Alert archive / Louisiana / Mesoscale Discussions in 2016
Mesoscale Discussion 480
The Storm Prediction Center issued this mesoscale discussion at Apr 28, 2016, 3:56 AM CDT for 4 states. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 28, 2016, 3:56 AM CDT (08:56 UTC)
- Expired
- Apr 28, 2016, 6:00 AM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 5%
All 26 counties
Baldwin County, AL, Escambia County, AL, Mobile County, AL, Escambia County, FL, Okaloosa County, FL, Santa Rosa County, FL, Ascension Parish, LA, Assumption Parish, LA, Iberville Parish, LA, Livingston Parish, LA, Orleans Parish, LA, Saint Bernard Parish, LA, Saint Charles Parish, LA, Saint James Parish, LA, Saint John the Baptist Parish, LA, Saint Tammany Parish, LA, Tangipahoa Parish, LA, Washington Parish, LA, George County, MS, Greene County, MS, Hancock County, MS, Harrison County, MS, Jackson County, MS, Pearl River County, MS, Perry County, MS, Stone County, MS
The radar
The Mobile radar (KMOB), 69 km from the middle of the area, began a volume at 08:56 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 00:00Z, 8.9 hours before the alert went out and 80 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.
- Mixed-layer CAPE
- 148 J/kg
- Mixed-layer CIN
- -346 J/kg
- Mixed-layer LCL
- 1552 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 261 m²/s²
- 0-3 km storm-relative helicity
- 369 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted.
080
ACUS11 KWNS 280857
SWOMCD
SPC MCD 280856
FLZ000-ALZ000-MSZ000-LAZ000-281100-
MESOSCALE DISCUSSION 0480
NWS STORM PREDICTION CENTER NORMAN OK
0356 AM CDT THU APR 28 2016
AREAS AFFECTED...CENTRAL GULF COAST
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 280856Z - 281100Z
PROBABILITY OF WATCH ISSUANCE...5 PERCENT
SUMMARY...ISOLATED MARGINALLY SEVERE HAIL AND LOCALLY DAMAGING WIND
ARE POSSIBLE THIS MORNING WITH STORM COVERAGE POTENTIALLY BECOMING
WIDELY SCATTERED FROM SOUTHEAST LA TO THE WEST FL PANHANDLE.
DISCUSSION...MODEST LOW-LEVEL WAA IS SUPPORTING AN UPTICK IN
CONVECTION ACROSS SOUTHEAST LA INTO SOUTHWEST AL. UPSTREAM AIR MASS
IS CHARACTERIZED BY 70-75 DEG F SURFACE DEW POINTS OVER SOUTHEAST LA
AND ADJACENT GULF WATERS. 00Z LCH/LIX RAOBS SAMPLED STEEP 700-500 MB
LAPSE OF 7-7.5 DEG C/KM. WITH WEST-SOUTHWESTERLIES PERSISTING WITHIN
THIS LAYER PER LIX VWP DATA...IT IS LIKELY THAT THIS PERIPHERY OF
THE EML HAS BEEN MAINTAINED AND IS CONTRIBUTING TO MODERATE BUOYANCY
WITH MUCAPE OF 1000-2000 J/KG. DEEP-LAYER VEERING OF THE WIND
PROFILE WITH HEIGHT MAY SUPPORT SEMI-ORGANIZED UPDRAFT ROTATION
WHICH COULD FOSTER A FEW INSTANCES OF MARGINALLY SEVERE HAIL AND
PERHAPS LOCALLY DAMAGING WINDS THROUGH MID-MORNING.
..GRAMS/EDWARDS.. 04/28/2016
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...TAE...MOB...JAN...LIX...LCH...
LAT...LON 30249149 30689085 31118932 31348825 31378749 31198674
30998642 30698635 30538641 30268734 30048890 29638990
29719133 29959175 30249149SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 28, 10:02 AM CDT | Mesoscale Discussion | SPC | Escambia | 2 hr |
Nearby
Mesoscale Discussions in Louisiana, 2016Mesoscale Discussions in Mississippi, 2016Mesoscale Discussions in Alabama, 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; radar from the NEXRAD Level II archive.