Severe Thunderstorm Warning 3, NWS New Orleans, LA

544 
WWUS54 KLIX 051720
SVSLIX

Severe Weather Statement
National Weather Service New Orleans LA
1120 AM CST TUE FEB 5 2019

LAC007-057-093-051729-
/O.CAN.KLIX.SV.W.0003.000000T0000Z-190205T1730Z/
St. James LA-Lafourche LA-Assumption LA-
1120 AM CST TUE FEB 5 2019

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN ST. JAMES...
NORTHWESTERN LAFOURCHE AND NORTHEASTERN ASSUMPTION 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 3008 9094 2983 9071 2975 9109 2977 9110
      2981 9110 2984 9114 2986 9115
TIME...MOT...LOC 1719Z 237DEG 18KT 2996 9088 

$$

MJH

Area Forecast Discussion...UPDATED
National Weather Service New Orleans LA
1019 AM CST Tue Feb 5 2019

.UPDATE...
Decided to extend the Dense Fog Advisory through noon for areas
along the MS River and the immediate coast/tidal lakes where sea
fog will persist for much of the day but improve away from the
local influences. Also extended the marine DFA through Wednesday
morning as little change is expected through then, though there
may be brief periods of improvement as convection moves through.
No other changes at this time. 24/RR

&&

.PREV DISCUSSION... /issued 730 AM CST Tue Feb 5 2019/

SOUNDING DISCUSSION...
This morning's sounding was successful/no issues were noted. The
atmosphere is moist and unstable, and has been increasing since
the last 12-24 hours. Temperature/dewpoint has been on an
increase due to strengthening ridge to the east. Fog is currently
occuring and with light winds and saturated sfc, so it may take
some time for it to burn off or not even burn off completely in
some marine areas before the sun sets. Showers are possible today
and some potential for a few thunderstorms. -BL

PREV DISCUSSION... /issued 349 AM CST Tue Feb 5 2019/

DISCUSSION...
A warmer and wetter pattern is expected to be in place through the
first half of the week as an upper ridge builds across the entire
southeastern United States. Moisture levels have already been on the
increase with dewpoints in the lower to mid 60s. Those dewpoints are
several degrees above the nearshore water temps. That combined with
light but consistent southeasterly flow is aiding in the inland
spread of sea fog into the CWA. This will continue through the
morning hours except for locations that see showers. The rain will
cause the fog to dissipate, but only temporarily. Once the showers
exit, a return of reduced visibilities is expected.

All that moisture in place and a weak shortwave moving through has
sparked showers from Natchez to Houma. Morning POPS will be on the
high side to account for current showers. The rest of day will not
be much better but thinking coverage should be more scattered,
similar to the HRRR output. An isolated storm or 2 will be possible
today as well, mainly closer to the coast. The presence of rain and
fog in the morning may slow temps from warming, but by afternoon they
should quickly reach lower to mid 70s. Cloud cover will be
increasing through the overnight period, which is looking like
will be the change needed to mitigate fog development.

The upper level ridge centered south of the area will expand enough
northward Wednesday to cut off rain from the CWA. Temperatures will
respond to the increasing heights by topping out in the upper 70s.
The MAV/MEX even suggests a few locations touching low 80s. Haven't
gone that warm just yet but may need to adjust highs. Did, however,
increase forecast temps above previously used blended models.

A broad trough tracking across the mid section of the country will
send a cold front through the region Thursday night. This will bring
widespread showers and well as much cooler temps. Expect highs and
lows to drop about 20 degrees by Friday and Saturday. They will
begin rebounding late this weekend.

MEFFER

AVIATION...

There won't be a lot of change in conditions day to day until a cold
front gets closer by Thursday or Thursday night. Ceilings vary from
OVC004 to VV001 this morning and should remain that way through at
least noon. Terminals with VV001 could improve to OVC003 by noon or
shortly after but ceilings will remain low through the day. Vis is
all over the place as well and this will improve a little by noon
but should remain at or just under P6SM for all sites through the
day.

MARINE...

Dense sea fog will remain over most marine areas though at least
noon but could stay in all day. A dense fog advisory for all marine
areas will continue through noon but this may be extended if
conditions do not improve. Fog is expected to be back again
overnight. Winds will remain quite low for the next few days until a
cold front moves through the northern gulf possibly by Thursday
night or Friday.

DECISION SUPPORT...
DSS code: Blue.
Deployed: None.
Activation: None.
Activities: River Flood Warnings

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  73  63  77  65 /  70  30  10  10
BTR  75  65  78  65 /  60  30  10  10
ASD  74  61  75  62 /  60  30  10  10
MSY  75  63  75  64 /  50  20  10  10
GPT  70  60  70  60 /  60  30  10  10
PQL  73  60  74  60 /  60  30  10  10

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...Dense Fog Advisory until noon CST today for LAZ040-049-050-057-
     058-060>064-067>070-072.

GM...Dense Fog Advisory until noon CST Wednesday for GMZ530-532-534-
     536-538-550-552-555-557-570-572-575-577.

MS...Dense Fog Advisory until noon CST today for MSZ080.

GM...Dense Fog Advisory until noon CST Wednesday for GMZ532-534-536-
     538-550-552-555-557-570-572-575-577.

&&

Hazardous Weather Outlook
National Weather Service New Orleans LA
351 AM CST Tue Feb 5 2019

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>082-052200-
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-
351 AM CST Tue Feb 5 2019

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

.DAY ONE...Today and Tonight

A Dense Fog Advisory is in effect for all areas through this
morning. Low visibilities will create hazardous driving
conditions. Thickest fog will be near the coasts but visibility
may drop suddenly in more patchy areas.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

A persistent southerly flow will bring gulf moisture over cool
sea and land surfaces through much of the week. These conditions
may produce a dense fog threat each morning through Thursday,
especially in coastal areas.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated.

Special Weather Statement
National Weather Service New Orleans LA
952 AM CST TUE FEB 5 2019

LAZ046-049-056-057-059-051645-
Iberville-Ascension-Assumption-Upper Lafourche-St. James-
952 AM CST TUE FEB 5 2019

...AN AREA OF STRONG THUNDERSTORMS WILL AFFECT SOUTHWESTERN
ASCENSION...SOUTHWESTERN ST. JAMES...SOUTHERN IBERVILLE...
NORTHWESTERN LAFOURCHE AND ASSUMPTION PARISHES...

At 952 AM CST, strong thunderstorms were clustered near
Stephensville, moving northeast at 30 mph.

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

Locations impacted include...
Thibodaux, Donaldsonville, Napoleonville, Supreme, Chackbay,
Paincourtville, Labadieville and Belle Rose.

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

LAT...LON 3000 9124 3003 9122 3015 9098 2984 9074
      2973 9110 2975 9109 2981 9110 2984 9113
      2986 9120 2990 9121 2992 9123 2993 9123
      2997 9126 3000 9126
TIME...MOT...LOC 1552Z 233DEG 25KT 2983 9119

BL