Alert archive / Mississippi / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 65, NWS New Orleans, LA

May 20, 2020Jackson County, Mississippi

NWS New Orleans, LA issued this severe thunderstorm warning at May 20, 2020, 3:49 PM CDT for Jackson County, Mississippi. It was in force for 26 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: May 20, 2020, 3:49 PM CDT (20:49 UTC)
Expired: May 20, 2020, 4:15 PM CDT
In force: 26 min
Issued by: NWS New Orleans, LA
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County Jackson County, MS

The radar

The Mobile radar (KMOB), 44 km from the middle of the area, began a volume at 20:48 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 8.8 hours before the alert went out and 106 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 582 J/kg
Mixed-layer CIN: -153 J/kg
Mixed-layer LCL: 710 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 127 m²/s²
0-3 km storm-relative helicity: 198 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 6.4

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, 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 this severe thunderstorm warning went out at May 20, 4:02 AM CDT, 11 hours 47 minutes earlier.

Area forecast discussion, May 20, 4:02 AM CDT, 11 hours 47 minutes before

Area Forecast Discussion
National Weather Service New Orleans LA
402 AM CDT Wed May 20 2020

.SHORT TERM...
Overcast skies will limit daytime heating for much of today which
might slow the potential for severe storms as temperatures remain
at or below 80 throughout most of the day. Weak high pressure
will remain over the northern Gulf and slowly migrate eastward
throughout the week. As a result a deeper column of high moisture
return flow allowing a tropical air mass to stream into our region
from the central and southern Gulf. This will bring a widespread
continuation of shower and thunderstorm activity through the
remainder of the forecast period. Locally heavy rainfall is
possible on any given day as this pattern persists. The showers
and thunderstorms will be mostly diurnally driven thus not
expecting any widespread heavy rainfall totals at this time. Max
temperatures will remain slightly above normal with low
temperatures being well above normal given the higher dewpoints as
tropical airmass settles.

&&

.AVIATION...
MVFR to VFR conditions expected at most terminals today but
ceilings will gradually lower through the day becoming more IFR by
this evening with the exception of some TS activity that will be
moving through causing at least temporary IFR and possibly LIFR
conditions.

&&

.MARINE...
Weak high pressure will remain over much of the Gulf of Mexico
for much of the week. The Bermuda ridge will begin to bring deep
southeasterly winds back to the area by Thursday and these
conditions are expected to remain into the new week mainly around
10-15kt.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  78  66  86  70 /  30  10  20   0
BTR  78  68  89  70 /  50  10  10   0
ASD  78  66  89  70 /  40  10  10   0
MSY  81  71  89  73 /  20  10   0   0
GPT  77  68  84  72 /  60  10  20   0
PQL  79  65  87  69 /  50  10  20   0

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...None.
GM...None.
MS...None.
GM...None.
&&

In the hours before

Special weather statement, May 20, 1:44 PM CDT, 2 hours 5 minutes before

Special Weather Statement
National Weather Service New Orleans LA
144 PM CDT Wed May 20 2020

LAZ039-MSZ077-201930-
Washington-Pearl River-
144 PM CDT Wed May 20 2020

...A STRONG THUNDERSTORM WILL AFFECT EASTERN WASHINGTON PARISH IN
SOUTHEASTERN LOUISIANA AND NORTHWESTERN PEARL RIVER COUNTIES...

At 144 PM CDT, a strong thunderstorm was located near Franklinton,
moving southeast at 30 mph.

Winds in excess of 30 mph and half inch hail are possible with this
storm.

Locations impacted include...
Bogalusa, Franklinton, Poplarville, Varnado, Crossroads and Mcneil.

If outdoors, consider seeking shelter inside a building.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

LAT...LON 3084 8954 3060 8966 3084 9019 3100 9010
      3100 9007
TIME...MOT...LOC 1844Z 293DEG 27KT 3090 9007

PG

Special weather statement, May 20, 1:46 PM CDT, 2 hours 3 minutes before

Special Weather Statement
National Weather Service New Orleans LA
146 PM CDT Wed May 20 2020

LAZ039-071-MSZ070-071-201915-
Washington-Northern Tangipahoa-Pike-Walthall-
146 PM CDT Wed May 20 2020

...A STRONG THUNDERSTORM WILL AFFECT NORTHERN TANGIPAHOA AND
NORTHWESTERN WASHINGTON PARISHES...SOUTHWESTERN WALTHALL AND SOUTHERN
PIKE COUNTIES...

At 145 PM CDT, a strong thunderstorm was located over Osyka, or 17
miles south of Mccomb, moving east at 40 mph.

Winds in excess of 30 mph and half inch hail are possible with this
storm.

Locations impacted include...
Franklinton, Kentwood, Osyka and Mount Herman.

If outdoors, consider seeking shelter inside a building.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

LAT...LON 3093 9056 3110 9049 3098 8998 3073 9009
TIME...MOT...LOC 1845Z 291DEG 33KT 3100 9045

PG

Special weather statement, May 20, 2:14 PM CDT, 1 hour 35 minutes before

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Special weather statement, May 20, 2:39 PM CDT, 1 hour 10 minutes before

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Local storm report, May 20, 2:42 PM CDT, 1 hour 7 minutes before

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    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
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Local storm report, May 20, 2:44 PM CDT, 1 hour 5 minutes before

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    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
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The office that day

Everything else NWS New Orleans, LA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 20, 12:12 PM CDT	Special Weather Statement	LIX	Pointe Coupee, West Feliciana	33 min
May 20, 12:43 PM CDT	Special Weather Statement	LIX	East Feliciana, West Feliciana	32 min
May 20, 1:26 PM CDT	Special Weather Statement	LIX	Tangipahoa	49 min
May 20, 1:27 PM CDT	Special Weather Statement	LIX	Saint Helena	48 min
May 20, 1:44 PM CDT	Special Weather Statement	LIX	Washington	46 min
May 20, 1:46 PM CDT	Special Weather Statement	LIX	Washington	29 min
May 20, 1:49 PM CDT	Severe Thunderstorm Warning	LIX	Saint Tammany, Tangipahoa	26 min
May 20, 2:06 PM CDT	Severe Thunderstorm Warning	LIX	Washington	24 min
May 20, 2:11 PM CDT	Severe Thunderstorm Warning	LIX	Saint Tammany	34 min
May 20, 2:14 PM CDT	Special Weather Statement	LIX	Washington	31 min
May 20, 3:43 PM CDT	Special Marine Warning	LIX		32 min
May 20, 2:39 PM CDT	Special Weather Statement	LIX	Hancock, Pearl River	51 min

Nearby

Severe Thunderstorm Warnings in Mississippi, 2020 Every severe thunderstorm warning in 2020

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.