807
FXUS64 KJAN 060304
AFDJAN

Area Forecast Discussion
National Weather Service Jackson MS
1004 PM CDT Sun May 5 2024

...New MESOSCALE UPDATE...

.MESOSCALE UPDATE...
Issued at 1004 PM CDT Sun May 5 2024

Rest of tonight...

GOES East water vapor imagery indicate spoke of shortwave trough
axis ejecting out of the ArkLaTex into the ArkLaMiss region, west
of the MS River. Broad ascent, with a MCV, continues out ahead,
providing the impetus for some convective initiation of isolated-
scattered storms in the Hwy 82 corridor. Expect this to lift
northeast the few hours & dissipate around midnight at the latest.
MLCAPE around 1000-1500 J/kg & mean bulk shear around 30kts in
the 0-3km & 0-6km layer, a few robust storms have developed in
this zone. A few additional strong storms are possible & can`t
rule out an isolated severe storm before it moves out of the area.
Southwesterly flow will persist but weaken as the shortwave
ejects across the Mid MS Valley overnight. HREF probs are much
less & confined to the extreme Hwy 98 corridor & Pine Belt but fog
can`t be ruled out. Moist southerly flow will keep seasonably
warm lows in the mid-upper 60s & another round of patchy fog
southeast of the Natchez Trace corridor. Probs are too low to
introduce any potential for patchy dense fog, but most probable
area of localized dense fog concerns would be in the extreme
southeast. Updates are out. /DC/

&&

.MESOSCALE UPDATE...
Issued at 730 PM CDT Sun May 5 2024

Rest of this evening...

Main updates to the going forecast were to cut PoPs around 30% or
so areawide through midnight as coverage is sparse & any
development is late & driven by weak forcing. In addition, fog
formation looks possible overnight in the Pine Belt, so this was
added as well. Later fcst update will focus more on this. Updates
are out. /DC/

&&

.DISCUSSION...
Issued at 311 PM CDT Sun May 5 2024

Tonight through Monday...

A short wave is kicking off scattered showers/storms across the
area this afternoon and this will continue into the evening hours.
A marginal risk continues, with the main risk being damaging wind
gust and hail. The storms will weaken and move north out of the
area through the evening hours, ending by late evening. Expect
partly to mostly cloudy skies overnight, with some patchy fog
possible across the Pine Belt Region. Lows tonight will be in the
mid 60s. Weak upper ridging and drier air will build across the
area on Monday, but there will continue to be isolated to
scattered diurnal storms Monday afternoon. Highs will climb into
the mid/upper 80s across the area. /15/

Tuesday through Sunday:

The pattern through at least Thursday will continue to support
chances for convection in our region. An upper-level low pressure
system wobbling over the Northern High Plains through the midweek
looks to shear out with a portion absorbed in the westerlies over
the Great Lakes Thursday into Friday and a portion cutting off from
the remaining trough over the Great Basin. Above normal heights with
a flat ridge retreat toward the southern Gulf of Mexico during this
time frame. This pattern should allow for a period of decent
westerly flow aloft over our forecast area (75+kts) with the
southern jet stream and resulting 30-50 kts of 0-6km shear through
Thursday. Disturbances in the flow aloft will interact with a hot
and humid air mass at the surface, with daytime heating leading to
over 2000 J/kg of MLCAPE daily. This is a favorable parameter space
for strong to severe thunderstorms around the region, especially if
disturbances are timed out to pass overhead during peak heating. A
Marginal Risk for severe thunderstorms currently exists for Tuesday
afternoon in Arkansas and northern Mississippi, increasing to Slight
Risk for severe thunderstorms by Wednesday for much of the same
area. Flow becomes more boundary-parallel to a front dipping into
the region on Thursday, but favorable parameters indicate the threat
for severe weather will continue into Thursday as well - likely for
areas a little farther south around the Interstate 20 corridor or
closer to the Gulf Coast.

Additionally the westerly flow, increased wind shear, and high
moisture content to the air should lead to efficient rain producing
storms. Localized flash flooding will be a concern at times. For now
will continue to combine theses threats on a mid-week storms graphic
to highlight a period of possible severe weather and flooding
concerns. Details will come into better focus for the respective
threats as preceding events play out.  The afternoon highs before
this front will likely reach the lower 90s for portions of the are
through Thursday. A turnaround to cooler-than-normal temperatures
with building high pressure after the front will bring relief for
the weekend. /NF/

&&

.AVIATION...
(00Z TAFS)
Issued at 736 PM CDT Sun May 5 2024

Other than a brief period of SHRA & iso TSRA activity, most will
begin to wind down over the next few hours, with majority gone
around midnight. VFR conditions prevail across the area this
evening. Some MVFR vsby due to BR are psbl around the area, with
IFR-LIFR low stratus/BR expected overnight at HBG, PIB & MEI.
Onset timing looks to be around 06/07-10Z before lifting to VFR
flight categories around 05/14-15Z while closer to06/17Z at HBG &
PIB. Light southerly sfc winds will persist, sustained up to
10-15mph & brief higher gusts up to 20mph. Some light SHRA & iso
TSRA are psbl again Monday aftn. Confidence isn`t high enough to
introduce in the 00Z TAF cycle. /DC/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       67  87  70  87 /  20  40  10  40
Meridian      66  88  68  89 /  20  30  10  40
Vicksburg     67  86  70  88 /  30  30  10  20
Hattiesburg   68  88  70  89 /  10  30   0  30
Natchez       66  86  69  88 /  10  40  10  20
Greenville    68  85  71  86 /  40  30  20  30
Greenwood     67  85  71  86 /  50  30  20  40

&&

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

$$

DC/NF/DC