Scientific Forecaster Discussion
Area forecast discussion...updated
National Weather Service Mobile Alabama
1154 PM CDT Friday Aug 22 2014
Aviation (06z issuance)...predominate VFR conditions are expected
through the next 24 hours. Only a small chance of a very isolated
storm Saturday afternoon and will leave the mention of thunder out of
the terminal forecasts. 34/jfb
Previous discussion... /issued 307 PM CDT Friday Aug 22 2014/
Dangerous heat indices forecast to continue into the weekend...
Short term [tonight through Saturday night]...hot...humid conditions to
continue as the upper level ridge umbrellas the region. Dangerous
heat index values reaching 106 to 110 degrees will continue through
late afternoon and return late Saturday morning through early
Saturday evening. Spotty thunderstorms should dissipate early this
evening and fire up again tomorrow afternoon as minor waves rotating
around the upper level high manage to release some of the
instability overlying the region. /08 jvw
Deep layer ridge of high pressure holds strong Saturday night with
any isolated storms from Saturday afternoon...dissipating quickly after
sunset. Little change in overnight low temperatures...ranging from
74 to 79...the upper end of this range being closest to the coast.
Long term [sunday through friday]...the large upper level ridge of
high pressure will continue to expand across the Mississippi and
Tennessee Valley region and through much of the deep south again
Sunday. An inverted surface trough will stretch across the Florida
Panhandle into southwest Alabama and southeast Mississippi. Hot and
humid conditions will persist with these features...with temperatures
again ranging from the middle 90s to near 100. Heat indices may again
range from 105-110 across much of the region...and later shifts will
need to monitor for potential extension of the heat advisory across
portions of the area Sunday. Isolated showers and thunderstorms are
again possible Sunday...potentially more scattered in coverage across
eastern portions of the County warning forecast area where precipitable water (pwat) values
increase to 1.8 to 2 inches by Sunday afternoon. The upper level
ridge will slowly pivot westward by Monday...still extending across
much of the the Mississippi and Tennessee Valley regions. Medium
range solutions are still in agreement with bringing an area of
deeper moisture southwestward into our forecast area on the
southeastern and southern periphery of the ridge axis by Monday
afternoon. With precipitable waters potentially increasing to over 2.25 inches...at
least scattered showers and thunderstorms look to be a good bet
across the region... and will maintain thunderstorm probabilities in
the 30-50 percent range across the County warning forecast area Monday. Upper ridging may
build back eastward through the deep south Tuesday into Wednesday
before breaking down late in the week as westerly flow increases
ahead of the next trough advancing east across the central Continental U.S..
thunderstorm probabilities trend downward Tuesday and Wednesday as
the deeper moisture looks to move to the west of the region and as
upper ridging builds back in. A gradual increasing trend in
probabilities offered to close out the week...the better chances
looking to return on Friday...as Gulf moisture opens up ahead of
upper trough moving out of the plains.
Temperature-wise...the increased chance of rain should knock highs
down closer to normal Monday. Readings then look to average near to
slightly above normal through the remainder of the extended forecast
period. /21 /10
Marine...generally a light to occasionally moderate wind flow regime
will persist across the northern Gulf through the weekend as a strong
high pressure system remains centered over the region. Surface winds
will begin increasing and waves building by the beginning of the work
week as a frontal system pushes into the area from the northeast. /08
Alabama...heat advisory from 11 am Saturday to 7 PM Saturday for the
following zones: Butler...Choctaw...Clarke...Conecuh...
Mobile...Monroe...upper Baldwin...upper Mobile...
Florida...heat advisory from 11 am Saturday to 7 PM Saturday for the
following zones: coastal Escambia...coastal Okaloosa...
coastal Santa Rosa...inland Escambia...inland Okaloosa...
inland Santa Rosa...
MS...heat advisory from 11 am Saturday to 7 PM Saturday for the
following zones: George...Greene...Perry...stone...Wayne...