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fxus64 kjan 211135 aaa 
afdjan

Area forecast discussion...updated
National Weather Service Jackson MS
535 am CST sun Jan 21 2018

Update...
updated for 12z aviation discussion

&&

Aviation...
12z taf discussion:
as expected, some MVFR ceilings have begun working their way into
the Delta Region, namely kglh, this morning. These are expected to
linger through around 15-16z, before categories rebound to VFR
status heading into the afternoon. Winds will be breezy from the
south between 10-15 knots by late morning. This will especially be
the case in the Delta, where winds could gust up around 20 knots
during the afternoon hours. Ceilings areawide are expected to fall
to MVFR status overnight and into Monday morning, as low clouds
overspread the area and rain chances increase from west to east
ahead of an approaching cold front. /19/

&&

Discussion...
today and tonight...ridging aloft will continue to build through the
forecast area today, as an upper low and trough swings east into and
through the nation's mid-section overnight. At the surface, high
pressure remains wedged into the County Warning Area from the east through the
afternoon, but will begin shifting further east overnight in
response to an approaching cold front that'll be on our western
doorstep around day break Monday. The resulting pressure gradient
tightening over the forecast area will cause winds to be breezy from
the south today. Sustained winds will generally be between 10-15 mph
and gusting at times between 20-25 mph, especially across the Delta.

The increased warm advection over the region will also result in
continued warming over the forecast area. Under partly cloudy skies
this afternoon, look for highs to generally warm into the low and
middle 70s. Most of the forecast area will remain dry today, but a
few warm advection showers can't be ruled out, mainly over far
western portions of the County Warning Area.

Tonight, look for increasing clouds with lows ranging from the lower
50s to lower 60s. Rain chances will also steadily increase from
west to east, especially after midnight towards day break. Again,
with the front sitting on my western door step early Monday morning,
the better chances for showers and thunderstorms will primarily
reside west of the Interstate 20 corridor where a thin squall-
line will either be approaching my far western counties/parishes,
or just moving into them. /19/

Monday through Saturday...by Monday morning, a thin line of
showers and some thunderstorms will be on the doorstep of the
arklamiss, if not into the western portions of it. This line will
be in association with a closed upper low and surface low across
the Central Plains and an attendant cold front. At the beginning
of the period, this line should be weakening given the time of day
but as it progresses to the east there may be some slight
strengthening once again during the late morning through the
afternoon. Given MUCAPE around 500-1000 j/kg and ample shear(50kts
of deep layer shear and 30-40kts of low level shear), and some
intrusion of lower 60s dewpoints, this should be good enough to
bring some gusty winds to the region, especially in any part of
the line that can become strong to severe. Will likely put in a
marginal risk into the severe weather potential statement and graphics for at least a portion of
the area, most likely in the southern sections of the County Warning Area. This
line will progress quickly across the area and most of the rain
will be exiting the region by 18-21z. Highs on Monday will be in
the 60s and 70s areawide.

The region will remain dry following this front through the rest of
the week. Another shortwave trough will swing through the forecast
area by mid-week but should not bring any rain with it. The next
potential for rain and storms will come for the weekend. Showers
should increase across the area Friday night and continue through
the day Saturday ahead of a digging trough across the plains and a
developing surface low in the Piney Woods of East Texas.
Temperatures for the week will remain rather seasonal with highs in
the 50s, and eventually the 60s by the weekend. Overnight lows will
be in the 30s. /28/

&&

Preliminary point temps/pops...
Jackson 74 57 67 38 / 3 29 89 3
Meridian 73 51 69 38 / 2 14 78 8
Vicksburg 73 60 65 37 / 9 65 85 2
Hattiesburg 73 55 71 39 / 2 14 78 6
Natchez 73 61 66 38 / 15 63 88 2
Greenville 69 56 62 36 / 11 84 68 2
Greenwood 72 57 63 36 / 7 60 89 2

&&

Jan watches/warnings/advisories...
MS...none.
La...none.
Arkansas...none.

&&

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