National Hurricane Center (NHC) Atlantic Map

The NHC has issued its final advisory on this system. Public Advisories from the Weather Prediction Center will provide updates as long as the system remains a flood threat. Issued at 400 AM CDT Fri Sep 17 2021

Storm Surge Watch/Warning Map last updated Tue, 14 Sep 2021 17:53:37 GMT

5-Day Uncertainty Track last updated Tue, 14 Sep 2021 17:52:19 GMT


Wind Speed Probabilities last updated Tue, 14 Sep 2021 15:22:36 GMT

Issued at 100 PM CDT Tue Sep 14 2021 000 WTNT34 KNHC 141751 TCPAT4 BULLETIN Tropical Storm Nicholas Intermediate Advisory Number 10A NWS National Hurricane Center Miami FL AL142021 100 PM CDT Tue Sep 14 2021 ...NICHOLAS MOVING SLOWLY EAST-NORTHEASTWARD ACROSS SOUTHERN PORTIONS OF THE HOUSTON METROPOLITAN AREA... ...LIFE-THREATENING FLASH FLOODS EXPECTED ACROSS PORTIONS OF THE DEEP SOUTH DURING THE NEXT COUPLE OF DAYS... SUMMARY OF 100 PM CDT...1800 UTC...INFORMATION ---------------------------------------------- LOCATION...29.4N 95.0W ABOUT 30 MI...55 KM SE OF HOUSTON TEXAS ABOUT 60 MI...95 KM WSW OF PORT ARTHUR TEXAS MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H PRESENT MOVEMENT...ENE OR 75 DEGREES AT 7 MPH...11 KM/H MINIMUM CENTRAL PRESSURE...1003 MB...29.62 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: The Storm Surge Warning has been discontinued west of High Island including Galveston Bay. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Storm Surge Warning is in effect for... * High Island Texas to Sabine Pass A Tropical Storm Warning is in effect for... * High Island Texas to Cameron Louisiana A Storm Surge Watch is in effect for... * Sabine Pass to Cameron Louisiana A Storm Surge Warning means there is a danger of life-threatening inundation, from rising water moving inland from the coastline. For a depiction of areas at risk, please see the National Weather Service Storm Surge Watch/Warning Graphic, available at hurricanes.gov. This is a life-threatening situation. Persons located within these areas should take all necessary actions to protect life and property from rising water and the potential for other dangerous conditions. Promptly follow evacuation and other instructions from local officials. A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area. A Storm Surge Watch means there is a possibility of life-threatening inundation, from rising water moving inland from the coastline. For a depiction of areas at risk, please see the National Weather Service Storm Surge Watch/Warning Graphic, available at hurricanes.gov. For storm information specific to your area, including possible inland watches and warnings, please monitor products issued by your local National Weather Service forecast office. DISCUSSION AND OUTLOOK ---------------------- At 100 PM CDT (1800 UTC), the center of Tropical Storm Nicholas was located near latitude 29.4 North, longitude 95.0 West. Nicholas is moving toward the east-northeast near 7 mph (11 km/h) and this general motion should continue through tonight. An eastward turn is expected over Louisiana by Wednesday. Little motion is anticipated on Thursday. NOAA Doppler weather radar and surface observations indicate that maximum sustained winds have decreased to near 40 mph (65 km/h) with higher gusts. Additional weakening is forecast during the next couple of days, and the storm is forecast to become a tropical depression by tonight. Tropical-storm-force winds extend outward up to 140 miles (220 km), mainly over water to the southeast of the center. A TCOON observing station at Texas Point, Sabine Pass, Texas, recently measured a 1-minute sustained wind of 40 mph (65 km/h) and a gust to 53 mph (85 km/h) while a NOAA Ocean Service observing station at Calcasieu Pass, Louisiana, recently reported a 1-minute sustained wind of 39 mph (63 km/h) and a gust to 47 mph (76 km/h). The estimated minimum central pressure is 1003 mb (29.62 inches) based on nearby surface observations. HAZARDS AFFECTING LAND ---------------------- Key messages for Nicholas can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDAT4, WMO header WTNT44 KNHC and on the web at hurricanes.gov/graphics_at4.shtml?key_messages RAINFALL: Nicholas is expected to produce additional rainfall of 5 to 10 inches from the upper Texas coastal area into central to southern Louisiana, far southern Mississippi, far southern Alabama and the western Florida Panhandle through Thursday, with isolated storm totals of 20 inches across southern Louisiana. Life-threatening flash flooding impacts, especially in urbanized metropolitan areas, are possible across these regions. Widespread minor to isolated major river flooding is expected across portions of the upper Texas Gulf Coast and southern Louisiana and Mississippi. For the latest rainfall reports and wind gusts associated with Hurricane Nicholas see the companion storm summary at WBCSCCNS4 with the WMO header ACUS44KWBC or at the following link https://www.wpc.ncep.noaa.gov/discussions/nfdscc4.html STORM SURGE: The combination of a dangerous storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline. The water could reach the following heights above ground somewhere in the indicated areas if the peak surge occurs at the time of high tide... High Island, TX to Cameron, LA...2-4 ft San Luis Pass to High Island, TX...1-3 ft Galveston Bay...1-3 ft Cameron, LA to Intracoastal City, LA...1-3 ft Sabine Lake and Calcasieu Lake...1-3 ft The deepest water will occur along the immediate coast in areas of onshore winds, where the surge will be accompanied by large and dangerous waves. Surge-related flooding depends on the relative timing of the surge and the tidal cycle, and can vary greatly over short distances. For information specific to your area, please see products issued by your local National Weather Service forecast office. WIND: Tropical storm conditions are expected to continue along the Louisiana coast into this afternoon. Tropical storm conditions in the warning area across the upper Texas coast will diminish this afternoon as Nicholas moves farther to the east. TORNADOES: A tornado or two will be possible today into tonight across southern Louisiana. SURF: Swells generated by Nicholas will continue affecting portions of the northwest Gulf coast today. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. NEXT ADVISORY ------------- Next complete advisory at 400 PM CDT. $$ Forecaster Stewart

...NICHOLAS MOVING SLOWLY EAST-NORTHEASTWARD ACROSS SOUTHERN PORTIONS OF THE HOUSTON METROPOLITAN AREA... ...LIFE-THREATENING FLASH FLOODS EXPECTED ACROSS PORTIONS OF THE DEEP SOUTH DURING THE NEXT COUPLE OF DAYS... As of 1:00 PM CDT Tue Sep 14 the center of Nicholas was located near 29.4, -95.0 with movement ENE at 7 mph. The minimum central pressure was 1003 mb with maximum sustained winds of about 40 mph.

