More Rain Tonight?

The tropical wave is now over Texas. It is a disorganized system, so it is hard to predict where the rain will be tonight. Let’s look at High-Resolution Rapid Refresh (HRRR), North American Mesoscale Forecast System (NAM), Regional Model (RGEM), and Weather Research and Forecast (WRF-ARW, and WRF-NMM). They are at 0900Z or 4:00 AM CDT.

The HRRR has heavy rain mostly west and southwest of Houston. The NAM has heavy rain over Matagorda Bay and east of Houston. The RGEM has an axis of heavy rain from Corpus Christi area to East Texas. The WRF-ARW has the heavy rain over Matagorda Bay. The WRF-NMM has heavy rain south of San Antonio. This shows that forecasting where heavy rain will fall tonight is all over the place with this tropical wave.

Looking at the most recent Doppler radar mosaic, there is heavy rain over East Texas and Southwest Louisiana. It is not really active right now.

However, with tropical moisture, thunderstorms tend to form at night, especially near the center of the low pressure system. They are called core rains and they can dump heavy rain in a short time. Harvey, Allison, Claudette, and Thrall 1921 Flood were core rain events as flooding rain fell at night. This system is disorganized, so it will be hard to tell where it will exactly form. Some forecast models want the heavy rain over Matagorda Bay, while some have it over Southeast Texas.

Many are wondering what is the forecasted rain amount. The rainfall forecast models are from GFS, Canadian, EURO, ICON, and Weather Prediction Center (WPC). They are all 7 day rainfall total forecast.

The GFS has 4 inches of rain over Galveston Bay. The area of heaviest rain is east of Houston.

The Canadian has nearly 11 inches of rain just north of Houston. The largest area of heavy rain is north of Houston.

The EURO has backed down on nearly 30 inches of rain. It has nearly 15 inches of rain south of San Antonio. There is a large area of heavy rain southwest of Houston.

The ICON has over 13 inches of rain near Aransas Pass. There is an area of 8 inches of rain west of Houston. Most of the heavy rain is over the Gulf Of Mexico.

The WPC has 10 inches of rain over an Matagorda Bay and Victoria. Houston area has 5 to 7 inches of rain.

The rainfall forecast is all over the place on where it will fall and even the amount. This is a very frustrating forecast. Regardless of forecast models, all forecast heavy rain will fall somewhere.

Here is what I think will happen.
-Someone will see heavy rain tonight.
-Not ruling out Houston area getting heavy rain tonight.
-Rainfall amounts could range from 5 to 10 inches of rain with isolated totals approaching and exceeding 15 inches.

The forecast models came from Weather.US, Tropical Tidbits, National Hurricane Center, and National Weather Service. Special thanks to all of them.

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Invest 91L As This Weekend’s Rainmaker?

Invest 91L is over the Gulf of Mexico. Currently on satellite from CIMSS-Tropical Cyclones, it does not look too impressive.

Of course with tropical lows, they tend to fire up at night as they are warmer than the surrounding area. I would not be surprised to see a lot of thunderstorms come morning. As the time passes, where does Invest 91L go?

Most forecast models have it going towards South Texas or Mexico. There is a chance that it could go over Southeast Texas. If it goes into Mexico or South Texas, there is better chance for rain since the northeast side is the wettest as it is the “dirty” side of the tropical low. The intensity forecast models are split.

Some have Invest 91L as a tropical wave. Some have it intensifying into a tropical depression. Some have it becoming a tropical storm. If it becomes a tropical storm, it would be Beryl. Like I say, intensity forecast is not really reliable. At this point, I would be more concerned with the rain than some tropical storm developing.

Various forecast models have different rain amounts, which are from GFS, Canadian, EURO, and Weather Prediction Center (WPC). They are from Weather.US and Weather Prediction Center (WPC)-Quantitative Precipitation Forecasts (QPF). These are 7 day rainfall totals.

The GFS has the heaviest rain over Houston area. It forecasts up to 8 inches of rain. A large area of Southeast Texas has 3 to 6 inches of rain.

The Canadian forecasts rain amounts of up to 6 inches over Austin area and around Halletsville.

The EURO forcasts up to 20 inches of rain southeast of San Antonio. There is 10 inches south of Houston. The EURO is the wettest of the forecast models.

The WPC has up to 5 inches of rain over Southeast Texas. It is the driest of the forecast models.

All the forecast models have rain for Texas. The only difference is the amount. Some are very bullish, while others are not. The plus side is that it will put a dent on the drought in Texas.

Most areas in Texas are in a drought. The rains can alleviate the drought, which is a good thing. This also increases the risk for flooding, which is not good almost a year after Harvey ravaged Texas with epic rainfall.

