daytime heating and local seabreeze effects.
Isolated to scattered showers and thunderstorms will also continue
in the forecast through early next week with better coverage
offshore and near the coast early in the day with maybe a few
stronger thunderstoms moving in from the west northwest by late
afternoon each day. 32/ee


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