Byram, Mississippi 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

282
FXUS64 KJAN 130526 AAC
AFDJAN

Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
1126 PM CST Tue Nov 12 2024

...New AVIATION...

.MESOSCALE UPDATE...
Issued at 928 PM CST Tue Nov 12 2024

Big picture view is that no major changes are needed from earlier
evening update to expand POPs coverage into the daytime hours
tomorrow. Taking a closer look at near-term trends, have increased
POPs in the Pine Belt areas overnight where at least light rain or
sprinkles are possible into daybreak time frame. Then as low-level
warm, moist advection continues - and as lift associated with
approaching upper-level trough increases - the potential for rain
will increase north and west into the ArkLaMiss Delta regions
early tomorrow. Based on expected coverage and synoptic scale
support for rain, POPs were boosted higher than NBM guidance into
the 80-90 percent range before Noon tomorrow for northeast LA,
far southeast AR, and our northwest MS counties. Then surface low
pressure disturbance over the northern Gulf will lift into our
area heading into the afternoon. In addition to the increasing
deep layer shear with the upper-level trough, this low-level
disturbance will both destabilize lower levels with moisture
advection and increase low-level wind shear and helicity values
east of the approaching cold front. Projected MLCAPE values are
fairly modest due to cloud cover, but a few hundred J/kg should
support some surface based convection spreading northward. Shear
and instability by Noon should support the current advertised
Marginal Risk for severe thunderstorms focused mainly south of a
Bastrop to Yazoo City to Meridian across our forecast area.
Isolated damaging wind gusts are the primary threat, but some
tornadoes cannot be ruled out as well. Storms could produce heavy
rainfall especially by later in the day, so the Limited threat for
flash flooding will continue to be highlighted in local graphics.
/NF/

&&

.DISCUSSION...
Issued at 254 PM CST Tue Nov 12 2024

Tonight and Wednesday:

Ridging surface and aloft that was so prominent over our CWA
early this morning will continue shifting east tonight allowing an
inverted trough to increase moisture back across the CWA. This
inverted trough was just off the coast of southeast Louisiana at
mid afternoon and will continue moving west northwest tonight into
Wednesday morning. Deep moisture will continue to increase over
our CWA Wednesday morning ahead of a rather amplified shortwave
trough and cold front that will be approaching our CWA. Although
lapse rates and overall instability look to remain limited, PWs
will be back between an inch and three quarters and two inches by
noon Wednesday which is well above normal. As the low pressure
system draws closer to our CWA, wind profiles will be such that
isolated severe storms capable of producing a brief tornado or two
will be possible. In addition, brief heavy rainfall of a couple
inches in a short amount of time will likely lead to runoff issues
and possible flash flooding. The main time of the severe threat
and flash flood threat will be mid afternoon through Wednesday
evening but a few storms may get an earlier start in our west.
Temperatures will continue to be warmer than normal. /22/

Wednesday night through next Tuesday:

By Wednesday night into Thursday, an upper trough will continue move
east across the Lower Mississippi Valley and push a cold frontal
boundary into the region overnight. Rain chances will diminish from
the west by Thursday morning. In the wake of the frontal boundary,
drier air is expected to infiltrate the region, with northerly flow
expected to prevail over CWA for the next several days. PWATs are
expected to drop below an inch, allowing for mostly clear skies
through the end of the week. Additionally, temperatures are expected
to become more seasonable, with highs in the middle 60s to low 70s
and overnight lows in the lower to upper 40s through the weekend.

By Saturday night into Sunday, a subtropical high is expected to
build in the Gulf of Mexico, allowing for robust upper ridging over
the eastern CONUS. This is expected to increase temperatures once
again by Monday. Additionally, moisture will begin to increase as
southerly flow is restored across the Lower MS Valley. By next week,
abnormally warm temperatures will infiltrate the region, with highs
in the middle to upper 70s. By Monday night, another upper low
pressure ejecting out Southern Plains will increase rain chances
across the region and isolated to scattered showers will prevail on
Tuesday. /AJ/

&&

.AVIATION...
(06Z TAFS)
Issued at 1125 PM CST Tue Nov 12 2024

Increasing coverage of low stratus and light rain will lower
conditions to MVFR and then IFR through 12Z at most sites. Rain
will become more showery, with heavier showers possible mainly
after 15Z as a cold front moves east into the forecast area.
Ceilings and visibility are likely to be variable with showers and
isolated storms, but prevailing conditions through much of the
afternoon will favor IFR ceilings to the west and MVFR ceilings
to the east, with periods of reduced visibility with heavier rain.
Rain and ceilings will begin to clear from west to east in the
wake of the cold front passage late in the period. /NF/


&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       65  76  57  69 /  50  90  80  10
Meridian      64  73  60  71 /  30  80  90  10
Vicksburg     64  75  54  69 /  60  90  40   0
Hattiesburg   66  78  63  75 /  40  80  70  10
Natchez       66  76  56  69 /  50  90  40   0
Greenville    60  72  50  66 /  50  90  30   0
Greenwood     62  74  53  68 /  60 100  60   0

&&

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

$$

22/AJ/NF