Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Mobile Alabama
512 am CDT Thursday Aug 28 2014

Short term...(today and tonight)...surface high pressure centered to the
north and east of the forecast area shifts more to the east through
tonight. To the south...a weak inverted trough (or easterly wave) is
noted on surface maps as well as satellite imagery over far southeastern
Gulf moving ever so slowly toward the northwest. This feature is
prognosticated by models to continue to move slowly up toward the Gulf
Coast region by late tonight (and continue into and over the region
into the beginning of the middle/long term forecast period). Before this
feature arrives...will have another mostly rainfree day and night
across the local forecast area. Very similar to yesterday...mostly sunny
to partly cloudy across the entire forecast area today and then mostly
clear tonight...especially inland (but a few more clouds closer to
the coast as moisture/lift increase with the weak trough moving in
from the gulf). Will once again see isolated showers or storms late
this afternoon and early evening close to the coast in association
with the sea breeze circulation...and possibly extending a little
farther inland over western third of the forecast area where there is
slightly deeper moisture. Any convection lingering into the evening
will quickly dissipate early this evening...but maybe redevelop over
the coastal waters tonight as the trough approaches. High temperatures today
again slightly above normal for this time of the year...primarily in
the low to middle 90s. Low temperatures tonight near or a little below normal
over interior eastern zones...dropping to the middle 60s. Elsewhere
across the forecast area tonight...min temperatures ranging from the upper 60s
to lower 70s. 12/ds

Long term...[friday through sunday]...upper ridge over much of the
deep south mostly east of Texas is still prognosticated to weaken slowly
generally from west to east in response to a developing short wave
trough over the Central Plains. Earlier model runs showed this middle
level impulse digging over the MS River Valley late Friday into Sat
supporting better lift for showers and thunderstorms late Friday into
Sat but current trends now show less lift to the east because main
upper short wave to the northwest now looks to lift NE and dampen mostly
west of the MS river...or basically earlier than anticipated. This
pattern will still result in good coverage over much of our western
half of the County warning forecast area with less coverage generally east of the I-65
corridor, good coverage of showers and thunderstorms will also occur
over the adjacent Gulf waters affecting immediate coastal areas due
to a persistent surface trough stretching from the north central Gulf to
the Texas coast. With this have trimmed back on probability of precipitation for Friday into Sat
with slightly less coverage to the east. As the better moisture in
the low levels continues to advect north late in the week and over
the weekend expect mostly cloudy conditions Friday through sun. The
main concern with the stronger thunderstorms during this period will
be gusty winds mostly in the 30 to 40 miles per hour range...frequent cloud to
ground lightning and periods of very heavy rain. As for temperatures will
lean towards a blend of the mav and European model (ecmwf) tweaking these values down
a few degrees mostly for consistency with surrounding weather forecast offices. Highs
will be mostly in the lower 90s over the northern half and the upper
80s to near 90 further south both Friday and Sat. Lows will be in the
middle 70s Friday and Sat night.

[Sunday through wednesday]...surface to 500 mb ridge of high pressure will
rebuild slowly through middle week. This patter will continue to lead
to a good onshore flow and better moisture advection through midweek
through with limited forcing in the middle to upper levels showers and
thunderstorms should remain mostly scattered through the extended
periods generated mostly from daytime heating and weak afternoon
seabreeze circulations. As for temperatures will continue use a blend of the
current mav and European model (ecmwf) MOS guidance through the period. Highs will
continue to remain mostly in the lower 90s well inland and the upper
80s to near 90 further south to the coast. Lows will be mostly in the
lower to middle 70s through the period. 32/ee


Aviation...(28/12z issuance)...mainly a VFR forecast through next 24
hours. Will carry thunderstorms in the vicinity late afternoon near the coastal terminals
(mob...bfm...pns) but coverage of showers and storms will be very
isolated. Otherwise a predominant light southeasterly surface wind flow
expected. 12/ds


Marine...high pressure ridge to the north of the marine area over
the southern states will weaken through Friday as a inverted trough
(easterly wave) moves north across the eastern Gulf of Mexico. The
trough moves inland and dissipates over the weekend. Otherwise...a
high pressure ridge will build over the southeastern states and the
eastern Gulf. With this a general light to occasionally moderate
southeasterly wind is expected to prevail through the period. Seas
initially up to near 4 feet...but decreasing to around 2 feet by the
middle and end of the forecast period. 12/ds


Fire concerns.


Preliminary point temps/pops...
Mobile 91 73 91 76 88 / 20 05 40 40 60
Pensacola 92 74 91 79 88 / 20 05 40 40 60
Destin 91 77 90 79 87 / 20 05 50 40 60
Evergreen 93 65 94 73 90 / 05 05 20 30 60
Waynesboro 93 68 93 74 89 / 10 05 20 30 60
Camden 94 66 95 74 92 / 05 05 20 30 60
Crestview 94 67 92 73 90 / 05 05 40 30 60


Mob watches/warnings/advisories...


National Weather Service Glossary of Abbreviations