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Area forecast discussion...updated 
National Weather Service Mobile Alabama
926 PM CDT sun Mar 29 2015

Update...the overall forecast tonight is in good shape and no
significant changes are anticipated. Overnight low temperatures still
look on track to fall into the upper 40s to lower 50s inland to the
middle 50s to around 60 near the coast.

02z surface analysis shows a cold front stretching from west and
North Texas northeastward through central portions of OK/southeast Kansas
and into the upper midwestern states. The latest short term guidance
indicates that this feature will push southward and will extend into
the south central portions of MS/al/GA by late Monday afternoon. The
latest NAM forecast soundings continue to show an increasingly
unstable airmass across our forecast area Monday afternoon...with
MLCAPE values rising to around 1000 j/kg...and perhaps locally
enhanced between 1500-2000 j/kg near the surface boundary and the
seabreeze Monday afternoon. Deep layer shear will average between
30-40 knots in the 0-6 km layer. Although deep layer moisture will
be limited and upper forcing rather weak...enough buoyancy along the
approaching boundary will be sufficient for isolated to scattered
thunderstorms across our region. With fairly low wet bulb zero
heights between 7500-9500 feet above ground level and 700-500 mb lapse rates
approaching 7-7.5 c/km...a few storms could strengthen to severe
limits with large hail and gusty winds along the boundaries. We have
updated the severe weather potential statement to add mention of the strong to marginally severe
storm potential Monday. /21


Previous discussion... /issued 729 PM CDT sun Mar 29 2015/

30.00z terminal forecast discussion...
mostly VFR conditions to start off this forecast period...though
patchy regions of broken MVFR to VFR stratocumulus will continue to
develop tonight. Patchy MVFR fog could develop late tonight and early
Monday morning. A weak cold front will move into the forecast area
Monday...and expect isolated to scattered rain showers/thunderstorms and rain to develop near
this feature during the afternoon.

Previous discussion... /issued 336 PM CDT sun Mar 29 2015/

Short term (tonight through Tuesday night)...a broad surface ridge
of high pressure over the middle Atlantic region and eastern Seaboard
will drift south then west through Monday afternoon. Aloft a
weakening middle to upper level short wave trough will continue to move
eastward and dampen across the northern Gulf states through
Monday...leading to better clouds overnight and on Monday for most areas
along with slight chance to chance probability of precipitation across most of the forecast
area mostly during the daylight hours. The best chance of rain will
be generally north of the I-10 corridor during the late morning and
early afternoon hours. Latest model guidance depicts marginal
instability across the region during the day on the Monday combined with
decent vertical shear early in the day followed by better directional
shear mostly from the southwest by afternoon. As mentioned above middle
level forcing will remain limited. As for temperatures will lean towards the
current mav guidance through Monday afternoon adjusting slightly for
consistency with surrounding weather forecast offices. Lows tonight will range from the
middle 50s over western and coastal sections of the County warning forecast area and the
upper 40s to lower 50s to the north and east of kmob. Highs on Monday
will climb to the upper 70s to lower 80s for most inland areas and
the middle 70s along the the immediate coast. 32/ee

A front will stall across the northern and eastern portions of the
forecast area Monday night...with the boundary lifting backing to the
north and weakening Tuesday into Tuesday night. Aloft...middle to upper
level northwest flow Monday night will become semi-zonal by Tuesday.
No significant shortwaves are expected to impact the area through
this time. Therefore...any chance for showers or thunderstorms will
be diurnally driven. This results in just a slight chance of rain
Monday night...followed by 20-40% chances for showers and
thunderstorms Tuesday...with the highest chances occurring over the
northern zones in closer proximity to the lingering frontal boundary
as MLCAPES climb to 750-1500 j/kg during the afternoon hours. A
chance for storms will linger over the same areas Tuesday evening due
to residual instability. Temperatures will climb to above normal levels with
Tuesday highs in the upper 70s to lower 80s with lows Tuesday night
dropping into the upper 50s to lower 60s. 34/jfb

Long term (wednesday through sunday)...a shortwave originating from
the eastern Pacific will become embedded in the semi zonal
flow...approaching the area on Wednesday and moving across on
Thursday. This feature will maintain a chance of showers and
thunderstorms for both days...particularly during the afternoon where
diurnal heating will maximize instability values. Rain chances
diminish on Friday in the wake of the shortwave. However...rain
chances increase once again Friday night into early Saturday as a
cold front moves into the area. There are still some small timing
differences in regard to the frontal passage. However...a return to
more seasonable temperatures and lower humidity values is expected
for the majority of the weekend in the wake of the frontal passage.

29/18z issuance...mostly MVFR to VFR ceilings and visibilities through
30.18z. Lower clouds and patchy fog will occur overnight and early
Monday morning. Winds will shift southeast at 8 to 12 knots with
possible higher gusts during the afternoon and early evening hours
shifting...diminishing to 4 to 6 knots overnight and early Monday
morning then becoming mostly southwest at 8 to 12 knots late Monday
morning through Monday evening. 32/ee

Marine...a broad surface ridge of high pressure over the middle
Atlantic region will shift south over the western Atlantic and
eastern Gulf through midweek. A light to moderate southerly wind
flow will persist through early Tuesday then shift mostly southwest
by midweek as high pressure builds west over the north central Gulf.
A few isolated showers or thunderstorms will also be possible mostly
near shore and over inland bays and sounds Monday through midweek.


Preliminary point temps/pops...
Mobile 58 80 58 80 61 / 05 20 20 20 10
Pensacola 56 79 61 79 64 / 05 30 20 20 10
Destin 57 74 62 76 65 / 05 30 20 20 20
Evergreen 51 81 54 81 59 / 05 40 20 30 30
Waynesboro 55 80 55 82 58 / 10 30 20 20 30
Camden 52 78 53 81 58 / 10 50 20 30 30
Crestview 49 82 57 82 61 / 05 30 20 30 20


Mob watches/warnings/advisories...


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