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Area forecast discussion...updated 
National Weather Service Mobile Alabama
1155 PM CDT Tuesday Jun 30 2015

Aviation...
01.06z issuance...VFR conditions will prevail through the forecast
package...with few-scattered low clouds and broken middle-high clouds. Added a
prob30 group for afternoon convection on Wednesday for MVFR
visibility in and around thunderstorms. /22

&&

Previous discussion... /issued 848 PM CDT Tuesday Jun 30 2015/

Update...decreased probability of precipitation overnight to slight chance, upstream cold
pool did not sufficiently develop and convection dissipating as it
moves into our area despite instability ridge. Mesoscale models have
also caught onto this trend and greatly reduced thunderstorm/shower activity.
Will keep slight chance in forecast mainly due to uncertainty but
suspect convection will remain relatively sparse tonight..especially
after midnight. /08 jw

Previous discussion... /issued 734 PM CDT Tuesday Jun 30 2015/

Update...kept scattered thunderstorms and showers through midnight generally
west of a line from Thomasville, Alabama...south to Orange Beach, Alabama.
Isolated showers east...after midnight thunderstorms and showers become
scattered east of that line and isolated west. Robust major shortwave
trough upstream propagating eastward in the base of the longwave
trough has tapped into the lower level instability and has created
two large areas of convection...one over southern, la and the other
north of Highway 84 across southern Mississippi. The one to the north
looks most impressive as radar indicates an organized cold pool
developing behind it and the gust front propagating east-
southeastward toward are County Warning Area. Current analysis shows a sharp
instability ridge extending from the Gulf of Mexico near the Alabama/MS
border (ml cape 2500 j/kg...surface temperatures low 80s and dew points 70s)
northward along the border. Rap13 and hrrr mesoscale models also
depict this instability (though hrrr is a lot weaker with it 500 to
1000 j/kg) and gradually translate it eastward overnight with
convection occurring along its axis. Tailored current forecast to
follow this trend. /08 jw

Aviation update...predominantly VFR except in and around thunderstorms
tonight. Also can't rule out brief MVFR/IFR ceilings and
visibilities late night and early morning in areas receiving heavy
rainfall overnight.

Previous discussion... /issued 415 PM CDT Tuesday Jun 30 2015/

Short term [tonight and wednesday]...interesting afternoon as a
strong and well defined outflow boundary laid down by storms over the
northwestern portions of the forecast area earlier today raced south across the
region. Wind gusts in the 45 to 50 miles per hour range were common. Some minor
wind damage has been reported...especially across Baldwin
County...primarily trees and power lines. A Severe Thunderstorm Watch
was in effect for southern and eastern portions of the forecast area this
afternoon...now remaining in effect for only the western Florida
Panhandle and area bays...as well as Gulf waters out to 20 nm. With
the aforementioned outflow boundary now well offshore...we will be
canceling the remaining portion of the watch before the afternoon
forecast package issuance. For the evening...rain chances will
diminish...but will advertise for a chance of for showers and storms
to redevelop after midnight tonight and toward daybreak Wednesday as
a weak upper level disturbance moves east across the region in the
flow aloft. With lack of heating and instability...these late night
storms are not expected to be as strong as the ones this afternoon
were. Low temperatures tonight expected to range from the lower 70s
over interior northern counties to the upper 70s down along the
coast.

On Wednesday...the weak upper disturbance is expected to move off to
the east of the region...but a weak surface trough extending from NE-
SW across the area will likely act as low level focus for scattered
showers and storms...most numerous in the afternoon hours. Even with
this focus...with the upper support (what little there was) moving
east and with the atmosphere expected to be not quite as unstable
tomorrow...storms should not be quite as intense as those of today
either. High temperatures tomorrow generally in the lower 90s all
locations. 12/ds

[wednesday night]...moisture will continue to spread into the area
as the upper level trough continues to lift and move east. This will
continue the pattern of scattered showers and storms through the
evening hours. Sticking with 20 to 30 percent probability of precipitation through the
overnight...mainly focused across southern Alabama and northwest Florida
Panhandle. Temperatures will fall into the low 70s inland...hovering
in the upper 70s along the coast. 07/mb

&&

Long term [thursday through monday]...as the pattern across the
Continental U.S. Continues to broaden out through the rest of the work week...
ridging will begin to build back into the region at all levels
for the remainder of the extended forecast. Rain chances will trend
more seasonal with 20 to 30 percent probability of precipitation in the form of scattered
showers and storms each afternoon. Much of this activity will be
focused across the southern portion of the area along the sea breeze.
For now...expecting a few showers and storms to linger beyond sunset
on the Holiday...but a relatively dry forecast expected that evening.

Not much day-to-day change in temperatures expected through the
entire extended forecast as high pressure grips the region. Highs in
the middle to low 90s expected through the Holiday weekend...trending
warmer by early next week. Little change in overnight temperatures
with low 70s inland and upper 70s along the beaches and coastline.
07/mb

&&

Marine...a ridge of high pressure over the northern and eastern
Gulf of Mexico will continue through the remainder of the week and
into the weekend. This will promote a light to moderate
southwesterly flow over the marine area through the period. The
ridge of high pressure will also keep most of the shower and
thunderstorm storm activity over the next several days over interior
sections of the southeast and generally away from the marine area.
However...some scattered showers and storms will be possible over
the coastal waters...with locally higher winds and seas. 12/ds

&&

Preliminary point temps/pops...
Mobile 75 90 74 91 75 / 20 50 20 30 10
Pensacola 77 89 75 90 77 / 20 40 20 30 20
Destin 79 88 78 89 79 / 20 30 20 30 20
Evergreen 72 90 72 91 72 / 20 40 30 40 20
Waynesboro 72 90 72 92 71 / 20 50 30 30 10
Camden 72 90 72 90 72 / 20 40 30 40 20
Crestview 74 91 72 92 73 / 20 30 30 30 20

&&

Mob watches/warnings/advisories...
Alabama...high rip current risk through Thursday morning for Baldwin
coastal-Mobile coastal.

Florida...high rip current risk through Thursday morning for Escambia
coastal-Okaloosa coastal-Santa Rosa coastal.

MS...none.
GM...none.
&&

$$

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