River Flood Warning 16, NWS Jackson, MS

Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
125 PM CDT Tue Jun 16 2026

...New AVIATION...

.KEY MESSAGES...

- Flooding remains likely across portions of the area this week,
  with flooding potential worsening into late week.

&&

.MESOSCALE UPDATE...
Issued at 1007 AM CDT Tue Jun 16 2026

Satellite imagery and regional radars showed deep convection along
the western Gulf coast and extending across our southern zones.
Our CWA remained south of a stalled frontal boundary and has a
very moist airmass in place with a PWAT in excess of 2 inches.
Latest trend on local radars was decrease in rainfall from the
northwest but moderate to heavy rainfall was continuing along and
south of the Highway 84 corridor. Latest guidance suggests the
heaviest rainfall today will continue across our southern most
zones before becoming much lighter this evening. A Flash Flood
Watch will remain in effect for this area as the rain amounts
stack up and the potential remains for very heavy rainfall in a
short amount of time. /22/

&&

.DISCUSSION...
Issued at 1258 AM CDT Tue Jun 16 2026

Today...

Mesoanalysis around midnight shows +theta-e advection still occuring
into the stalled frontal zone in the vicinity of I-20. This should
be the focus for storm development this morning. This round of heavy
rainfall could include as much as 4-5 inches, especially just south
and parallel the I-20 corridor. Because of this, and increasing
confidence for heavy rainfall impacts throughout the week, a
significant has been introduced in the HWO graphic. This roughly
matches with the moderate risk in the ERO by WPC. 3hr max QPF in the
REFs this morning shows multiple bullseyes of 4-7 inches, and the
mean is near the max, indicating the ceiling for rainfall this
morning into the afternoon.

Through early next week...

Coverage of rain should decrease Wednesday as the trough axis
passes, with reinforced shortwave ridging in advance of a tropical
Gulf low. The aforementioned feature will be the focus for the
second round of heavy rainfall, likely Thursday for our area. This
feature will carry with it a very moist airmass possibly in excess
of 2.5 inch PWAT. Given antecedent conditions, this additional round
would likely exacerbate flash flood threat, especially for areas
that receive great amounts today into tomorrow. While TC development
probabilities have increased, the primary threat of flash flooding
remains unchanged, therefore hazard messaging remains consistent.

There will also be a low end risk for severe associated with the
tropical low. Despite moist adiabatic lapse rates, low level shear
may be enhanced by the low. Along with significant deep moisture,
embedded low topped supercells cannot be ruled out, though the
risk remains low. The primary severe concerns would likely be wind
and perhaps a weak tornado within the tropical regime.

The boundary begins to make headway into the area by the weekend and
likely washes out this weekend. Airmass modification is likely slim,
but PWAT, while still supportive of additional rainfall, will be
more seasonal (1.5-1.7). This should provide some "break" from the
onslaught of moisture, with coverage overall more scattered this
weekend. Additional rainfall amounts Friday-Sunday generally look to
be in the 1 to 3 inch range, with focus along and south of the HWY
84 corridor. Southwesterly flow will continue to reinforce rain
chances through the remainder of the period, but increased
westerly/northwesterly flow by the middle next week may mean that
relief may be on the way. /SAS/

&&

.AVIATION...
(18Z TAFS)
Issued at 118 PM CDT Tue Jun 16 2026

GLH-GWO wl remain in VFR until after 06Z tonight. Elsewhere a mix
of MVFR/IFR conditions along with periods of -RA/-SHRA wl continue
until after 07Z when LIFR cigs wl develop and prevail through 14Z.
Conditions wl slowly improve to MVFR cigs by 17Z. A gusty sw-s
wind 18-22kt wl develop at GLH-GWO by 15Z Wed and continue through
the end of the TAF period. /22/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       81  71  88  74 /  90  20  40  80
Meridian      79  70  88  74 / 100  30  50  80
Vicksburg     83  71  88  74 /  80  10  30  70
Hattiesburg   79  71  86  75 / 100  30  50  80
Natchez       81  72  88  75 / 100  10  50  90
Greenville    86  71  90  75 /  10   0  10  40
Greenwood     85  71  91  75 /  30  10  20  60

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...Flood Watch through Thursday evening for MSZ040>066-072>074.

LA...Flood Watch through Thursday evening for LAZ009-015-016-023>026.

AR...None.
&&

22/SAS20/22