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fxus64 kmob 140501 aac 

Area forecast discussion...updated
National Weather Service Mobile Alabama
1201 am CDT Mon Oct 14 2019

Discussion...updated for latest aviation discussion below.


06z issuance...predominately VFR conditions are expected through
the period, although some locations will occasionally see MVFR
ceilings. Isolated showers will be possible through much of the
period. Light northerly winds become northeasterly around 5 knots
on Monday, except for near the coast where a southerly flow is
expected to develop Monday afternoon. /29


Previous discussion... /issued 1012 PM CDT sun Oct 13 2019/

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

Update...have updated to lower pops to slight chance for most of
the area for the rest of the night. Made other minor adjustments.

Previous discussion... /issued 623 PM CDT sun Oct 13 2019/

Discussion...updated for latest aviation discussion below.

00z issuance...VFR conditions are expected to prevail through the
period with isolated showers possible. Light northerly winds
tonight will become northeasterly around 5 knots on Monday, which
may become southerly near the coast Monday afternoon. /29

Previous discussion... /issued 400 PM CDT sun Oct 13 2019/

Near term /now through Monday/...a zonal upper flow pattern
combined with surface high pressure to the north of the area will
keep the stalled boundary near the coast through Monday. The
combination of low level forcing along the boundary, upper level
disturbances moving from west to east in the zonal flow, and
increasing moisture off the Gulf will keep the risk of isolated to
scattered rain showers and a few thunderstorms tonight through
Monday. Lows tonight will range from from the upper 50s and low 60s
well inland to around 70 near the coast. Highs on Monday will be in
the upper 70s and low 80s inland to low to mid 80s along the coastal
areas. /13

Short term /Monday night through Wednesday night/...a nearly
stationary surface front that will still be situated down near the
coast very early Monday evening should be lifting northward
across the forecast area late Monday night through Tuesday night.
Meanwhile, a strong cold front will be approaching the forecast
area from the northwest by Tuesday night. Zonal upper level flow
will remain over this boundary through the short term, with
occasional shortwave disturbances moving east in this zonal upper
flow. The combination of low level forcing along the surface
boundary, the upper level disturbances moving from west to east in
the zonal flow, and increasing moisture off the Gulf (pwats
increasing to the 2.00 to 2.20 inch range across the area) will
result in increasing rain chances from late Monday night and
continuing through Tuesday night and the stronger cold front
approaches from the west. Some heavy rainfall could be possible
across the area from late Monday night through Tuesday night, but
there is some disagreement in model guidance (specifically
between European model (ecmwf) and gfs) as to where the heavier rainfall will
occur. Primary GFS runs have been consistent in keeping the axis
of heaviest rainfall across central portions of Alabama just to
the north of our forecast area, whereas the European model (ecmwf) suggest two
bands of heavier rainfall, one to the north of our area but
another across northern interior portions of our forecast area.
One to two inches of rainfall across most of the area appears to
be likley through the short term period, with the possibility of 2
to 4 inches across interior southwest Alabama. Wpc has the far
northern portions of our forecast area outlooked for a slight
possibility of excessive rainfall, and we will continue to monitor
model forecast trends for an increased possibility of excessive
rainfall over our area (which would primarily be of concern on
Tuesday and Tuesday night should it occur). We will go ahead and
advertise a limited threat of flooding rains over northern third
of our forecast area for the threat of localized flash flooding.
During the day on Wednesday things begin to improve rain-wise as
the stronger cold front to our west sweeps east across the area,
bringing a return of drier and cooler air to the region. Lows
Monday and Tuesday night ranging from the mid 60s inland to the
mid and even a few upper 70s coastal, cooling to upper 40s and
lower 50s inland and upper 50s to lower 60s coastal by Wednesday
night in the wake of the front. Highs on Tuesday and Wednesday
mainly in the 70s and 80s (but likely beginning to cool northwest
counties Wednesday afternoon as the front moves through). /12

Long term /Thursday through Sunday/ and dry high pressure
drifts east across the region Thursday and most of Friday, with
mostly clear skies and no rain expected. By early Saturday through
Sunday, a moist return flow of the Gulf develops bringing moderating
temperatures again as well as increased rain chances. Highs Thursday
in the 70s across most of the region, warming to the 80s by the
weekend. Thursday night lows ranging from the upper 40s far north,
50s central portions of the forecast area, and around 60 at the
coast. Lows warming into the lower to mid 60s inland to lower 70s
coastal over the weekend. /12

Marine...a stalled frontal boundary will remain along or south of
the coast through Monday before moving inland Monday night and
Tuesday. A light to at times moderate offshore flow north of the
front with east to southeasterly flow south of the front will last
through Monday before becoming a general onshore flow on Tuesday.
Another cold front will move over the area Wednesday into Wednesday
night, bringing a return of offshore flow by Thursday. /13


Mob watches/warnings/advisories...

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