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Area forecast discussion...updated 
National Weather Service Mobile Alabama
749 am CDT Friday Aug 28 2015

Update...the temperature dropped to 66 degrees at the Mobile
regional Airport this morning. This tied the record low for Mobile
originally set in 1992 and equaled in 2013. /22

&&

Previous discussion... /issued 644 am CDT Friday Aug 28 2015/

Aviation...
28.12z taf issuance...VFR conditions forecast in the near term. A
few thunderstorms and rain may pop up over the western Florida Panhandle by middle
afternoon. Light north northeast winds this morning...become
southeast into the afternoon. /10

Previous discussion... /issued 403 am CDT Friday Aug 28 2015/

Short term [today and tonight]...on the weather maps...a deep upper
level trough extends from the Appalachians to the central Gulf. Water
vapor imagery shows a considerable amount of dry air. This is
reflected in latest 28.00z radiosonde observation data across the central Gulf Coast
which shows pwat's to around an inch. When comparing to climatology
for late August...precipitable waters are way down to around 2 Standard deviations
below seasonal normals. East of the high level trough axis...a quasi-
stationary surface frontal boundary was draped from off the
southeast US coast to deep into the southern Gulf.

For today...the southern branch of the high level trough develops into
a cutoff low which moves little over the northern Gulf. The far
eastern zones may have a small opportunity to see a slight chance of
showers and storms by this afternoon and tonight as these areas will
be on the favored east side of the trough where modest lift exists and
a gradual return of deep layer moisture sets up as Atlantic moisture
is pulled westward. The western half of the local area looks to
remain rainfree in the near term. Light northerly flow this morning
becomes southeast in the afternoon with daytime highs mostly in the
lower half of the 90s. Light east southeast flow overnight with lows
ranging from 65 to 70 interior and 70 to 75 closer to the coast. /10

This afternoon's wet microburst risk is unlikely

[weekend]...an Upper Cutoff low over the north central Gulf of
Mexico will lift northward over the weekend and merge with an upper
shortwave passing over the upper Midwest and lower Great Lakes
region. However a residual upper trough will remain on Sunday from
the Great Lakes to eastern Texas...with upper high pressure systems
to the west and east of the trough. A southerly wind flow will allow
precipitable water (pw) values to range from 1.4 to 1.7 inches east
of the Tombigbee river on Saturday...and between 1.1 to 1.4 inches
west of the river. By Sunday...the precipitable water values will range from 1.4 to
1.7 across the entire forecast area. The National Hurricane Center
has tropical cyclone Erika making landfall across the southern tip
of Florida Sunday evening as a tropical storm.

Rain chances will increase on Saturday...with scattered showers and
thunderstorms (30-50 percent) east of a line from Butler Alabama to
Pensacola Florida...and isolated showers and thunderstorms to the
west of this line. Slightly lower coverage is expected on Sunday...
ranging from little to no rain across our Mississippi zones to a 30
percent chance across our far eastern zones. Patchy late night fog
should develop each night.

High temperatures over the weekend will range from 86 to 91 degrees.
Low temperatures over the weekend will range from 68 to 73 degrees
inland areas...with middle 70s along the immediate coastal sections. /22

Long term [monday through thursday]...the National Hurricane Center
has tropical cyclone Erika moving north-northwest over the southern
Florida Peninsula on Monday...and over the northern Florida
Peninsula on Tuesday. If the forecast track keeps Erika to our
east...a gradual decrease in moisture through the remainder of the
long term is expected as winds turn back to a northern flow.
Subsidence along the western periphery of Erika will also cut down
our rain chances. For now have isolated showers and thunderstorms
southeast of I-65 on Monday...with no rain to the northwest of I-65.
Isolated to low end scattered showers and thunderstorms are expected
through the remainder of the long term...mainly during the daytime
hours. High temperatures will still manage to reach the lower 90s
each day inland areas...with upper 80s along the immediate coastal
sections. /22

Marine...surface high pressure moves east into the
Appalachians this weekend...resulting in the development of a light
onshore flow. The surface high remains in place into the first half
of next week. Little change in seas. Meanwhile...Tropical Storm Erika
is forecast by the National Hurricane Center to approach the southern
tip of Florida by late Sunday night and lift north northwest across
the Florida Peninsula on Monday. Erika is rather disorganized at
present. The future track...strength and storm structure will be
highly dependent on how Erika interacts with an environment
characterized by high shear and the high terrain of Hispaniola in the
near term. /10

&&

Preliminary point temps/pops...
Mobile 90 69 88 69 90 / 05 10 20 20 20
Pensacola 90 73 87 73 88 / 10 20 30 20 20
Destin 89 75 87 75 88 / 20 30 40 30 30
Evergreen 93 70 88 68 90 / 20 20 40 20 20
Waynesboro 93 66 89 68 91 / 00 10 20 05 20
Camden 93 70 87 69 90 / 10 10 40 05 20
Crestview 92 69 88 70 90 / 20 30 40 20 30

&&

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

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