I think Invest 91L will be more of a rain event this weekend. Tropical development is not likely, but cannot be ruled out. Regardless, Invest 91L needs to be watched as it could be more of a rain event that may cause flooding in some areas.

The forecast models came from NCAR-Tropical Cyclone Guidance. The GIS drought map is from United States Drought Monitor.

A Weakening Bud And Invest 91L

Oh how the mighty have fallen! Yesterday, Bud was a hurricane. Today it is a tropical storm with 50 mph 44 knots 80 km/h winds. It was once a formidable Category 3 hurricane. All the forecast models have Bud weakening.

With Bud running into cooler water and closer to land, it is most likely to weaken. The next important question is where Bud goes.

The forecast models are having Bud moving towards Baja California and the Southwestern US as a low pressure system. The moisture from Bud is certainly welcomed in the Southwest as they are very dry.

Almost the entire Four Corners is engulfed in a severe drought. It centers around where the Four Corners meet. There is also a severe drought in the Texas Panhandle region. Any rain is welcomed regardless. This leads to Invest 91L in the Caribbean. Many are asking where 91L will go.

Most of the forecast models have Invest 91L heading towards either Mexico or Deep South Texas. Some have it heading towards Southeast Texas. Regardless of where 91L goes, rain will be the main issue. Since Invest 91L is over an area of warm water, does it have a chance of developing?

Most forecast models have 91L at tropical wave or tropical depression. One has it as a tropical storm. Again, it is too early to tell if it will develop. Tropical waves or low pressure areas in the Caribbean and Gulf of Mexico can form suddenly into a tropical storm or even hurricane. It has happened many times in the past. I am not suggesting it will happen with 91L. It is something to consider.

The Tropical Cyclone Formation Probability Guidance Product does give Invest 91L a chance of developing into a tropical cyclone in the next 48 hours. Again, that is only a small chance of developing.

Since, we are on the topic of tropical weather trouble, it brings rain. Various forecast models have different rain amounts, which are from GFS, Canadian, EURO, and Weather Prediction Center (WPC). They are from Weather.US and Weather Prediction Center (WPC)-Quantitative Precipitation Forecasts (QPF). These are 7 day rainfall totals.

The GFS has less rain for Texas and the Southwest. Southeast Texas has 2 to 4 inches of rain. The Southwest sees 0.50 to 2 inches of rain with 6 inches in the mountains.

The Canadian is not particularly generous for the Southwest. However for Southeast, Texas it has up to 8 inches of rain.

The EURO is generous for Southwest and Texas. The mountains of Arizona, New Mexico, and Colorado have up 8 inches of rain. Most of Arizona is wet as well compared to GFS and Canadian.

The WPC has 2 to 4 inches of rain over Southeast Texas. The Southwest has 0.50 to 1 inches of rain with isolated areas seeing 2 inches of rain.

The forecast models are unanimous on that rain will fall in Texas and the Southwest. They diverge on rain amount. Some forecast lesser amounts, while others forecast higher amounts. We should have a better idea of rain amounts later on.

My take on this. Invest 91L is more likely going to be a rain event. I do not expect 91L will develop at this point, but of course anything can happen. I do not think we will see another Harvey event from 91L. It is not forecasted to linger over Texas, like what Harvey or Allison did. As for Bud, the Southwestern US should welcome the rain with open arms. They will need it for sure.

The forecast models came from NCAR-Tropical Cyclone Guidance. The GIS drought map is from United States Drought Monitor.

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.

Puerto Rico In Trouble

Hurricane Maria is a very dangerous Category 5 hurricane with 175 mph 280 km/h 152 knots. It has a central pressure of 909 millibars (mb). This is more intense than Hurricane Irma in terms of central pressure. Maria is now the top 10 most intense Atlantic hurricane known. I mean known as records go back to 1851.

Top 10 Most Intense Hurricane By Central Pressure
1.) Wilma 2005 882 mb
2.) Gilbert 1988 888mb
3.) Labor Day 1935 892 mb
4.) Rita 2005 895 mb
5.) Allen 1980 899 mb
6.) Camille 1969 900 mb
7.) Katrina 2005 902 mb
8.) Mitch 1998/Dean 2007 905 mb
9.) Maria 2017 909 mb
10.) Cuba 1932/Ivan 2004 910 mb

