Alert archive / Louisiana / Flash Flood Warnings in 2025

Flash Flood Warning 7, NWS New Orleans, LA

March 30, 2025Saint Tammany Parish, Louisiana; Hancock County, Mississippi

NWS New Orleans, LA issued this flash flood warning at Mar 30, 2025, 3:27 PM CDT for Saint Tammany Parish, Louisiana; Hancock County, Mississippi. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Mar 30, 2025, 3:27 PM CDT (20:27 UTC)
Expired
Mar 30, 2025, 5:41 PM CDT
In force
2 hr
Issued by
NWS New Orleans, LA
Area
Storm-based polygon
Flood severity
None

Counties Saint Tammany Parish, LA, Hancock County, MS

The radar

The Hammond radar (KHDC), 68 km from the middle of the area, began a volume at 20:28 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, 8.5 hours before the alert went out and 17 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-pSkew-T log-p diagram, Slidell Radar S, LA at 12:00Z on 2025-03-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1280 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Slidell Radar S, LA at 12:00Z on 2025-03-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 197 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
1280 J/kg
Mixed-layer CIN
-15 J/kg
Mixed-layer LCL
532 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
197 m²/s²
0-3 km storm-relative helicity
249 m²/s²
Significant tornado parameter
0.7
Supercell composite
3.9

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood 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 flash flood warning went out at Mar 30, 11:19 AM CDT, 4 hours 8 minutes earlier.

Area forecast discussion, Mar 30, 11:19 AM CDT, 4 hours 8 minutes before
Area Forecast Discussion
National Weather Service New Orleans LA
1119 AM CDT Sun Mar 30 2025

...New AVIATION...

.SHORT TERM...
(Today through Monday)
Issued at 317 AM CDT Sun Mar 30 2025

Textbook wake low that developed last evening is now moving well
east of the area this morning. Some short term stability due to a
nice 1C inversion at 1700ft. But all guidance is still developing
some convection over the Miss gulf coastal counties around daylight
today. And as usual with these small scale systems, these models are
in disagreement on where to place it. We will leave the flood watch
for the eastern portion of the area but cancel it for the western.
We are in between systems now. The cold front that is moving into
the area will provide a lot of sfc support in the form of forcing to
storms. The environment has not changed outside the subsidence on
the back side of the wake low that has stabilized the area this
morning. This stability will hold until early Monday morning. Storms
forming along the front will be more than capable of producing
severe weather with all modes possible. The main variables would be
damaging winds and hail with some tornadoes possible. Heavy rain
will accompany these storms but they will be moving at a good pace.
But given antecedent conditions, we are already primed with
saturated grounds, and it wouldn't take much to push some of the
hardest hit areas into flooding. There is some indications of
another MCS structure developing along the dry line in south
central TX and move NE toward the new front(movinmg in from the
north) later today. This area is shown in all models but the
behavior is different some. They all have this feature moving NE
until it reaches the front, it then explodes with storms over NE
TX through northern Miss via help from the front. The front then
moves this area SE while allowing H7 dry air to entrain causing
the mass to accelerate SE outrunning the front and diving through
south central and or SE LA. This occurs between midnight and
daylight Monday morning. This is quite possible and if it does get
going, we should see it exhibiting these behaviors well before it
runs through here. This scenario would give some very strong
storms with all the baggage.

The front stalls along or near the coast Monday as the H7 ridge
moves over it. This causes dissapation of the rain that will be with
it as it moves in, and keeps anything else from developing while it
is stalled.

&&

.LONG TERM...
(Monday night through Saturday)
Issued at 317 AM CDT Sun Mar 30 2025

The front will begin to move back to the north as a warm front
Tuesday. Guidance is beginning to slow the next front moving east by
mid next week. The placement of this boundary will be very important
for folks north of us as it will cause some very dangerous flooding
concerns. Down this way though, we may see some showers from time to
time but this is mainly due to convergent sfc flow with moisture
loading for most of next week.

&&

.AVIATION...
(18Z TAFS)
Issued at 1117 AM CDT Sun Mar 30 2025

MVFR conditions prevail at all area aiports. A frontal system will
be moving through the area overnight tonight into the daytime
hours tomorrow, which will lower ceilings and visibilties. The
flight category should remain MVFR with brief drops to IFR as a
result. Gusty winds will also be expected as the system moves
through the area. MSW

&&

.MARINE...
Issued at 317 AM CDT Sun Mar 30 2025

Wind direction will remain SE to S at 10-15kt through much of this
week. A cold front will move to the coast and stall Monday and there
is the possibility that at least some of the coastal waters
temporarily develop a north wind at 10-15kt late Monday. But this
front will quickly become a warm front moving north bringing
southerly flow back to the northern gulf Tuesday which will remain
through the rest of the week.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  67  83  57  82 /  70  80  10  20
BTR  70  83  62  83 /  50  70  10  10
ASD  69  85  62  83 /  20  80   0  10
MSY  71  83  66  82 /  20  70   0  10
GPT  67  80  61  77 /  20  80   0  10
PQL  66  82  60  80 /  20  80   0  10

&&

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

SHORT TERM...TE
LONG TERM....TE
AVIATION...MSW
MARINE...TE

In the hours before

Special weather statement, Mar 30, 12:40 PM CDT, 2 hours 47 minutes before
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Special weather statement, Mar 30, 12:45 PM CDT, 2 hours 42 minutes before
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Special weather statement, Mar 30, 2:51 PM CDT, 36 minutes before
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Local storm report, Mar 30, 3:13 PM CDT, 14 minutes before
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Special weather statement, Mar 30, 3:16 PM CDT, 11 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Mar 30, 12:40 PM CDTSpecial Weather StatementLIXGeorge35 min
Mar 30, 12:45 PM CDTSpecial Weather StatementLIXGeorge30 min
Mar 30, 2:51 PM CDTSpecial Weather StatementLIXJackson24 min
Mar 30, 3:02 PM CDTFlash Flood WarningLIXHarrison, Jackson102 min
Mar 30, 3:16 PM CDTSpecial Weather StatementLIXGeorge29 min

Nearby

Flash Flood Warnings in Louisiana, 2025Flash Flood Warnings in Mississippi, 2025Every flash flood warning in 2025

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.