761
FXUS64 KJAN 170716 AAC
AFDJAN

Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
216 AM CDT Fri May 17 2024

...New AVIATION...

.MESOSCALE UPDATE...
Issued at 946 PM CDT Thu May 16 2024

The severe storm threat and locally heavy rain threat has ended
for the night. Regional radars showed and MCS moving east across
southern Louisiana and the coastal waters. This activity will
track south of our CWA so a large area of light to moderate rain
will continue spreading northeast across the remainder of our CWA
the remainder of the night. Thunderstorm activity within the
large area of rain will remain confined to the southern half of
the CWA. Models suggest another subtle shortwave will help develop
more vigorous convection toward morning over our western zones
that will prolong rain chances over the eastern half of the area
Saturday morning. /22/

&&

.DISCUSSION...
Issued at 309 PM CDT Thu May 16 2024

Tonight and Tomorrow: The southern jet continues to increase as
the positively tilted through axis remains over the southern
Plains. The trough axis will continue to send shortwave energy
east across northern Texas and into our area. As the winds shift
southwesterly low level-moisture will increase by lifting the warm
front north this evening. Shortwave energy interacting with the
increased low-level moisture will be the main source of forcing to
increase showers and storms from west to east through Friday
evening. With PWAT values increasing to near 2.0in and low level
jet increasing we can expect heavy rainfall and likely flash
flooding. As the upper level flow become divergent across central
MS guidance has evolved to show the highest band of rain closer to
the coast. Areas along and south of I- 20, 2-4in of rain is
likely, especially in the Pine Belt, where locally higher amounts
are possible, throughout the event. With the primary threat being
the heavy rainfall and flash flooding with high rainfall totals
through Saturday afternoon, the Flash Flood Watch will take
effect from 6Z Friday-16Z Saturday. However the Watch has been
trimmed down on the western edge from Franklin parish to Hinds
county to reflect the highest probabilities to the east.
Convection will be stratiform in nature as remnant storm activity
over north Texas will spread east/southeast into the more
unstable air along the southern half of our CWA. In addition, it`s
worth noting with the sfc low being W/NW of the area and
convection being stratiform that there are indications in the CAMs
that a wake low could form behind the the stratiform rain
tonight. Potential wind gusts of 30-40 Kts will be possible along
and south of I-20 around midnight if confidence increases. As the
warm front lifts along the coast tonight storm propagations will
make a shift as they move N/NE going into the early morning hours.
This latter development will be the main driver of the marginal
risk for severe weather as redevelopment along the outflow of
previous storms have an increased threat for damaging winds and
tornadoes cant be ruled out. The Marginal Risk for tonight and
Slight and Marginal Risk for tomorrow have been trimmed from
the north and expanded east along the southern portions of the
CWA through Saturday morning./KP/

Friday night through mid next week (Wednesday): Weekend
(Saturday- Sunday): Cold core low that will have been bringing the
heavy rain & severe potential across the region will moving
across the ArkLaTex into the Gulf coast region by the weekend.
This will bring a gradual end to the convection, but some heavy
rainfall totals will be ongoing at the start across the Pine Belt
into the Hwy 98 to I-59 corridors, where an additional 2-3 inches
is possible. The ongoing Flood Watch remains in effect, but has
been oriented more southwest to northeast to account for this
activity. "Elevated" in HWO graphics has been adjusted
accordingly. Some severe activity may be ongoing but probably
finished into late Saturday evening. Upper low will swing into the
Appalachians, with ridging at the sfc & aloft building in from
west-east. This will drive in drier air late Saturday aftn &
persisting through the weekend. Expect moderation of highs in the
low-mid 80s Saturday & mid-upper 80s Sunday, with increasing
potential heat & humidity late weekend.

Next week (Monday-Wednesday): As the mid-level & sfc ridge builds
in, increased warm advection will bring up low-level temps into the
upper teens to low 20s degree C at 850-925mb layers. Expect highs to
moderate to seasonably warm into the low 90s & lows in the upper 60s
to low 70s northwest of the Natchez Trace. Heat & humidity will be
on the rise around midweek with heat indices climbing into mid-upper
90s. Low-level return flow won`t pick back up until by midday
Tuesday through midweek, with rain & storm chances picking back up
around mid-late week. /DC/

&&

.AVIATION...
(06Z TAFS)
Issued at 208 AM CDT Fri May 17 2024

Rain and the chance for some TSRA will be the primary challenges
to the forecast for flying through at least 15Z. More confidence
exists for lowering ceilings in the near-term though. Widespread
MVFR to IFR ceilings are expected to develop by 10Z and prevail
through around 15Z to 18Z. /NF/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       67  82  65  86 /  50  50  10   0
Meridian      66  83  64  89 /  60  70  20  10
Vicksburg     67  84  65  89 /  40  30  10   0
Hattiesburg   68  84  66  89 /  60  70  10   0
Natchez       67  84  65  88 /  50  30  10   0
Greenville    68  82  66  88 /  50  30  10   0
Greenwood     67  82  65  88 /  50  40  10   0

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...Flood Watch through Saturday morning for MSZ049>052-054>066-
     072>074.

LA...Flood Watch through Saturday morning for LAZ024-026.

AR...None.
&&

$$

22/DC/NF