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fxus64 kjan 170532 aaa 
afdjan

Area forecast discussion...updated
National Weather Service Jackson MS
1232 am CDT Tue Oct 17 2017

Update...
updated for 06z aviation discussion

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Aviation...
06z taf discussion:
VFR conds will prevail through Tue night. /22/

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Discussion...
forecast remains on track with cooler than average temperatures
expected overnight across most of the area. A few high clouds
remain over the southeastern counties but should gradually push
southeast and out of our area overnight. Winds remain out of the
north and have subsided to generally 5-10 knots across the region
over the past few hours.

Prior discussion below:

Tonight and Tuesday...latest rap and satellite imagery showed a
strong upper trough moving through the eastern Continental U.S.. this was
dragging a cold front east of the region. Unlike yesterday readings
were more seasonable across the region from the middle 60s to the
lower 70s. Gusty winds of up to 20-25 knots was noted across the
region.

For tonight the winds will diminish to less than 10 mph. It will be
a cool night as high pressure builds in from the northwest with
below average lows from near 40 to the middle 40s.

For Tuesday sunny skies and continued cool conditions will be the
general rule with highs from the lower to middle 70s. The surface
high pressure will build across the region from the northwest as
short wave upper ridging tracks across the region. /17/

Tuesday night through the coming weekend:

Consensus of latest model solutions have come in a little more
stoutly with the warm up and also a little more vigorously with
regard to the upper level trough energy digging toward the south-
central states by the end of the week and through the weekend.

The more pronounced ridging aloft before the trough is the biggest
driver of some slight increases in temperatures (in comparison to
the previous forecast) for the Wednesday through Saturday period.
At least Wednesday and Thursday the atmosphere will remain dry
enough to support large (30+ degree f) diurnal ranges and
overnight hours during this period will still be quite cool and
pleasant.

It is quite possible models still do not have the right idea
concerning south-central states trough evolution toward the latter
half of the period, mainly because this trough is the
manifestation of a large surge of Pacific jet stream energy
cascading through the Pacific northwest, and then down the Lee of
a building ridge near of just offshore of Southern California.
Many model solutions have this energy effectively "cutting-off"
near or just to the west of the lower Mississippi Valley by the
start of next week. If this happens then our region could quickly
get into a cloudy, moist, and rather wet pattern. However, there
is certainly still some potential energy will fail to cut off and
could pass quickly to our north, bringing far less (not to mention
more short-lived) rain chances. For now we have kept from going
too aggressive with rain chances toward the end of the forecast
period (next Sunday/monday) but basically had little choice but to
at least start introducing some slight rain chances for many
locations by Saturday. At this point the potential for any
hazardous weather through early next week looks pretty low, but I
would not exactly say it is zero either because there is a lot of
jet stream energy that may dig south if model consensus trends
most aggressively for our neck of the Woods. For now we are
keeping the severe weather potential statement clear and will monitor trends in the forecast
closely. /Bb/

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Preliminary point temps/pops...
Jackson 47 78 49 81 / 0 0 0 0
Meridian 46 77 49 79 / 0 0 0 0
Vicksburg 47 80 49 81 / 0 0 1 0
Hattiesburg 48 77 52 81 / 0 0 1 0
Natchez 49 79 52 81 / 0 0 1 1
Greenville 47 78 48 79 / 0 0 1 0
Greenwood 46 79 47 80 / 0 0 1 0

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Jan watches/warnings/advisories...
MS...none.
La...none.
Arkansas...none.

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