000
ABNT20 KNHC 141742
TWOAT

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Tue Sep 14 2021

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

The National Hurricane Center is issuing advisories on Tropical
Storm Nicholas, located over the upper Texas coastal plain near
Houston.

Showers and thunderstorms associated with a low pressure area
located a few hundred miles south-southeast of the Cabo Verde
Islands continues to show signs of organization. Environmental
conditions are expected to remain conducive for development, and a
tropical depression is likely to form during the next couple of
days while system moves generally westward at about 15 mph across
the eastern tropical Atlantic Ocean.
* Formation chance through 48 hours...high...70 percent.
* Formation chance through 5 days...high...90 percent.

A trough of low pressure located a couple of hundred miles
northeast of the southeastern Bahamas is producing a large area
of disorganized showers and thunderstorms. Environmental
conditions are forecast to be conducive for gradual development
during the next few days, and a tropical depression could form
while the system moves north-northwestward to northward across the
western Atlantic.
* Formation chance through 48 hours...medium...40 percent.
* Formation chance through 5 days...medium...60 percent.

$$
Forecaster Brown

Potential Storm Surge Flooding Map last updated Tue, 14 Sep 2021 15:41:09 GMT

Issued at 1000 AM CDT Tue Sep 14 2021 000 WTNT44 KNHC 141457 TCDAT4 Tropical Storm Nicholas Discussion Number 10 NWS National Hurricane Center Miami FL AL142021 1000 AM CDT Tue Sep 14 2021 Doppler weather radar data from Houston and Lake Charles, along with surface observations, indicate that Nicholas has continued to weaken while moving farther inland. The strongest winds recently reported near the Texas and Louisiana coasts have been 33-35 kt at a TCOON observing station near Sabine Pass, Texas. The strongest winds over water south of southwestern Louisiana are based on Doppler radar average velocities of 45-50 kt between 5000-7500 ft. Based on these wind data, the initial intensity has been lowered to 40 kt. The estimated central pressure of 1002 mb is based on nearby surface observations in the Houston metropolitan area. Further weakening is expected as Nicholas moves farther inland due to frictional effects, entrainment of very dry mid-level air from the southern Plains, and increasing southwesterly to westerly shear. The latter condition is expected to cause the low- and upper-level circulation to decouple in about 24 hours, which will hasten the weakening process. No significant changes were made to the previous intensity forecast, and Nicholas is now expected to become a tropical depression by tonight and degenerate into a remnant low by late Wednesday. Nicholas is now moving northeastward or 050 degrees at a slower forward speed of 5 kt. The cyclone should gradually turn toward the east-northeast by tonight, and move eastward more slowly on Wednesday and Thursday. It is possible that Nicholas could stall over southwestern or central Louisiana as the low-level steering flow collapses. The new NHC track forecast is similar to but slightly slower than the previous advisory tack. Although the winds associated with Nicholas will be weakening, heavy rainfall and a significant flash flood risk will continue along the Gulf Coast during the next couple of days. Key Messages: 1. Heavy rainfall will impact areas from the upper coast of Texas, across Louisiana, southern Mississippi, far southern Alabama and the western Florida Panhandle through Thursday. Significant rainfall amounts are expected, potentially resulting in areas of life-threatening flash and urban flooding across these areas. Minor to isolated major river flooding is also possible in smaller river basins and urban areas. 2. There is the danger of life-threatening storm surge inundation along the coast of Texas from Port Bolivar to Sabine Pass. Residents in these areas should follow any advice given by local officials. 3. Tropical storm conditions are expected to continue along the Louisiana coast into this afternoon. Tropical storm conditions in the warning area across the upper Texas coast will diminish this afternoon as Nicholas moves farther to the northeast. FORECAST POSITIONS AND MAX WINDS INIT 14/1500Z 29.6N 95.3W 40 KT 45 MPH...INLAND 12H 15/0000Z 30.1N 94.7W 30 KT 35 MPH...INLAND 24H 15/1200Z 30.4N 93.9W 25 KT 30 MPH...INLAND 36H 16/0000Z 30.4N 93.2W 25 KT 30 MPH...INLAND 48H 16/1200Z 30.5N 92.8W 15 KT 15 MPH...INLAND 60H 17/0000Z 30.9N 92.8W 15 KT 15 MPH...POST-TROP/REMNT LOW 72H 17/1200Z...DISSIPATED $$ Forecaster Stewart