Wilma is the most intense hurricane to date. It ravaged Yucatan Peninsula and Florida. Gilbert and Rita caused a huge scare for Texas. Gilbert hit Jamaica, Yucatan Peninsula, and Mexico’s Gulf Coast. Rita hit east of Houston area in East Texas and Southwest Louisiana. Labor Day 1935 Hurricane likely had low central pressure. Allen made landfall on South Texas. Camille and Katrina ravaged the Gulf Coast in the same area. Katrina was larger as it produced higher storm surge in Mississippi and flooded out New Orleans. Mitch killed 22,000 from heavy rain and massive flooding in Central America. Mitch is the deadliest hurricane after the Great Hurricane of 1780, which claimed 30,000 lives. Dean hit Yucatan Peninsula and Mexico. Cuba 1932 is Cuba’s deadliest hurricane to this day. Ivan ravaged the the Caribbean before making landfall on Alabama and Florida. Ivan came back again and made landfall as a tropical storm on Texas/Louisiana border. That being said, Maria is getting ever so closer to St. Croix and Puerto Rico.

Doppler radar image out of Puerto Rico shows a formidable Hurricane Maria. Not often we see a Category 5 hurricane on ground based Doppler radar. It has a near prefect circular eye. The infrared satellite image of Hurricane Maria is very impressive and scary. It is going to be a rough night for St. Croix.

St. Croix is experiencing tropical storm force winds. Hurricane force winds should be later tonight for St.Croix. Puerto Rico should feel tropical storm force winds later tonight. Hurricane force wind comes early tomorrow morning. Hurricane force winds are up to 104 miles 166 km 90 nautical miles across from northwest to northeast quadrant. Tropical storm force winds are are up to 276 miles 442 km 240 nautical miles across from northwest to northeast quadrant. It has gotten larger from yesterday. The speed Maria is moving at, 10 mph 16 km/h 8.7 knots, tropical storm force winds could last up to nearly 28 hours, while hurricane force winds could last up to 10 hours. This prolonged wind could do a lot of damage for Puerto Rico and St. Croix.

Here is the heat map forecast from various forecast models and GFS ensemble track guidance for Maria up close with Puerto Rico.

It does not look good for Puerto Rico. Most of the forecast models have Maria making landfall and going over Puerto Rico. The intensity as it is is very concerning. I would not be surprised if Maria intensifies further right before it gets close to Puerto Rico later tonight. This is a very bad for Puerto Rico. If Hurricane Maria makes landfall as a Category 5 on Puerto Rico, it will be the first since 1928, the Okeechobee Hurricane. On September 13, 1928, the Okeechobee Hurricane made landfall on Puerto Rico as a Category 5 hurricane with 160 mph 256 km/h 139 knots. The gusts are as high as 240 mph 384 km/h 209 knots. It had a central pressure of 929 millibars. It was very likely the central pressure was lower and stronger. The hurricane was large as it ravaged Puerto Rico. The hurricane claimed 312 lives in Puerto Rico, while 1,200 lives were lost at Guadeloupe. The Okeechobee Hurricane made landfall near West Palm Beach as a Category 4 hurricane with 145 mph 232 km/h 126 knots on September 17, 1928. The highest wind on land would be around 123 mph 200 km/h 107 knots with gusts as high as 185 mph 296 km/h 161 knots. The hurricane stayed over Florida and claimed at least 2,500 lives and likely more. The Okeechobee Hurricane claimed more than 4,000 lives. The death toll is likely much higher. It is America’s deadliest hurricane since 1900 Galveston Hurricane that claimed 12,000 lives. In fact, Okeechobee Hurricane is the deadliest American disaster prior to 9/11 and Hurricane Katrina.

Once Maria passes Puerto Rico, where does it go?. This is the latest heat map from various forecast models and GFS ensemble track guidance for Maria. The GFS goes up to 10 days.

The forecast models have a westward trend from 24 hours ago. Dominican Republic and Bahamas could feel the impact of Maria. There is also a possibility that Maria could affect North Carolina and the Eastern Seaboard. That would be too early to tell at this time. This is on top of how strong Maria will be.

Most of the forecast models have Maria weakening after it passes Puerto Rico. One model has Maria intensifying back to a Category 5 hurricane in three days. Intensity forecast are notoriously difficult to forecast. All the forecast models are subject to change.

Here is what I think will happen.
-Maria could pose a major threat to Puerto Rico.
-Maria will likely impact Dominican Republic.

This is going to be very bad for Puerto Rico and St. Croix. I fear the damage will be epic and the death toll could be high. This comes at a bad time as Puerto Rico is mired in a serious financial crisis. This could make recovery difficult for Puerto Rico. I cannot imagine what it will be like during Hurricane Maria.

The forecast models came from NCAR-Tropical Cyclone Guidance, NOAA Tropical Cyclone Imagery – Storm Floaters, National Hurricane Center, and National Weather Service. Special thanks to all of them.

