Tropical Storm Nicholas Advisory Number 6
NWS National Hurricane Center Miami FL AL142021
1000 AM CDT Mon Sep 13 2021
...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
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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
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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. 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.
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
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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
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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.
Forecaster Stewart