Issued at 1500 UTC TUE SEP 14 2021 000 FONT14 KNHC 141452 PWSAT4 TROPICAL STORM NICHOLAS WIND SPEED PROBABILITIES NUMBER 10 NWS NATIONAL HURRICANE CENTER MIAMI FL AL142021 1500 UTC TUE SEP 14 2021 AT 1500Z THE CENTER OF TROPICAL STORM NICHOLAS WAS LOCATED NEAR LATITUDE 29.6 NORTH...LONGITUDE 95.3 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 40 KTS...45 MPH...75 KM/H. Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH) ATLANTIC STANDARD TIME (AST)...SUBTRACT 4 HOURS FROM Z TIME EASTERN DAYLIGHT TIME (EDT)...SUBTRACT 4 HOURS FROM Z TIME CENTRAL DAYLIGHT TIME (CDT)...SUBTRACT 5 HOURS FROM Z TIME WIND SPEED PROBABILITY TABLE FOR SPECIFIC LOCATIONS CHANCES OF SUSTAINED (1-MINUTE AVERAGE) WIND SPEEDS OF AT LEAST ...34 KT (39 MPH... 63 KM/H)... ...50 KT (58 MPH... 93 KM/H)... ...64 KT (74 MPH...119 KM/H)... FOR LOCATIONS AND TIME PERIODS DURING THE NEXT 5 DAYS PROBABILITIES FOR LOCATIONS ARE GIVEN AS OP(CP) WHERE OP IS THE PROBABILITY OF THE EVENT BEGINNING DURING AN INDIVIDUAL TIME PERIOD (ONSET PROBABILITY) (CP) IS THE PROBABILITY OF THE EVENT OCCURRING BETWEEN 12Z TUE AND THE FORECAST HOUR (CUMULATIVE PROBABILITY) PROBABILITIES ARE GIVEN IN PERCENT X INDICATES PROBABILITIES LESS THAN 1 PERCENT PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT. PROBABILITIES FOR 34...50...64 KT SHOWN WHEN THE 5-DAY 64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT. - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - - FROM FROM FROM FROM FROM FROM FROM TIME 12Z TUE 00Z WED 12Z WED 00Z THU 12Z THU 12Z FRI 12Z SAT PERIODS TO TO TO TO TO TO TO 00Z WED 12Z WED 00Z THU 12Z THU 12Z FRI 12Z SAT 12Z SUN FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT BATON ROUGE LA 34 X 1( 1) 2( 3) 1( 4) 1( 5) X( 5) X( 5) MORGAN CITY LA 34 X 1( 1) 2( 3) 1( 4) X( 4) X( 4) X( 4) ALEXANDRIA LA 34 1 1( 2) 3( 5) 1( 6) 1( 7) X( 7) X( 7) LAFAYETTE LA 34 1 2( 3) 4( 7) 1( 8) X( 8) X( 8) X( 8) NEW IBERIA LA 34 X 2( 2) 4( 6) 1( 7) X( 7) X( 7) X( 7) GFMX 280N 930W 34 1 X( 1) 1( 2) 1( 3) X( 3) X( 3) X( 3) SHREVEPORT LA 34 X 1( 1) 1( 2) X( 2) 1( 3) X( 3) X( 3) FORT POLK LA 34 3 5( 8) 3(11) X(11) 1(12) X(12) X(12) LAKE CHARLES 34 7 7(14) 4(18) X(18) X(18) X(18) X(18) LAKE CHARLES 50 X 2( 2) 1( 3) X( 3) X( 3) X( 3) X( 3) CAMERON LA 34 8 6(14) 3(17) X(17) X(17) X(17) X(17) CAMERON LA 50 X 1( 1) 1( 2) 1( 3) X( 3) X( 3) X( 3) JASPER TX 34 9 4(13) 2(15) X(15) 1(16) X(16) X(16) JASPER TX 50 1 1( 2) X( 2) X( 2) 1( 3) X( 3) X( 3) KOUNTZE TX 34 99 X(99) X(99) X(99) X(99) X(99) X(99) KOUNTZE TX 50 1 1( 2) X( 2) X( 2) 1( 3) X( 3) X( 3) PORT ARTHUR TX 34 99 X(99) X(99) X(99) X(99) X(99) X(99) PORT ARTHUR TX 50 1 1( 2) 1( 3) X( 3) X( 3) X( 3) X( 3) GALVESTON TX 34 99 X(99) X(99) X(99) X(99) X(99) X(99) GALVESTON TX 50 99 X(99) X(99) X(99) X(99) X(99) X(99) HOUSTON TX 34 99 X(99) X(99) X(99) X(99) X(99) X(99) HOUSTON TX 50 99 X(99) X(99) X(99) X(99) X(99) X(99) FREEPORT TX 34 99 X(99) X(99) X(99) X(99) X(99) X(99) FREEPORT TX 50 99 X(99) X(99) X(99) X(99) X(99) X(99) HIGH ISLAND TX 34 99 X(99) X(99) X(99) X(99) X(99) X(99) HIGH ISLAND TX 50 99 X(99) X(99) X(99) X(99) X(99) X(99) $$ FORECASTER STEWART

