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Area forecast discussion 
National Weather Service Mobile Alabama
413 am CST Tuesday Feb 9 2016

Near term /now through Tuesday night/...a deep longwave trough over the
eastern states begins to both weaken slightly and shift eastward
tonight. This remains an impressive upper trough and is about 3
Standard deviations below climatological norms over the extreme
southeast states followed by modest weakening tonight. A tight
surface pressure gradient will be present over the forecast area
today which looks sufficient to support Wind Advisory conditions
especially considering the hrrr guidance. Have issued a Wind
Advisory beginning middle morning and continuing through the late
afternoon for the entire area. Deep layer dry air will otherwise be
in place with dry conditions continuing through tonight. Highs
today will range from the middle 40s well inland to around 50 closer to
the coast. Lows tonight will be cold and range from the Lower/Middle
20s inland to near 30 at the coast. /29

Short term /Wednesday through Thursday night/...Wednesday through
Wednesday night...the shortwave energy in the upper trough over the
western Continental U.S. Moves though...shifting the trough axis east. The
upper ridge over the western Continental U.S. Remains put...though. A weak
shortwave working its way southeast over the plains works with a
semi-stationary boundary that has set up over the central
Continental U.S....running from the northern US rockies southeast to NE Florida
and unseasonably warm temperatures over the plains to create and move
southeast a weakly organized surface low over the plains. This puts a
surface high over Texas east-southeast over the northern Gulf of Mexico and
ultimately restoring onshore flow over the lower Mississippi River
valley and the forecast area. This results in temperatures warming from well below
seasonal Wednesday (highs in the low to middle 50s) to less below
seasonal (lows in the upper 20s inland to around 40 along the coast)
Wednesday night. A very dry airmass over the forecast area and surrounding areas
has to significantly moisten up...allowing for the larger than
seasonal diurnal curve.

Thursday through Thursday night...the weak shortwave swings
through...pushing a weak re-enforcing front near the northern Gulf
Coast by Friday morning. The continued onshore flow brings temperatures well
above seasonal...with highs Thursday in the middle to upper 60s...and
lows Friday night in the low to middle 40s over most of the forecast area...upper
30s northern parts of the forecast area as cooler air starts to move back of the
forecast area.

/16

Long term /Friday through Monday/...Friday through Saturday...
shortwave energy moves through the eastern Continental U.S. Upper trough...
pushing a more substantial re-enforcing front across the forecast area Saturday.
Temperatures Saturday and Saturday night continue to be well above
seasonal...with highs Saturday in the 60s...lows Saturday night in
the upper 30s north to middle 40s closer to the coast. Highs Saturday
see the effects of the cooler air......with temperatures rising into the
lower to upper 50s across the forecast area.

Saturday night through Sunday...more upper energy moves southeast
across the plains to over the middle (ecmwf)/upper (gfs) Mississippi
River valley...pushing surface high pressure from over the plains to
over the East Coast. With the divergence in the upper pattern comes a
divergence in the resultant temperatures. The more southerly track of the
European model (ecmwf) results in a warmer forecast...with a surface low forming and
move farther south than the GFS. With the European model (ecmwf) ensembles hinting at
a cooler forecast and the GFS ensembles advertising a warmer
forecast...have went between the GFS and European model (ecmwf) for the forecast.
Temperatures Saturday night in the upper 20s to low 30s expected...with
highs Sunday ranging from around 50 to the middle 50s.

Sunday night through Monday night...the differences between the GFS
and European model (ecmwf) really stand out. With the more southerly track of the rack
of the shortwave Saturday night through Sunday...along with a
speeding up of energy moving into a deepening upper trough over the
eastern Continental U.S....the European model (ecmwf) is advertising rain crossing the area
Sunday night into Monday...whilst the slower/more northerly GFS is
advertising the rain in the late Monday through Monday night time
frame. Have went with an in between passage centering on Monday. Have
also went in between with the temperatures...with the GFS and European model (ecmwf)
ensembles advertising an in between solution. Lows Sunday and Monday
nights generally in the 35 to 40 degree range. Highs Monday in the
50s....with a chance of rain.

/16

&&

Marine...gale conditions due to strong northerly winds will
continue over the open Gulf waters through early afternoon with
Small Craft Advisory winds over bays and sounds. A Small Craft
Advisory follows for the entire area later this afternoon through
tonight...then for the open Gulf waters Wednesday morning as the
offshore flow gradually subsides through Wednesday. A moderate
westerly flow develops Wednesday night and continues a cold front
moves through Friday night with a moderate to strong offshore flow
in the wake of the front. /29

&&

Preliminary point temps/pops...
Mobile 51 29 53 38 / 0 0 0 0
Pensacola 52 30 53 39 / 0 0 0 0
Destin 52 33 52 40 / 0 0 0 0
Evergreen 48 25 51 30 / 0 0 0 0
Waynesboro 48 23 52 28 / 0 0 0 0
Camden 46 24 50 28 / 10 0 0 0
Crestview 50 26 53 29 / 0 0 0 0

&&

Mob watches/warnings/advisories...
Alabama...Wind Advisory from 9 am this morning to 5 PM CST this afternoon
for alz051>060-261>266.

Florida...Wind Advisory from 9 am this morning to 5 PM CST this afternoon
for flz201>206.

MS...Wind Advisory from 9 am this morning to 5 PM CST this afternoon
for msz067-075-076-078-079.

GM...Small Craft Advisory from 1 PM this afternoon to noon CST
Wednesday for gmz650-655-670-675.

Gale Warning until 1 PM CST this afternoon for gmz650-655-670-
675.

Small Craft Advisory until 6 am CST Wednesday for gmz630>635.

&&

$$

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