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Area forecast discussion 
National Weather Service Mobile Alabama
631 PM CDT Tuesday Jul 29 2014

Aviation update...expecting light northwest wind below 100 to 200
feet which...with the humidity currently expected to be very low...we
believe there would be a very low risk of suppressed visibility. Some
exceptions cannot be ruled out...small chance of thin layers of
ground fog forming in a few locations especially low lying places and
along river bottoms. Will not mention fog or mist in tafs.


Mesoscale update...expecting decoupling of the boundary layer wind
which...with the humidity currently expected to be very low...we
believe any risk of suppressed visibility is minimal. We cannot rule out
patchy ground fog in a few locations especially low lying places and
along river bottoms that are prone to fog. There are also locations that
received rain Monday night which could see more evapotranspiration
from vegetation. However...the overall risk is minimal again due to
very low humidity and just enough mechanical turbulence near the
surface to keep it well mixed. No changes to the forecast


Previous discussion... /issued 236 PM CDT Tuesday Jul 29 2014/

Short term (tonight and wednesday) doesn't get much better
weather wise for late July than what we are currently experiencing.
Regional observation show middle afternoon temperatures in the middle to upper 80s with
dewpoints dropping into the upper 50s/lower 60s. Dewpoints will
continue to gradually lower through the night. This sets the stage
for an unseasonably cool night for this time of year given mostly
clear skies and light winds. There is a pocket of 850 mb (noted by
area of stratocumulus over central Alabama/ms) that will move south
tonight...but most of the cloud cover is diurnally driven and should
diminish with the loss of heating. Lows are expected to drop into
the upper 50s/around 60 well inland with middle to upper 60s along the
I-10 corridor and around 70 along the beaches. A record low is
forecast for Mobile and Pensacola will be very close as well. Here
are the records...

July 30th record lows
mobile: 67/1968&1994
pensacola: 67/1994

Very dry air will persist across the area on Wednesday with
precipitable waters remaining less than 1 inch. Highs are only
expected to reach the upper 80s over most of the area. 34/jfb

Long term (wednesday night through tuesday)...main upper trough
over much of the eastern Continental U.S. And central Gulf Coast will persists
through early next week...then weaken slowly through middle week. At
the surface weak high pressure will maintain along the central Gulf
Coast through early next week. As a result this pattern will lead to
more unseasonably dry weather through Thursday followed by an increase in
clouds and better rain chances late Friday through early next week. The
best chance for measurable rain will be during the afternoon and
early evening hours through early next week due to daytime heating
combined with better lift or forcing in the middle levels in response
to a series of weak to moderate middle level disturbances rounding the
base of the main upper trough over the region. With continued dry air
aloft combined with moderate instability in the lower to middle
layers of the atmosphere a few storms could be strong of briefly
severe Friday through early next week. For now the coverage still looks
to be mainly scattered through the weekend. As for temperatures will
continue to use a blend of the extend European model (ecmwf) MOS and GFS ensemble
guidance through the period. Highs will mostly range from the upper
80s to lower 90s for most areas through early next week. Lows for
Thursday morning could still be near record levels...mostly in the low to
middle 60s for most areas...then gradually warm each day...lowering to
near seasonable levels sun into early next week. 32/ee

Aviation....VFR conditions are expected through the taf period.

Marine...a cold front will push well south of the marine area
tonight with a light northerly flow expected in the wake of the
front this evening...becoming moderate at times early Wednesday
morning due to cool air drainage from land. The front dissipates
south of the area on Wednesday with a very weak and ill defined
pressure gradient forecast over the region through the weekend.
This results in light winds and low seas. 34/jfb

Fire weather....a weak surface ridge of high pressure will maintain
over the central Gulf states through early next weak. Aloft a
persistent middle to upper trough of low pressure will continue over
much of the eastern United States including the central Gulf Coast
region through early next week. This pattern will lead to much drier
conditions through early Friday followed by a gradual increase in low
level moisture through early next week. As better moisture begins to
advect northward later in the week a better chance for showers and
thunderstorms can be expected over the weekend continuing into early
next week. Although afternoon relative humidity will fall to near of
slightly below critical thresholds for both Wednesday and Thursday
latest 20 foot winds for both days will remain below 10 knots which
is below criteria. As a result a Fire Weather Watch or warning is not
anticipated at this time.

Fog potential and other remarks...patchy fog mostly during the
morning hours near sunrise will be possible over low lying areas
generally inland away from the coast. 32/ee


Preliminary point temps/pops...
Mobile 65 88 65 90 68 / 00 00 05 20 20
Pensacola 68 88 70 88 72 / 00 00 05 10 10
Destin 70 88 72 86 75 / 00 00 05 10 10
Evergreen 60 88 60 90 65 / 00 00 05 10 20
Waynesboro 60 87 62 89 66 / 00 00 05 30 30
Camden 59 87 61 90 66 / 00 00 10 20 20
Crestview 61 91 59 93 67 / 00 00 05 10 10


Mob watches/warnings/advisories...


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