Issued at 1500 UTC TUE SEP 14 2021 000 WTNT24 KNHC 141451 TCMAT4 TROPICAL STORM NICHOLAS FORECAST/ADVISORY NUMBER 10 NWS NATIONAL HURRICANE CENTER MIAMI FL AL142021 1500 UTC TUE SEP 14 2021 CHANGES IN WATCHES AND WARNINGS WITH THIS ADVISORY... THE TROPICAL STORM WARNING HAS BEEN DISCONTINUED WEST OF HIGH ISLAND...TEXAS. THE STORM SURGE WARNING HAS BEEN DISCONTINUED SOUTH OF PORT BOLIVAR...TEXAS. THE STORM SURGE WATCH HAS BEEN DISCONTINUED EAST OF CAMERON... LOUISIANA. SUMMARY OF WATCHES AND WARNINGS IN EFFECT... A STORM SURGE WARNING IS IN EFFECT FOR... * PORT BOLIVAR TEXAS TO SABINE PASS INCLUDING GALVESTON BAY A TROPICAL STORM WARNING IS IN EFFECT FOR... * HIGH ISLAND TEXAS TO CAMERON LOUISIANA A STORM SURGE WATCH IS IN EFFECT FOR... * SABINE PASS TO CAMERON LOUISIANA A STORM SURGE WARNING MEANS THERE IS A DANGER OF LIFE-THREATENING INUNDATION...FROM RISING WATER MOVING INLAND FROM THE COASTLINE. FOR A DEPICTION OF AREAS AT RISK...PLEASE SEE THE NATIONAL WEATHER SERVICE STORM SURGE WATCH/WARNING GRAPHIC...AVAILABLE AT HURRICANES.GOV. THIS IS A LIFE-THREATENING SITUATION. PERSONS LOCATED WITHIN THESE AREAS SHOULD TAKE ALL NECESSARY ACTIONS TO PROTECT LIFE AND PROPERTY FROM RISING WATER AND THE POTENTIAL FOR OTHER DANGEROUS CONDITIONS. PROMPTLY FOLLOW EVACUATION AND OTHER INSTRUCTIONS FROM LOCAL OFFICIALS. A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE EXPECTED SOMEWHERE WITHIN THE WARNING AREA. A STORM SURGE WATCH MEANS THERE IS A POSSIBILITY OF LIFE-THREATENING INUNDATION...FROM RISING WATER MOVING INLAND FROM THE COASTLINE. FOR A DEPICTION OF AREAS AT RISK...PLEASE SEE THE NATIONAL WEATHER SERVICE STORM SURGE WATCH/WARNING GRAPHIC...AVAILABLE AT HURRICANES.GOV. TROPICAL STORM CENTER LOCATED NEAR 29.6N 95.3W AT 14/1500Z POSITION ACCURATE WITHIN 20 NM PRESENT MOVEMENT TOWARD THE NORTHEAST OR 40 DEGREES AT 5 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1002 MB MAX SUSTAINED WINDS 40 KT WITH GUSTS TO 50 KT. 34 KT.......120NE 120SE 0SW 30NW. 12 FT SEAS.. 0NE 60SE 0SW 0NW. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT. REPEAT...CENTER LOCATED NEAR 29.6N 95.3W AT 14/1500Z AT 14/1200Z CENTER WAS LOCATED NEAR 29.4N 95.5W FORECAST VALID 15/0000Z 30.1N 94.7W...INLAND MAX WIND 30 KT...GUSTS 40 KT. FORECAST VALID 15/1200Z 30.4N 93.9W...INLAND MAX WIND 25 KT...GUSTS 35 KT. FORECAST VALID 16/0000Z 30.4N 93.2W...INLAND MAX WIND 25 KT...GUSTS 35 KT. FORECAST VALID 16/1200Z 30.5N 92.8W...INLAND MAX WIND 15 KT...GUSTS 20 KT. FORECAST VALID 17/0000Z 30.9N 92.8W...POST-TROP/REMNT LOW MAX WIND 15 KT...GUSTS 20 KT. FORECAST VALID 17/1200Z...DISSIPATED REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 29.6N 95.3W INTERMEDIATE PUBLIC ADVISORY...WTNT34 KNHC/MIATCPAT4...AT 14/1800Z NEXT ADVISORY AT 14/2100Z $$ FORECASTER STEWART

Storm Surge Watch/Warning Map last updated Mon, 13 Sep 2021 14:37:31 GMT

5-Day Uncertainty Track last updated Mon, 13 Sep 2021 14:37:22 GMT


Wind Speed Probabilities last updated Mon, 13 Sep 2021 14:37:22 GMT

Issued at 1000 AM CDT Mon Sep 13 2021 000 WTNT44 KNHC 131436 TCDAT4 Tropical Storm Nicholas Discussion Number 6 NWS National Hurricane Center Miami FL AL142021 1000 AM CDT Mon Sep 13 2021 Doppler radar data from Brownsville and Corpus Christi, Texas, along with reconnaissance aircraft flight-level wind data, indicate that Nicholas' inner-core structure has undergone some radical changes since the previous advisory. The earlier near-eyewall pattern dissipated a few hours ago, and has been replaced with what appears to be an ongoing reformation of a new center abut 90 nmi north-northeast of the old center. The aircraft recently found a pressure of 1000 to 1002 mb with the dissipating original center, while Doppler radar velocity data show a pronounced