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Area forecast discussion...updated 
National Weather Service Jackson MS
901 PM CDT Thursday Aug 28 2014

quiet night is in store is situated over the region. Precipitable waters slowly
have climbed on 00z kjan sounding to ~1.5 inches with deeper
moisture further S. Some middle/high clouds across the southern half of the
region will slowly move to the north/NE tonight...according to the hrrr.
These should not impact low temperatures overnight as they should be fairly
thin. Overall...lows look good across the region. Adjusted hourly
temperatures/dewpoints according to current trends. Rest of the forecast is
on track. /DC/


Aviation...convection over the south and west has dissipated and no
additional activity is expected until Friday afternoon. Middle and high level
debris clouds from the convection were noted on satellite imagery.
Similar to the last three evenings...these clouds will continue to
dissipate and VFR conditions will prevail areawide tonight. Fog
development has been light the last several nights and will only carry
mention of visibility restrictions at glh 10-12z Friday. VFR conds will prevail
most of the afternoon and evening Friday. Scattered coverage of storms is
expected Friday afternoon in the south with isolated coverage possible central and
west. Dry air will continue to limit activity in the NE. /22/


Previous discussion... /issued 357 PM CDT Thursday Aug 28 2014/

Short term...tonight through Saturday night...isolated to scattered
afternoon showers have developed and will continue to affect the
region through this afternoon and potentially into early evening.
Morning microburst analysis indicated poor instability and lapse
rates so these should just produce some brief heavy rain and maybe
some lightning(most of these are not showing lightning). These will
dissipate this evening with the loss of daytime heating. The rest of
this evening will be quiet.

The region is situated between ridging to the east over the coastal
states and a trough across the plains. Through the course of Friday
and especially into Saturday...moisture will return in full force to
the region. Precipitable water values by Saturday will be reaching 2
inches...especially across western areas. While the region will see
some storms on Friday afternoon...the biggest concern for storms and
heavy rain will be on Saturday. This will come as the upper trough
swings into the area but also models show a more subtle disturbance
embedded in this moisture plume that should enhance widespread precipitation.
With precipitable water values exceeding 2-2.2 inches on Saturday...heavy rainfall
will be a concern with 2-4 inches possible and locally higher
amounts...especially in the west where moisture transport will be
higher and have added this location as a limited risk in the severe weather potential statement and
graphics. In terms of severe isnt completely out of the
realm of possibility as shear values are not too bad but instability
is questionable. Will hold off on any mention right now but may need
to be added in later forecasts. In terms of temperatures...highs will
be held in check thanks to precipitation and abundant cloud cover over the
region. I actually cut temperatures in the west and northwest a
little based on this expectation. /28/

Long term...Sunday through Thursday...for the work week...the pattern will
adjust and more middle/upper level ridging will take shape over the
region. This will help to taper precipitation chances back to more of a
20-30% variety with timing more diurnally driven. Temperatures will warm and
make a run into more of the Lower/Middle 90s. /Cme/

Preliminary point temps/pops...
Jackson 71 95 73 89 / 7 14 36 68
Meridian 66 95 72 90 / 6 7 35 59
Vicksburg 70 95 73 86 / 9 18 36 69
Hattiesburg 71 95 75 90 / 6 41 36 62
Natchez 71 93 73 85 / 8 35 38 69
Greenville 71 95 72 84 / 5 17 32 69
Greenwood 68 96 73 85 / 4 12 33 69


Jan watches/warnings/advisories...


District of Columbia/22/28/cme

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