Note:
The expiration time in the watch graphic is amended if the watch is
replaced, cancelled or extended.
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Watch Status Reports.
SEL4
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 74
NWS STORM PREDICTION CENTER NORMAN OK
245 PM CDT SUN MAR 31 2013
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
COASTAL SOUTHWEST LOUISIANA
UPPER AND NORTHERN MIDDLE TEXAS GULF COASTAL PLAIN
COASTAL WATERS
EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 245 PM UNTIL
1000 PM CDT.
HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.
THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 45
STATUTE MILES NORTH AND SOUTH OF A LINE FROM 50 MILES EAST
SOUTHEAST OF LAFAYETTE LOUISIANA TO 60 MILES WEST NORTHWEST OF
ANGLETON TEXAS. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU4).
REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.
OTHER WATCH INFORMATION...CONTINUE...WW 72...WW 73...
DISCUSSION...TSTMS NOW FORMING ALONG W-E FRONT SAGGING SLOWLY S
ACROSS E TX /NEAR BRYAN-COLLEGE STATION/ EXPECTED TO INCREASE IN
COVERAGE/STRENGTH DURING THE NEXT FEW HOURS AS SFC HEATING CONTINUES
S OF BOUNDARY AND AS ASCENT INCREASES WITH CONTINUED EWD MOTION OF
SW TX UPR IMPULSE. STEEP MID LVL LAPSE RATES...FAIRLY RICH LOW-LVL
MOISTURE...AND LARGELY UNIDIRECTIONAL CLOUD-LAYER FLOW ALSO SUGGEST
POTENTIAL FOR HAIL AND POSSIBLY LOCALLY DMGG WIND. WHILE INDIVIDUAL
STORMS SHOULD MOVE MAINLY E OR ESEWD...CONSOLIDATION OF STORM COLD
POOLS MAY SHIFT PROPAGATIONAL COMPONENT OF OVERALL STORM CLUSTER/MCS
MOTION A BIT FARTHER TO THE S. THIS MOTION WOULD CAUSE STORMS TO
IMPACT AREAS S OF EXISTING WWS 72 AND 73 ALONG THE UPR AND NRN
MIDDLE TX GULF CSTL PLN AND SW LA LATER THIS AFTN THROUGH EARLY
TNGT.
AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
MOTION VECTOR 30035.
...CORFIDI
Note:
The Aviation Watch (SAW) product is an approximation to the watch area.
The actual watch is depicted by the shaded areas.
SAW4
WW 74 SEVERE TSTM LA TX CW 311945Z - 010300Z
AXIS..45 STATUTE MILES NORTH AND SOUTH OF LINE..
50ESE LFT/LAFAYETTE LA/ - 60WNW LBX/ANGLETON TX/
..AVIATION COORDS.. 40NM N/S /34S BTR - 42N PSX/
HAIL SURFACE AND ALOFT..1.5 INCHES. WIND GUSTS..60 KNOTS.
MAX TOPS TO 500. MEAN STORM MOTION VECTOR 30035.
LAT...LON 29279120 28799638 30109638 30569120
THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU4.
Watch 74 Status Report Messages:
STATUS REPORT #4 ON WW 74
VALID 010025Z - 010140Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 60 S CLL TO
15 WNW GLS TO 25 WSW HUM.
..COHEN..04/01/13
ATTN...WFO...LCH...HGX...
&&
STATUS REPORT FOR WS 74
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
TXC039-089-157-167-481-010140-
TX
. TEXAS COUNTIES INCLUDED ARE
BRAZORIA COLORADO FORT BEND
GALVESTON WHARTON
$$
GMZ355-450-452-455-010140-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
COASTAL WATERS FROM HIGH ISLAND TO FREEPORT TX OUT 20 NM
COASTAL WATERS FROM CAMERON LA TO HIGH ISLAND TX OUT 20 NM
COASTAL WATERS FROM INTRACOASTAL CITY TO CAMERON LA OUT 20 NM
COASTAL WATERS FROM LOWER ATCHAFALAYA RIVER TO INTRACOASTAL CITY
LA OUT 20 NM
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #3 ON WW 74
VALID 312330Z - 010040Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 60 S CLL TO
35 NW HUM.
FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 359
..COHEN..03/31/13
ATTN...WFO...LCH...HGX...
