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Area forecast discussion 
National Weather Service Jackson MS
400 PM CDT Wednesday Aug 27 2014

Discussion...temperatures will continue to be a little hotter than
average over the next few days as high pressure ridging aloft over
the lower MS valley remains the dominant influence over our weather.
Tropical moisture and a few weak disturbances in the Gulf of Mexico
will have their influence confined close to the coast through
tomorrow...with therefore any isolated afternoon and evening showers
and storms mainly limited to my far southern zones in that time
frame. Gradually increasing moisture will raise low temperature
expectations tonight and humidity a little tomorrow...but through
Friday we still expect peak heat index values to generally remain
shy of the century mark.

By later Friday model consensus is confident that an incoming and
non-trivial upper trough approaching from the plains will help break
down high pressure in our vicinity and push the center of the ridge
to our east. Late Friday afternoon into Friday night southerly flow
into our region in the atmospheric lower levels will increase and
begin importing deep Gulf moisture inland. Still thinking most of
the afternoon and evening showers and storms will remain confined
south of I-20 into Friday evening but those trends will be monitored
closely due to relative importance Friday evening activities around
the region. The previous idea of most of the precipitation holding
off until Saturday remains quite valid and locally heavy rain could
be an issue going through Saturday night and into early Sunday.
Trends on this will continue to be monitored with regard to possible
mention in the severe weather potential statement. /Bb/


Previous discussion... /issued 404 am CDT Wednesday Aug 27 2014/

Discussion...Friday through early next week...medium range models
continue to be in decent agreement on the pattern evolution through
the extended period. Initially and over the weekend...the GFS/Euro
both agree on our region being on the southern end of a trough that
will move through the central sections of the Continental U.S.. this trough
will increase the S/SW flow through a deep layer and help draw
northward rich tropical type moisture (pws 2.1 to 2.4 in).
Additionally...each model indicates a more subtle shortwave feature
embedded in this deep moisture plume which helps in the generation
of more widespread type precipitation activity for Sat-Sat night. Low level
moisture transport and propagation vectors indicate the potential
for locally heavy rainfall...especially Sat night. This will have to
be watched for flooding potential over the next few model cycles. As
for temperatures during the Friday-sun period...look for Friday to be the warmest
with highs 90-94 degrees. High temperatures over the weekend will be held
in check by thicker cloud cover and precipitation...85-90 will be a more
common range for Sat-sun. As for lows...look for each day to run on
abnormally the warm side with lows 72-75.

The best chances for precipitation will be focused between Sat-sun. Once we
get into next week...the pattern will adjust and more middle/upper
level ridging will take shape over the region (se conus). This will
help to taper precipitation chances back to more of a slight chance variety
while allowing for temperatures to make a run into more of the Lower/Middle
90s. /Cme/


Aviation...prevailing VFR conditions expected through Thursday.
Hbg/pib will have some chance for getting afternoon rain showers/thunderstorms and rain
activity though it currently looks to remain south of there. All
other locations should remain dry. Could be some brief MVFR
conditions in the predawn hours before resuming VFR. /28/


Preliminary point temps/pops...
Jackson 67 94 71 95 / 5 6 11 19
Meridian 63 95 68 94 / 4 4 9 16
Vicksburg 66 94 70 93 / 6 11 16 21
Hattiesburg 70 95 72 93 / 12 12 8 35
Natchez 69 92 71 92 / 15 23 15 22
Greenville 68 95 72 93 / 4 3 13 25
Greenwood 65 95 70 94 / 3 2 10 19


Jan watches/warnings/advisories...



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