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Area forecast discussion 
National Weather Service Mobile Alabama
415 am CDT Friday Sep 4 2015

Short term [today and tonight] upper trough develops over the
eastern Seaboard...stretching a bit inland over the Carolinas/GA. An
upper high develops over the northeastern states...with a surface
ridge developing along the East Coast...from New England south to
over the Carolinas. This creates a more organized northeasterly flow
over the southeastern states...and the forecast Saturday morning. With a
light and variable flow over the forecast area and surrounding areas...a soupy
airmass remains...with precipitation h20 values generally 1.8" and above.
The wild card is a band of significantly lower precipitation h20 values
(generally around 1.4-1.5") stretching across the southern-most
MS/al/FL counties of the forecast area.

With the high precipitation h20 values...have went higher than the GFS with
respect to probability of precipitation today...more inline with the NAM...though not quite
as wet as the European model (ecmwf). Feel that with the dry band along the
coast...initial formation of thunderstorms and rain with the Gulf Breeze moving inland
will be a bit limited...but as the activity works inland...greater
coverage will result. With a drier airmass bordering the northern
regions of the forecast area...feel any development north of Highway 84 will
see a higher chance of damaging downbursts...with a decent dry layer
centered around 500mb. Temperatures...have went a bit above seasonal
today...with an upper ridge stretching north over the eastern plains
the reason.

Tonight...have went with a diurnally driven...evening land thunderstorms and rain
washing out...then re-developing offshore as a land breeze sets up.
Any areas that see decent rain today into this evening will see fog
development have put fog into the forecast. Temperatures
around seasonal continue,

There is a high risk of damaging downbursts across the area today
into tonight...with highest across northern parts of the area. /16

Long term [saturday through friday] upper trough will amplify
across the eastern states into the southeast over the weekend. An
upper low is expected to cutoff in the base of the trough over the
southeast states and slowly retrograde westward through much of the
work week. This will keep unsettled conditions in the forecast with
scattered showers and thunderstorms each day. Showers and
thudnerstorms will be most numerous in the afternoon and early
evening hours...however west/ the upper low isolated
shower or storm cannot be ruled out during the overnight hours. The
increased cloudiness and precipitation will keep high temperatures near or
slightly below normal through much of next week. Global models
indicate rain chances increasing late in the week as a cold front
approaches the area from the north. /13


12z issuance...general VFR conditions expected though
the forecast. Some local drops in visbys to MVFR levels after
midnight possible...but am not expecting widespread development./16


Marine...light and variable flow currently over the marine portions
of the forecast area will become a more organized northeasterly tonight into
Saturday as a surface ridge develops along the East Coast. This
general northeasterly flow will last through the weekend into the
coming week...then become more diurnally driven middle week as a
surface trough develops over the northern Gulf Coast. /16


Preliminary point temps/pops...
Mobile 92 73 93 74 90 / 20 20 40 30 40
Pensacola 90 75 90 75 87 / 20 20 40 40 40
Destin 86 76 88 76 86 / 20 20 40 40 40
Evergreen 94 71 94 71 90 / 20 20 40 30 40
Waynesboro 95 71 94 72 92 / 20 20 30 20 30
Camden 94 72 95 72 90 / 20 20 30 20 30
Crestview 93 71 92 72 88 / 20 20 40 40 40


Mob watches/warnings/advisories...


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