A New Normal Part 2

We are living in a new world and reality, a post-Harvey Texas. Just a week ago, a Category 4 monster, Hurricane Harvey was barreling down towards Rockport. Harvey was the first major hurricane to make landfall on America since Wilma in 2005. I think the National Hurricane Center (NHC) may increase Harvey’s peak to 140 mph 224 km/h 122 knots hurricane. Harvey being the first major hurricane to make landfall since Wilma has been largely overshadowed by the epic flooding that ravaged Houston and Beaumont area. That started on the night of August 26, 2017. A series of core rains that form near the center of Harvey.

One good news, the area of thunderstorms in the Southwest Gulf of Mexico does not pose a threat due to wind shear. It is an area of thunderstorms from a tropical wave. However, a cold front that is passing to Southeast Texas could set off thunderstorms and more rain as it picks up moisture from the tropical wave per NWS Houston.

000
FXUS64 KHGX 020220
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
920 PM CDT Fri Sep 1 2017

.UPDATE...
Forecast for tonight looking on track. Updated temps and
dewpoints for trends.

Beat

&&

.PREV DISCUSSION... /ISSUED 628 PM CDT Fri Sep 1 2017/

AVIATION...
Sea breeze and outflow boundary are working their way inland with not
a whole lot of wind changes. SHRA activity that did develop late this
afternoon has now moved away from LBX. Look for light and variable
winds overnight with some patchy MVFR fog possible again at CXO. Expect
VFR conditions tomorrow with mainly light and variable winds. 42

PREV DISCUSSION... /ISSUED 343 PM CDT Fri Sep 1 2017/

DISCUSSION...
Current satellite is showing the typical afternoon cumulus field
developing across southeast Texas. There is a little enhanced
cumulus along the coast but the weak seabreeze is having trouble
generating enough lift for anything more than very isolated and
weak showers. This is expected again tomorrow and the dry weather
is greatly appreciated.

Models are still showing an upper level trough dropping into North
Texas tomorrow night though a significant change is a stronger
ridge over the southern Plains pinching the trough off from the
westerly flow and retrograding it back to the southwest earlier
than previous model runs. A more westerly position of this trough
means weaker lift and lower PoPs for Saturday night and Sunday.

Tropical moisture in the southern Gulf of Mexico will move north
early next week giving us our next decent chance for rainfall. At
the same time, a western U.S. ridge will amplify and northerly
upper flow will drive a cold front through the area Tuesday night
and early Wednesday. The tropical moisture already in place will
interact with this cold front producing a line of showers and
storms along the front. Fortunately the cold front will be moving
fairly quickly, especially for this time of year, pushing the rain
south by Wednesday afternoon. Behind the front, cool and dry air
will filter into the area bringing very pleasant temperatures with
highs only in the lower 80s Wed/Thu.

Hennig

There is also a tropical wave in the far eastern Atlantic that has a good chance of becoming Jose in the next five days. My main concern is Hurricane Irma, which is a Category 3 hurricane out in the Atlantic. Many are wondering where will Irma go. The latest heat map from various forecast models and GFS ensemble track guidance. The GFS goes up to 10 days.

Most forecast models have Irma moving west southwest direction in the next 5 days. From there, based on GFS ensembles, it could go anywhere. Some have Irma going into the Gulf of Mexico and hitting Louisiana in 10 days. Some have Irma hitting Florida to New York. This is too early too tell and this a low confidence forecast. Anything can happen between now and around September 11, which is the 16th anniversary of horrifying terrorist attacks that killed 3,000 people and destroyed the World Trade Center.

Many on social media may have seen this.

That is bogus. For one, the NHC does not issue forecasts 13 days in advance. They only go up to 5 days in advance. Nobody knows where Irma or any hurricane will go in the next 10 days, let alone 5 days.

The latest intensity forecast are in general agreement that Irma will be a major hurricane. A couple have Irma as a Category 2 fluctuating as Category 3, which happens due to eyewall replacement cycle.

I would not be surprised if Irma becomes a Category 5 hurricane, especially when it gets around the Caribbean. Hurricanes in that part of the Atlantic rarely become Category 5 hurricanes. Irma will have to be watched for September.

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A New Normal Part 1

Texas and Louisiana are slowly recovering from the ravages of Harvey. It is a national tragedy. Harvey is now a tropical depression over Mississippi dumping heavy rain over Alabama, Mississippi, and Tennessee. They have seen 5 to 8 inches/12.7 to 20.3 centimeters of rain so far. Flooding continues to be a problem for many areas. The Addicks and Barker Reservoir are still bursting at the seams with too much water.

The death toll as of 8/31/2017 is nearly 40. I suspect the death toll is going to be much higher once the flood water recedes. The question is how many. Too early to speculate at this time. If I had to guess, it could be in the hundreds. Katrina claimed more than 1,800 lives, while 9/11 claimed 3,000 lives. 9/11 is a terrorist attack. Harvey could be the deadliest natural disaster since Katrina.

