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Area forecast discussion 
National Weather Service Mobile Alabama
614 PM CST Thursday Nov 26 2015

Discussion...updated for latest aviation discussion below.


00z issuance...VFR to start off this forecast period with scattered
to occasionally broken high clouds passing overhead. Moist
southeasterly low level flow will support development of MVFR ceilings
late tonight and early Friday morning before a return to VFR looks
probable late Friday morning into Friday afternoon. Light east/NE winds
continue tonight into Friday morning...before becoming more easterly
around 10 knots during the day Friday. /21


Previous discussion... /issued 323 PM CST Thursday Nov 26 2015/

Near term /now through Friday/ upper ridge persists over the
southeast states through Friday while a strong surface ridge remains
in place over the area through tonight...then weakens somewhat on
Friday. East to southeast winds currently over the area...breezy
near the coast...become easterly tonight then begin to subside on
Friday afternoon. The breezy coastal winds along with a large tidal
cycle will maintain a high risk of rip currents along area beaches
through Friday. Dry conditions continue over the area through
Friday. Lows tonight will range from the lower 50s inland to the
upper 50s near the coast and highs on Friday will be in the lower to
middle 70s. /29

Short term /Friday night through Sunday night/ upper low off
the Florida coast slowly sags south as another meanders around over the
western Continental U.S.. with the one off the Florida coast slowly sagging upper ridge stretching northeast from an upper high over
mex over the southeastern states (and the fa) slowly rotates
clockwise...eventually stretches west over the Gulf of mex and the
Caribbean. This allows the upper level flow to shift to a general
west-east over the southern half of the Continental U.S. By Monday morning...and with
that...allow a stream of impulses being ejected from the western
upper low to pass increasingly closer to the lower miss River Valley
and southeastern states. This rotates a surface front running from Texas
to the Great Lakes southeastward and disrupts the moderate to strong
easterly low level flow around the base of a surface ridge stretching
SW along the Appalachians.

For the forecast...with disrupting of the low level flow...the
problem with high rip currents and rough surf will ease Friday into
Saturday. Moisture levels remain high (at or above seasonal levels)
enough that even with any subsidence from the upper ridge shifting
south over the Gulf...temperatures remain unseasonably warm into Monday. 5
- 10 degrees above seasonal for both overnight and daytime temperatures in
this case. As the surface front sags towards the forecast area...rain showers look to
make an appearance to the northwest of the forecast area late Saturday night and
begin to shift very slowly southeast across the northwestern
portions of the forecast area into Sunday night. These showers do not look to
provide any significant cooling to drop temperatures closer to seasonal
quite yet.


Long term /Monday through Thursday/...the western upper low begins
to head east...getting a slight northward deflection from the still
present upper ridge over the Gulf/Caribbean. As impulses eject and
stream east ahead of the system...they slowly push the weak surface
front across the forecast area Monday into Tuesday...then more quickly Tuesday
night into Wednesday night time frame. Do not see sufficient
instability for any thunderstorms and rain any time during its have went
with basic rain in the forecast. As the front sags south across the
forecast area...the increased cloud cover and rain will cool temperatures to
around...then a bit below seasonal Tuesday night on (5 degrees below
for Thursday/Thursday night). Until then...highs in the 70s with
overnight lows in the 50s to low 60s expected Monday through Tuesday.


Marine...a strong ridge of high pressure over the southeast states
gradually weakens through Monday while a cold front approaches from
the west. Moderate to strong easterly winds over the area subside
to a light to moderate flow by Saturday. A light southeasterly flow
develops on Monday then switches to an increasing northerly flow
Tuesday night as the cold front moves through. A Small Craft
Advisory remains in effect for much of the marine area through
Friday morning...then will be in effect just for the 20-60 nm
portion Friday afternoon before ending as seas subside. /29


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

Florida...high rip current risk through Friday afternoon for flz202-204-

GM...Small Craft Advisory until noon CST Friday for gmz631-632-650-

Small Craft Advisory until 6 PM CST Friday for gmz670-675.



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