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fxus64 kmob 220458 aac 

Area forecast discussion...updated
National Weather Service Mobile Alabama
1158 PM CDT Wed Aug 21 2019

Discussion...updated for latest aviation discussion below.


06z issuance...VFR conditions under light southerly winds are expected
through the rest of the night over most of the forecast area.
Convection is expected to develop south of the coast later
tonight and possible affect near coastal areas, bringing localized
MVFR level cigs and visbys. Some showers may work their way as
far north as i10. A lull in convection is expected mid-morning
into early afternoon, until afternoon showers and thunderstorms
form and bring localized MVFR conditions. A south winds around 10
knots is expected to develop late morning and last through the
afternoon before easing in the evening. /16


Previous discussion... /issued 858 PM CDT Wed Aug 21 2019/

Discussion...see updated information for land areas below.

Update...only minor adjustments made to the forecast to capture
current trends and to add some patchy, overnight fog development
over primarily inland areas. /08

Previous discussion... /issued 633 PM CDT Wed Aug 21 2019/

Discussion...updated for latest aviation discussion below.

00z issuance...general VFR conditions were noted across the area
with a few showers and thunderstorms at the beginning of the
forecast. The current convection will continue to decrease in
coverage and strength into the evening hours and should minimally
impact operations. A general southeast to south wind around 10
knots will quickly become light.

Convection forming offshore late tonight will affect near coastal
areas, with low to mid level MVFR conditions possible south of
i10. Scattered afternoon convection is possible Thursday, with
general VFR conditions and local MVFR conditions possible in the
stronger convection. Impacts to operations are possible at time.
Light winds starting the day will become a southeast to southerly
5 to 10 knots, a bit stronger along and south of i10.

Previous discussion... /issued 320 PM CDT Wed Aug 21 2019/

Near term /now through Thursday/...a large east-west oriented upper
trof located mainly over eastern Canada takes on a more meridional
orientation while advancing into the interior eastern states through
Thursday. An upper ridge over the western Atlantic, extreme
southeast states and northeast Gulf also extends across the south
central states but weakens over this pattern portion with the
movement of the upper trof. This pattern maintains a light
southerly flow aloft along with some modest embedded shortwaves. At
the surface, a light southerly flow is expected as well during the
period as a surface ridge remains in place over the northern Gulf.
Deep layer moisture will be elevated with precipitable water values
around 2 inches, values which are about 125% of normal. MLCAPE
values increase to around 1500 j/kg on Thursday while shear values
remain very low and wet bulb zero values will be fairly high - near
14-15 kft. Will have small pops over interior areas for lingering
convection early this evening, then mainly dry conditions follow for
the rest of the night except for isolated convection developing near
the coast late tonight. Scattered convection develops across the
entire area on Thursday with daytime heating. Lows tonight will be
in the lower 70s except for mid 70s at the coast. Highs on Thursday
range from the lower 90s well inland to the upper 80s closer to the
coast. A moderate risk of rip currents continues through tonight
with a low risk expected for Thursday. /29

Short term /Thursday night through Saturday night/...a surge of deep,
tropical moisture will move into the area late in the week on the
western side of sfc high pressure. This will maintain an unsettled
weather pattern as precipitable water values climb to 2.25 inches on
Friday. Meanwhile, a weak upper level weakness becomes more
pronounced through the period as a shortwave trof develops over
the central Gulf Coast. As a result, scattered to numerous
showers and thunderstorms will continue each day. Showers
and thunderstorms will be diurnal in nature, starting near the
coast in the morning and spreading inland through the late
morning and afternoon hours. Convective coverage will be most
numerous over the land areas during peak daytime heating, and more
numerous offshore during the overnight hours. The upside to the
fairly widespread rain and associated clouds will be that daytime
temperatures will closer to normal, with highs in the upper 80s to
lower 90s. Lows will continue to range from the lower 70s over
inland locations to the mid/upper 70s closer to and along the
coast. /13

Long term /Sunday through Wednesday/...very little change in the
pattern through the extended range as plenty of deep layer
moisture will continue across the Gulf Coast with precipitable
water values generally remaining over 2 inches. This will
continue the pattern of diurnally driven scattered to locally
numerous showers and thunderstorms each day. /13

Marine...a light and predominately southerly flow is expected
through the period. Seas will be mainly 1 to 2 feet. /29


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