Severe Thunderstorm Warning 49, NWS New Orleans, LA

599 
WWUS54 KLIX 182104
SVSLIX

Severe Weather Statement
National Weather Service New Orleans LA
404 PM CDT FRI MAY 18 2018

LAC033-037-077-121-125-182113-
/O.CAN.KLIX.SV.W.0049.000000T0000Z-180518T2115Z/
West Feliciana LA-West Baton Rouge LA-Pointe Coupee LA-
East Feliciana LA-East Baton Rouge LA-
404 PM CDT FRI MAY 18 2018

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN WEST FELICIANA...
NORTHEASTERN WEST BATON ROUGE...SOUTHEASTERN POINTE COUPEE...
SOUTHWESTERN EAST FELICIANA AND NORTHWESTERN EAST BATON ROUGE
PARISHES IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning has been cancelled.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
New Orleans.

LAT...LON 3062 9139 3077 9127 3066 9099 3043 9116
TIME...MOT...LOC 2101Z 303DEG 11KT 3063 9121 

$$

32

Area Forecast Discussion
National Weather Service New Orleans LA
344 PM CDT Fri May 18 2018

.SYNOPSIS...
Latest upper air analysis showed a low over eastern Missouri with
the associated ridge axis extending south toward the Northeast
Gulf of Mexico. In addition, a short wave was noted over northeast
Texas this morning embedded in the northwest flow. This wave has
dived southeast and lowered 5h temps from -8c to -10c. Also, 12z
sounding at Slidell revealed a wetbulb zero around 9300 feet. GFS
and NAM initialized a swath of 1.5 to 1.7 precipitable water value
of across west central Louisiana to northeast Texas, between
upper air plots. Radar continue to show afternoon convection
isolated to scattered in coverage.

Surface analysis showed a weak 1014mb high over north central Gulf
yielding southwest flow over southeast Louisiana and southern
Mississippi.

&&

.DISCUSSION...

Upper level trough axis will finally lift east tonight through
Saturday. At the same time, the ridge axis will shift east over
the Lower and Mid Mississippi valley Saturday. The exiting short
wave and the approach of the ridge axis will lower precipitable
water values with 1.5 across the east zones and 1.3 to 1.5 across
the west zones on Saturday. This dry air will continue to work
east through Saturday night. Therefore, convection coverage will
be sparse for Saturday. In addition, wetbulb zero will increase up
to 11kft on Saturday and hail threat should diminish. Lower rain
chances are expected over the weekend and temperatures will
continue to run above normal.

Weakening of the upper ridge across the Gulf Coast region next
week along higher moisture content air will lead to an overall
better chance for daily convection next work week and will be
typical of a summertime weather pattern. In addition, the broad
trough axis across the east gulf will remain over this region the
weekend. NAM and GFS tries to develop an upper level low over the
east gulf Monday and take it to north central gulf late Monday.
Euro ignores this features and we will maintain chance pops on
Monday. Precipitable water values remain between 1.4 and 1.6
inches next week and afternoon rain chances 30 to 40 percent will
be common next week. High temperatures are expected to be a bit
lower next week, but still above normal. 18

&&

.AVIATION...

VFR conditions will be the rule at all of the terminals, but there
will be some scattered convection this afternoon. Have VCTS
wording in place through 00z to reflect this risk, and have
amended the forecast if convection looks to impact a terminal. If
a storm passes over, a brief period of gusty winds and reduced
visibilities can be expected. Additionally, a period of MVFR
visibilities could develop around 12z at KMCB and KBTR due to
light fog. 32

&&

.MARINE...

Winds will have an onshore component through the forecast period.
Most of the time, winds should remain at or below 12 knots.
Cannot rule out a few locations briefly seeing 15-16 knots, but
this should not be prevailing, and don't think headlines will be
necessary. Convection will remain possible through the period, but
widespread areal coverage is not anticipated. 18

&&

.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; Marginal risk severe or excessive rain.
Yellow = Heightened impacts with short-fused watch, warning or
         advisory issuances; radar support for Slight risk severe or
         excessive rain.
Orange = High Impacts; Enhanced risk severe; nearby tropical events;
         HazMat or other large episodes.
Red    = Full engagement for Moderate to high risk of severe and/or
         direct tropical threats; Events of National Significance.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  69  91  69  91 /  20  20  20  30
BTR  71  91  71  91 /  20  10  10  30
ASD  69  90  70  90 /  20  20  20  20
MSY  74  90  74  90 /  20  20  20  20
GPT  74  88  74  89 /  20  20  20  20
PQL  69  88  70  89 /  20  20  20  20

