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fxus64 kjan 170215 aab 

Area forecast discussion...updated
National Weather Service Jackson MS
815 PM CST Sat Nov 16 2019


Updated for evening discussion.



Another cool, dry night is expected across the arklamiss region
tonight. Updated minimum temps for the morning to lower slightly
based on calm conditions. Some approaching cirrus from the west
may disrupt ideal radiational cooling at times, but feel most
locations should still hit freezing. Frost development looks
likely by the morning due to calm winds as well, so you may need
to break out the ice scraper if heading out early in the morning.
The rest of the forecast remains on track through tomorrow. /Nf/

Prior discussion below:

Tonight and sunday:

Continued dry and cooler than normal through the
period. Mid afternoon surface analysis had a 1025mb ridge axis
across our northwest zones nosing in from the northeast. Mid
afternoon satellite imagery/rap analysis had mid level shortwave
ridging just to our west. The surface ridge will remain in place and
weaken through Sunday while the shortwave ridge swings east across
the region and gets replaced by a deepening upper level trough by
Sunday evening. As a result, a decent night of radiational cooling
is expected again tonight with much of our area bottoming out around
freezing. There will be a few high clouds Sunday associated with the
approaching upper level trough but temperatures are expected to
recover to the lower 60s for much of the area. /22/

Tomorrow night through Saturday...

Dry weather with rebounding temperatures is expected through the
middle of the week before an unsettled pattern and increasing rain
chances return by late week. The forecast period starts off
tomorrow night with a trough axis rotating through the Mississippi
River valley with a closed cutoff upper low off the coast of Baja
California. A second impulse embedded within northwest flow aloft
is progged to dive through the region and into the base of the
longwave trough, but a lack of deep moisture in the column will
preclude any rain chances. Cooler air will advect through the
arklamiss on Monday keeping afternoon high temperatures in the mid
50s to low 60s. Heading into the middle of the week, broad
surface ridging is forecast to build in across the Gulf Coast
states beneath predominately zonal flow aloft. Warming 850mb
temperatures will support moderating afternoon highs with
temperatures climbing into the mid to upper 60s on Tuesday with
widespread upper 60s to low 70s Wednesday and Thursday.

By late next week, a series of upper impulses diving through the
Great Basin will help carve out a mean longwave trough over the
Desert Southwest. The aforementioned cutoff upper low over Baja
California will finally get picked up by the resulting southern
stream flow and is expected to become an open wave as it lifts
into the Central Plains. This synoptic pattern will allow for
southwesterly flow aloft to become centered over the Southern
Plains through the Mississippi River valley and into the Ohio
Valley. Increasing moisture return in concert with ejecting
shortwave troughs out of the mean Desert Southwest longwave trough
will support increasing rain chances Thursday through late week,
especially as a surface cold front drops into the area from the
northwest. Global guidance is in agreement on this general
pattern, but differ with regards to timing. The ecwmf is faster
with a frontal passage Thursday night into Friday morning while
the GFS is slower with the front sliding in during the day on
Friday. Will continue to keep rain chances in place, but will hold
off on increasing probabilities until there's better agreement as
to which period will see the best coverage. /Tw/



00z taf discussion:
VFR conditions and light winds are expected to prevail at all taf
sites through the period. A little patchy br cannot be entirely
ruled out in low-lying areas before 12z Sunday, but chances for
any impact on visibility at taf sites is too low to mention at
this time. /Nf/


Preliminary point temps/pops...
Jackson 32 63 36 59 / 0 0 0 0
Meridian 32 64 34 60 / 0 0 0 0
Vicksburg 32 62 38 61 / 0 0 0 0
Hattiesburg 33 64 36 63 / 0 0 0 0
Natchez 31 62 36 62 / 0 0 0 0
Greenville 32 57 38 57 / 0 0 0 0
Greenwood 31 60 36 55 / 0 0 0 0


Jan watches/warnings/advisories...


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