Damaging Wind in Mississippi, June 12, 2023

Area Forecast Discussion...UPDATED
National Weather Service Mobile AL
638 PM CDT Mon Jun 12 2023

...New AVIATION...

.AVIATION...
(00Z TAFS)
Issued at 632 PM CDT Mon Jun 12 2023

Numerous showers and storms will gradually diminish by late
evening as the convection moves southeastward toward and off the
coast. Isolated to scattered showers and storms may redevelop
again late tonight, followed by scattered to numerous showers and
storms Tuesday morning. MVFR to IFR conditions will accompany the
stronger storms along with strong gusty winds and potentially
hail. Some patchy light fog is possible tonight. Southwest to west
winds around 10 knots diminishes tonight then a mostly southwest
flow at 5 to 10 knots follows for Tuesday. /22

&&

.PREV DISCUSSION... /issued 319 PM CDT Mon Jun 12 2023/

..New NEAR TERM, SHORT TERM, LONG TERM, MARINE...

NEAR TERM...
(Now through Tuesday)
Issued at 315 PM CDT Mon Jun 12 2023

An upper low drifts across the Great Lakes during the period while
an upper ridge over the southern/central Plains dampens to a
nearly zonal flow in response to a shortwave system. A weak
frontal boundary, mostly a surface trof, currently extends roughly
east-west across the central portion of the forecast area and is
expected to slowly drift towards central Mississippi/Alabama
through Tuesday afternoon. High CAPE values will be in place this
afternoon, near 4000 J/kg with only a modest decrease overnight,
then look to range from 2500-3500 J/kg on Tuesday. Shear values
trend higher through the period, with 0-6 km bulk shear values of
25-35 knots this afternoon increasing to 35-50 knots late tonight
followed by values of 40-50 knots on Tuesday. A series of
shortwaves moving across the area and interacting with the slow
moving frontal boundary and rather unstable environment is
expected to lead to MCS development through the period, although
the timing of the MCS's is less certain. After examining the
latest CAMS, have opted to increase pops today to
likely/categorical for much of the area with chance pops for this
evening. An MCS looks to develop upstream of the area overnight
then progress mostly across the interior portion of the forecast
area on Tuesday, although due to timing uncertainties could begin
late tonight. Have continued with slight chance/chance pops for
overnight then chance to likely pops follow for Tuesday with the
higher pops generally across interior areas. Damaging wind gusts
and large hail look to be the main threats from severe storms that
develop for this afternoon through Tuesday, although with the
shear increasing cannot rule out the potential for a tornado or
two over interior areas mainly during the day on Tuesday. Based on
beach reports, have gone with a moderate risk of rip currents for
the rest of today into tonight. Lows tonight range from the
mid/upper 60s well inland to the lower/mid 70s elsewhere. Highs on
Tuesday will be mostly in the upper 80s to lower 90s. /29

SHORT TERM...
(Tuesday night through Thursday night)
Issued at 315 PM CDT Mon Jun 12 2023

The shortwave conga line continues into the short term period.
Likewise, the potential continues for multiple rounds of strong to
severe thunderstorms associated with southeastward propagating
MCS's both Wednesday and Thursday. The sub-tropical jet
strengthens across the area with each shortwave that rounds the
periphery of a large cutoff upper level low centered across the
Great Lakes region. Models differ quite a bit on the evolution of
shortwaves during the short term period, with primary differences
associated with timing. Exact location of higher severe potential
will be hard to pinpoint until we see how Tuesdays MCS('s) evolve
and where the resultant remnant outflow boundary ends up. High
CAPE values in excess of 3,000 to 5,000+ j/kg along with long,
straight line hodographs yielding strong deep layer shear of 45 to
55+kts combined with DCAPE values of 1,000 to 1,500j/kg will set
the stage for initially splitting supercells with storms growing
quickly upscale into bowing segments. Given the higher LFC's, weak
low level shear and strong mid level shear it stands to reason
that any discrete convection would have the risk for damaging
winds and large hail, but once things grow upscale the threat will
shift to primarily damaging winds. Additionally, we also advect
in rather steep mid-level lapse rates upwards of around 8C/km
which only bolsters the potential for potent storms. If a robust
MCS can materialize with a well developed cold pool I can't rule
out the potential for isolated instances of intense damaging wind
gusts to 75mph. If storms stay discrete in the area for an
appreciable amount of time Wednesday, large hail up to around 2
inches in diameter can't be ruled out. A best guess at timing
right now would be sometime late morning Wednesday into the
afternoon hours, although this could shift to be earlier or later.
Timing will hopefully be refined as we move forward into
tomorrow.