mid- to upper-level circulation forming farther north as previously mentioned. The Air Force Reserve Hurricane Hunter aircraft is going to be concentrating its reconnoiter mission in Nicholas' northeastern quadrant to see if reformation of the low-level center is occurring beneath the mid-level circulation noted in radar data. The initial wind speed remains 50 kt based on recent aircraft 850-mb flight-level winds of 59 kt, which equates to about 47 kt equivalent surface winds. The initial motion is an uncertain 005/10 kt due to the erosion and ongoing reformation of the center. Despite the recent inner-core erosion, the latest NHC model guidance remains in fairly good agreement on Nicholas moving northward through a weakness in the subtropical ridge. The GFS model has been performing exceptionally well with predicting the recent erosion and more northward reformation of the Nicholas' center. The new NHC track forecast is similar to but slightly east or right of the previous advisory track, and lies along the eastern edge of the track consensus model envelope, which is to the left of the GFS track prediction. Although the inner-core convective pattern has been disrupted, recent trends in the radar data suggest that a new center should reform farther northeast into the convective cloud shield. The latest GFS- and ECMWF-based SHIPS shear analyses indicate that westerly shear of near 20 kt is allegedly affecting Nicholas. However, water vapor satellite imagery suggests that the upper-level shear vector is actually from a south-southwesterly direction, which is more along than across the cyclone's forward motion, thus reducing the magnitude and negative effects of the vertical wind shear. Therefore, strengthening is still expected until landfall as Nicholas continues to move over slightly warmer Gulf waters. It is possible that Nicholas could become a hurricane just before landfall, and that's the reason for the northeastward extension of the hurricane watch area. Nicholas should rapidly weaken after landfall due to increased frictional effects, strong southwesterly shear, and entrainment of mid-level dry air, resulting in degeneration into a tropical depression by late Tuesday and a remnant low on Wednesday. Otherwise, no significant changes were made to the previous advisory intensity forecast. Key Messages: 1. Heavy rainfall will impact portions of the Texas and Louisiana coasts through the middle of the week. Significant rainfall amounts are possible, potentially resulting in areas of life-threatening flash and urban flooding, especially in highly urbanized metropolitan areas. Minor to isolated moderate river flooding is also expected. 2. There is the danger of life-threatening storm surge inundation along the coast of Texas from Port Aransas to Sabine Pass. Residents in these areas should follow any advice given by local officials. 3. Nicholas is forecast to approach the middle Texas coast as a strong tropical storm by this evening, and could be near hurricane intensity at landfall. Tropical storm conditions are expected along portions of the middle Texas coast beginning this afternoon, with hurricane conditions possible from Port Aransas to San Luis Pass by late afternoon through tonight. 4. Tropical storm conditions are expected along portions of the coast of south Texas into the afternoon. FORECAST POSITIONS AND MAX WINDS INIT 13/1500Z 26.4N 96.8W 50 KT 60 MPH 12H 14/0000Z 27.5N 96.7W 60 KT 70 MPH 24H 14/1200Z 29.1N 96.3W 45 KT 50 MPH...INLAND 36H 15/0000Z 30.2N 95.4W 30 KT 35 MPH...INLAND 48H 15/1200Z 31.0N 94.0W 25 KT 30 MPH...INLAND 60H 16/0000Z 31.5N 92.5W 20 KT 25 MPH...INLAND 72H 16/1200Z 32.0N 91.1W 20 KT 25 MPH...POST-TROP/REMNT LOW 96H 17/1200Z...DISSIPATED $$ Forecaster Stewart

