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Area forecast discussion 
National Weather Service Jackson MS
345 PM CDT Friday Apr 18 2014


Late this afternoon through Saturday night...

Mostly light shower activity is focused with the middle level low center
in the general vicinity of Natchez...but this energy will consolidate
quickly with other energy over the Florida Panhandle region...bringing an end
to rain chances early this evening. A few showers will remain
possible over eastern MS closer to the middle level deformation zone.

Skies may clear for most of the area later tonight...and with afternoon
dewpoint/cross-over temperatures in the 50s and lows likely to fall
significantly below cross-over temperatures...fog may be a concern
late tonight into early Saturday morning. The risk is conditional on
relaxation of boundary layer winds and sufficient clearing. In the
wake of the middle level low...building middle level heights and surface
high pressure will bring dry weather to the arklamiss with seasonable
temperatures for the weekend. Thinking for the longer range forecast
is generally the same and no adjustments were necessary. /Ec/

Sunday through next Friday...

The tail end of Easter weekend still looks dry and warm but rain and
general tstorm chances will increase Monday afternoon and peak Tuesday morning
into the Tuesday afternoon as a weak boundary moves through. Temperatures
look to be near to just slightly above normal through the period.

Overall confidence remains above average with good model agreement
in the medium range while slightly decreasing at the end of the
period towards late next week with differing pattern progressiveness
depicted between ec/GFS/Gem. The arklamiss will be on the western
edge of a low amplified eastward progressing Omega block across the
southern Continental U.S. By Sunday evening. 700 mb-500 mb troughing will approach the
region by Monday morning while a weak surface trough Ushers a weak
boundary towards the region. Top-down moisturizing still appears to
be slow going Monday and have slowed timing just a bit more like
yesterday with slightly less shower/tstorm coverage Monday morning and
afternoon. Best coverage (scattered at best) will be across northern and
some central areas as precipitable waters climb towards 1.3" with 500-1000 j/kg
SBCAPE present. Instability will wane through the evening but enough
surface convergence from the weak boundary under moderate qg lift
should keep shower activity going through the overnight mainly
across the Highway 82 corridor. Weak boundary will push south through
the day Tuesday and with diabatic heating expected ahead...SBCAPE
values of 750-1500 j/kg should build and allow for regeneration of
general thunderstorms late morning Tuesday into the afternoon. Shear and overall
thermodynamics will limit potency of said thunderstorms to remain
sub-strong. Widespread heavy rain also does not appear to be a risk
and this will allow for swollen rivers to slowly abate. Will keep
severe weather potential statement clear for this slightly more active period.

For Wed-Fri...the weak boundary that settled near the coast will
return north by early Friday while a strong surface low and parent
trough develop across the central Continental U.S.. models are at odds on this
feature and this will be watched for any potential impact on the
arklamiss. This time frame will be warm with highs in the upper 70s
low 80s and limited rainfall potential until possibly next weekend.

&& abundance of MVFR category stratus will continue into
the early evening for sites in eastern MS...otherwise expect VFR
conditions to develop for most of the area later tonight. Some fog
and/or low stratus will be possible during the late night and early
morning hours. /28/ec/


Preliminary point temps/pops...
Jackson 52 76 52 81 / 5 1 5 4
Meridian 49 77 49 80 / 9 0 3 3
Vicksburg 51 77 51 81 / 5 2 5 4
Hattiesburg 50 78 52 82 / 11 3 2 4
Natchez 51 76 53 81 / 5 3 3 4
Greenville 53 77 53 81 / 5 2 6 11
Greenwood 52 77 52 81 / 5 2 5 4


Jan watches/warnings/advisories...