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Area forecast discussion...updated 
National Weather Service Mobile Alabama
644 am CDT Sat Sep 20 2014

Update...just sent a quick update to increase cloud cover in the
eastern zones this morning. Low stratus has been rapidly spreading
westward and expect this trend to continue for the next few hours.
Once diurnal heating commences in earnest middle to late morning...the
stratus will begin to gradually erode. Mostly sunny skies are still
expected for all areas by this afternoon. 34/jfb

&&

Aviation update...baed on satellite trends added a tempo group of
IFR ceilings at pns through middle morning. The low ceilings are not expected to
reach bfm/mob at this time but will monitor satellite trends
through the morning. 34/jfb

&&

Previous discussion... /issued 428 am CDT Sat Sep 20 2014/

Short term (today and tonight)...the deep layer atmosphere will be
very dry today due to north-northwest middle to upper level winds on the backside
of a shortwave trough to our east. This is in combination with surface
high pressure ridging into the region from the northeast.
Precipitable water will drop to around 1.25 inches or less...
resulting in a rain free day across the region. Highs will climb into
the middle to upper 80s...which is very close to normal for this time of
year. It will also feel a little less humid as dewpoints mix out into
the 60s. There is still enough low level moisture present early this
morning to produce some low stratus over southern Georgia into
southeast Alabama. Expect some of this stratus to move into portions
of south central Alabama and the interior Florida Panhandle early
this morning. The stratus will mix out by middle to late morning with
mostly sunny skies prevailing the rest of the day.

Dry weather continues into tonight with lows dropping into the low
to middle 60s over inland areas with upper 60s to around 70 across the
I-10 corridor. 34/jfb

(sunday through monday)...little chance of rain through early Monday
with dry north to northwest flow starting somewhat light but
increasing slightly through Monday night. There is a ridge at the
surface nosing into our area from an anticyclone southeast of
Newfoundland...over Bermuda...and into the Georgia coast westward
into the Gulf Coast region and lower Mississippi Valley. This will
break in two leaving US under the influence of a surface high over
the plains moving southeast Sunday. Ahead of it will be a cold front
that will bring a chill to our northern counties Tuesday morning. Now
that front will move toward US Sunday reaching the northern part of
our region area by late Sunday night. Precipitable water stays around
or slightly above one inch across our area through Sunday night.
Lifted index will be around +1.5 so it will be stable with minimal
prospects for convective rain until around noon Monday. At that
point...ahead of the front as it sweeps through...precipitable water
will rise slightly but not get much above 1.5 inches and lifted index
will drop until it gets to around -1 which is generally in the
scattered thunder category. For that reason we went for only 30
percent or less in a band moving south...and we are not expecting any
spectacular rain out of this at the moment. 77/blowing dust

Long term (monday night through friday)...where we left off was
talking about non-spectacular rainfall Monday...but what some may
consider spectacular is the cool air behind the front moving
through. Lows Tuesday morning will reach into the middle and upper 50s
north of a line traversing our area from east to west along and
beyond U.S. Highway 84. Temperatures will rebound to more normal
figures through the rest of the week.

A dry north 500 mb flow will persist as a very large high builds over
southern Quebec. This feature will bring rain free conditions and
east winds for most of the week at least through Thursday with
chances for showers and thunderstorms increasing by next weekend.
Most convection will be offshore with a slight chance indicated
along the diurnal evolution of the northward moving seabreeze Friday
and beyond. Temperatures close to seasonal. 77/blowing dust

Aviation...12z issuance areas of IFR stratus are possible across
portions of south central Alabama and the western Florida Panhandle this
morning. Expect this stratus to remain east of mob/bm...but it is
possible pns could be affected. The stratus is expected to mix out
by 16-18z. Otherwise... VFR conditions are expected through the next
24 hours. 34/jfb

Marine...a strong pressure gradient between high pressure over the
eastern Seaboard and a surface trough over the central Gulf is resulting
in a strong easterly flow this morning. Will maintain the Small
Craft Advisory for the open Gulf waters through midday. Small craft
should exercise caution this morning in area bays. Winds will
gradually diminish this afternoon into Sunday as the pressure
gradient weakens. However...exercise caution conditions will persist
over the Gulf waters this afternoon and evening. Seas of 4-6 feet
continue this morning...gradually subsiding through Sunday.

A period of light winds are expected Sunday night into Monday.
Northeast winds increase by Monday night as a cold front pushes
south into the region. A tight pressure gradient will set up due to
an expansive surface high building over the Ohio Valley into New
England. A prolonged period of moderate to strong NE-east winds are
expected Monday night through middle to late week. This will build seas
into the 5-7 feet range by Wednesday. 34/jfb

&&

Mob watches/warnings/advisories...
Alabama...none.
Florida...none.
MS...none.
GM...Small Craft Advisory until 1 PM Saturday for the following
zones: coastal waters from Destin to Pensacola Florida out 20
nm...coastal waters from Pensacola Florida to Pascagoula MS out
20 nm...waters from Destin to Pensacola Florida from 20 to 60
nm...waters from Pensacola Florida to Pascagoula MS from 20 to
60 nm...

&&

$$

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