Double Trouble!

The Natonal Hurricane Center (NHC) has confirmed that Hurricane Maria made landfall as a formidable Category 5 hurricane with 160 mph 256 km/h 139 knots wind. Gusts can go as high as 240 mph 384 km/h 209 knots! It has a central pressure 924 millibars. Maria is the second Category 5 hurricane of 2017 for the Atlantic. The last time there were more than one Category 5 hurricane was in 2007 with Dean and Felix. 2005 had four Category 5 hurricanes; Emily, Katrina, Rita, and Wilma. This is going to be a very long night for the people of Dominica. I cannot imagine what it is like to be under a Category 5 monster. Strong and howling winds and buildings getting destroyed.

The hurricane force winds is going to engulf most if not all of Dominica.

Hurricane force winds are up to 58 miles 93 km 50 nautical miles across from northwest to northeast quadrant. It is moving at 9 mph 14 km/h 7.8 knots, which means they will have to endure hurricane force winds for about 6 hours! That is a very prolonged, which increases chance for great carnage in Dominica. At that speed, Hurricane Maria will dump between 8 to 12 inches/20.3 to 30.5 centimeters of rain. Some areas could see as much as 20 inches/50.8 centimeters of rain.

The big question is where the Maria go after ravaging Dominica. This is the latest heat map from various forecast models and GFS ensemble track guidance for Maria. The GFS goes up to 10 days.

Once Maria passes Dominica, Maria may go over St. Kitts, Nevis, Montserrat, U.S. Virgin Islands, British Virgin Islands, and Puerto Rico. Those areas have been ravaged by Hurricane Irma. They do not need another monster hurricane ravaging them again. Some of the forecast models put it over Puerto Rico sometimes by this Wednesday. If Maria goes over Puerto Rico, it would be a very bad disaster for the island, which is mired in a financial crisis. That will make things much worse than it is. After Puerto Rico, most forecast models have Maria going northwestward. Some have it going to the Bahamas. At this point, Maria should not be a threat to the Gulf of Mexico. That can change of course. Not something we need after Harvey and Irma. The next question is how strong will Maria be.

Most forecast models show Maria weakening to Category 4 within 36 hours. Intensity forecast is notoriously difficult. It is possible Maria could be a Category 5 hurricane by the time it hits Puerto Rico. That will make things much worse as it is. Most forecast model a weakening trend as it turns northwest. The waters north of Puerto Rico are cooler due to Hurricane Irma.

Hurricane Irma became a Category 5 in warm waters, not the warmest. The warmest waters are in the Western Caribbean between Cuba, Central America, and Yucatan Peninsula. If Maria went over that water, it would probably be more intense than Wilma in 2005.

Another hurricane I am watching is Jose. It is off the Eastern Seaboard of America. Where it goes is rather complicated. This also complicates on where Hurricane Maria ultimately goes. This is the latest heat map from various forecast models and GFS ensemble track guidance for Jose. The GFS goes up to 10 days.

The forecast models are all over where Hurricane Jose goes. Looks like Jose is likely to linger over the Atlantic. Some have it going towards Florida or New Jersey. The heat map suggests this is a low confidence forecast. Since Jose is at a more northern latitude away from the tropics, it has gotten larger as energy is spread out more.

Hurricane force winds are up to 115 miles 184 km 100 nautical miles across from northwest to northeast quadrant. There is no hurricane force winds on the southern half of Jose. Tropical storm force winds are up to 449 miles 718 km 390 nautical miles from northeast to southeast quadrant. This a lop sided hurricane. Here is the most recent intensity forecast for Jose.

Most forecast models have Jose weakening into a tropical storm in the next five days. Jose will likely become extratropical in the several days. Hurricane Jose does not look like a hurricane from satellite.

Looks more like an extratropical storm than a hurricane to me.

Here is what I think will happen.
-Maria could pose a major threat to Puerto Rico.
-Jose is likely to linger over the Atlantic.

The forecast models came from NCAR-Tropical Cyclone Guidance, NOAA Tropical Cyclone Imagery – Storm Floaters, National Hurricane Center, Tropical Cyclone Heat Potential, and Meteo-France. Special thanks to all of them.

Tres Huracanes

It is going to be a long night for Grand Inagua in the Bahamas. They are getting pelted by strong winds, heavy rain, high waves, and deadly storm surge. Irma has maximum sustained winds of 165 mph 264 km/h 144 knots with gusts as high as 235 mph 376 km/h 204 knots.

The central pressure is 920 millibars, which has risen. This is due to eyewall replacement cycle. Once it is done, Irma would get larger and stronger, which is worse. The update is from National Hurricane Center (NHC).

