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Area forecast discussion...updated 
National Weather Service Mobile Alabama
1200 am CDT Monday Aug 31 2015

Aviation...
06z issuance...VFR conditions will continue for the next 24 hours.
Calm to light winds will switch to a light southeasterly flow midday
Monday into Monday afternoon. /29

&&

Previous discussion... /issued 937 PM CDT sun Aug 30 2015/

Update...have updated to remove probability of precipitation for the remainder of the night
as the isolated convection has dissipated. No other major changes.
/29

Previous discussion... /issued 733 PM CDT sun Aug 30 2015/

Update...a few showers and thunderstorms have developed on a weak
sea breeze boundary slowly pushing northward across extreme
southwestern Alabama and a small portion of the interior northwest
Florida Panhandle. Have added slight chance probability of precipitation for this portion
for the remainder of the evening hours. Made other minor adjustments.
/29

Previous discussion... /issued 627 PM CDT sun Aug 30 2015/

Aviation...
00z issuance...VFR conditions continue for the next 24 hours with
a light northerly flow developing tonight then switching to a
southerly flow near 5-8 knots by midday Monday. /29

Previous discussion... /issued 401 PM CDT sun Aug 30 2015/

Short term [tonight through Tuesday night]...for tonight through
Monday...water vapor imagery showing the upper low that has been
lifting northeast across the area since this time yesterday is now
moving into Georgia. A few isolated showers have develop in the wake
of this low...generally moving southeast and east across the region.
These showers have developed in the greater instability this
afternoon...but deeper moisture has decreased as the low
departs...resulting only in the widely scattered coverages. With the
loss of daytime instability and with the slightly drier air in
place...expect this isolated convection to end shortly after sunset
(if not before). The upper low will weaken and lift rapidly to the
northeastern states by late Monday with a southeasterly middle level
flow developing over the area. This will allow a slow moisture
return in the middle levels...but lower level moisture remains slightly
lower than usual for this time of the year (with surface dewpoint
temperatures in the upper 60s most areas this afternoon through
tonight...and around 70 on monday). Any deep moisture and precipitation
chances (associated with the remnants of erika) will remain well
east of the forecast area through Monday. A light...mostly north to
northeast wind expected across the region tonight...continuing into
Monday. Winds will likely shift to east and southeast near shore
during the afternoon tomorrow as weak sea breeze circulation
develops. Low temperatures tonight again dropping into the upper 60s
over most of the interior with lower 70s down near the coast. High
temperatures on Monday climbing into the lower 90s over nearly all
of the forecast area...except for near the coast where the diurnal
onshore flow in the afternoon will limit temperatures to the
middle/upper 80s. 12/ds

Monday night through Tuesday night...a closed upper low swirls
around over the Texas/la border as the remnants of Erika move north
over the eastern Gulf of mex...to over the Florida Panhandle. Low level
flow over the northern Gulf Coast remains light on the synoptic
scale...allowing a daily winds coming onshore as a Gulf Breeze forms
and moves in...then shifts to offshore as the land cools and a land
breeze sets up. Guidance is inconsistent in handling any precipitation
formation...with the European model (ecmwf) the wettest and GFS the driest...with the
NAM in between. Have went with a blended solution as feel that a dry
slot over the north-central Gulf will see some moistening as the
remnants of Erika move north...but not as much as the European model (ecmwf) is
advertising....especially with the 00z ensembles advertising a more
dryer solution than the 12z European model (ecmwf). The result...have rain moving
back in Tuesday.

Long term [wednesday on]...Wednesday through Thursday...guidance is
advertising the remnants of Erika getting absorbed into the upper
low that has shifted from over Texas/Alabama eastward...to over MS/la. With
pieces of energy swirling around in this upper low...precipitation placement
will be a compromise between the GFS and wetter European model (ecmwf). The results is
scattered mainly daytime afternoon and evening thunderstorms and rain.

Thursday night through Friday...the GFS wanders the upper low
west-southwest...to over the northwestern Gulf...whilst the European model (ecmwf) opens it
while maintaining over the lower miss River Valley and southeastern
states. Even with this difference in the handling of the upper
dynamics...temperatures and probability of precipitation converge with the European model (ecmwf) and GFS...though
GFS does remain a bit warmer/drier. Still going with a blended
approach to the forecast...with probability of precipitation above seasonal and temperatures below.

Friday night through Sunday...the European model (ecmwf) continues to meander the
upper trough over the northern Gulf Coast through the coming
weekend...whilst the GFS meanders the upper low west...to off the
southern Texas coast. A surface ridge organizes over the eastern
Continental U.S....with the forecast area coming under an organized southeasterly flow.
Temperatures and probability of precipitation around seasonal continue.

Marine...a weakening ridge of high pressure will remain over
interior portions of the southeast U.S. Through the middle part of
next week...as a weak trough (remnants of erika) move north into the
eastern Gulf and basically dissipate through late week. This weak
pressure pattern will result in a general light to occasionally moderate
diurnal flow pattern...more southeasterly during the daylight hours
and more northeasterly at night. Seas 1 to 2 feet with generally
smooth conditions on protected waters through the week. Scattered
showers and storms over the marine area...primarily middle to late
week. 12/ds

&&

Preliminary point temps/pops...
Mobile 71 92 70 92 72 / 10 00 05 10 10
Pensacola 73 92 73 92 74 / 05 00 05 20 10
Destin 76 89 76 91 76 / 05 00 05 20 20
Evergreen 68 92 68 94 69 / 10 10 05 20 10
Waynesboro 68 92 69 94 70 / 10 05 05 10 10
Camden 67 91 69 93 70 / 10 05 05 10 05
Crestview 69 93 69 95 68 / 05 05 00 20 10

&&

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

$$

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