National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXUS64 KJAN 200922
AFDJAN

Area Forecast Discussion
National Weather Service Jackson MS
422 AM CDT Sat Apr 20 2024

...New DISCUSSION...

.DISCUSSION...
Issued at 421 AM CDT Sat Apr 20 2024


Today and Tonight:

A stationary frontal boundary currently resides along a northeast
to southwest line stretching from just south of Meridian, to near
Brookhaven, to just south of both Concordia and Catahoula
Parishes on Louisiana. Behind this front, northerly winds will
allow for cooler drier air to filter south into the CWA, while
moisture pools ahead of it under southerly surface winds. For
today, a mid/upper level disturbance embedded in zonal flow aloft
will traverse the region along this boundary. This`ll result in
widespread showers and scattered thunderstorms developing across
the forecast area through the day. There will be a lull in
activity this evening as the first disturbance exits the region.
However, another disturbance will again track east across the
region late tonight in early Sunday morning. This will yet again
bring widespread showers to the forecast area, as the cold front
finally pushes southeast and out of the CWA.

Although cold advection is occurring in the wake of this boundary,
the process is currently quite slow.  With precipitable H2O values
across much of the CWA progged between 1.50-1.75 inches and
convection forecast to move west to east across the CWA, heavy
downpours can be expected with today`s activity, and again with
tonight`s as the front pushes out of the area.  As a result, a
limited threat for flash flooding exists today into tonight. This
will particularly be the case over areas mainly along and north of
the Interstate 20 corridor where widespread heavy rainfall fell late
last week, & again during the middle of this week, & as today and
tonight`s convection is progged to train across the same locations.
Here, 1-3 inches of rain will be possible. This could result in
further flash flooding of low-lying and poor drainages areas, as
well as further contribute to ongoing river flooding in the area.

In addition to this limited flash flooding threat, a "Marginal Risk"
for isolated severe storms will exist across the Pine Belt region
this afternoon and early evening.  Here, the better combination of
instability, wind shear, and steep mid-level lapse rates will exist.
As a result, isolated severe storms capable of producing damaging
wind gusts and hail up to the size of quarters will be possible from
around 1 PM today through 7 PM this evening.

As far as temperatures are concerned through the period, a decent
spread of temperatures is expected from north to south across the
CWA due to the aforementioned stalled frontal boundary.  Look for
highs to range from around 60 across the Delta region, to around 80
across the Pine Belt.  Then for tonight, lows will range from the
middle 40s north to middle 50s south. /19/

Sunday through Friday:

The chance for rain will continue into the afternoon Sunday,
clearing from north to south as an upper-level shortwave trough axis
clears the region and drier surface air works into the region with
high pressure. Overnight lows have a chance to radiate a little
cooler with the surface high sliding overhead Sunday night and
Monday night, but at this time think even the cooler locations
should remain too warm for frost. That said, a brief touch of frost
cannot entirely be ruled out in those typically cold drainage
locations in northern Mississippi either night. Otherwise, the rest
of the forecast period will see a warming trend as an upper-level
ridge steadily builds and shifts eastward toward the Mississippi
River Valley by late week. Models begin to diverge with regard to
timing of a shortwave ejecting from the Southwest U.S. later in the
week, but a glancing blow from the wave could bring a chance for
showers and thunderstorms to at least northwestern parts of our
forecast area by the end of the week. /NF/

&&

.AVIATION...
(06Z TAFS)
Issued at 1221 AM CDT Sat Apr 20 2024

A mix of MVFR/IFR flight categories will be observed at area TAF
sites through this 06Z forecast period. This will be as a result
of low stratus increasing across the area through the overnight
hours. Then toward day break and continuing throughout the day,
scattered to numerous showers and isolated to scattered
thunderstorms will plague the area as a disturbance moves west to
east across the region where a stationary frontal boundary
resides. Sites ahead of the front will observe calm to light
southerly winds overnight, while winds will be from the north
between 5-8 knots in the wake of it. /19/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       69  49  62  42 /  80  90  60   0
Meridian      71  47  62  42 /  70  90  70   0
Vicksburg     65  49  63  42 /  70  90  50   0
Hattiesburg   80  53  62  45 /  60  70  60   0
Natchez       71  49  62  43 /  60  90  50   0
Greenville    59  50  62  43 /  80  90  20   0
Greenwood     62  48  63  42 /  70  90  30   0

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...None.
LA...None.
AR...None.
&&

$$

19/06