Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Jackson MS
237 PM CDT Thursday Sep 18 2014

Short term...upper troughing prevails across the arklamiss this
afternoon with an associated frontal boundary extending across the
northern portion of the area. A short wave is moving into the Delta
and this combined with the boundary is the focus of some afternoon
thunderstorm development. With increased stability and flow aloft
some of these storms have become strong to severe. Expect the storms
to persist into the evening hours...especially near the boundary...
but most of the hi-res models suggest that they should dissipate
before midnight. The short wave will shift to the south of the area
overnight and this will push the boundary just south of the area
also...bringing in some drier air across the area by Friday morning.

Weak upper ridging will begin to build across the area on Friday and
this combined with the drier air will make for a nice day under
partly cloudy skies. Upper and surface ridging will strengthen
across the area on Saturday and the result will be mainly partly
cloudy skies and highs around 90 degrees. Surface high pressure will
continue over the area Saturday night into Sunday with lows in the
low to middle 60s. Did not make any changes to the forecast past
Saturday will attach the applicable portions of the
previous long term discussion below./15/

Previous long Sunday, a ribbon of 1.5-1.6" precipitable waters will
pivot into northwest/west areas ahead of a front aided by stronger northwest flow as
eastern Continental U.S. Trough amplifies south in conjunction with strong
surface high in Central Plains. This environment could support a few
weakly instability induced showers.

The new ec is more bullish (and more in line with gfs) then previous
run on stronger southward frontal momentum through region late
Monday into Tuesday morning. As front moves through Monday, moisture
looks to be lacking and weak low-level convergence will also be in
play. Yet, feel showers and a rumble of thunder will have a chance
to develop as boundary moves through. Best concentration of rain
with current thinking of timing will be along and south of I-20
where instability will be greater Monday afternoon. At least lower 50f
dewpoints look to infiltrate through most of region by midday
Tuesday along with some cold air advection in the 925/850mb layers. These
components will allow for temperatures to fall back towards normals
in the upper 50s/low 60s and highs in the middle 80s Tuesday with
slight moderation Wednesday as front may waffle back north along far
south areas. /Allen/


Aviation...Fr conds will prevail at most taf sites through this
afternoon...other than brief MVFR/IFR due to thunderstorms and rain. Showers/storms
are currently near kglh/kgwo between 18/19-00z and will move near
kjan/khks at 18/22-01z. Expect some brief MVFR conds tonight at
kmei/khbg between 19/08-14z and kglh/kgwo between 19/10-14z before
clearing after 19/15z. /DC/


Preliminary point temps/pops...
Jackson 90 67 91 66 / 40 20 1 1
Meridian 90 64 92 64 / 31 15 1 1
Vicksburg 90 65 91 64 / 43 16 2 1
Hattiesburg 92 68 92 68 / 42 34 8 4
Natchez 88 67 89 67 / 48 33 7 4
Greenville 88 67 90 67 / 50 25 1 1
Greenwood 88 66 91 66 / 50 29 1 1


Jan watches/warnings/advisories...


15/District of Columbia

National Weather Service Glossary of Abbreviations