&&
STATUS REPORT FOR WS 74
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
LAC023-101-113-010040-
LA
. LOUISIANA PARISHES INCLUDED ARE
CAMERON ST. MARY VERMILION
$$
TXC039-071-089-157-167-201-245-481-010040-
TX
. TEXAS COUNTIES INCLUDED ARE
BRAZORIA CHAMBERS COLORADO
FORT BEND GALVESTON HARRIS
JEFFERSON WHARTON
$$
GMZ335-355-430-432-435-450-452-455-010040-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
GALVESTON BAY
COASTAL WATERS FROM HIGH ISLAND TO FREEPORT TX OUT 20 NM
SABINE LAKE
CALCASIEU LAKE
VERMILION BAY
COASTAL WATERS FROM CAMERON LA TO HIGH ISLAND TX OUT 20 NM
COASTAL WATERS FROM INTRACOASTAL CITY TO CAMERON LA OUT 20 NM
COASTAL WATERS FROM LOWER ATCHAFALAYA RIVER TO INTRACOASTAL CITY
LA OUT 20 NM
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #2 ON WW 74
VALID 312225Z - 312340Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 55 S CLL TO
25 W 7R4 TO 35 NW HUM.
..COHEN..03/31/13
ATTN...WFO...LCH...HGX...
&&
STATUS REPORT FOR WS 74
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
LAC023-101-113-312340-
LA
. LOUISIANA PARISHES INCLUDED ARE
CAMERON ST. MARY VERMILION
$$
TXC039-071-089-157-167-201-245-481-312340-
TX
. TEXAS COUNTIES INCLUDED ARE
BRAZORIA CHAMBERS COLORADO
FORT BEND GALVESTON HARRIS
JEFFERSON WHARTON
$$
GMZ335-355-430-432-435-450-452-455-312340-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
GALVESTON BAY
COASTAL WATERS FROM HIGH ISLAND TO FREEPORT TX OUT 20 NM
SABINE LAKE
CALCASIEU LAKE
VERMILION BAY
COASTAL WATERS FROM CAMERON LA TO HIGH ISLAND TX OUT 20 NM
COASTAL WATERS FROM INTRACOASTAL CITY TO CAMERON LA OUT 20 NM
COASTAL WATERS FROM LOWER ATCHAFALAYA RIVER TO INTRACOASTAL CITY
LA OUT 20 NM
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #1 ON WW 74
VALID 312135Z - 312240Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 NW BPT TO
25 NE BPT TO 20 S BTR.
..COHEN..03/31/13
ATTN...WFO...LCH...HGX...
&&
STATUS REPORT FOR WS 74
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
LAC023-045-101-113-312240-
LA
. LOUISIANA PARISHES INCLUDED ARE
CAMERON IBERIA ST. MARY
VERMILION
$$
TXC039-071-089-157-167-201-245-291-361-481-312240-
TX
. TEXAS COUNTIES INCLUDED ARE
BRAZORIA CHAMBERS COLORADO
FORT BEND GALVESTON HARRIS
JEFFERSON LIBERTY ORANGE
WHARTON
$$
GMZ335-355-430-432-435-450-452-455-312240-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
GALVESTON BAY
COASTAL WATERS FROM HIGH ISLAND TO FREEPORT TX OUT 20 NM
SABINE LAKE
CALCASIEU LAKE
VERMILION BAY
COASTAL WATERS FROM CAMERON LA TO HIGH ISLAND TX OUT 20 NM
COASTAL WATERS FROM INTRACOASTAL CITY TO CAMERON LA OUT 20 NM
COASTAL WATERS FROM LOWER ATCHAFALAYA RIVER TO INTRACOASTAL CITY
LA OUT 20 NM
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
Note:
Click for Complete Product Text.
Tornadoes
Probability of 2 or more tornadoes
|
Low (20%)
|
Probability of 1 or more strong (F2-F5) tornadoes
|
Low (5%)
|
Wind
Probability of 10 or more severe wind events
|
High (80%)
|
Probability of 1 or more wind events > 65 knots
|
Mod (30%)
|
Hail
Probability of 10 or more severe hail events
|
High (70%)
|
Probability
of 1 or
more hailstones > 2 inches
|
Low (20%)
|
Combined Severe Hail/Wind
Probability of 6 or more combined severe hail/wind events
|
High (>95%)
|
For each watch, probabilities for particular events inside the watch
(listed above in each table) are determined by the issuing forecaster.
The "Low" category contains probability values ranging from less than 2%
to 20% (F2-F5 tornadoes), less than 5% to 20% (all other probabilities),
"Moderate" from 30% to 60%, and "High" from 70% to greater than 95%.
High values are bolded and lighter in color to provide awareness of
an increased threat for a particular event.