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Area forecast discussion...update to short term 
National Weather Service Mobile Alabama
915 PM CST Wednesday Dec 24 2014



Update...package updated to clean up expired products. Rest of
package generally on track.

/16

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*************** previous issuance 359 PM CST **********************

Short term [tonight through Christmas night]...the cold front has
now moved east and completely cleared the forecast area. As a result...
showers and storms have moved well east of the area...but widespread
middle to high level clouds continue as associated middle/upper level trough
moves over the region. Expect this cloud cover to gradually diminish
and move east overnight as the middle/upper level trough axis moves on
off to the east. For Christmas day...the upper trough axis will be
well east with upper flow becoming nearly zonal and a mostly sunny
day is expected. As far as temperatures go...lows tonight in the low
to middle 30s over all of the interior and in the upper 30s closer to
the coast. Some lower 40s along immediate beach areas. High
temperatures on Christmas day in the upper 50s for almost all
locations...but a few lower 60s will be possible in some areas. 12/ds

Axis of large area of surface high pressure is forecast to be
centered over the Appalachians Christmas night. There may be some
patchy light frost development over the interior northeast zones
after midnight...but question will be onset of clouds. With high
level ridge of high pressure positioned across Cuba and
Hispaniola...a high level southwest flow reforms over the central
Gulf Coast. Within the flow...more clouds are forecast to again be
spreading in from the southwest overnight...which would act to limit
frost development. Overnight lows are forecast to be in the middle 30s
interior to Lower/Middle 40s coast. /10

Long term [friday through wednesday]...very little change noted in
the high level southwest flow which keeps the Gulf Coast on the
cloudy side through the weekend. A series of upper level impulses
embedded in the mean flow aloft...track off to the northeast while
next cold front moves southeast out of the plains and across the
lower Mississippi River valley through the weekend. Considering
modified deep layer moisture...approaching frontal and upper level
forcing...the weekend weather pattern looks wet. Will begin to see
the potential for a slight chance of showers entering the southwest
zones and coastal waters by Friday afternoon...increasing in coverage
Friday night and Saturday. Predominant Mode of weather will be
showers with embedded storms. There is a strong signal in the
forecast guidance showing measurable rains in the 24.12z operational
GFS/ECMWF/and NAM by Saturday...leading to higher confidence in
adjusting probabilities of precipitation to categorical ranges. The
front slows as it reaches the coast on Sunday which will maintain a
good to likely chance of seeing showers and a few storms.

The potentially active southwest aloft over the central Gulf Coast
looks to carry over into the first half of next week as a vigorous
upper level trough sinks across The Four Corners of the Desert
Southwest. At the surface...an inverted trough of low pressure/surface
front draped anywhere from the Texas coast to the central Gulf Coast
provides for a focus for a chance of rain Monday through Wednesday.
Could be a brief break in the rain chances late Monday into
Tuesday...trending slightly higher by Wednesday.

Near seasonable daytime high temperatures Friday will warm to several
degrees above climatology by Sunday (mid 60s interior northwest to closer
to 70 southeast of I-65). As inverted surface front sinks a bit south
of the local area by the middle of the week...daytime highs trend
cooler. Due to a lengthy duration of southeast flow early in the
medium range...overnight lows modify into the middle 50s interior/lower
60s coast by Sunday. Lows trend back down into the middle/upper 30s
interior to middle 40s closer to the coast by Wednesday morning. /10

&&

Aviation...
25.00z taf cycle
middle to high level clouds overnight...but well above critical
heights. Drier low levels of the atmosphere...so no precipitation or fog to
restrict surface visibility at terminals. Primarily a VFR forecast. Light west
winds early tonight becoming more northwesterly late tonight and
Christmas day. 12/ds

&&

Marine...a strong westerly flow over the marine area gradually
diminishing this afternoon and will continue to do so this evening. A
Small Craft Advisory remains in effect through this evening. After
midnight winds are expected to decrease to around 15 knots offshore
with seas initially around 7 to 9 feet subsiding to 5 to 7 feet
overnight. A general light northeast to east flow then expected
Christmas day through late Friday...then becoming more southeasterly
over the weekend. Showers and thunderstorms redevelop over the marine
area this weekend. 12/ds

&&

Preliminary point temps/pops...
Mobile 37 58 41 64 56 / 05 05 00 20 60
Pensacola 42 58 44 63 56 / 05 05 00 10 60
Destin 47 57 45 63 54 / 10 05 00 10 30
Evergreen 35 58 35 62 49 / 05 00 00 10 30
Waynesboro 33 58 36 64 50 / 05 00 00 10 40
Camden 35 58 35 61 47 / 05 00 00 10 30
Crestview 36 60 36 64 52 / 10 05 00 10 30

&&

Mob watches/warnings/advisories...
Alabama...none.
Florida...none
MS...none.
GM...Small Craft Advisory until midnight Thursday for the following
zones: Choctawhatchee Bay...coastal waters from Destin to
Pensacola Florida out 20 nm...coastal waters from Pensacola Florida
to Pascagoula MS out 20 nm...Mississippi Sound...northern
Mobile Bay...Pensacola Bay system...Perdido Bay...southern
Mobile Bay...waters from Destin to Pensacola Florida from 20 to
60 nm...waters from Pensacola Florida to Pascagoula MS from 20
to 60 nm...

&&

$$

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