With Harvey no longer a problem, I turn my attention to three areas in the tropics. There are two areas that need to be watched, Hurricane Irma, a low pressure in the Gulf of Mexico, and tropical wave emerging from West Africa. Let’s start with Irma.

Irma is now a major hurricane with 115 mph 184 km/h 100 knots with gusts of 145 mph 232 km/h 126 knots. It is moving westward at this time. Many are wondering where will Irma go. Will Irma enter the Gulf of Mexico, make landfall on the East Coast, or become a fish storm? The latest heat map from various forecast models and GFS ensemble track guidance. The GFS goes up to 10 days.

The forecast models at this point do not have have it getting close to Texas. Some have Irma entering the Gulf of Mexico and hitting the Florida Panhandle. It looks to be a East Coast threat at this point. New York City area is included in the risk area. Again, this is 10 days from now and anything can change between now and next week. Since Irma is a major hurricane, the intensity forecast is interesting.

Most maintain Irma as a Category 3 hurricane. One has it as Category 4 hurricane in two days. Some have Irma as a Category 4 hurricane in three days. I think Irma has the potential to intensify into a Category 5 hurricane, especially when it gets closer to the Caribbean. Irma could be a problem starting next week as it gets closer to land. Irma needs to be watched closely.

Another area of concern is in the Southwest Gulf of Mexico. Here is a discussion from National Hurricane Center (NHC)

ZCZC MIATWOAT ALL
TTAA00 KNHC DDHHMM

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 PM EDT Thu Aug 31 2017

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

The National Hurricane Center is issuing advisories on Hurricane
Irma, located over the eastern Atlantic Ocean. The Weather
Prediction Center is issuing advisories on Tropical Depression
Harvey, located over northern Mississippi.

1. A tropical wave emerging over the far eastern Atlantic is moving
westward at about 15 mph. Environmental conditions are expected to
become more conducive for development over the weekend and early
next week while the system moves well to the south and southwest of
the Cabo Verde Islands.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...medium...40 percent.

2. A area of low pressure could form over the southwestern Gulf of
Mexico by the weekend, however, environmental conditions are
expected to become unfavorable for tropical cyclone formation by
that time. Interests along the Texas and Louisiana coasts are
encouraged to consult products from their local NWS Forecast Office
for more information about impacts from any non-tropical weather
systems.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...low...10 percent.

Public Advisories on Harvey are issued under WMO header WTNT34 KWNH
and under AWIPS header TCPAT4.

Forecaster Zelinsky

I do no think that will develop into something tropical. However, the moisture from it could be a factor for next week as a cold front passes. The cold front could trigger storms in areas that have been flooded. Not a good thing. That will also have to be watched.

Lastly, there is a tropical wave emerging out of West Africa. I think it will be tagged with an Invest in the next couple of days. It has a moderate chance of developing in the next five days. I would not be surprised if this becomes our next named storm, which would be Jose.

Here is what I think will happen.
-The area of thunderstorms in Southwest Gulf of Mexico bears watching, but I do not think it will develop.
-Irma needs to be watched and may pose a threat somewhere.
-Tropical wave emerging from West Africa needs to be watched. Could be Jose.

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

This is going to be a long road to recovery. It is a new normal for Texas.

Epic Flood Day 3

The helicopters flying and boats rescuing people from their flooded out homes. A sight all too common in the Houston area. The Addicks and Barker are bursting with so much water that it has be released to avoid catastrophic and widespread flooding at the cost of flooding neighborhoods. It is on the 12th anniversary of Hurricane Katrina making landfall on Louisiana and Mississippi. I am completely overwhelmed by this disaster as a weather buff. Here is a 7 day rainfall total map from Advanced Hydrologic Prediction Service (AHPS). It is unbelievable amounts I have seen.

The rainfall total are from multi-sensor (radar and rain gauge) precipitation estimates obtained from National Weather Service (NWS) River Forecast Centers (RFCs) and mosaicked by National Centers for Environmental Prediction (NCEP). There are areas that have gotten over 50 inches/127 centimeters of rain. Some areas have nearly gotten 60 inches/152.4 centimeters of rain! I would not be surprised by the end of the week, some areas get up over 60 inches/152.4 centimeters of rain!

Another mind boggling aspect is the large area that received heavy rains.

The green is where at least 10 inches/25.4 centimeters of rain fell. A large area received at least 10 inches/25.4 centimeters or greater! This has to go down as one of the largest rain events in America. We should know once Harvey passes. In the meantime, East Texas and Southwest Louisiana is getting hit by heavy rain. The latest Doppler radar out of NWS Lake Charles shows heavy rain as the storm is over the Gulf of Mexico.

Here is the 24 hour rainfall forecast from GFS, Canadian, EURO, and Weather Prediction Center (WPC).

