It is hard to believe that the Atlantic is at the Greek letters. The last time that happened was in 2005. The Greek letters did come into use until October 2005. So many storms have formed in September 2020. Now, there is Beta off the coast of Texas. It is currently a tropical storm with 60 mph winds and is stationary per National Hurricane Center (NHC).
000
WTNT32 KNHC 192100
TCPAT2BULLETIN
Tropical Storm Beta Advisory Number 9
NWS National Hurricane Center Miami FL AL222020
400 PM CDT Sat Sep 19 2020…BETA NOW STATIONARY OVER THE NORTHWESTERN GULF OF MEXICO…
…STORM SURGE WARNING ISSUED FOR PORTIONS OF THE TEXAS COAST…SUMMARY OF 400 PM CDT…2100 UTC…INFORMATION
———————————————-
LOCATION…26.6N 92.4W
ABOUT 320 MI…510 KM ESE OF CORPUS CHRISTI TEXAS
ABOUT 245 MI…395 KM SSE OF LAKE CHARLES LOUISIANA
MAXIMUM SUSTAINED WINDS…60 MPH…95 KM/H
PRESENT MOVEMENT…STATIONARY
MINIMUM CENTRAL PRESSURE…994 MB…29.36 INCHESWATCHES AND WARNINGS
——————–
CHANGES WITH THIS ADVISORY:A Storm Surge Warning is now in effect for Port Aransas, Texas to
High Island, Texas including Copano Bay, Aransas Bay, San Antonio
Bay, Matagorda Bay, and Galveston Bay.A Storm Surge Watch has been discontinued for Port Mansfield, Texas
to Baffin Bay, Texas.SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
A Storm Surge Warning is in effect for
* Port Aransas, Texas to High Island, Texas including Copano Bay,
Aransas Bay, San Antonio Bay, Matagorda Bay, and Galveston BayA Storm Surge Watch is in effect for…
* Baffin Bay, Texas to Port Aransas, Texas including Baffin Bay and
Corpus Christi Bay
* High Island, Texas to Cameron, Louisiana including Sabine Lake
and Lake CalcasieuA Hurricane Watch is in effect for…
* Port Aransas Texas to High Island TexasA Tropical Storm Warning is in effect for…
* Port Aransas Texas to Intracoastal City LouisianaA Tropical Storm Watch is in effect for…
* South of Port Aransas Texas to the Mouth of the Rio Grande
* East of Intracoastal City Louisiana to Morgan City LouisianaA 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 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. A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.A Hurricane Warning may be required for portions of the Texas coast
tonight.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 400 PM CDT (2100 UTC), the center of Tropical Storm Beta was
located near latitude 26.6 North, longitude 92.4 West. Beta has
been nearly stationary for the past several hours. A westward
drift is expected tonight, followed by a slow motion toward the
west-northwest that should continue through late Monday. On the
forecast track, the center of Beta will slowly approach the Texas
coast Sunday and Monday.Maximum sustained winds are near 60 mph (95 km/h) with higher gusts.
Slow strengthening is expected during the next couple of days,
and Beta could be near hurricane strength as it approaches the
Texas coast.Tropical-storm-force winds extend outward up to 175 miles (280 km)
from the center, mainly in the northern semicircle. A ship near
the center of Beta recently reported winds of 54 mph (87 km/h).The estimated minimum central pressure is 994 mb (29.36 inches).
HAZARDS AFFECTING LAND
———————-
Key messages for Beta can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT2 and WMO header WTNT42 KNHC.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…Baffin Bay, TX to Cameron, LA including Baffin Bay, Corpus Christi
Bay, Copano Bay, Aransas Bay, Matagorda Bay, Galveston Bay, Sabine
Lake, Calcasieu Lake, San Antonio Bay…2-4 ft
Cameron, LA to Ocean Springs, MS including Vermilion Bay…1-3 ft
Lake Borgne, Lake Pontchartrain, and Lake Maurepas…1-3 ft
Mouth of the Rio Grande to Baffin Bay, TX…1-2 ftThe 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 in the tropical storm
warning area by Sunday night. Hurricane conditions are possible
within the hurricane watch area by late Monday or Monday night.