Irma is quite a large hurricane. The whole Bahamas is going to be ravaged by Hurricane Irma. The Bahamas could see storm surge of up to 20 feet/6.1 meters or greater. Bahamas is mostly flat. So anyone there should seek higher ground now!

The satellite image is quite impressive. I would not want to be caught under Irma right now. The question now is where does Irma go. Here is the latest heat map from various forecast models and GFS ensemble track guidance for Irma. The GFS goes up to 10 days.

The forecast models have Irma going west-northwest. It could make landfall or not on Cuba and than turn north into Florida. The question is where would Irma make landfall. If it makes landfall around Florida Keys or near Miami, it will be really bad. If Irma traverses over Florida, it would ravage Florida with strong winds, heavy rain, high waves, and deadly storm surge. That would be really bad. Another scenario is Irma stays offshore of Florida and makes landfall on Georgia or South Carolina. These are all just scenarios for Florida. The forecasts models are in consensus that Florida could be affected by Irma over the weekend. Anyone who is living in evacuation zones need to evacuate now! This is no game! Unfortunately, many cannot escape as gasoline has ran out at many gas stations. They would have to go another gas station and that is no picnic for sure. Waiting in long lines to get gasoline.

Since Irma has been a Category 5 hurricane since Tuesday, will Irma be still a Category 5 hurricane by this weekend?

Most forecast model keep Irma as a Category 5 by tomorrow. Some weaken it to Category 4 in 24 hours. Most keep Irma as a Category 5 for 36 hours. I think Irma will remain a Category 5 hurricane as it gets closer to Cuba and Florida. Here is why I think this.

The waters ahead of Hurricane Irma are very warm and deep. They have lots of energy for Irma to feed off of. The deep warm water is more favorable for maintaining and intensifying Irma. We have a long way to go when it comes to intensity forecast. Even if Irma weakens to Category 4, the NHC forecasts Irma becomes a much larger hurricane, which makes it more dangerous.

The warm waters can make Irma larger as it undergoes eyewall replacement cycle. A larger Hurricane Irma, even as Category 3 or 4 is very dangerous because it can produce higher storm surge and waves. Case in point, Hurricane Katrina in 2005. Katrina made landfall as Category 3 on Louisiana and Mississippi. It produced storm surge as high as 35 feet/10.7 meters! Hurricane Camille made landfall in the same area as a Category 5 hurricane, but produced storm surge of 25 feet/7.6 meters. Camille was smaller than Katrina. Hurricane Ike is another example of a large hurricane, which made landfall on Texas as a Category 2 hurricane in 2008. Ike produce storm surge as high as 25 feet/7.6 meters, which is highest outside of Mississippi! Hurricane Sandy made landfall as a Category 1 hurricane on New Jersey in 2012. It produced storm surge as high as 15 feet/4.6 meters.

If Irma is the only threat in the Atlantic, there is also Jose and Katia. Let’s start with Jose. Jose is now a major hurricane with 120 mph 192 km/h 105 knots with gusts as high as 150 mph 240 km/h 130 knots.

The forecast model is concerning as that Jose could affect the same areas ravaged by Irma. There is a Hurricane Watch for Antigua, Barbuda, Anguilla, Sint Maarten, and St. Martin. They have been utterly leveled by Irma. Jose would make things worse as they already are. Here is the intensity forecast model for Jose.

Some of the forecast models have Jose becoming a Category 4 hurricane. I think Jose has a chance at being a Category 4 hurricane by tomorrow. It is far away from Irma to not be affected.

Closer to Texas, there is Hurricane Katia in the Southern Gulf of Mexico. Katia is a Category 1 hurricane with 85 mph 136 km/h 74 knots winds with gusts as high as 106 mph 170 km/h 92 knots. Here is a forecast model for Katia.

Most of the forecast models have Katia going towards Mexico. It is unlikely that Katia will turn northwards towards flood ravaged Texas. That is a good thing for sure. The next question is how strong will Katia get?

Only one forecast model has Katia as a Category 3 hurricane, which would be the fourth major hurricane in 2017. Most have Katia peaking at Category 2. I think it has a chance of being a Category 3 hurricane. The area where Katia is over is warm, so it could further intensify. It is also a small hurricane, so it can intensify more quickly.

This is an ever changing event. The forecast is subject to change. Regardless, be prepared!

Here is what I think will happen.
-Irma could affect Florida this weekend
-Jose could pose a threat to Irma ravaged Antigua, Barbuda, Anguilla, Sint Maarten, and St. Martin.
-Katia will make landfall on Mexico.

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