Nate Is Edging Closer To The Gulf Coast

Nate is now a Category 1 hurricane with 90 mph 144 km/h 78 knots wind. Further strengthening is possible with Nate. The question is how strong will Nate be by landfall.

Most forecast models have Nate intensifying into Category 2 with one intensifying into Category 3 hurricane. I would not be surprised if Nate becomes a Category 3 hurricane upon landfall. Category 4 or 5 is highly unlikely as it is moving quickly at 26 mph 42 km/h 22.6 knots. Here is a forecast model of where Nate will possibly make landfall. The heat map is from within 300 miles (480 kilometers) of a point.

There is a consensus that Nate could make landfall southwest of New Orleans to Pensacola area. It is unlikely Nate could deviate and hit Harvey ravaged Texas Coast. At this rate, Nate could make landfall later tonight or early tomorrow morning. Tropical storm force winds could start later this afternoon to evening.

Nate is not a large hurricane. Here is a wind radii map of Nate.

Hurricane force winds are only on the east side of Nate. Hurricane force winds are up to 69 miles 110.4 km 60 nautical miles across from northeast to southeast quadrant. Tropical storm force winds are are up to 230 miles 368 km 200 nautical miles across from northeast to southeast quadrant. However, since Nate is moving quickly, hurricane force winds maybe felt up to nearly three hours on the eastern side of Nate. Tropical storm force winds maybe felt up to nine hours.

The motion Nate is moving at, many areas could see 4 to 8 inches/10.2 to 20.3 centimeters of rain with isolated totals as high as 12 inches/30.5 centimeters. The forward motion should keep inland flooding risk low at this time.

Here is what I think will happen.
-Nate will make landfall somewhere along the Gulf Coast.
-Coastal flooding will be the main problem.

The forecast models came from NCAR-Tropical Cyclone Guidance and National Hurricane Center. Special thanks to all of them.

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Tropical Depression 16 (Future Nate)

Tropical Depression 16 just formed. It could be Nate soon. It is October and it can be active. October has produce some very intense hurricanes like Great Hurricane Of 1780, 1924 Cuba Hurricane, Hattie, Opal, Mitch, Wilma, and Matthew. In fact some of the most intense tropical cyclones known have occurred in October like Tip, Patricia, Wilma, and 1999 Odisha Cyclone. They are the most intense tropical cyclones in their basin in the Northern Hemisphere! Here is the heat map forecast from various forecast models and GFS ensemble track guidance for Tropical Depression 16. The heat map is from within 300 miles (480 kilometers) of a point.

Most of the forecast models suggest that Tropical Depression 16 may go over Central America and then go over the Caribbean. From there, it enters the Gulf of Mexico. This is what concerns me.

The Northwest Caribbean off the coast of Belize and Yucatan Peninsula is very warm. If conditions are right in the atmosphere, Tropical Depression 16 or future Nate could undergo rapid intensification. Warm water is not the only factor that allows hurricanes to rapidly intensify. If the upper air is favorable like more humidity and less wind shear combined with warm water, it could allow rapid intensification. This is the same area where Wilma became the most intense hurricane in the Atlantic. Here is the intensity forecast.

Only one forecast model has future Nate as a major hurricane. Forecasting strength and intensity is notoriously difficult. I would not be surprised if Tropical Depression 16 or future Nate becomes a major hurricane.

Here is what I think will happen.
-Nate will form as early as Thursday.
-Caribbean and Gulf of Mexico needs to watch.

The forecast models came from NCAR-Tropical Cyclone Guidance and Tropical Cyclone Heat Potential. Special thanks to all of them.

Tropical Storm Franklin For 8/9/2017 1900 CDT

The first hurricane of the season, Franklin, is getting ever closer to Mexico. It looks to be that way.

Franklin is a Category 1 hurricane with 75 mph 120 km/h 65 knots wind. It has gusts of 94 mph 150.4 km/h 82 knots. Further intensification is possible as shown in the forecast model. Two models keep Franklin as a hurricane despite being over the mountains of Mexico. I am not convinced that will happen as the mountains tend to weaken hurricanes.

I would not be surprised if Franklin becomes a Category 2 hurricane with 105 mph 168 km/h 90 knots wind right before landfall as looks to be intensifying further. Franklin is an average sized hurricane. Tropical storm force winds extend up to 140 miles 224 km/h 122 nautical miles. Hurricane force winds extend up to 35 miles 56 km/h 30 nautical miles. from the eye.

Most areas in Mexico will see at most tropical storm force winds with hurricane force winds. Hurricane force winds should be most likely confined to the coast. Here is a probability map of hurricane force winds.

If Franklin makes landfall as a 85 mph 136 km/h 74 knots hurricane, the strongest wind possible is 72 mph 115 km/h 63 knots with gusts as high as 108 mph 173 km/h 94 knots. I determine this by multiplying the strongest winds by 0.85. Land reduces wind by 15 percent. However, due to friction, gusts are higher as I multiply sustained winds by 1.5.

My main concern is heavy rain from Franklin. Franklin is moving as 12 mph, which means it can dump about 8 inches (20.32 centimeters) of rain. Many areas are likely to see 4 to 10 inches (10.16 to 25.4 centimeters) of rain. Mountains areas could see as much as 20 inches (50.8 centimeters) of rain. This amount is certainly going to lead to flooding that can be deadly.

Tropical Storm Franklin For 8/8/2017 2200 CDT

Tropical Storm Franklin has exited the Yucatan Peninsula as a tropical storm. It is over the Gulf of Mexico as I type. It looks to be intensifying. The intensity and where it goes forecast models are always interesting and challenging. There are different outputs from different forecast models.

