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Area forecast discussion 
National Weather Service Jackson MS
340 PM CDT Thursday Aug 27 2015

Discussion...benign and mostly dry weather conditions are expected
to continue over the next few days as a relatively dry airmass
remains over the area. A surface high currently centered over the
northeast will gradually begin to lose grip as a weak upper low
begins to cut off along the central Gulf Coast tomorrow into early
Saturday. By Saturday, weak low level return flow will help erode an
air mass currently characterized by precipitable water less than an inch and middle
level dewpoint depressions over 30c. By Saturday and Sunday isolated
afternoon convection will be possible across mainly the eastern
portion of MS, as precipitable water recovers to around 1.5 in from the east, but
most of the area is expected to remain dry these days.

As for fire weather concerns, dewpoints didn't decrease as
significantly through today as in previous days. There are still a
few areas showing relative humidity less than 30 percent, but a trend toward
somewhat greater humidity should continue into Friday. Wind has also
been less gusty through the day. We will maintain the current limited
fire threat, but not extend into tomorrow at this point.

Erika remains a weak tropical storm over the northeast Caribbean Sea.
After somewhat of a lull in convection around the center this
morning, new development has occurred this afternoon. As the storm
remains relatively weak right now and will encounter increasing
shear and then land over the next 24 hours, there is great deal of
uncertainty with regard to how well the storm will survive during
this time period. Beyond this, assuming the system holds together,
the consensus forecast still keeps Erika east of our area with the
help of a weak middle/upper trough that is expected to remain
positioned from the middle MS valley southward to the northwest Gulf. /Dl/

The remainder of the previous long term discussion follows...

Global models forecast the upper level trough responsible for the
recent dry and mild weather to lose definition and weaken...but
still remain a fixture over the lower MS valley region as we go
through the weekend and early next week. Weak southerly low level
flow will develop and increase moisture transport over mainly
southern and eastern eastern MS resulting in slightly greater
potential for diurnal convective rainfall. The late August sun will
ensure that heat and humidity will be on the increase as well. The
most noticeable changes will be warmer and muggier conditions at
night...and afternoon heat indices reaching the upper 90s Tuesday/
Wednesday. /Ec/


Aviation...VFR conditions will prevail throughout the forecast
period. North northeasterly winds will subside to light to calm
this evening...and remain so into early Friday morning. /19/


Preliminary point temps/pops...
Jackson 63 92 66 92 / 0 0 3 6
Meridian 63 91 66 90 / 0 4 4 16
Vicksburg 60 91 62 93 / 0 0 0 6
Hattiesburg 63 92 67 91 / 0 4 4 9
Natchez 62 89 64 91 / 0 0 0 5
Greenville 61 90 65 92 / 0 0 0 7
Greenwood 61 90 65 93 / 0 0 1 7


Jan watches/warnings/advisories...



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