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Area forecast discussion...updated 
National Weather Service Jackson MS
921 PM CDT Friday Aug 22 2014

skies are all clear tonight. The hourly temperatures were updated so to
match the current trend. Otherwise the forecast is good. Quiet
conditions anticipated to continue. /10/


with the exception of a brief period of MVFR for visibilities in fog
at mei and hbg between 10 and 13z...VFR conditions will prevail
through the period./26/


Previous discussion... /issued 355 PM CDT Friday Aug 22 2014/

Short term...convection is thus far struggling in south
Mississippi...probably because today there is widespread weak
subsidence aloft across the region due to the ridge of high pressure
in place. There is still some potential that isolated showers in
southeastern zones will flair up and produce a few storms with a bit
of gusty winds and lots of lightning before activity disappears
entirely by 7 or 8 PM. Otherwise anticipate hot and muggy conditions
only gradually cooling off this evening...which of course is not
nearly quick enough to keep participants and viewers of early
evening local sporting events from breaking a good sweat.

Highs this afternoon will range from 94 to 98 degrees...but
anticipate the heat to build further over the weekend as the upper
ridge reaches the peak of its subsident influence. Thus...maximum
temperatures for Saturday and Sunday will likely be a degree or two warmer
than this with a few spots reaching the century mark (in terms of
raw temperatures) not at all out of the question. Conditions will
certainly be muggy...especially in the morning hours and in the
evening. However...moisture levels should not be quite high enough
to keep lows above 75 degrees at night and to prevent relative
humidity from decreasing a lot in the afternoon. For these reasons
we will continue to forgo application of a heat advisory to any part
of the forecast area...instead covering peak heat indices in the 104
to 108 degree range through at least Sunday with an elevated
dangerous heat threat in the hazardous weather outlook and graphics.

Other than the heat this weekend we will have to watch out for later
afternoon and evening showers and storms coming into eastern zones
from out of the Alabama on Sunday. Saturday poses relatively little
threat of convective activity but any storms Sunday should be strong
with lots of lightning and brief gusty winds. Future shifts will
have to monitor potential for severe weather late Sunday because the
recent trend of an incoming west-bound inverted trough combining
with excessive heat and moisture is a recipe for potent convection
if our confidence can increase on the fact that storms will actually

Confidence is higher that this westward-moving low level inverted
trough feature will trigger scattered showers and storms over many
areas of the region on Monday afternoon...and probability of precipitation were increased
for that period with this package. This could also tend to confine
major heat to western zones on Monday since elsewhere convection
would probably start early enough to limit maximum temperatures a good in
comparison to this weekend. /Bb/

Long we go into next week moisture will build across the
region from the east. This will give the region a break from
extremely hot afternoon high temperatures. Rain chances will pick up
as deep tropical moisture builds across the region. Precipitable waters will
increase to around 2.2 inches before fluctuating around 1.5 to 1.9
inches for Wednesday into Thursday. There will be decent instability
for some convective chances from Monday through Thursday with some
locally heavy rainfall potential. The mean ridging will fluctuate
some during the upcoming work week.

As far as model differences are concerned most of the ensembles...
Euro...Navy and UK models keep the mean ridge dominant over our
region. The GFS once again tried to bring an upper trough over the
region by the middle of next week. Thus it will try to push a front
into the region toward the weekend...which seems to be an outlier.
Models were in general agreement with the weekend heat and increase
in tropical moisture from the east for next week. The 6 to 10 day
outlook calls for above normal temperatures and rainfall going toward

Otherwise...we will have to keep an eye on the tropics as we move
toward the typical peak in activity associated with the hurricane
season. There is currently an large tropical wave near Hispaniola
which is tracking westward and has high potential for development
over the next 3 to 5 days. A majority of computer models recurve any
developing system back out into the Atlantic although it is still
not impossible that at least some of this tropical energy might
circuitously finds it way into the Gulf later next week. We will of
course keep you updated and check www.NHC.NOAA.Gov for all official
updates and tropical advisories. /Bb/17/


Preliminary point temps/pops...
Jackson 73 98 73 99 / 0 7 5 8
Meridian 71 99 71 99 / 0 8 7 16
Vicksburg 71 97 71 98 / 0 6 5 7
Hattiesburg 75 98 75 99 / 0 14 13 11
Natchez 73 95 73 96 / 0 11 9 5
Greenville 72 98 73 99 / 0 5 4 8
Greenwood 71 98 72 98 / 0 5 4 12


Jan watches/warnings/advisories...


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