Tropical storm conditions are possible within the tropical storm
watch area along the southwestern Louisiana coast as early as
tonight, and are possible within the tropical storm watch area
along the south Texas coast Sunday night or Monday.RAINFALL: Beta has the potential to produce a long duration
rainfall event along the western Gulf Coast. Today through Tuesday,
Beta is expected to produce rainfall accumulations of 8 to 12
inches with isolated totals of 20 inches beginning Saturday across
southern Louisiana and spreading into coastal Texas on Sunday. Flash
and urban flooding is likely as well as minor river flooding.
Additional heavy rainfall amounts across the western Gulf Coast are
possible through late week as Beta is expected to move slowly near
the Texas coast.SURF: Swells are increasing and reaching the coast of Texas and
the Gulf Coast of Mexico, generated by a combination of Beta and a
cold front entering the northern Gulf of Mexico. 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 700 PM CDT.
Next complete advisory at 1000 PM CDT.$$
Forecaster Beven
Here is the forecast model for Beta. It is a heat map using points within 300 mile/480 kilometers radius. I used the latest forecast, which is 1800Z. All GIS maps are created from QGIS. The data and intensity forecast are from NCAR-Tropical Cyclone Guidance.
The circular shape of the the heat map tells me this is a low confidence forecast. It is all over the place of where Beta will go in the next few days. The forecast adds a lot of uncertainty on top uncertain times due to COVID-19 pandemic. The only consensus is Texas will be impacted by Beta. The forecast model reminds me of Harvey back in 2017. It lingered over Texas for a few days dumping heavy rain over a large area leading to massive flooding. It is going to be hard to say where Beta will go as the forecast model keep changing. Here is the intensity forecast for Beta.
Most of the intensity forecast models keep Beta as a tropical storm. Intensity forecast model is even less reliable than where it will go. There is a lot of lightning in the main central dense overcast (CDO) and outer rainbands. Here is a lightning flash map from GOES-East CONUS – Geostationary Lightning Mapper.
There is a lot of lightning. Lightning on the outer band can be a sign the storm is intensifying. Here is a study that shows that lightning in the outer bands is a sign of intensification titled Tropical Cyclone Lightning and Rapid Intensity Change.
Abstract
A large sample of Atlantic and eastern North Pacific tropical cyclone cases (2005–10) is used to investigate the relationships between lightning activity and intensity changes for storms over water. The lightning data are obtained from the ground-based World Wide Lightning Location Network (WWLLN). The results generally confirm those from previous studies: the average lightning density (strikes per unit area and time) decreases with radius from the storm center; tropical storms tend to have more lightning than hurricanes; intensifying storms tend to have greater lightning density than weakening cyclones; and the lightning density for individual cyclones is very episodic. Results also show that Atlantic tropical cyclones tend to have greater lightning density than east Pacific storms. The largest lightning density values are associated with sheared cyclones that do not intensify very much. The results also show that when the lightning density is compared with intensity change in the subsequent 24 h, Atlantic cyclones that rapidly weaken have a larger inner-core (0–100 km) lightning density than those that rapidly intensify. Thus, large inner-core lightning outbreaks are sometimes a signal that an intensification period is coming to an end. Conversely, the lightning density in the rainband regions (200–300 km) is higher for those cyclones that rapidly intensified in the following 24 h in both the Atlantic and east Pacific. When lightning density parameters are used as input to a discriminant analysis technique, results show that lightning information has the potential to improve the short-term prediction of tropical cyclone rapid intensity changes.
The large number of lightning in CDO may suggest that slowing intensification. However, the number of lightning on the outer rainbands indicates that Beta could be intensifying. To make things more complicated, there is is a lot of dry air that Beta has to contend with. Dry air tends to inhibit intensification of tropical cyclones. Here is the most recent water vapor imagery at mid-level. It is from GOES-East.
NOAA/NESDIS/STAR GOES ABI BAND 09 OR_ABI-L1b-RadC-M6C09_G16_s20202632046161_e20202632048539_c20202632049048.nc
Depending how much dry air is, Beta may not intensify past tropical storm. So much variables come to play. The intensity forecast is even more uncertain than where it goes. I think Beta will be a strong tropical storm to Category 1 hurricane. I would not rule out Category 2 hurricane, but that is unlikely.
Beta is going to a hard storm to forecast for the next few days. Beta adds a lot of uncertainty on top uncertainty with the COVID-19 pandemic.
Texas Hurricane 