Alert archive / Louisiana / Heat Advisories in 2016

Heat Advisory 2, NWS New Orleans, LA

July 5, 201613 parishes in Louisiana; 5 counties in Mississippi

NWS New Orleans, LA issued this heat advisory at Jul 5, 2016, 3:35 AM CDT for 13 parishes in Louisiana; 5 counties in Mississippi. It took effect at Jul 5, 2016, 10:00 AM CDT. It was in force for 9 hr.

The area

The counties it named.

The facts

Issued: Jul 5, 2016, 3:35 AM CDT (08:35 UTC)
In effect from: Jul 5, 2016, 10:00 AM CDT
Expired: Jul 5, 2016, 7:00 PM CDT
In force: 9 hr
Issued by: NWS New Orleans, LA

Counties Assumption Parish, LA, East Baton Rouge Parish, LA, East Feliciana Parish, LA, Iberville Parish, LA, Pointe Coupee Parish, LA, Saint Bernard Parish, LA, Saint Helena Parish, LA, Saint James Parish, LA, Saint John the Baptist Parish, LA, Tangipahoa Parish, LA, Washington Parish, LA, West Baton Rouge Parish, LA, West Feliciana Parish, LA, Amite County, MS, Pearl River County, MS, Pike County, MS, Walthall County, MS, Wilkinson County, MS

The nearest sounding before it

Jackson, MS (KJAN), launched 00:00Z, 8.6 hours before the alert went out and 198 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: 474 J/kg
Mixed-layer CIN: -146 J/kg
Mixed-layer LCL: 1269 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 138 m²/s²
0-3 km storm-relative helicity: 157 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this heat advisory 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 heat advisory went out at Jul 4, 3:32 PM CDT, 12 hours 3 minutes earlier.

Area forecast discussion, Jul 4, 3:32 PM CDT, 12 hours 3 minutes before

Area Forecast Discussion
National Weather Service New Orleans LA
332 PM CDT MON JUL 4 2016

.DISCUSSION...
Generally only minor tweaks made to the forecast with the only
real weather impact being the continuation of summer heat. High
pressure will dominate the area's weather through the week, which
will limit convective coverage each day. Generally expect no
better than isolated coverage through the week. With a lack of
convection and rain cooled downdrafts/outflow, afternoon temps
will continue to rise into the mid 90s each afternoon. Warmest
afternoons look to be Thursday and Friday. Afternoon heat index
values currently look to stay in the 100 to 105 range which is
admittedly uncomfortable but fairly normal for this time of year
in the Gulf Coast region.

Going into the weekend, high pressure will weaken as an upper low
moves through the Great Lakes region. this should allow a bit more
convection. Rain chances currently look highest on Sunday and will
carry solid chance PoPs.

&&

.AVIATION...
Biggest impact over the next few hours will be showers and
thunderstorms. The bulk of activity is currently moving across an
area northwest of a KHUM to KHDC line. These storms are moving
quite briskly at 30+ knots and likely have wind gusts around that
speed as well. Some storms could spread southeast of the current
location but not expecting as much coverage there. Convection will
diminish around sunset. Otherwise...vfr conditions will prevail
through the overnight period with light to calm winds.

&&

.MARINE...
Bermuda surface ridge extending across the Gulf of Mexico will
keep flow onshore the throughout the forecast period. A weak
upper level trough and associated surface trough moving east
across mid Mississippi Valley today has tightened the local
pressure gradient and kept the coastal water wind field mainly in
the 10 to 15 knot range. This should be the case through Tuesday.
Wednesday onward will be the typical diurnal nocturnal wind
increase to 10 to 15 knots which will carry over into the morning
hours and then drop down the rest of the day closer to 10 knots or
slightly less.

&&

.DECISION SUPPORT...
DSS code: Green.
Deployed: None.
Activation: None.
Activities: None.

Decision Support Services (DSS) Code Legend
Green  = No weather impacts that require action.
Blue   = Long-fused watch, warning, or advisory in effect or
         high visibility event.
Yellow = Heightened impacts with short-fused watch, warning
         or advisory issuances; radar support.
Orange = High Impacts; Slight to Moderate risk severe; nearby
         tropical events; HazMat or other large episodes.
Red    = Full engagement for Moderate risk of severe and/or
         direct tropical threats; Events of National Significance.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  76  93  74  93 /  20  30  10  20
BTR  77  95  77  94 /  10  30  10  20
ASD  78  93  77  93 /  10  20  10  20
MSY  79  93  79  94 /  10  20  10  20
GPT  80  93  79  92 /  10  20  10  20
PQL  76  91  77  92 /  10  20  10  20

&&

.LIX Watches/Warnings/Advisories...
LA...None.
GM...None.
MS...None.
GM...None.
&&

Hazardous weather outlook, Jul 4, 4:58 PM CDT, 10 hours 37 minutes before

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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
Jul 5, 1:00 PM CDT	Special Marine Warning	LIX		45 min
Jul 5, 3:44 PM CDT	Heat Advisory	LIX	Assumption, East Baton Rouge, East Feliciana, Iberville, Pointe Coupee, Saint Bernard and 7 more	27 hr
Jul 5, 2:17 PM CDT	Special Weather Statement	LIX	Amite	43 min
Jul 5, 3:30 PM CDT	Special Weather Statement	LIX	Pike, Walthall	45 min

Nearby

Heat Advisories in Louisiana, 2016 Heat Advisories in Mississippi, 2016 Every heat advisory 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.