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Area forecast discussion 
National Weather Service Mobile Alabama
401 PM CDT Thursday Aug 21 2014

..elevated to high afternoon heat index values forecast over the
weekend may lead to an increased occurrence of heat related
illness....

Short term [tonight through Friday night]...ridging (sfc and aloft) over the
area will continue to maintain the dry...and hot...pattern in the
short term. Isolated storms have developed this afternoon across the
region and these will persist until shortly after dark. Current
dewpoint temperatures are in the lower 70s for most locations across
the forecast area...except for upper 70s along the immediate coastal
areas. With actual air temperatures in the low to middle 90s across most of
the area...current heat indices (hi) are in the 102-107 degree
range. A few locations seeing hi's around 108 or just above. Dewpoint
temperatures will remain relatively unchanged tonight...and min temperatures
are expected to be in the low 70s inland and middle 70s coastal. For
Friday...very similar conditions as today but perhaps even a little
hotter over the interior. Overall maximum temperatures tomorrow expected to be
in the middle to upper 90s inland and lower 90s coastal. Heat indices
are again expected to be within the 104-108 degree range (with some
isolated locations above 108 degrees). Heat advisory criteria for our
area is 108 to 112 degrees...and while there may be some isolated
values in the lower end of that range...overall maximum hi's are expected
to be just below criteria. We did issue another Special Weather
Statement referencing the heat and will monitor trends. More isolated
showers and storms tomorrow...mainly late afternoon and evening and
primarily closer to the coast. 12/ds

Deep layer ridge of high pressure controls the local weather pattern
through Friday night. Generally a temperature forecast with
overnight lows on the muggy side...lower/mid 70s interior...closer
to 80 at the beaches. Light wind pattern with surface high
positioned over the Gulf. /10

Long term [saturday through thursday]...upper level high pressure
will remain centered in the vicinity of the lower and middle
Mississippi Valley region this weekend...with the ridge axis
expanding across most of the deep south. This feature will continue
to bring heat impacts to our forecast area this weekend...with highs
ranging from the middle 90s to around 100 across the region both
Saturday and Sunday. Continued humid conditions will result in heat
indices ranging between 104 and 108 degrees...with isolated
locations reaching around 110 both afternoons. A heat advisory may be
necessary into the weekend across portions of the County warning forecast area. Any
thunderstorm activity looks to remain isolated and focused mainly
near the seabreeze Saturday afternoon. Short range solutions are
still in agreement with bringing an area of deeper moisture
southwestward around the ridge into much of Georgia and westward
into portions of south central Alabama and the northwest Florida
Panhandle by Sunday afternoon. Precipitable water values increasing
to around 2 inches may bring a slightly better chance of showers and
thunderstorms to eastern portions of our forecast area Sunday.

The upper level ridge axis is prognosticated to shift slightly northward and
extend roughly from eastern Texas/Oklahoma and across the middle
Mississippi River valley and into the Ohio Valley region early next
week. Our forecast area will become placed on the southeastern fringe
of the ridge axis Monday and Tuesday. A slug of deep layer moisture
will remain in place across much of our area Monday...with precipitable waters as
high as 2.2-2.3 inches...which will be favorable for at least
scattered showers and thunderstorms across the region. Probability of precipitation were
trended upward a bit from the previous forecast. Temperatures should
trend a few degrees cooler early next week given the increased
moisture and northward advancement of the ridge axis. A northeast to
east flow pattern aloft should prevail Tuesday into Wednesday as the
upper ridge remains oriented from Texas through the Tennessee/Ohio
Valley regions. Isolated to scattered convection will be possible
into midweek...though medium range solutions differ on the amount of
deep layer moisture that will be available.

Daytime highs next week in the lower half of the 90s. For low
temperatures...little change here with 72 to 75 interior to 78 to 81
along the coast/beaches. /10/21

&&

Aviation (21/18z & 22/00z issuances)...primarily a VFR forecast through
next 24 hours. Thunderstorms in the vicinity through the late afternoon hours near the
coast...but very isolated at best. Any lingering isolated shower or
storms dissipate shortly after sunset over land areas...but develop
over the offshore marine area late tonight (should stay south of the
terminals). Light onshore surface wind flow during the afternoon and
early evening...light offshore during the late night and early
morning hours. 12/ds

&&

Marine...strong high pressure will persist over the north central
Gulf through the early part of the weekend...then gradually weaken
late in the weekend and into the early part of next week. A
predominant light to moderate west to northwest wind flow will
continue over the marine area through the weekend...becoming east to
southeast then gradually build beginning by next week as the high
pressure over the Gulf weakens and a stronger ridge builds just
inland from the Atlantic Seaboard. Little change in seas expected.
12/ds

&&

Preliminary point temps/pops...
Mobile 75 97 75 97 75 / 10 20 10 20 10
Pensacola 78 97 79 98 79 / 10 20 10 20 10
Destin 79 91 80 93 80 / 10 20 10 20 10
Evergreen 72 99 72 99 72 / 10 10 10 10 10
Waynesboro 73 99 73 99 73 / 10 20 10 10 10
Camden 72 99 73 98 73 / 10 10 10 10 10
Crestview 71 99 73 100 73 / 10 20 10 20 10

&&

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

$$

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