&&

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

Hazardous Weather Outlook
National Weather Service New Orleans LA
1102 AM CDT Fri May 18 2018

GMZ530-532-534-536-538-550-552-555-557-570-572-575-577-LAZ034>037-
039-040-046>050-056>072-MSZ068>071-077-080>082-190415-
Lake Pontchartrain and Lake Maurepas-Mississippi Sound-
Lake Borgne-Chandeleur Sound-Breton Sound-
Coastal Waters from Port Fourchon LA to Lower Atchafalaya River
LA out 20 nm-
Coastal waters from the Southwest Pass of the Mississippi River
to Port Fourchon Louisiana out 20 NM-
Coastal Waters from Boothville LA to Southwest Pass of the
Mississippi River out 20 nm-
Coastal waters from Pascagoula Mississippi to Stake Island out
20 NM-
Coastal waters from Port Fourchon Louisiana to Lower Atchafalaya
River LA from 20 to 60 NM-
Coastal waters from Southwest Pass of the Mississippi River to
Port Fourchon Louisiana from 20 to 60 NM-
Coastal Waters from Stake Island LA to Southwest Pass of the
Mississippi River from 20 to 60 nm-
Coastal waters from Pascagoula Mississippi to Stake Island
Louisiana out 20 to 60 NM-Pointe Coupee-West Feliciana-
East Feliciana-St. Helena-Washington-St. Tammany-Iberville-
West Baton Rouge-East Baton Rouge-Ascension-Livingston-Assumption-
St. James-St. John The Baptist-Upper Lafourche-St. Charles-
Upper Jefferson-Orleans-Upper Plaquemines-Upper St. Bernard-
Upper Terrebonne-Lower Terrebonne-Lower Lafourche-Lower Jefferson-
Lower Plaquemines-Lower St. Bernard-Northern Tangipahoa-
Southern Tangipahoa-Wilkinson-Amite-Pike-Walthall-Pearl River-
Hancock-Harrison-Jackson-
1102 AM CDT Fri May 18 2018

This Hazardous Weather Outlook is for portions of Southeast
Louisiana...South Mississippi and the adjacent coastal waters.

.DAY ONE...This Afternoon and Tonight

Isolated to scattered thunderstorms are possible, mainly during
the afternoon and early evening hours. A few storms could become
strong to severe. Gusty winds, hail and frequent lightning will
be possible with the strongest storms.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday

Isolated to scattered showers and thunderstorms will be possible
each day through Thursday. A few strong to severe thunderstorms
will be possible. The main hazard would be strong downburst winds,
though hail and periods of frequent lightning will also be a
concern.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated.

32

Special Weather Statement
National Weather Service New Orleans LA
307 PM CDT FRI MAY 18 2018

LAZ036-037-048-182030-
St. Helena-East Feliciana-East Baton Rouge-
307 PM CDT FRI MAY 18 2018

...A STRONG THUNDERSTORM WILL AFFECT SOUTHWESTERN ST. HELENA...
SOUTHEASTERN EAST FELICIANA AND NORTHEASTERN EAST BATON ROUGE
PARISHES...

At 307 PM CDT, a strong thunderstorm was located near Clinton, moving
east at 10 mph.

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

Locations impacted include...
Clinton and Darlington.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

LAT...LON 3090 9071 3065 9076 3065 9082 3071 9103
      3089 9100
TIME...MOT...LOC 2007Z 279DEG 9KT 3080 9094

32

Special Weather Statement
National Weather Service New Orleans LA
316 PM CDT FRI MAY 18 2018

LAZ050-182100-
Livingston-
316 PM CDT FRI MAY 18 2018

...A LINE OF STRONG THUNDERSTORMS WILL AFFECT LIVINGSTON PARISH...

At 316 PM CDT, radar indicated strong thunderstorms were located
along a line extending from near Walker to near Port Vincent.
Movement was east at 10 mph.

Winds in excess of 30 mph and dime size hail are possible with these
storms.

