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Area forecast discussion
National Weather Service Huntsville Alabama
230 am CST Fri Nov 24 2017

Near term...(today)
issued at 230 am CST Fri Nov 24 2017

Another pleasant day across the Tennessee Valley! The morning will
start out chilly with 2am temps in the upper 20s to lower 30s. For
today, surface high pressure will move off to the east and winds
will turn southwesterly. That, plus weak mid level ridging will
usher in a slightly warmer air mass. Sunny skies will also help and
highs will be warmer than previous days, in the lower 60s.

Short term...(tonight through sunday)
issued at 230 am CST Fri Nov 24 2017

An upper trough will dig into the Midwest tonight with a surface low
well north of the Great Lakes, dragging a cold front south of it.
Clouds will be on the increase after midnight with an increase
mostly in the mid and upper levels. Soundings show a decent amount
of dry air below about 700mb through the day and no rain is expected
with this front. Highs will be a deg or two cooler than Friday due
to the cloud cover. The front should be through northwest Alabama around 3-6pm
and out NE Alabama by 6-9pm with winds quickly shifting to the northwest and
cooler and drier air filtering in. Guidance is keeping lows in the
mid to upper 30s due to the slow filtering in of the lower dew
points.

Even with an upper trough and general northwest flow moving through the
area, mid level ridging and surface high pressure building in from
the west will keep temps from cooling too much behind the front. The
coldest air won't make it too far south and will mostly impact our
northern counties. So temps on Sunday, will only be a deg or two
cooler than Saturday, in the upper 50s to around 60. Sunday night
will see good radiational cooling conditions so lows will fall back
near freezing.

Long term...(sunday night through thursday)
issued at 230 am CST Fri Nov 24 2017

Strong dome of high pressure will be settling ewd across much of the
southeast region as the new work week begins. Upper trough axis will also
be exiting to the east and weakening, as a weak upper ridge pattern
quickly moves ewd out of the srn plains states. This should translate
into a continuation of quiet wx conditions, as a brief warming trend
develops over the region. Highs on Mon look to climb mainly into the
lower 60s, while lows that night trend predom in the upper 30s. The
brief warming trend will continue into the middle of next week, as
the sfc high shifts ewd into the mid/srn Atlantic basins and a return
flow pattern develops across most of the cntrl Gulf states. Highs
both Tue/Wed look to rebound well into the mid 60s, while lows both
nights trend more in the mid 40s.

The latter half of the global model runs are still hinting at another
cold front sweeping thru the region around/right after mid week. With
the return flow pattern in place, Gulf moisture and cloud cover will
be on the increase Wed along/ahead of the oncoming front. There
remains some timing discrepancies between the latest European model (ecmwf) and GFS
models, with the GFS solution remaining the faster model by some 24
hrs or so. Maintaining a persistence forecast trend will have the
front moving sewd out of the plains states and thru the cntrl Tennessee
Valley in the late Wed/early Thu time frame. Given the moisture
return and weak synoptic lift along the approaching front, rain
chances or showers remain in the latter part of the forecast package
from Wed thru Thu, with the precip tapering off to the southeast Thu
afternoon/evening.

Slightly cooler air will then stream into the region in the wake of
the frontal passage late Thu into Fri, as highs fall back into the
lower 60s on Thu and then trend below 60f by the end of the work
week. Lows may also fall below the 40f mark by the end of the week,
as another strong dome of high pressure out of the srn/mid plains
takes aim at the southeast states.

&&

Aviation...(for the 06z tafs through 06z Friday night)
issued at 1132 PM CST Thu Nov 23 2017

VFR conditions expected at khsv/kmsl taf sites over the next 24
hours. High pressure axis is moving across the area resulting in a
clear sky and lgt/vrb winds. Winds will shift from the south-southwest as the
ridge moves to the southeast by about 16z.



&&

Hun watches/warnings/advisories...
Alabama...none.
Tennessee...none.
&&

$$

Near term...line
short term...line
long term...09

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