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Area forecast discussion 
National Weather Service Huntsville Alabama
320 am CST Tuesday Dec 1 2015

a large cut off upper low continues to rotate around the upper
Midwest with a cold front extending through western Tennessee and
central Mississippi. However a broad stream of moisture originating
from the eastern Pacific is extending across the southern states and
up through the northeast along the base of the upper low. Another
batch of light to moderate rainfall is pressing east across the County Warning Area
as of 09z this morning with more scattered coverage back in central

The forecast question of the day will be how widespread the rain
coverage is today and when will it end. Looks are deceiving with the
current radar coverage being light off to the west. Looks like
another wave develops along the cold front today after 18z with the
help of upper jet support. So once this batch moves through there
could be a brief break in widespread coverage but expecting the
coverage to increase once again this afternoon as the front and
surface wave moves to the southeast. All areas today could receive
another half an inch to an inch of rain. Would also not be surprised
to see a rumble of thunder or two today with the front moving
through but chances are not high enough to warrant the 15 percent
slight chance in the forecast.

Temperatures today will also be a challenge as forecast highs for the area
are actually lower than the current temperatures. It looks like we
are going to hit our highs early in the day and stay steady then
slowly fall through the day as the front makes its way through the
County Warning Area. Therefore...temperatures will not be changing much from the current
values in the lower 60s.

As mentioned above...the cold front will continue to move through
the County Warning Area today with deep layer dry air expected to quickly push into
northwest Alabama after 12-15z Wednesday with the frontal passage. Thinking is
that guidance is holding onto the precipitation a little too long overnight
and am expecting northwest Alabama to be dry 06-09z. However the front is
slow moving and will linger in our southeast counties through at least Wednesday
morning which will lead to higher rainfall values for the counties
currently in the Flood Watch. An additional half an inch to an inch
would be expected tonight in those counties. With the front moving
through tonight...lows will be able to drop into the middle 40s to
lower areas to the east. All areas should be dry by 00z
Thursday as the front is well to the southeast at this time.

Even with plenty of dry air pushing in behind the front...the
previously mentioned stream of low level moisture looks to continue
through at least Thursday morning. This should lead to some
lingering mostly cloudy skies Wednesday and slowly clearing out by
Thursday morning. With the clouds in place and the front through
highs on Wednesday will only get into the middle 50s. Then...went with a
less cloudy forecast for Wednesday night so lows right now are expected to
drop into the lower to middle 30s.

Sunny skies and dry weather finally makes its return for Thursday
afternoon as broad surface high pressure encompasses much of the
eastern United States with highs in the lower 50s. Temperatures will be able
to warm a bit into the upper 50s to near 60 for Friday-Monday as an upper
ridge builds in. Lows will slowly rise and get into the lower 40s for
sun/Monday nights. However we do not really get into a warm return flow
until Monday evening which will help keep temperatures from rising much

We start to see some model differences on Monday on how to handle an
upper trough dropping into the Midwest. Previous model runs were
wetter but the newest ones are coming in drier for Monday. Will keep
the chance probability of precipitation in for right now with how far out it is. But the
best chance to see rain again looks to be Tuesday night into Wednesday as a
surface low develops over the Gulf and brings rain north into the



/issued 1207 am CST Tuesday Dec 1 2015/
for 06z changes to previous aviation forecast reasoning.
South-southeast flow will continue to strengthen early this morning...with
threat for -shra increasing in advance of cold front approaching from
the west. Band of heavier rain showers accompanying this slow-moving cold
front will likely impact mean sea level between 01/07-13z and hsv between 09-15z...
along with IFR ceilings and MVFR visibility reductions. A few embedded thunderstorms and rain
will also be possible...but expected coverage is too low to include in
taf. As front slowly pushes southeastward and winds veer to west-northwest...precipitation will
transition to -ra between 13-15z. Front will likely stall southeast of
the terminals tomorrow afternoon...with -ra/-dz possible through end of taf
period. IFR ceilings and MVFR visibility reductions will also persist through
02/06z as winds will remain light and from the northwest.



Preliminary point temps/pops...
Huntsville 64 49 57 37 / 90 70 40 10
Shoals 60 43 57 34 / 90 50 20 10
Vinemont 63 47 55 34 / 90 70 50 10
Fayetteville 62 46 55 35 / 100 60 30 10
Albertville 65 51 55 36 / 90 80 60 10
Fort Payne 64 50 55 35 / 90 90 60 10


Hun watches/warnings/advisories...
Alabama...Flood Watch through late tonight for alz006-008>010.

Tennessee...Flood Watch through late tonight for tnz076-096-097.



For more information please visit our website
at weather.Gov/Huntsville.

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