Locations impacted include...
Denham Springs, Walker, Livingston, French Settlement, Port Vincent,
Watson and Killian.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

These storms 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 3059 9098 3065 9078 3065 9066 3032 9052
      3030 9056 3029 9057 3032 9084 3035 9087
      3035 9090 3054 9098 3056 9097 3058 9099
TIME...MOT...LOC 2016Z 265DEG 8KT 3054 9090 3041 9084

32

Special Weather Statement
National Weather Service New Orleans LA
324 PM CDT FRI MAY 18 2018

LAZ039-040-071-072-182115-
Washington-Northern Tangipahoa-Southern Tangipahoa-St. Tammany-
324 PM CDT FRI MAY 18 2018

...A LINE OF STRONG THUNDERSTORMS WILL AFFECT NORTHWESTERN ST.
TAMMANY...NORTHEASTERN TANGIPAHOA AND CENTRAL WASHINGTON PARISHES...

At 324 PM CDT, radar indicated strong thunderstorms were located
along a line extending from near Franklinton to near Wilmer. Movement
was southeast at 15 mph.

Winds in excess of 30 mph and half inch hail are possible with these
storms.

Locations impacted include...
Bogalusa, Franklinton, Folsom, Sun, Enon and Wilmer.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

LAT...LON 3074 8983 3072 8983 3070 8985 3070 8984
      3066 8984 3059 9027 3088 9045 3094 9009
TIME...MOT...LOC 2024Z 321DEG 13KT 3088 9012 3085 9033

32

Special Weather Statement
National Weather Service New Orleans LA
338 PM CDT FRI MAY 18 2018

MSZ080-081-182115-
Harrison-Hancock-
338 PM CDT FRI MAY 18 2018

...A STRONG THUNDERSTORM WILL AFFECT SOUTHWESTERN HARRISON AND EAST
CENTRAL HANCOCK COUNTIES...

At 338 PM CDT, a strong thunderstorm was located over Diamondhead,
moving east at 25 mph.

Winds in excess of 30 mph and nickel size hail are possible with this
storm.

Locations impacted include...
Gulfport, Long Beach, Bay St. Louis, Waveland, Diamondhead, Kiln,
Shoreline Park and Gulfport Airport.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

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 3037 8906 3030 8927 3031 8929 3036 8928
      3036 8931 3038 8932 3037 8935 3034 8938
      3034 8934 3032 8932 3027 8938 3032 8949
      3046 8945 3043 8904
TIME...MOT...LOC 2038Z 284DEG 23KT 3038 8940

32

Special Weather Statement
National Weather Service New Orleans LA
342 PM CDT FRI MAY 18 2018

LAZ057-058-060-182115-
St. Charles-St. John The Baptist-St. James-
342 PM CDT FRI MAY 18 2018

...A STRONG THUNDERSTORM WILL AFFECT ST. JOHN THE BAPTIST...
SOUTHEASTERN ST. JAMES AND NORTHWESTERN ST. CHARLES PARISHES...

At 342 PM CDT, a strong thunderstorm was located near Wallace, or
near Reserve, moving east at 5 mph.

Winds in excess of 30 mph and nickel size hail are possible with this
storm.

Locations impacted include...
Reserve, Laplace, Hahnville, Gramercy, Lutcher, Killona, Montz,
Edgard, Garyville, Wallace, Taft, Paradis, North Vacherie, Boutte and
South Vacherie.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

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 2988 9053 2989 9054 2989 9067 3007 9071
      3015 9046 2988 9041
TIME...MOT...LOC 2042Z 259DEG 6KT 3000 9061

32

Special Weather Statement
National Weather Service New Orleans LA
345 PM CDT FRI MAY 18 2018

LAZ061>064-182115-
Orleans-Upper St. Bernard-Upper Plaquemines-Upper Jefferson-
345 PM CDT FRI MAY 18 2018

...A STRONG THUNDERSTORM WILL AFFECT WEST CENTRAL ST. BERNARD...
SOUTHWESTERN ORLEANS...NORTH CENTRAL JEFFERSON AND NORTHWESTERN
PLAQUEMINES PARISHES...

At 345 PM CDT, a strong thunderstorm was located over Arabi, or near
New Orleans, moving southeast at 5 mph.

Winds in excess of 30 mph and nickel size hail are possible with this
storm.

Locations impacted include...
New Orleans, Chalmette, Harvey, Timberlane, Belle Chasse, Marrero,
Gretna, Woodmere, Violet, Terrytown, Meraux, Poydras, Arabi and
Estelle.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

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 2999 9012 3004 9002 3005 8999 2989 8981
      2977 9009
TIME...MOT...LOC 2045Z 335DEG 6KT 2997 9003

32