Issued at 1500 UTC MON SEP 13 2021 000 FONT14 KNHC 131435 PWSAT4 TROPICAL STORM NICHOLAS WIND SPEED PROBABILITIES NUMBER 6 NWS NATIONAL HURRICANE CENTER MIAMI FL AL142021 1500 UTC MON SEP 13 2021 AT 1500Z THE CENTER OF TROPICAL STORM NICHOLAS WAS LOCATED NEAR LATITUDE 26.4 NORTH...LONGITUDE 96.8 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 50 KTS...60 MPH...95 KM/H. Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH) ATLANTIC STANDARD TIME (AST)...SUBTRACT 4 HOURS FROM Z TIME EASTERN DAYLIGHT TIME (EDT)...SUBTRACT 4 HOURS FROM Z TIME CENTRAL DAYLIGHT TIME (CDT)...SUBTRACT 5 HOURS FROM Z TIME WIND SPEED PROBABILITY TABLE FOR SPECIFIC LOCATIONS CHANCES OF SUSTAINED (1-MINUTE AVERAGE) WIND SPEEDS OF AT LEAST ...34 KT (39 MPH... 63 KM/H)... ...50 KT (58 MPH... 93 KM/H)... ...64 KT (74 MPH...119 KM/H)... FOR LOCATIONS AND TIME PERIODS DURING THE NEXT 5 DAYS PROBABILITIES FOR LOCATIONS ARE GIVEN AS OP(CP) WHERE OP IS THE PROBABILITY OF THE EVENT BEGINNING DURING AN INDIVIDUAL TIME PERIOD (ONSET PROBABILITY) (CP) IS THE PROBABILITY OF THE EVENT OCCURRING BETWEEN 12Z MON AND THE FORECAST HOUR (CUMULATIVE PROBABILITY) PROBABILITIES ARE GIVEN IN PERCENT X INDICATES PROBABILITIES LESS THAN 1 PERCENT PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT. PROBABILITIES FOR 34...50...64 KT SHOWN WHEN THE 5-DAY 64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT. - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - - FROM FROM FROM FROM FROM FROM FROM TIME 12Z MON 00Z TUE 12Z TUE 00Z WED 12Z WED 12Z THU 12Z FRI PERIODS TO TO TO TO TO TO TO 00Z TUE 12Z TUE 00Z WED 12Z WED 12Z THU 12Z FRI 12Z SAT FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT JACKSON MS 34 X X( X) X( X) 1( 1) 2( 3) X( 3) X( 3) NEW ORLEANS LA 34 X X( X) 1( 1) X( 1) 2( 3) X( 3) X( 3) GFMX 280N 910W 34 1 2( 3) 1( 4) X( 4) 1( 5) X( 5) X( 5) BATON ROUGE LA 34 X 1( 1) 1( 2) 1( 3) 2( 5) X( 5) X( 5) MORGAN CITY LA 34 X 2( 2) 1( 3) 1( 4) 1( 5) X( 5) X( 5) ALEXANDRIA LA 34 X 3( 3) 1( 4) 3( 7) 3(10) X(10) X(10) LAFAYETTE LA 34 X 4( 4) X( 4) 2( 6) 2( 8) X( 8) X( 8) NEW IBERIA LA 34 X 4( 4) X( 4) 2( 6) 1( 7) X( 7) X( 7) GFMX 280N 930W 34 4 5( 9) 1(10) 1(11) 1(12) X(12) X(12) SHREVEPORT LA 34 X 2( 2) 1( 3) 1( 4) 2( 6) X( 6) X( 6) FORT POLK LA 34 X 5( 5) 2( 7) 5(12) 1(13) X(13) X(13) LAKE CHARLES 34 1 6( 7) 3(10) 3(13) 1(14) X(14) X(14) CAMERON LA 34 3 8(11) 4(15) 2(17) 1(18) X(18) X(18) JASPER TX 34 1 7( 8) 6(14) 3(17) 1(18) X(18) X(18) KOUNTZE TX 34 1 12(13) 9(22) 3(25) 1(26) X(26) X(26) PORT ARTHUR TX 34 1 12(13) 7(20) 3(23) 1(24) X(24) X(24) GALVESTON TX 34 14 30(44) 4(48) X(48) X(48) X(48) X(48) GALVESTON TX 50 X 3( 3) 3( 6) X( 6) X( 6) X( 6) X( 6) HOUSTON TX 34 2 42(44) 10(54) 1(55) X(55) X(55) X(55) HOUSTON TX 50 X 4( 4) 3( 7) X( 7) X( 7) X( 7) X( 7) AUSTIN TX 34 1 4( 5) 1( 6) X( 6) X( 6) X( 6) X( 6) SAN ANTONIO TX 34 1 3( 4) X( 4) 1( 5) X( 5) X( 5) X( 5) FREEPORT TX 34 13 54(67) 2(69) X(69) X(69) X(69) X(69) FREEPORT TX 50 X 7( 7) 1( 8) X( 8) X( 8) X( 8) X( 8) FREEPORT TX 64 X 1( 1) X( 1) X( 1) X( 1) X( 1) X( 1) GFMX 280N 950W 34 58 6(64) 1(65) X(65) X(65) X(65) X(65) GFMX 280N 950W 50 2 3( 5) X( 5) X( 5) X( 5) X( 5) X( 5) HIGH ISLAND TX 34 2 20(22) 8(30) 1(31) 1(32) X(32) X(32) MATAGORDA TX 34 61 26(87) 1(88) X(88) X(88) X(88) X(88) MATAGORDA TX 50 2 28(30) 1(31) X(31) X(31) X(31) X(31) MATAGORDA TX 64 X 3( 3) X( 3) X( 3) X( 3) X( 3) X( 3) PORT O CONNOR 34 75 15(90) X(90) X(90) X(90) X(90) X(90) PORT O CONNOR 50 12 36(48) 1(49) X(49) X(49) X(49) X(49) PORT O CONNOR 64 X 5( 5) X( 5) X( 5) X( 5) X( 5) X( 5) ROCKPORT TX 34 42 12(54) X(54) X(54) X(54) X(54) X(54) ROCKPORT TX 50 6 11(17) X(17) X(17) X(17) X(17) X(17) CORPUS CHRISTI 34 13 10(23) 1(24) X(24) X(24) X(24) X(24) CORPUS CHRISTI 50 1 5( 6) X( 6) X( 6) X( 6) X( 6) X( 6) GFMX 270N 960W 34 97 X(97) X(97) X(97) X(97) X(97) X(97) GFMX 270N 960W 50 14 1(15) X(15) X(15) X(15) X(15) X(15) MCALLEN TX 34 1 2( 3) X( 3) X( 3) X( 3) X( 3) X( 3) HARLINGEN TX 34 1 3( 4) X( 4) X( 4) X( 4) X( 4) X( 4) BROWNSVILLE TX 34 2 3( 5) X( 5) X( 5) X( 5) X( 5) X( 5) GFMX 250N 960W 34 99 X(99) X(99) X(99) X(99) X(99) X(99) $$ FORECASTER STEWART

