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Area forecast discussion 
National Weather Service Mobile Alabama
323 PM CDT Tuesday Mar 31 2015

Short term (tonight through Thursday night)...showers and
thunderstorms developing mainly over central and northern parts of
Alabama will possibly affect areas along and north of a line stretching
from Butler to Andalusia in Alabama later this afternoon continuing
through Wednesday. This convection is forming mostly along and north of a
stalled frontal boundary situated over the central part of the state
which drifts further south through Wednesday afternoon. As a result
slightly better coverage of precipitation can be expected mainly over
northern sections of the County warning forecast area mostly during the daylight hours on
Wednesday. With steep lapse in the middle levels combined with wet bulb zero
values mostly below 9.5kft the threat for a few strong to severe
thunderstorms will continue through Wednesday afternoon...with gusty
straight line winds and large hail being the main threats. Latest WV
loops also show the next short wave moving southeast over the middle section of
the country... prognosticated to move across central and northern parts of
MS and Alabama late Wednesday into Thursday...resulting in better lift or middle level
forcing in advanced of this system through Wednesday afternoon. Further
south over lower parts of the County warning forecast area skies will be mostly cloudy with
gusty southwest winds mostly during the afternoon hours when surface
temperatures are the warmest. As for temperatures will continue to lean towards the
warmer mav guidance through Wednesday and adjust for consistency with
surrouinding weather forecast offices. Lows tonight will fall to upeer 50s to lower 60s
for most inland areas and the middle 60s close to the coast. Highs on
Wednesday will climb to the lower to middle 80s for most inland areas and
the upper 70s along the immediate coast. 32/ee

A weak shortwave embedded in the semi-zonal flow aloft will move
east of the region on Thursday. Despite low level southerly
flow...forecast soundings show a significant amount of low to middle
level dry air present. Therefore...rain chances overall will be
low...with just a slight chance over well inland locations. The dry
weather will continue into Thursday night. Temperatures will remain above
normal with highs in upper 70s to lower 80s and lows in the upper 50s
to lower 60s. 34/jfb

Long term (friday through tuesday)...a stronger shortwave over the
intermountain west Thursday night will quickly move east into the
Midwest/Tennessee Valley by Friday night. This feature will send a stronger
cold front southeast toward the area. There are still timing
differences in the guidance with the European model (ecmwf) on the slower side of the
solutions. The sref mean is a little faster...bringing a chance for
showers and thunderstorms ahead of the front over the northwest zones by
Friday afternoon...with rain chances increasing further in the
evening. This forecast will follow the sref ensemble mean. The band
of showers and thunderstorms will likely weaken late Friday night as
they move closer to the coast as the aforementioned shortwave stays
well north of the region. The front is forecast to move offshore
early Saturday morning. Besides a slight chance of showers along
coastal areas early in the morning...the majority of Saturday is
looking dry and cooler. Highs are forecast to be in the middle 60s to
around 70...which is a few degrees below normal. Below normal temperatures
will carry into Saturday night as the center of Canadian high
pressure moves over the interior southeast. Lows in the 40s are
expected over most of the area...slightly warmer along the immediate
coast.

The high quickly moves east on Sunday into early next week with an
onshore flow becoming reestablished by Sunday night into Monday.
There is only a very small chance of an isolated shower over southeast MS on
Sunday with most of the area staying rain free as the middle levels
remain dry. Rain chances increases slightly as we head into early
next week as deep layer moisture increases along with the development
of weak to moderate warm air advection. The overall upper level
pattern will feature semi-zonal flow Monday with ridging beginning to
build in earnest by Tuesday. Any significant increase in rain chances
will hinge on fast moving shortwaves embedded in the flow which are
very difficult to pinpoint this far out. Temperatures during this
period will climb back to above normal levels. 34/jfb

&&

Aviation...
31.18z issuance...VFR to MVFR ceilings through 01.06z followed by IFR to
LIFR ceilings and visibilities through 01.13z then improving to MVFR to
VFR ceilings through 01.18z. A stalled frontal boundary mostly over
central sections of Alabama and MS will continue to be the main focus for
showers and thunderstorms to develop...later this afternoon
continuing into the morning hours on Wednesday. Winds will continue from
the southwest at 12 to 16 knots with gusts to 20 knots though early
this evening shifting west diminishing to 4 to 6 knots overnight and
early Wednesday then becoming southwest increasing to 12 to 16 knots by
late morning and early afternoon. Higher wind gust will be likely
later in the day on Wednesday. 32/ee

&&

Marine...high pressure will continue over the eastern and north
central Gulf through Wednesday then slowly weaken from west to east
later in the week in response to a cold front approaching from the
northwest. Southerly winds and seas will build ahead of the front
late in the week followed by a moderate to strong offshore flow in
the wake of the front late Friday through Saturday morning. A
moderate to strong easterly flow is expected by late Sunday into
early next week as a strong surface ridge of high pressure builds
along the Carolina coast. Higher winds and waves will continue
during the afternoon and evening hours with the onshore flow through
Friday due to afternoon heating and seabreeze circulations. 32/ee

&&

Fire weather...afternoon dispersions will be fair to generally good
on Wednesday with generally good to good dispersions on Thursday.
Dispersion values could reach 75 to 80 Thursday afternoon across
portions of southwest Alabama and inland southeast Mississippi.
34/jfb

&&

Preliminary point temps/pops...
Mobile 61 82 61 81 62 / 10 10 10 10 05
Pensacola 64 80 61 80 63 / 10 10 10 10 05
Destin 67 77 63 75 65 / 10 20 10 10 05
Evergreen 60 84 56 83 57 / 20 30 20 10 05
Waynesboro 59 82 60 83 63 / 10 20 20 20 10
Camden 60 83 57 83 59 / 30 40 20 20 05
Crestview 60 83 55 83 54 / 10 20 10 10 05

&&

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

$$

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