A deep upper level system diving south across the midsection of the country was the main driver of an approaching cold front. As this boundary tracked east through Louisiana and Arkansas towards the local area, an increasing low level jet ushered in ample low/mid level moisture as well as provided modest wind shear.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS LIX wrote it up.
A deep upper level system diving south across the midsection of the country was the main driver of an approaching cold front. As this boundary tracked east through Louisiana and Arkansas towards the local area, an increasing low level jet ushered in ample low/mid level moisture as well as provided modest wind shear. At the surface, a warm front lifted north out of the Gulf of Mexico and well into Mississippi. This front increased moisture and temperatures at the surface. The combination of increasing low level temps and moisture with fall mid level temps resulted in an increasingly unstable atmosphere. This resultant environment was able to support a severe thunderstorm with damaging winds in Wilkinson County.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS New Orleans, LA wrote its last area forecast discussion before the first event at Nov 20, 5:37 PM CST, 2 hours 33 minutes earlier.
Area Forecast Discussion...UPDATED
National Weather Service New Orleans LA
537 PM CST Mon Nov 20 2023
...NEW AVIATION...
.SHORT TERM...
(This evening through Tuesday night)
Issued at 423 PM CST Mon Nov 20 2023
So what can we expect tonight. We are currently getting a balloon up
to see how much the environment has changed from the 12z flight this
morning. We will have another balloon up for 00z and that should
give us an even better idea of things. Biggest question marks are
how much have we recovered and how much of the strong cap around
h8 is still around.
There are a bunch of pros and cons with respect to severe weather
tonight but at a quick glance the main area of concern appears to be
southwest MS and adjacent LA parishes which fits the Enhanced area
but we can not rule out a few possible.
Southwest flow aloft will slowly but steadily increase through the
evening and it appears from GOES16 that there may be a little more
forcing coming across the western Gulf than what some models were
indicating and possibly why now the CAMs have been favoring coastal
convection and thus would cut off much of the land area from the
significant activity overnight which would be associated with the
front. Prior to that storms will likely begin to move into the area
around and shortly after 00z and this would be associated with the
development of a LL jet which the core may move right across
southwest MS during the evening hours. This is the location that
could be touch and go this evening. It would be before any
convection tries to fire to the south and could maximize the shear
and helicity values. This area should be far enough north and
removed from any possible marine layer with these storms most likely
sfc based. Farther to the south the marine layer does become a
concern, especially immediately along the north side of the lake
and across much of the SELA coast.
Also for areas along and south of I-12/10 there seem to be more
negative than positive with respect to severe weather. First this
location may have to contend with some minor marine layer issues but
the bigger concern is the LL jet which the tail end of it will move
across this area initially and then lift to the northeast and this
will lead to LL divergence which will hurt convection potential. In
addition the sfc pressure is expected to rise even with a weak front
approaching and the hghs aloft look like they may slightly rise
overnight as the main impulse pulls off to the northeast. The one
aspect that does seem to hint at possibly better potential is what
was mentioned earlier and that is GOES16 showing some slightly
better lift coming northeast out of the western Gulf but if this is
the case then there is a really good chance that robust convection
could develop overnight in the more unstable areas over the coastal
waters.
Front should move through most of the area around or shortly after
sunrise. Rain will come to an end after the front moves through and
much drier air will push back into the area. We see a reinforcing
shot of dry air early Wednesday as a strong disturbance drops out of
Canada and closes off over the Ozarks Tuesday night. That will help
keep your travel day Wednesday on the dry end with a low closing off
over the Baja Tuesday night. /CAB/
&&
.LONG TERM...
(Wednesday through Sunday night)
Issued at 423 PM CST Mon Nov 20 2023
Focus is mainly on the threat for tonight but Thanksgiving is
only a few days away and with multiple people on the road
Wednesday and out and about Friday through the weekend can't
completely gloss over the extended portion of the forecast.
Overall medium range guidance is in agreement however, there are
some differences with strength and specific features Thursday
night into Friday and on the back end of the weekend into next
week. Luckily even with the differences it is not anything of
significant impact and is more a light rain or no rain scenario so
with not strong lean one way or the other we will stick closely
to the NBM for now and try to get a better grasp on these features
tomorrow and Wednesday.
Very active pattern is already in place and likely to remain through
the forecast. The problem is trying to time specific
impulses/disturbances and how they strong they may be. After
tonight's weather the focus will shift towards how the strong
disturbance coming out of Canada reacts with the base of the highly
positively tilted trough across the CONUS. All indications are the
back end of our trough will break off and cut off over the Baja but
how fast does it start to kick out and how much latitude can it
climb. This will have a lot to say about where rain develops and if
it can move into the area Thursday evening and overnight. That said
even if the low starts to lift across seTX and through the Lower MS
Valley we would likely just see light rain with a few embedded spots
of moderate rain. Not expecting any lightning with that system. If
the disturbance opens up faster or is a little further south as it
lifts out then the rain would most likely be confined to the Gulf.
After it passes Friday morning we remain in WSW flow through
Saturday night as the next system tries to drop back down the
backside of the L/W. It is that system that models have the biggest
disagreement with as a much stronger deeper and closed low would be
slower and likely begin the work week dry where a much weaker and
more progressive system would possibly bring rain back into the area
Monday. /CAB/
&&
.AVIATION...
(00Z TAFS)
Issued at 532 PM CST Mon Nov 20 2023
VIS/CIG reductions anticipated through much of this cycle.
Convection tonight will develop generally from west to east with
the strongest activity having strong gusty winds and lightning.
This activity should clear the western terminals early morning and
the MS Gulf Coast an hour or two after sunrise. Behind the front
southerly winds will transition to a northwesterly direction with
some gusts in excess of 20kts. Some VIS/CIG improvements are
anticipated by the end of the cycle with the cloud deck lifting to
around 5kft. (Frye)
&&
.MARINE...
Issued at 423 PM CST Mon Nov 20 2023
Winds have been overachieving and have placed all of the waters
in a SCY through 12z. This is mostly for frequent gusts but even
at 21z most platforms and buoys were hitting 20kts sustained.
Likely to need some sort of headlines for most of the waters into
at least Wednesday, although there may be brief lulls in hazardous
conditions. Don't anticipate many, if any, periods of calm or
near calm conditions this week. /CAB/
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 58 64 43 56 / 100 10 10 10
BTR 60 66 46 60 / 90 10 10 10
ASD 63 71 47 60 / 100 20 10 10
MSY 66 69 52 60 / 90 10 20 10
GPT 64 73 49 60 / 100 40 20 20
PQL 64 75 47 61 / 90 60 20 10
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...None.
GM...Small Craft Advisory until 6 AM CST Tuesday for GMZ530-532-534-
536-538-550-552-555-557-570-572-575-577.
MS...None.
GM...Small Craft Advisory until 6 AM CST Tuesday for GMZ532-534-536-
538-550-552-555-557-570-572-575-577.
&&
SHORT TERM...CAB
LONG TERM....CAB
AVIATION...RDF
MARINE...CABThe national radar mosaic for the moment the first event began.
1 thunderstorm wind. Local standard time, as filed.
Local emergency manager reported multiple trees down from thunderstorm winds. Roads with reported trees down were Pinkneyville, Millbrook, Woodstock and Donegal.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Mississippi in 2023Every state in 2023This day in weather historyWarnings in Mississippi, November 2023
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-30. Each event’s entry at NCEI: 1148234.