Issued at 1000 AM CDT Mon Sep 13 2021 000 WTNT34 KNHC 131435 TCPAT4 BULLETIN Tropical Storm Nicholas Advisory Number 6 NWS National Hurricane Center Miami FL AL142021 1000 AM CDT Mon Sep 13 2021 ...NICHOLAS MOVING ERRATICALLY NORTHWARD JUST OFFSHORE THE SOUTHERN COAST OF TEXAS... ...FLASH FLOODING, DANGEROUS STORM SURGE, AND GUSTY WINDS EXPECTED ALONG PORTIONS OF THE SOUTHERN AND MIDDLE TEXAS COASTS TODAY... SUMMARY OF 1000 AM CDT...1500 UTC...INFORMATION ----------------------------------------------- LOCATION...26.4N 96.8W ABOUT 45 MI...70 KM NE OF MOUTH OF THE RIO GRANDE ABOUT 140 MI...225 KM S OF PORT OCONNOR TEXAS MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H PRESENT MOVEMENT...N OR 5 DEGREES AT 12 MPH...19 KM/H MINIMUM CENTRAL PRESSURE...1002 MB...29.59 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: The Storm Surge Warning has been extended from San Luis Pass to Sabine Pass including Galveston Bay. The Hurricane Watch has been extended northeastward to San Luis Pass, Texas. The Tropical Storm Warning has been extended eastward to Sabine Pass. The Storm Surge Watch from the Mouth of the Rio Grande to Baffin Bay has been discontinued. The government of Mexico has discontinued the Tropical Storm Warning from Barra el Mezquital to the U.S./Mexico border. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Storm Surge Warning is in effect for... * Port Aransas Texas to Sabine Pass * Galveston Bay, Aransas Bay, San Antonio Bay, and Matagorda Bay A Hurricane Watch is in effect for... * Port Aransas to San Luis Pass Texas A Tropical Storm Warning is in effect for... * Mouth of the Rio Grande to Sabine Pass A Storm Surge Watch is in effect for... * Baffin Bay to Port Aransas Texas * Sabine Pass to Rutherford Beach Louisiana * Corpus Christi Bay A Storm Surge Warning means there is a danger of life-threatening inundation, from rising water moving inland from the coastline, during the next 36 hours in the indicated locations. For a depiction of areas at risk, please see the National Weather Service Storm Surge Watch/Warning Graphic, available at hurricanes.gov. This is a life-threatening situation. Persons located within these areas should take all necessary actions to protect life and property from rising water and the potential for other dangerous conditions. Promptly follow evacuation and other instructions from local officials. A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area. A Storm Surge Watch means there is a possibility of life-threatening inundation, from rising water moving inland from the coastline, in the indicated locations during the next 48 hours. For a depiction of areas at risk, please see the National Weather Service Storm Surge Watch/Warning Graphic, available at hurricanes.gov. A Hurricane Watch means that hurricane conditions are possible within the watch area. Interests elsewhere in southwestern Louisiana should monitor the progress of Nicholas. For storm information specific to your area in the United States, including possible inland watches and warnings, please monitor products issued by your local National Weather Service forecast office. For storm information specific to your area outside of the United States, please monitor products issued by your national meteorological service. DISCUSSION AND OUTLOOK ---------------------- At 1000 AM CDT (1500 UTC), the center of Tropical Storm Nicholas was located by NOAA Doppler weather radars and an Air Force Reserve reconnaissance aircraft near latitude 26.4 North, longitude 96.8 West. Nicholas is moving toward the north near 12 mph (19 km/h) and this general motion is expected to continue today, followed by a turn toward the north-northeast on Tuesday. On the forecast track, the center of Nicholas will pass near or just offshore of the coast of south Texas this morning and move onshore along the coast of south or central Texas late this afternoon or this evening. Data from the reconnaissance aircraft indicate that maximum sustained winds remain near 60 mph (95 km/h) with higher gusts. Strengthening is forecast today, and Nicholas could reach the northwest Gulf coast as a hurricane. Weakening is anticipated on Tuesday and Wednesday while Nicholas moves over land. Tropical-storm-force winds extend outward up to 115 miles (185 km) from the center. NOAA buoy 42020 located southeast of Corpus Christi, Texas, recently reported a sustained wind of 40 mph (65 km/h). The minimum central pressure recently measured by the aircraft is 1002 mb (29.59 inches). HAZARDS AFFECTING LAND ---------------------- Key messages for Nicholas can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDAT4, WMO header WTNT44 KNHC and on the web at hurricanes.gov/graphics_at4.shtml?key_messages RAINFALL: Nicholas is expected to produce storm total rainfall of 8 to 16 inches, with isolated maximum amounts of 20 inches, across portions of the middle and upper Texas coastal areas through the middle of the week. Life-threatening, flash and urban flooding impacts are possible, especially across portions of the upper Texas Gulf Coast near Lake Jackson and Freeport, TX Across the rest of southeast Texas into southwest Louisiana rainfall of 5 to 10 inches is expected. This rainfall may produce areas of considerable flash and urban flooding, especially in highly urbanized metropolitan areas. Additionally, there is the potential for isolated minor to moderate river flooding. STORM SURGE: The combination of a dangerous storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline. The water could reach the following heights above ground somewhere in the indicated areas if the peak surge occurs at the time of high tide... Port O'Connor to San Luis Pass TX including Matagorda Bay...3-5 ft San Luis Pass, TX to Rutherford Beach, LA including Galveston Bay...2-4 ft Baffin Bay to Port O'Connor, TX...2-4 ft Corpus Christi Bay, Aransas Bay and San Antonio Bay...2-4 ft Mouth of the Rio Grande to Baffin Bay...1-3 ft Rutherford Beach, LA to Intracoastal City, LA...1-3 ft Sabine Lake and Calcasieu Lake...1-3 ft The deepest water will occur along the immediate coast in areas of onshore winds, where the surge will be accompanied by large and dangerous waves. Surge-related flooding depends on the relative timing of the surge and the tidal cycle, and can vary greatly over short distances. For information specific to your area, please see products issued by your local National Weather Service forecast office. WIND: Tropical storm conditions are expected within the warning area in southern Texas through the next few hours. These conditions will spread northward within the warning area through tonight, making outside preparations difficult or dangerous. Hurricane conditions are possible in the Hurricane Watch area as early as this afternoon or this evening. TORNADOES: A couple of tornadoes are possible this afternoon and tonight across the middle and upper Texas coast. SURF: Swells generated by Nicholas will continue affecting portions of the northwest Gulf coast through Tuesday. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. NEXT ADVISORY ------------- Next intermediate advisory at 100 PM CDT. Next complete advisory at 400 PM CDT. $$ Forecaster Stewart

