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Area forecast discussion...corrected 
National Weather Service Jackson MS
404 PM CDT Tuesday Sep 30 2014

Short term...partly cloudy skies prevail across the arklamiss this
afternoon as surface/upper ridging prevail. There could be a few
isolated showers this afternoon and early evening in the southwest.
Little will change tonight...but the flow will become more
southeasterly than southerly by Wednesday morning. Precipitable waters will climb
through the day on Wednesday and will range from near 2.0 inches in
the south to around 1.5 inches in the north. With the increase in
moisture combined with daytime heating there could be a few showers
and possibly a thunderstorm Wednesday afternoon mainly for the
central and southwestern portions of the area.

With a continuation of the southerly moist flow Wednesday night
there will continue to be a slight chance of showers through the
night. Upper troughing will deepen over the Midwest on Thursday and
shift east through the day. The associated cold front will extend
from Missouri into northeast Texas by the late afternoon hours.
With afternoon heating and moist southerly flow...showers and
thunderstorms will be on the increase over the area Thursday
afternoon into the evening hours. Instability and low level shear
will be on the increase across the area Thursday evening especially
in the Delta. The GFS/European model (ecmwf) indicate 35-40kt of 0-6km shear and ml
convective available potential energy of around 1000 j/kg by late Thursday evening in the Delta.
With the best combination of forcing/instability/shear being in the
Delta will continue to highlight these areas for severe potential
Thursday evening into the overnight hours in the severe weather potential statement and graphicasts.

The boundary will move into the northwest Delta during the early
overnight hours and will extend just east of the Mississippi River by
very early Friday morning and will continue to trek east through the
morning hours. The boundary will shift to the east of the area late
Friday morning along with the precipitation. Did not make any
changes to the forecast beyond Thursday will attach the
applicable portions of the previous long term discussion below. /15/

Long term...behind the front...expect much drier and cooler air to
move in bringing the first real taste of fall to the arklamiss this
weekend. The northern stream trough is looking stronger in the most
recent guidance and this is supporting cooler temperatures than
previously forecast. Highs should not rise above the middle 70s
Saturday under sunny skies and many locations could dip into the
middle/upper 40s Saturday night with surface high pressure and clear
skies overhead. These readings would be around 10 degrees below
daily climate normals. Some moderation of the airmass is expected
Sunday into Monday as the thermal through shifts eastward. /Ec/


Aviation...VFR conditions are expected to prevail this afternoon
into tonight as high pressure will remain over the area patchy
shallow fog will be possible across the region. As far as taf sites
are concern patchy fog may be an issue at mei and hbg by 10z
Tuesday. Also some stratus may come from the east around hbg. Expect
the stratus and fog to lift by around 14z. /17/


Preliminary point temps/pops...
Jackson 66 91 70 88 / 10 16 21 49
Meridian 60 91 67 89 / 10 5 15 46
Vicksburg 65 92 70 87 / 11 22 22 44
Hattiesburg 66 91 71 90 / 8 19 17 57
Natchez 68 89 71 89 / 9 28 26 56
Greenville 64 91 70 89 / 7 11 13 37
Greenwood 62 92 70 89 / 7 8 12 43


Jan watches/warnings/advisories...



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