Alert archive / Louisiana / Mesoscale Discussions in 2016

Mesoscale Discussion 11

January 9, 2016Jefferson Parish, Lafourche Parish, Plaquemines Parish, Louisiana

The Storm Prediction Center issued this mesoscale discussion at Jan 9, 2016, 5:28 AM CST for Jefferson Parish, Lafourche Parish, Plaquemines Parish, Louisiana. It was in force for 62 min.

The area

The outline as issued.

The facts

Issued
Jan 9, 2016, 5:28 AM CST (11:28 UTC)
Expired
Jan 9, 2016, 6:30 AM CST
In force
62 min
Issued by
the Storm Prediction Center

Counties Jefferson Parish, LA, Lafourche Parish, LA, Plaquemines Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 11.5 hours before the alert went out and 129 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 00:00Z on 2016-01-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 00:00Z on 2016-01-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 47 square meters per square second.1939587897117136156Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
767 m above ground
0-6 km bulk shear
51 kt
0-1 km storm-relative helicity
47 m²/s²
0-3 km storm-relative helicity
86 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

462 
ACUS11 KWNS 091129
SWOMCD
SPC MCD 091128 
LAZ000-091230-

MESOSCALE DISCUSSION 0011
NWS STORM PREDICTION CENTER NORMAN OK
0528 AM CST SAT JAN 09 2016

AREAS AFFECTED...SOUTHEAST LOUISIANA

CONCERNING...SEVERE THUNDERSTORM WATCH 2...

VALID 091128Z - 091230Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 2 CONTINUES.

SUMMARY...A LIMITED SEVERE WEATHER THREAT ACROSS THE REMAINING VALID
PORTION OF SEVERE TSTM WATCH 2 IN SOUTHEAST LA AND EAST ACROSS FAR
SOUTHEAST LA /THROUGH PLAQUEMINES PARISH/ SUGGESTS THIS WATCH SHOULD
EXPIRE AT 12Z.

DISCUSSION...TRENDS IN EARLY MORNING SURFACE OBSERVATIONS INDICATED
THE WARM FRONT HAS REMAINED OFFSHORE TERREBONNE AND LAFOURCHE
PARISHES...WHILE CONTINUING TO EXTEND THROUGH SOUTHEAST PLAQUEMINES
PARISH /NEAR OR MORE LIKELY SOUTHEAST OF KBVE/.  MOSAIC RADAR
IMAGERY INDICATED AN EXTENSIVE AREA OF PRECIPITATION HAS SPREAD
ACROSS MUCH OF SOUTHEAST LA...AHEAD OF THE PRIMARY BAND OF
TSTMS...WHICH AT 1115Z EXTENDED FROM ST. CHARLES TO TERREBONNE
PARISHES AND INTO THE NORTHWEST GULF OF MEXICO.  A COUPLE OF STORMS
OFFSHORE NEAR AND AHEAD OF THE PRIMARY BAND...AND AT LEAST ONE STORM
INLAND HAVE HAD ROTATION...THOUGH THE OFFSHORE STORMS HAVE THE
GREATEST TORNADO POTENTIAL...SINCE THE INLAND STORMS ARE ELEVATED. 
THE EXTENSIVE AREA OF PRECIPITATION WILL CONTINUE TO SPREAD ACROSS
SOUTHEAST LA THIS MORNING...PRECEDING THE RELATIVELY STRONGER
STORMS...AND SHOULD LIMIT DESTABILIZATION.  THIS FACTOR AND THE
SMALL AREAL COVERAGE REMAINING FOR ANY ADDITIONAL SEVERE-WEATHER
THREAT APPEARS TO PRECLUDE THE NEED FOR ADDITIONAL WATCHES IN
SOUTHEAST LA.

..PETERS.. 01/09/2016

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...LIX...

LAT...LON   28719127 29539063 29729020 29678969 29548912 29088901
            28848918 28748969 28689017 28719127

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jan 8, 6:31 PM CSTMesoscale DiscussionSPCAcadia, Allen, Beauregard, Caddo, Calcasieu, Cameron and 7 more119 min
Jan 8, 9:52 PM CSTMesoscale DiscussionSPCAcadia, Allen, Ascension, Assumption, Beauregard, Calcasieu and 13 more83 min
Jan 8, 10:44 PM CSTSevere Thunderstorm WatchSPCAcadia, Allen, Ascension, Assumption, Avoyelles, Calcasieu and 19 more7 hr
Jan 9, 2:52 AM CSTMesoscale DiscussionSPCAcadia, Ascension, Assumption, Cameron, East Baton Rouge, Evangeline and 15 more113 min

Nearby

Mesoscale Discussions in Louisiana, 2016Every mesoscale discussion in 2016

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.