Regardless of storm evolution, it's likely going to remain warm
across the forecast area. High temperatures remain in the upper
80's inland with lower to middle 90's elsewhere. Low temperatures
stay in the upper 60's over far interior areas with lower to
middle 70's elsewhere. The immediate coast will likely see upper
70's for lows. The rip current risk will be increasing into
Wednesday and Thursday, with a moderate risk Wednesday into
Wednesday night and high risk Thursday into Thursday night. MM/25

LONG TERM...
(Friday through Monday)
Issued at 315 PM CDT Mon Jun 12 2023

An upper level ridge located over Latin America builds east and
northeast. A closed upper low over New England moves off, with
another shortwave system moving over the Great Lakes and
organizing into a closed low by Sunday. This upper low shifts
south Sunday into the coming week, shifting south a bit the upper
ridge that has built east over the northern Gulf coast. Upper
level shortwave energy continues to be directed over the South. A
surface ridge stretching west over the central/southern Gulf of
Mexico continues to bring south to southwest low level flow to the
norther Gulf coast, re-enforcing a very moist airmass over the
Southeast. Weak surface cold fronts move south across the
Southeast at times with the passing shortwaves, with the
boundaries stalling between the I-20 and I-10 corridors. Timing of
these shortwaves has been inconsistent, both between models and
run-to-run, so am not going to try and pin down timing at this
time. These surface boundaries along with a daily seabreeze moving
inland from the Gulf will provide the focus for showers and
thunderstorms when present. With the upper ridge affecting western
portions of the forecast area the most, temperatures are expected
to be higher west of the Tombigbee River with PoPs higher east.
Temperatures are expected to range from above to well above
seasonal norms in the extended, with Heat Indices topping out in
the 100-107 degree range over mainly the southwestern half of the
forecast through the extended are expected. Also, the risk of
strong to severe storms continues, with abundant instability
(MLCapes of 2500- 3500J/kg) from the hot temperatures and abundant
wind shear Friday (Bulk Shear values of 35-50kts). Wind shear
eases a bit through the weekend, but remains higher than usual for
summer (30-40kts). With the boundaries floating around over and
near the forecast area, will need to monitor for strong to severe
storms, with subsidence from the upper ridge governing where the
best chance lies. Strong winds and large hail remain the likely
modes of damage.

/16

MARINE...
Issued at 315 PM CDT Mon Jun 12 2023

A light to moderate southwesterly flow will prevail through
Tuesday, then strengthens temporarily on Wednesday before
returning to a light to moderate flow. Small craft may need to
exercise caution mainly on Wednesday. /29

&&

.PRELIMINARY POINT TEMPS/POPS...
Mobile      72  91  75  91  73  90  73  92 /  40  30  40  70  30  70  30  50
Pensacola   77  89  78  89  76  88  74  89 /  30  40  40  60  40  70  50  50
Destin      78  88  79  88  78  87  75  89 /  30  40  40  50  40  70  50  50
Evergreen   69  91  71  92  70  88  69  93 /  40  60  40  70  60  70  40  40
Waynesboro  68  89  70  90  68  90  71  93 /  30  50  40  70  60  70  30  40
Camden      66  87  67  87  66  86  68  91 /  30  70  60  80  70  70  40  40
Crestview   71  92  73  92  71  90  70  93 /  40  60  30  70  50  70  40  50

&&

.MOB WATCHES/WARNINGS/ADVISORIES...
AL...None.
FL...None.
MS...None.
GM...None.
&&

This product is also available on the web at:
www.weather.gov/mob

Preliminary Local Storm Report
National Weather Service Mobile AL
836 PM CDT Mon Jun 12 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0829 PM     Tstm Wnd Gst     4 ESE Fort Walton Beach 30.40N 86.57W
06/12/2023  M54 MPH          GMZ635             FL   Mesonet

            Fort Walton Beach recorded a max wind gust
            of 47 knots.

