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Area forecast discussion 
National Weather Service Mobile Alabama
445 am CDT Friday may 22 2015

Short term [today through Saturday night]...little chance of rain
inland. Weak zonal flow at 500 mb will host small perturbations along
a front which has already passed US to the southeast. Scattered
showers and thunderstorms will form along it generally offshore
through this afternoon. Cape rapidly drops below 400 j/kg north of 60
miles offshore. Precipitable water drops below an inch north of a
line from Hinton to Luverne Alabama....and Li is +3 offshore
increasing to +12 going inland within 50 miles of the coast. On top
of that...Post frontal layer subsidence and weak well
as low dewpoints will keep convection none today and tonight over

Highs today in the upper 70s in the far northern zones and low 80s
further toward the coast. Lows in the far northern zones in the
upper 50s and low 70s further toward the coast. /77

This afternoon's wet microburst risk is low

Upper level storm system over The Four Corners of the Desert
Southwest Saturday is forecast to gradually lift northeast up across
The Rockies Saturday night. This causes downstream Gulf middle level
ridge to undergo amplification during the day. With the
strengthening middle level ridge aloft...rain chances look to be minimal
Saturday. Well defined surface high pressure is to be aligned from
the central Appalachians to off into the western Atlantic. Resultant
wind flow turns more southeasterly with high temperatures on Saturday
into the upper half of the 80s. There is a moderate
risk of rip currents along the Gulf beaches of Alabama and northwest
Florida for Saturday due to an increase in onshore flow. For
Saturday night...boundary layer moisture trends higher through the
night as a low level 1000-850 mb Theta-E ridge axis becomes oriented
from the eastern Gulf...northwestward into Oklahoma. The better
moisture bisects the forecast area in half with the higher end along
and west of a line from Waynesboro Mississippi to Destin
Florida...and the drier air east of this line. Weak low layer lift
within the better moisture may result in a slight chance of late
night showers/storms from portions of interior southeast Mississippi
to the Gulf Coast and points offshore. A muggy night is expected with
lows in the middle 60s interior to the lower half of the 70s coast. /10

Long term [sunday through thursday]...the global weather models
show an eastward progression in the geopotential height fields aloft
with a well defined...amplified middle level ridge setting up from the
middle Atlantic...southward to over Florida to begin the outlook. The
local area sees a potentially active southwest flow aloft between the
ridge to the east and trough axis over the plains for much of the
period. A series of middle level impulses/ascent within the high level
southwest flow operates on deepening layer moisture as trough axis to
the west taps Gulf moisture and pulls it northward over the
Mississippi Valley. This brings the potential for a chance of
showers/storms for the latter half of the Memorial Day Holiday
weekend. With little overall change in the synoptic scale weather
pattern Tuesday through Thursday...chances of showers/storms remain
in the forecast. Some of the storms could be strong at times
producing brief strong wind gusts...frequent lightning and locally
heavy rains. Although the risk of widespread severe storms is low
during the medium isolated occurrence cannot be ruled out
mainly during the daytime hours when better instability is realized.

With high pressure to the east...a breezy southeast to southerly flow
is possible mainly along the coast each day. Forecasters are
evaluating the Prospect of a high risk of rip currents Sunday...which
may continue into Memorial Day.

Daytime highs are forecast to range from 85 to 90 over the interior.
Over the beaches...closer proximity to Gulf keeps highs in the lower
half of the 80s. With surface high pressure firmly established from
the western Atlantic into the eastern US...overnight lows moderate
back into the Lower/Middle 70s for next week. /10


22.12z issuance...VFR conditions will prevail through the next 24
hours. Wind light to moderate around 5 knots from the northeast
veering to east Saturday and southeast Sunday. /77


Marine...a high will dominate the north central Gulf behind a cold
front pushing out over the northern Gulf today. The front will bring
scattered showers and thunderstorms along it well offshore and
moderate to strong northwest winds behind it. The wind will quickly
decrease and veer northeast then become southeast by Saturday. As
the high moves further east this weekend...the wind will strengthen
to 15 to 20 knots over the Gulf and seas will increase...approaching
6 feet offshore. The Swan came out slightly higher than the gww wave
model but we kept the output because it agreed more closely with the
bretschneider. /77


Preliminary point temps/pops...
Mobile 83 62 87 71 87 / 10 05 10 20 40
Pensacola 83 66 86 73 86 / 10 10 10 20 40
Destin 84 68 86 74 84 / 10 10 05 20 30
Evergreen 80 59 88 67 89 / 05 10 05 10 20
Waynesboro 80 58 88 67 87 / 05 05 05 10 40
Camden 79 58 88 66 87 / 00 10 05 10 20
Crestview 85 64 89 67 90 / 05 10 05 10 30


Mob watches/warnings/advisories...


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