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fxus64 kmob 272027 

Area forecast discussion
National Weather Service Mobile Alabama
327 PM CDT Thu Apr 27 2017

Near term /now through Friday/...a front from last night's
passing system has stalled along i65, and is expected to wash out as
a surface ridge builds back west along the northern Gulf Coast
tonight. This building surface ridge in combination with a
developing surface low over the plains will provide moderate low
level winds and low level mixing to create light showers as Gulf
moisture moves back inland overnight into Friday. The southerly
flow will help to keep overnight temps well above seasonal levels
also, especially with an expected stratus deck expected to reform
tonight. Northwestern portions of the forecast area will see the
effects of the cooler air that had moved over them last night.
Lows in the low 60s northwest to low 70s close to the coast and
inland over southeastern portions of the forecast area.

Friday, shortwave energy digging south over The Rockies will help to
rebuild an upper ridge centered over the Caribbean. Increasing
subsidence will bring temps a few degrees above seasonal, ranging
from upper 80s north of Highway 84 to around 80 along the coast.

With the tidal range continuing to increase along with long period
swell continuing to move over area beaches from the south, have
extended the high risk of rip currents for another 24hrs. /16

Short term /Friday night through Sunday night/...Friday night,
with southerly flow in place and surface based moisture remaining
high, patchy late night fog is mentioned and looks to be more
focused over the eastern zones. Some of the fog could be locally
dense. Meanwhile. An amplification in the high level geo-
potential height field aloft begins to evolve Friday night with a
long wave trof digging over The Four Corners of the Desert
Southwest and downstream ridging noted, up across the southeast.
The passage of mid level impulses embedded in the flow aloft along
with a recovery in deep layer moisture and daytime instability
sets the stage for a chance of showers and storms on Saturday.

The main weather event and potential of severe storms, though,
looks to be approaching our area from the west on Sunday. Well
pronounced upper level storm system begins to eject eastward over
the plains Sunday, sending a corridor of deep layer lift,
coincident with anomalously high deep layer moisture,
strengthening wind profiles with height and instability, eastward
over the central Gulf Coast. The latest global spectral models
from 27.12z show a linear convective system moving across the
lower Mississippi River Delta Sunday afternoon. Thereafter, the
operational GFS is faster with the eastward progression of this
feature with the European model (ecmwf) slower. Due to these differences, will
consider a blended approach to the probability of storms which
increase from west to east through the course of the day Sunday,
with highest chances (categorical ranges) for much of the region
Sunday night. Due to 850 mb low level jet intensifying to 40 to 50
knots, 0-3 km bulk shear magnitudes approaching 50 knots and
hodographs that become strongly curved by late afternoon and
evening, there are concerns not only for damaging wind gusts but
also isolated tornadoes, especially in discrete storms that form
ahead of the main line. Within a belt of strong warm advection
processes forecasters note a narrow zone of precipitable water
values surging to ~2.35" moving east over the region. These
values are 3 Standard deviations above the climatological mean and
also a noteworthy mention is that this stands near the
climatological Max for the final day of April. With that said,
organized storms will likely be efficient heavy rain producers.
Latest storm total rainfall covering the Sunday to Sunday night
time-frame shows 2 to 4 inches focused along and west of I-65 for
now and this is where forecasters now Post a limited threat of
flooding. Warm days and mild to muggy nights continue.

Long term /Monday through Thursday/...following the passage of
the weather system by Monday, Monday night and Tuesday looks to
be rainfree. Unsettled weather pattern returns Wednesday and
Thursday. Daily highs on Monday in the mid to upper 70s a few
degrees below seasonal before lifting to more seasonable numbers
(lower 80s most areas north of the coast by the middle of next
week). Coolest night is Monday night, with overnight lows in the
lower to mid 50s over the interior.


Marine...a surface ridge stretching west over the northern Gulf
Coast will continue to create a moderate to strong onshore flow into
Sunday. Small Craft Advisory will most likely be needed beginning
later Friday night. A front will cross the area Sunday night,
bringing a moderate offshore flow temporarily to the area, but by
Tuesday, onshore flow returns. /16


Preliminary point temps/pops...
Mobile 69 84 73 86 / 30 30 10 30
Pensacola 72 82 74 83 / 30 30 10 30
Destin 72 80 75 82 / 20 20 10 20
Evergreen 70 86 70 91 / 30 30 10 20
Waynesboro 63 86 69 90 / 10 30 10 30
Camden 67 86 69 90 / 20 30 10 20
Crestview 72 85 69 90 / 30 30 10 20


Mob watches/warnings/advisories...
Alabama...high rip current risk through Saturday morning for alz265-266.

Florida...high rip current risk through Saturday morning for flz202-204-


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