Most keep Franklin as a tropical storm. Three of them have Franklin becoming a Category 1 hurricane. The National Hurricane Center has Franklin as a hurricane in 24 hours. It would be the first hurricane of the season. I think Franklin will be a hurricane as it is over the Gulf of Mexico. I do not think Franklin will be a major hurricane. At most a strong Category 1 hurricane. The next question is where Franklin will make its next landfall.

Most of the forecast models have Franklin going into Mexico by tomorrow afternoon. One model has it going northwest towards Texas. That looks very unlikely at this point. The general consensus is Franklin is going to make landfall somewhere on Mexico’s Gulf Coast. Franklin is likely to make landfall somewhere on Mexico as a Category 1 hurricane. By tomorrow night, Franklin will be over the mountains of Mexico. Heavy rain will be the main problem as mountainous areas tend to draw more moisture from clouds.

Many areas could see 4 to 8 inches (10.16 to 20.32 centimeters) of rain. Some areas could see as much as 20 inches (50.8 centimeters) of rain, especially in mountainous areas. Looking at Franklin, I think it will be more of a rain and flood event.

Tropical Storm Franklin For 8/7/2017 2200 CDT

Tropical Storm Franklin is about to make landfall on Yucatan Peninsula as I type. Franklin has 60 mph 96 km/h 52 knot winds. Gusts are high as 75 mph 120 km/h 64 knots. The highest wind at landfall should be 51 mph 81.6 km/h 44 knots with gusts as high as 77 mph 123 km/h 67 knots. Many areas will likely see tropical storm force winds and heavy rain. Many areas will see 4 to 7 inches (10.16 to 17.78 centimeters) of rain with isolated totals of 12 inches (30.48 centimeters). Tropical storm force winds extend up to 140 miles 224 km 122 nautical miles.

Where doe Franklin go after it passes Yucatan Peninsula and how strong will it be? Most of the forecast model has Franklin going over Bay of Campeche and into Mexico again. One forecast model has it heading towards the Central Texas Coast. However, I do not think Franklin will have much of an impact on Texas as it is likely to move westward. The heat map is generated from ATCF data file. The cone is from National Hurricane Center.

Looking at the heat map, there is a general consensus that Franklin is likely going to make landfall on Mexico again. Intensity is of most concern. Here is an intensity forecast from National Center for Atmospheric Research.

Most forecast models have Franklin as a tropical storm as it goes over Yucatan Peninsula. Once it enters the Gulf of Mexico, some forecast models have Franklin becoming our first hurricane of the season with 75 mph 120 km/h 65 knots winds. I think Franklin will be our first hurricane of the season. I would not be surprised if Franklin intensified into a Category 2 hurricane.

Atlantic Hurricane Season In August

It is now August and the season is heating up. Where do most August tropical storms and hurricanes form and end up going?

Here is a GIS heat map I created. This is all August tropical storms and hurricanes from 1870 to 2015. The heat map is from within 300 miles (480 kilometers) of a point.

The Main Development Region (MDR) heats up. The Windward Islands see more tropical cyclones making landfall. Interestingly, there is a dead area around Central Caribbean and Cuba. The Gulf of Mexico and Southeast is very active. Many tropical cyclones form near land in August and make landfall. Some of the of most devastating tropical storms and hurricanes made landfall in August:
Sea Islands (1893)
San Ciriaco (1899)
Monterrey (1909)
1945 Texas Hurricane (1945)
Camille (1969)
Amelia (1978)
David (1979)
Alicia (1983)
Bob (1991)
Andrew (1992)
Charley (1998)
Charley (2004)
Katrina (2005)
Dean (2007)
Irene (2011)

Despite Amelia making landfall on July 31, 1978, the worst aspect was heavy rain from August 1-4, 1978 in Central and West Texas, where up to 46 inches (116.84 centimeters) of rain fell. The costliest hurricane occurred in August, Katrina. The previous prior to Katrina was Andrew. August has produced some of the most devastating tropical storms and hurricanes.

Texas does get hurricane landfalls in August, including major hurricanes like Allen and Alicia. Allen was a Category 5 monster and almost made landfall on Port Mansfield as a Category 5 with 180 mph winds. Had that happened, that would of been really devastating. Allen made landfall as a Category 3 hurricane with 115 mph winds. Allen was a very large hurricane upon landfall. Alicia made landfall on Galveston as a Category 3 hurricane with 115 mph winds. It was Texas’s first billion dollar disaster. Alicia was a medium size hurricane, unlike Allen. Had Alicia been Allen, Carla, or Ike size, it would been much worse.

Atlantic Hurricane Season In July

It is now July and it is the halfway mark of the year. Where do most July tropical storms and hurricanes form and end up going?

Here is a GIS heat map I created. This is all July tropical storms and hurricanes from 1870 to 2015. The heat map is from within 300 miles (480 kilometers) of a point.

Most July tropical cyclones form in the Gulf of Mexico and off the Carolinas, Georgia, and Florida. Texas, Louisiana, Mississippi, and Alabama are at most risk to see a tropical cyclone making landfall in July. America’s 24 hour rainfall record is from a July tropical cyclone, Tropical Storm Claudette in 1979. Some of the biggest flood events from tropical storms have occurred in July like Alberto in 1994 and Danny in 1997. Alberto did form in late June, but most of its life was in July, so Alberto can be considered a July tropical cyclone.