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Area forecast discussion 
National Weather Service Jackson MS
735 PM CST Monday Nov 30 2015


Made an adjustment to rain chances in the short term portion of
forecast to better fit areal probability of precipitation...and have added mention of
thunder to some locations based on current trends and steepening middle
level lapse rates noted in lzk/shv/Jan 00z radiosonde observations. Most recent
GFS/European model (ecmwf) guidance shows negative showalter indices and MUCAPES ~300
j/kg coinciding with current thunderstorms and rain translating east overnight across
northwest portion of the area then resetting over southeast half of the area Tuesday
afternoon as upstream shortwave energy noted in subtropical stream
enhances lift. /Ec/


Previous discussion... /issued 458 PM CST Monday Nov 30 2015/

Discussion...good warm air and moisture addition to
the clear skies allowed temperatures to climb into the upper 70s and
lower 80s across the south/southeastern portions of the area today.
Looking at observations from around the area it looks like the
boundary may have shifted slightly to the northwest. Dewpoints at
tvr were in the middle 60s...along with a few locations in northeast
Louisiana where values were in the upper 50s a few hours ago. Probability of precipitation
and temperatures will have a distinct gradient tonight...with the boundary
likely not moving much past the Natchez trace before midnight and
barely reaching the I-59 corridor by daybreak. Models continue show
moisture flowing into the region behind the boundary. Light rain
spreads across the entire area by Tuesday afternoon and continues into
late Wednesday. Looks like once temperatures fall into the middle 50s
they will be generally steady for a day or may be a little
dreary through middle week.

Went with the mav guidance in the short term and tried to show the
shift in the rain over the next 24-36 hours. With the system moving a
little slow...the southeast was able to get pretty warm today and
will likely be a little warmer than guidance tonight...and maybe
even early Tuesday. Generally went with guidance temperatures everywhere
except Meridian and Hattiesburg. Mav probability of precipitation were around 100 percent
for tonight through Tuesday...before tapering off. Opted to go with
the higher probability of precipitation and adjust the wording to reflect the intermittent
nature. Periods of rain seemed to fit well for tonight. Also fog was
already developing to the west/northwest and will be likely across
the area tonight once the rain spreads. Added patchy fog everywhere
northwest this evening and everywhere after midnight. Looks like low
stratus will be around also...but not confident in widespread dense
fog at this point. Leaned heavily on the hi res models for the
timing...but the NAM/GFS were in good agreement also. While the
movement of the boundary...will likely depend on how fast the ridge
builds from the west...for now it looks it will linger on Tuesday
and rain will continue. The northwest zones may be spared...but
systems typically do not move out as fast as the models
decided to hang on to rain in the northwest a little longer on

The ridge builds by Wednesday...pushing the low and and boundary
to the east finally by Wednesday afternoon/evening and keeps the
area dry for a couple days. May be a good weekend. A few
disturbances pass from Monday to Wednesday...but there does not
appear to be much rain. Air may be a little cooler and help keep
temperatures closer to normal. Models suggest a front and low
pressure system will move into the area late next Wednesday...bringing
back the rain. The surface low never seems to make it this far south
and quickly moves off to the northeast through OK/ may just be
some rain along the boundary with the system.

Aviation...most taf sites are seeing VFR ceilings this
afternoon as rain has been rather light and coverage sparse. The
exception to this as of 21z has been kglh which is encountering IFR
to LIFR conditions. Poor flying conditions will persist as a frontal
boundary remains stalled over the region. Ceilings will once again
drop to MVFR and IFR categories with the worst likely north of the
front. Khbg/kpib/kmei may encounter some patchy fog again Tuesday
morning but feel it may not be as dense but still will bring LIFR
ceilings and visible restrictions. Light rain will continue to plague
taf sites through tomorrow. /28/


Preliminary point temps/pops...
Jackson 54 59 46 57 / 91 90 86 43
Meridian 64 64 49 57 / 80 85 90 55
Vicksburg 52 57 45 58 / 92 81 68 31
Hattiesburg 65 71 54 60 / 49 71 85 55
Natchez 54 58 46 58 / 91 88 90 43
Greenville 51 56 39 57 / 90 25 22 12
Greenwood 51 56 40 58 / 95 57 28 21


Jan watches/warnings/advisories...



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