Area Forecast Discussion
Issued by NWS Mobile, AL

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
FXUS64 KMOB 162338

Area Forecast Discussion
National Weather Service Mobile AL
538 PM CST Mon Jan 16 2017

.DISCUSSION...Updated for latest aviation discussion below.


00Z issuance...Light southeast winds continue overnight with the
potential for fog and stratus to once again lower vis/cigs to
MVFR/IFR levels by 17.06z, with brief periods of LIFR visibilities
possible in locally dense patches of fog. VFR visibilities and
MVFR/VFR ceilings return late Tuesday morning and prevail through the
remainder of the day along with another chance for a few light
showers and southerly winds around 10 knots. /49


.PREV DISCUSSION... /issued 346 PM CST Mon Jan 16 2017/

NEAR TERM /Now Through Tuesday/...Weather map analysis today shows a
vigorous mid level storm system lifting northeast across the central
plains states with the axis of a short-wave mid level ridge moving
off the southeast US coast. At the surface, the forecast area is
between a 1030 millibar surface high positioned over the Mid-Atlantic
and a cold front draped from east Oklahoma to east Texas. A deep
layer southerly flow continues over the region which supports keeping
night-time lows (upper 50s interior/lower-mid 60s coast) and daytime
highs for Tuesday (mid to upper 70s) well above climatic normals.
Could be some patchy sprinkles tonight, but it appears the chances of
measurable rain are low at less than 10%. Will continue to mention
the development of late night, patchy fog.

For Tuesday, deep layer moisture (pwat~ 1.2 inches) is adequate for
a small chance of showers as mid level impulses in the high level
southwest flow pass across the area which aids in weak lift. Over
the interior northwest, guidance does show some instability in place
(MUCAPE values lifting up to around 600 to 800 J/KG) which supports
making a mention of thunder. /10

SHORT TERM /Tuesday night Through Thursday night/...The weak upper
ridging over the southeast Gulf of Mexico and extreme southeast conus
will continue to get pushed to the south as an upper shortwave over
the midwest states moves east-southeast over the western Atlantic by
Wednesday afternoon. Meanwhile, a closed upper low pressure area
over Arizona, New Mexico, and northern Mexico lifts very slowly
toward the northeast, reaching the central Great Plains by Thursday
evening. An upper trough extending southward from the closed low to
northeast Mexico around noon Thursday will swing northeast, becoming
negatively tilted as it passes very quickly over the region Thursday
night. Weak surface high pressure will remain across the region
through midweek, and then move east of the area as a weak surface low
forming across the Arklatex region on Thursday lifts northeast to
the Ohio River valley by late Thursday night.

A mainly dry forecast is expected Tuesday night, with patchy fog
forming across the forecast area late Tuesday night into Wednesday
morning as southerly winds keep low level moisture in place. Isolated
to scattered coverage of rain showers are then expected Wednesday
into Thursday morning, followed by likely to definite showers and
thunderstorms Thursday afternoon and evening as the upper trough
swing quickly over the region. A few strong storms with gusty surface
winds may accompany the line of storms Thursday afternoon and evening
as a low level jet between 40 to 50 knots passes over the forecast

High temperatures Wednesday will continue to be very warm, ranging
from 73 to 79 degrees. Highs along the beaches will be around 70
degrees. High temperatures Thursday will be in the low to mid 70s.
Low temperatures each night will be in the upper 50s to lower 60s.

LONG TERM /Friday Through Monday/...Upper ridging will rebuild over
the southeast conus on Friday as the upper trough continues to move
northeast away from the area. A second upper closed low is expected
to form over the Texas Panhandle/Oklahoma region this weekend and
move east-northeast over the Ohio River valley region by noon
Monday. An associated surface low pressure area, also forming across
the Texas Panhandle/Oklahoma region, is expected to strengthen as it
moves east-northeast, reaching the Ohio River Valley region during
the same time frame. This will set up another very wet pattern
across our region, with scattered to numerous showers and a chance of
thunderstorms through the weekend, with widespread rainfall amounts
between 2 to 3 inches. A cold front approaching from the west on
Sunday will move through the region late Sunday, bringing drier
conditions back into the forecast area on Monday. Temperatures will
continue to be warm through the weekend, with highs in the lower
70s and lows in the mid 50s to lower 60s. Cooler temperatures are
forecast for Monday with highs in the upper 50s to lower 60s. /22

MARINE...High pressure off the Mid-Atlantic coast sinks southward to
the northern Bahamas on Wednesday. This feature maintains a component
of light onshore flow thru mid week. Not overly confident on degree
of fog and how thick it becomes tonight. A mitigating factor is the
warmer waters over area bays and sounds where temperatures have
recovered to near 61 on average. With dewpoints in the lower 60s
overnight, the thermal differences between the surface base moisture
and the modified water temperatures lean to more of a patchy
representation in fog. Something to watch. The next frontal passage
is expected on Friday, but little in the way of a wind shift with
this one as the flow remains generally south to southwest. Chances of
showers and storms trend higher Thursday into Friday morning. /10




This product is also available on the web at: is the U.S. government's official web portal to all federal, state and local government web resources and services.