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Area forecast discussion...updated 
National Weather Service Jackson MS
532 am CST Tue Dec 6 2016

updated for 12z aviation discussion


12z taf discussion:
rain is now exiting the region, but a stratus deck will persist
through much of the taf period. Right now ceilings generally range
from LIFR and IFR northwest to MVFR southeast. We'll see a mix of
these categories continue through the day, with more breaks possible
this afternoon and evening. Overnight, ceilings are expected to lower
again at most terminals to IFR/LIFR. Patchy visibility reductions are
also possible tomorrow morning. /Dl/


today/tonight: light to moderate shower activity continues along the
Highway 82 corridor this hour as a mid level shortwave pivots
through the region. This activity will continue to taper off through
the morning as the shortwave continues away from the area. Temps
have actually increased overnight in southeast quarter of the County Warning Area as the
warm sector finally infiltrated that area. However, there is still
virtually no instability, and upper level support for additional
convective development continues to retreat.

Low clouds will stick around for much of the day as low level
cyclonic convergence makes the most of moisture persisting in the
sub 850 mb layer. This will hold temps down again today, with a
small diurnal range from this morning's lows to today's highs. Flow
will become more divergent from west to east during the late
afternoon/early evening, which should allow the stratus to begin to
break up some. However, interminable low level moisture will allow
considerable coverage of clouds to remain through tonight. Weak but
steady cold air advection will yield seasonably cool conditions Wednesday morning.

Wednesday through Monday...Wednesday morning a weak dry cold front
will be stalled along the Highway 82 corridor. There may be a few
sprinkles by afternoon along this stalled front but, light rain
chances will increase Wednesday night ahead of a much stronger cold
front that move into our northwest most zones during the evening
and then push south of our area before noon Thursday. Breezy north
winds in the wake of this cold front usher in much colder and drier
air. Highs Thursday will be held in the 40s at most locations. The
center of the cold airmass, a 1040mb high will become centered over
the Central Plains by Friday morning. This will bring US some of the
coldest temperatures so far this season with morning lows in the low
to mid 20s. Normal lows run in the upper 30s. A north wind of 5 to 10
mph will likely continue Thursday night as temperatures drop into the
20s. This will result in wind chill temperatures in the teens.
Although these wind chill temperatures will be above local advisory
criteria precautions should be taken to limit exposure to outdoor
pets and animals. The large surface high will shift east across our
County Warning Area Friday becoming centered over the southern Appalachians by
Saturday morning. Coldest temperatures will be over east Mississippi
where lows will again be in the lower 20 with mid to upper 20 west.
Friday and Saturday mornings will be the coldest mornings of the
period. The surface high will continue shifting east Saturday
resulting in return flow back across our region. Zonal flow aloft
Saturday will back slightly Sunday ahead of the next approaching
shortwave. The GFS is faster and stronger with the shortwave trough
and surface cold front than the European model (ecmwf) but, rain chances return to our
County Warning Area Sunday and continue into Monday morning until the front moves
through. A return to cooler and drier weather is expected Monday
through Tuesday. /22/


Preliminary point temps/pops...
Jackson 55 43 61 41 / 11 5 7 41
Meridian 57 43 61 44 / 12 5 3 28
Vicksburg 55 42 60 41 / 9 7 9 41
Hattiesburg 61 46 66 48 / 7 3 3 23
Natchez 57 46 63 42 / 6 7 9 43
Greenville 54 40 54 36 / 11 6 11 33
Greenwood 54 39 56 37 / 17 7 9 31


Jan watches/warnings/advisories...




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