&&

JEH

Preliminary Local Storm Report
National Weather Service Mobile AL
838 PM CDT Mon Jun 12 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0837 PM     Tstm Wnd Gst     3 ESE Fort Walton Beach 30.40N 86.58W
06/12/2023  M49 MPH          GMZ635             FL   Mesonet

            Fort Walton Beach recorded a wind gust of 43
            knots.

&&

JEH

Preliminary Local Storm Report
National Weather Service Mobile AL
851 PM CDT Mon Jun 12 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0834 PM     Tstm Wnd Gst     2 SE Ocean City         30.43N 86.59W
06/12/2023  M42 MPH          GMZ635             FL   Mesonet

            CWOP site FW2930 recorded a max wind gust of
            36 knots.

&&

JEH

Preliminary Local Storm Report
National Weather Service Mobile AL
856 PM CDT Mon Jun 12 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0844 PM     Tstm Wnd Gst     4 ESE Fort Walton Beach 30.40N 86.57W
06/12/2023  M47 MPH          GMZ635             FL   Public

            FWB weather flow station recorded wind gusts
            ranging from 34-41 kts for about 10 min
            beginning at 844pm. Max gust of 41kts during
            this time.

&&

JEH

Preliminary Local Storm Report
National Weather Service Mobile AL
903 PM CDT Mon Jun 12 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0840 PM     Tstm Wnd Gst     2 ESE Destin            30.39N 86.47W
06/12/2023  M40 MPH          Okaloosa           FL   ASOS

            KDTS recorded a max wind gust of 35knots.

&&

JEH

Preliminary Local Storm Report...Summary
National Weather Service Mobile AL
922 PM CDT Mon Jun 12 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0433 PM     Tstm Wnd Dmg     Richton                 31.35N 88.94W
06/12/2023                   Perry              MS   Public

            Public report with video of multiple trees
            down in Richton. Time estimated based on
            radar.

0748 PM     Tstm Wnd Gst     East End of Dauphin     30.26N 88.08W
06/12/2023  E42 MPH          GMZ631             AL   Mesonet

            Fort Gaines recorded a max wind gust of
            37knots.

0829 PM     Tstm Wnd Gst     4 ESE Fort Walton Beach 30.40N 86.57W
06/12/2023  M54 MPH          GMZ635             FL   Mesonet

            Fort Walton Beach recorded a max wind gust
            of 47 knots.

0834 PM     Tstm Wnd Gst     2 SE Ocean City         30.43N 86.59W
06/12/2023  M42 MPH          GMZ635             FL   Mesonet

            CWOP site FW2930 recorded a max wind gust of
            36 knots.

0837 PM     Tstm Wnd Gst     3 ESE Fort Walton Beach 30.40N 86.58W
06/12/2023  M49 MPH          GMZ635             FL   Mesonet

            Fort Walton Beach recorded a wind gust of 43
            knots.

0844 PM     Tstm Wnd Gst     4 ESE Fort Walton Beach 30.40N 86.57W
06/12/2023  M47 MPH          GMZ635             FL   Public

            FWB weather flow station recorded wind gusts
            ranging from 34-41 kts for about 10 min
            beginning at 844pm. Max gust of 41kts during
            this time.

0840 PM     Tstm Wnd Gst     2 ESE Destin            30.39N 86.47W
06/12/2023  M40 MPH          Okaloosa           FL   ASOS

            KDTS recorded a max wind gust of 35knots.

0740 PM     Tstm Wnd Gst     Dauphin Island          30.26N 88.11W
06/12/2023  M57 MPH          Mobile             AL   Public

            Dauphin Island resident records thunderstorm
            wind gust of 57mph. Additional 52mph wind
            gust measured around 7:50 PM as well.

&&