...NICHOLAS MOVING ERRATICALLY NORTHWARD JUST OFFSHORE THE SOUTHERN COAST OF TEXAS... ...FLASH FLOODING, DANGEROUS STORM SURGE, AND GUSTY WINDS EXPECTED ALONG PORTIONS OF THE SOUTHERN AND MIDDLE TEXAS COASTS TODAY... As of 10:00 AM CDT Mon Sep 13 the center of Nicholas was located near 26.4, -96.8 with movement N at 12 mph. The minimum central pressure was 1002 mb with maximum sustained winds of about 60 mph.

Issued at 1500 UTC MON SEP 13 2021 000 WTNT24 KNHC 131435 TCMAT4 TROPICAL STORM NICHOLAS FORECAST/ADVISORY NUMBER 6 NWS NATIONAL HURRICANE CENTER MIAMI FL AL142021 1500 UTC MON SEP 13 2021 CHANGES IN WATCHES AND WARNINGS WITH THIS ADVISORY... THE STORM SURGE WARNING HAS BEEN EXTENDED FROM SAN LUIS PASS TO SABINE PASS...INCLUDING GALVESTON BAY. THE HURRICANE WATCH HAS BEEN EXTENDED NORTHEASTWARD TO SAN LUIS PASS TEXAS. THE TROPICAL STORM WARNING HAS BEEN EXTENDED EASTWARD TO SABINE PASS. THE STORM SURGE WATCH FROM THE MOUTH OF THE RIO GRANDE TO BAFFIN BAY HAS BEEN DISCONTINUED. THE GOVERNMENT OF MEXICO HAS DISCONTINUED THE TROPICAL STORM WARNING FROM BARRA EL MEZQUITAL TO THE U.S./MEXICO BORDER. SUMMARY OF WATCHES AND WARNINGS IN EFFECT... A STORM SURGE WARNING IS IN EFFECT FOR... * PORT ARANSAS TEXAS TO SABINE PASS * GALVESTON BAY...ARANSAS BAY...SAN ANTONIO BAY...AND MATAGORDA BAY A HURRICANE WATCH IS IN EFFECT FOR... * PORT ARANSAS TO SAN LUIS PASS TEXAS A TROPICAL STORM WARNING IS IN EFFECT FOR... * MOUTH OF THE RIO GRANDE TO SABINE PASS A STORM SURGE WATCH IS IN EFFECT FOR... * BAFFIN BAY TO PORT ARANSAS TEXAS * SABINE PASS TO RUTHERFORD BEACH LOUISIANA * CORPUS CHRISTI BAY A STORM SURGE WARNING MEANS THERE IS A DANGER OF LIFE-THREATENING INUNDATION...FROM RISING WATER MOVING INLAND FROM THE COASTLINE...DURING THE NEXT 36 HOURS IN THE INDICATED LOCATIONS. FOR A DEPICTION OF AREAS AT RISK...PLEASE SEE THE NATIONAL WEATHER SERVICE STORM SURGE WATCH/WARNING GRAPHIC...AVAILABLE AT HURRICANES.GOV. THIS IS A LIFE-THREATENING SITUATION. PERSONS LOCATED WITHIN THESE AREAS SHOULD TAKE ALL NECESSARY ACTIONS TO PROTECT LIFE AND PROPERTY FROM RISING WATER AND THE POTENTIAL FOR OTHER DANGEROUS CONDITIONS. PROMPTLY FOLLOW EVACUATION AND OTHER INSTRUCTIONS FROM LOCAL OFFICIALS. A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE EXPECTED SOMEWHERE WITHIN THE WARNING AREA. A STORM SURGE WATCH MEANS THERE IS A POSSIBILITY OF LIFE-THREATENING INUNDATION...FROM RISING WATER MOVING INLAND FROM THE COASTLINE...IN THE INDICATED LOCATIONS DURING THE NEXT 48 HOURS. FOR A DEPICTION OF AREAS AT RISK...PLEASE SEE THE NATIONAL WEATHER SERVICE STORM SURGE WATCH/WARNING GRAPHIC...AVAILABLE AT HURRICANES.GOV. A HURRICANE WATCH MEANS THAT HURRICANE CONDITIONS ARE POSSIBLE WITHIN THE WATCH AREA. INTERESTS ELSEWHERE IN SOUTHWESTERN LOUISIANA SHOULD MONITOR THE PROGRESS OF NICHOLAS. TROPICAL STORM CENTER LOCATED NEAR 26.4N 96.8W AT 13/1500Z POSITION ACCURATE WITHIN 20 NM PRESENT MOVEMENT TOWARD THE NORTH OR 5 DEGREES AT 10 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1002 MB MAX SUSTAINED WINDS 50 KT WITH GUSTS TO 60 KT. 50 KT....... 30NE 0SE 0SW 0NW. 34 KT.......100NE 80SE 0SW 0NW. 12 FT SEAS.. 60NE 30SE 0SW 0NW. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT. REPEAT...CENTER LOCATED NEAR 26.4N 96.8W AT 13/1500Z AT 13/1200Z CENTER WAS LOCATED NEAR 25.4N 96.9W FORECAST VALID 14/0000Z 27.5N 96.7W MAX WIND 60 KT...GUSTS 75 KT. 50 KT... 50NE 20SE 0SW 0NW. 34 KT...120NE 100SE 30SW 30NW. FORECAST VALID 14/1200Z 29.1N 96.3W...INLAND MAX WIND 45 KT...GUSTS 55 KT. 34 KT...100NE 100SE 20SW 20NW. FORECAST VALID 15/0000Z 30.2N 95.4W...INLAND MAX WIND 30 KT...GUSTS 40 KT. FORECAST VALID 15/1200Z 31.0N 94.0W...INLAND MAX WIND 25 KT...GUSTS 35 KT. FORECAST VALID 16/0000Z 31.5N 92.5W...INLAND MAX WIND 20 KT...GUSTS 30 KT. FORECAST VALID 16/1200Z 32.0N 91.1W...POST-TROP/REMNT LOW MAX WIND 20 KT...GUSTS 30 KT. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 150 NM ON DAY 4 AND 175 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY OUTLOOK VALID 17/1200Z...DISSIPATED REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 26.4N 96.8W INTERMEDIATE PUBLIC ADVISORY...WTNT34 KNHC/MIATCPAT4...AT 13/1800Z NEXT ADVISORY AT 13/2100Z $$ FORECASTER STEWART

000
ABNT20 KNHC 131119
TWOAT

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Mon Sep 13 2021

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

The National Hurricane Center is issuing advisories on Tropical
Storm Nicholas, located over the western Gulf of Mexico.

A tropical wave has emerged off the west coast of Africa near
the coasts of Guinea and Sierra Leone. Environmental conditions
are forecast to be conducive for gradual development of this
disturbance, and a tropical depression is likely to form by late
this week while the system moves westward at 10 to 15 mph across
the eastern tropical Atlantic Ocean.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 5 days...high...80 percent.

An area of low pressure is forecast to form by midweek a couple of
hundred miles north of the southeastern or central Bahamas as a
tropical wave interacts with an upper-level trough. Some gradual
development of this system is possible thereafter, and a tropical
depression could form later this week while the system moves
north-northwestward or northward across the western Atlantic.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...medium...50 percent.

&&
Public Advisories on Tropical Storm Nicholas are issued under
WMO header WTNT34 KNHC and under AWIPS header MIATCPAT4.
Forecast/Advisories on Tropical Storm Nicholas are issued under
WMO header WTNT24 KNHC and under AWIPS header MIATCMAT4.

$$
Forecaster Stewart

Potential Storm Surge Flooding Map last updated Mon, 13 Sep 2021 09:56:45 GMT

5-Day Uncertainty Track last updated Fri, 10 Sep 2021 14:50:03 GMT


Wind Speed Probabilities last updated Fri, 10 Sep 2021 15:22:52 GMT