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Area forecast discussion...updated 
National Weather Service Mobile Alabama
723 PM CDT Wednesday Jul 29 2015

Mesoscale update...latest satellite and radar trends show latest
round of deep convection moving through region at the moment. In the
past hour there has been a trend towards decreasing coverage. Expect
this trend to continue for a while but then sometime during the late
evening...scattered showers and isolated thunderstorms should re-
develop in response to an approaching upper S/wave and associated
lower tropospheric pressure trough. Latest global models...NAM and
hrrr suggest an area of precipitation will develop and move southwestward into our
area. Do not expect it to amount to much...but more importantly...those
outflows will endure into the early morning hours and will serve to
enhance coverage early tomorrow...especially along south of I-65. We
are currently advertising a 60% chance of rain for tomorrow. Put
minor tweaks on overnight winds...pops...qpf...clouds and weather
grids. Heat advisory expired at 7 PM CDT. New package out shortly.
/23 jmm


Aviation...30/00z taf issuance...scattered showers and storms
weakening and becoming less widespread as we begin to lose daytime
heating. Believe some eak convective activity will continue well
into the evening hours upper level shortwave continues
to drop south across the region and low level surface trough axis
(boundary) is in place over the area. Ceilings and surface visibility
will be at VFR criteria for nearly all locations tonight...but there
will likely be some broken middle/high levels clouds and perhaps some
patchy light fog at some locations. Surface winds are expected to be
light west to southwest overnight. Another round of more widespread
showers and storms across the region on Wednesday...with
periods of IFR ceilings and visibilty. 12/ds


Previous discussion... /issued 334 PM CDT Wednesday Jul 29 2015/

Near term...(tonight and tomorrow)....the synoptic pattern changes
very little through tomorrow afternoon. Essentially the southern deeply-
reflected ridge remains intact as impulses rotate around it in the
middle- and upper flow. Main thing is determining evolution of left-
over showers and thunderstorms (some that will produce severe
thunderstorm wind gusts on an isolated basis through middle evening).
Looks like the west-East Line entering our County warning forecast area will be the main weather
for the rest of this afternoon and evening (as the first push moves
southward into the coastal waters). A nice zone of MLCAPES 2000-2500 j/kg
will be present as the storms move further southward (and this will average being
the highest zone of instability as we move into the early evening
hours). Also will be watching another area of deep convection up over
northern/central Alabama that is poised to move S in the flow. A well- defined
piece of upper level momentum supporting this feature via
consensus...but the recovery of instability is in question. May just
end up being a decaying area of showers and storms that moves in and
through during the 9 PM-2 am time frame. Another muggy night in store
with lows in the middle and upper lower 80s along the beaches.
Expect elevated shower and thunderstorm coverages once again tomorrow
as low level boundary continues moving southeastward into our area. Highs in
the low to middle 90s. We should be just out of heat advisory criteria
tomorrow afternoon. So...the heat advisory will be allowed to expire
at 7 PM this evening and will not be re-issued. /23 jmm

Short term...(tomorrow evening through Saturday evening)...the
pattern changes very little overall from what was described above. A
low level boundary does settle into the area from the north and
there is enough moisture...instability and lift to support showers
and thunderstorms each day through the period. Highs will be a little
cooler given the associated additional clouds brought the via the
boundary. There will be a northwest-southeast oriented moisture gradient...and on
average...rain chances will be higher southeast of I-65 each day. Highs
generally 90 to 95 deg(f) with overnight lows in the middle and upper
70s to around 80 along the beaches. /23 jmm

Long term...(sunday through next wednesday)...aloft...the familiar
northwest flow pattern persists however there are some changes in the
atmospheric low levels. Beginning Monday...the westward extension of the
low-level Bermuda high builds westward and we benefit from the
increasingly more southerly return flow that will bring about a moderating
trend of the northwest-southeast moisture gradient. This setup keeps US susceptible
to middle- and upper S/waves that will move south in the low but will keep
the low level moisture content high. So...we are looking at a
continued unstable weather pattern in the extended. Highs in the low-
middle 90s each day with overnight lows in the middle and upper
70s...except around 80 along the beaches. /23 jmm

Marine...the overall pattern changes very little over the next week.
Offshore flow will be replaced by a more variable continued light flow
on Saturday as a pressure trough settles over the Gulf of Mexico. There
will be a tendency for the wind flow to become more southerly in the
Monday through Wednesday time frame as high pressure tries to build
once again in the eastern Gulf of Mexico. The main marine hazard will
be storms that form daily and move from land to the water during the
afternoons. The associated gusty outflows will bring sudden
squalls...frequent cloud to surface lightning and possibly
waterspouts. Looking at the entire forecast period...precipitation
coverage over the coastal waters will be the greatest over the next
two days. /23 jmm


Preliminary point temps/pops...
Mobile 96 76 93 77 91 / 60 60 60 60 50
Pensacola 96 78 91 78 89 / 60 60 60 60 40
Destin 93 79 89 80 88 / 50 60 60 60 50
Evergreen 96 75 95 75 92 / 60 60 60 40 40
Waynesboro 97 75 97 75 93 / 40 50 60 40 40
Camden 95 75 96 76 92 / 50 50 60 40 30
Crestview 97 76 93 76 91 / 60 60 60 40 30


Mob watches/warnings/advisories...


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