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Area forecast discussion 
National Weather Service Mobile Alabama
201 PM CDT Sat Jul 12 2014

Short term (tonight and sunday)...a drier slug over the western
half of the forecast area is limiting precipitation at this time. Looking at the GOES sounder
precipitation h20 shots...higher moisture levels are working their way the northwest at this time as apposed to the west. A few last
minute pop adjustments may be needed before package issuance as a

Am expecting the usual pattern of the activity dying off into the
evening with the loss of daytime heating...then refocusing offshore
as a land breeze sets up. upper trough shifts to along the north-central Gulf
Coast...helping with the afternoon precipitation generation as the Gulf
Breeze moves in. Went above the dry GFS solution as a result and
toned the GFS temperatures downward due to the greater precipitation and decreased
afternoon insolation due to thunderstorm blow-off. /16

For Sunday night through Tuesday upper low swings out of
Canada and across the Great Lakes region...bringing the axis of a
longwave trough into the eastern states. An associated deep surface
low well to the north brings a cold front into the southeast states
Monday night and slowly into the forecast area Tuesday into Tuesday
night. A surface ridge over the northern Gulf maintains a southerly
flow ahead of the approaching front and deep layer moisture
increases through the period especially over the interior areas with
precipitable water values of 1.6-1.9 inches increasing to around 2.0
inches by Tuesday. Expect sea breeze initiated convection each day
along with coverage increasing with the frontal boundary moving into
the area on Tuesday. Another feature which may enhance convection
is a deformation zone seen in 300 mb flow with the axis of
dilatation expected to be over the north central Gulf coastal
region. This is more apparent on Monday and in the European model (ecmwf) guidance
but it is difficult at this point to see if this will enhance
convection specifically over the forecast area. Will continue for now
with chance probability of precipitation for Monday and good chance to likely probability of precipitation on
Tuesday...with the higher probability of precipitation over the interior areas with the
frontal boundary. Surface based convective available potential energy increase to around 2000 j/kg
on Monday then around 2500 j/kg on Tuesday. Deep layer shear
remains low so am expecting a few strong storms each day with
locally heavy rainfall possible. Temperatures will mainly be
slightly above seasonable values through Monday then are moderated
somewhat on Tuesday with increased coverage of convection. /29

Long term (wednesday through saturday)...the longwave trough over the
eastern states gradually weakens through the period as upper ridging
rebuilds over the Gulf. The cold front will be located near the
coast early Wednesday morning and moves slowly into the northern
Gulf through Wednesday night then returns into the coastal counties
on Thursday. The front dissipates while continuing slowly northward
on Friday while a surface ridge builds over the northern Gulf and
brings a return to a southerly flow and sea breeze activity to the
forecast area. Chance daytime probability of precipitation continue through the period with
slight chance to chance probability of precipitation each night. Highs on Wednesday and
Thursday will be slightly below normal with overnight lows a few
degrees below normal. Temperatures return to seasonable to slightly
above seasonable values by Saturday. /29


18z issuance...another round of thunderstorms and rain is firing along the Florida Gulf
Coast at this time. Westward extent will be limited by a drier slug of air
over the western section of the forecast area. Another round is possible along
the coast Sunday...with the Gulf Breeze the expected initiator.

General VFR conditions expected through the forecast...except for
localized low MVFR ceilings in the rain. /16

&& expecting a weak synoptic flow over the north-central
Gulf of mex into Sunday...with a more organized onshore flow there
after as a surface ridge builds west over the northern Gulf of
Mexico. /16


Preliminary point temps/pops...
Mobile 71 91 73 92 74 / 20 30 20 40 20
Pensacola 73 90 76 92 76 / 20 30 20 30 20
Destin 78 89 78 90 78 / 20 30 20 30 20
Evergreen 72 93 70 94 72 / 20 30 20 40 20
Waynesboro 70 93 69 94 70 / 10 30 10 30 30
Camden 72 94 71 94 71 / 10 30 20 40 40
Crestview 70 92 71 94 72 / 20 40 20 40 20


Mob watches/warnings/advisories...


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