The forecast models have the heaviest rains east of Houston. This time it is over East Texas and Southwest Louisiana. They have been getting plenty of heavy rain as well.

GFS: 11 inches/27.94 centimeters
Canadian: 10 inches/25.40 centimeters
EURO: 15 inches/38.10 centimeters
WPC: 10.74 inches/27.28 centimeters

As for Houston area, they could see still see rain, including occasional heavy rain. Looking at more moderate rain for Houston. The heavy rain has shifted to East Texas and Southwest Louisiana. Even New Orleans area is getting heavy rain and there is concern for flooding. Some of the pumps are not working, which could flood again like what happened with Katrina.

The million dollar question is where Harvey goes. Here is a heat map from various forecast models.

There is now a consensus among forecast models that Harvey will go northeast after making landfall on Southwest Louisiana as a tropical storm. Here is the latest from the National Hurricane Center. It is as of 10:00 PM or 2200 CDT:
Location: 29.0°N 93.6°W
Moving: NE at 6 mph 9 km/h 5.2 knots
Min pressure: 994 mb
Max sustained: 50 mph 80 km/h 44 knots

I do not think Harvey will intensify as it makes landfall again as a tropical storm. The reason is the core is a swirl of clouds with no thunderstorms. All the thunderstorms are north and east of the center. Once it makes landfall, Harvey moves quickly to the northeast. I say good riddance to Harvey.

Here is what I think will happen.
-Heavy rain at night, especially near and east of the center, which is East Texas and Southwest Louisiana.
-Not ruling out Houston area getting rain again tonight. Looking not as heavy. More like moderate rain.
-Rainfall amounts could range from 10 to 15 inches/25.4 to 38.1 centimeters of rain with isolated totals approaching and exceeding 20 inches/50.8 centimeters.

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

I am at total loss of words of with Harvey. I cannot imagine what people are going through. This a disaster that I cannot comprehend. It defies any description.

Epic Flood Day 2

Houston and the surrounding area is under water from the heavy rains of Harvey. So many people are being rescued from their flooded out homes as I type. I am so utterly stunned and horrified at what has been going on. Here is a 7 day rainfall total map from Advanced Hydrologic Prediction Service (AHPS). It is unbelievable amounts I have seen.

The highest is total is over 45 inches/114.3 centimeters! That is over Liberty County. The area of heavy rain is much larger than Allison. Heavy rain from South, Central, and East Texas. This is easily one of the largest flood events in Texas and possibly in American history. Let that all sink in. With more rain forecasted tonight and tomorrow, the total is most certainly going to rise. The forecast of 50 to 60 inches/127 to 152.4 centimeters of rain is not so far-fetched. Let’s look at the ever important rainfall forecast totals up to Friday. They are from GFS, Canadian, EURO, and Weather Prediction Center (WPC).

All of them have more rain coming. The location and amount varies.
GFS: 31 inches/78.74 centimeters
Canadian: 18 inches/45.72 centimeters
EURO: 21 inches/53.34 centimeters
WPC: 17.80 inches/45.21 centimeters

The GFS has the highest, while WPC has the lowest. The GFS and WPC have heaviest rain over Houston area. Canadian has two areas of heavy rain over Houston area and East Texas. The EURO has the heaviest over East Texas. Looks like more heavy rain will fall in the next few days from Harvey. Just the amount and where is the problem.

The million dollar question is where Harvey goes. Here is a heat map from various forecast models.

If there is some good news, the forecast models are on consensus that Harvey is eventually going to move out of Texas. The previous forecast models were low confidences as they were all over the place on where Harvey would go. This time looks Harvey is heading northeastward. However, Harvey is over the Gulf of Mexico, which allows the core to redevelop, which could mean more rain for Houston area. That is a very bad thing. Also, it could allow Harvey to reintensify and head back to land as a tropical storm. Another million dollar question, how strong will Harvey be?

Most forecast models keep Harvey as a tropical storm. Harvey has strengthened somewhat to 45 mph 72 km/h 40 knots. Some have Harvey intensifying, while a couple have Harvey becoming a strong tropical storm. I do no think Harvey will be a hurricane again despite being over the Gulf of Mexico on Tuesday. Let’s hope not.

What will tonight be like? 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 0800Z or 3:00 AM CDT. The RGEM has it at 0900Z or 4:00 AM.

All the forecast models agree that there will be thunderstorms firing up near the center of Harvey. The locations vary by forecast model. HRRR has the heaviest rain over Beaumont area and East Texas. NAM has it over Houston area. RGEM has heaviest rain over Houston and Beaumont area. WRF-ARW has heaviest rain over Texas and Louisiana border. WRF-NMM has heaviest rain northeast of Houston. The WRF-ARW and WRF-NMM have the center of Harvey over land, which is not the case as of right now. Heavy rain is possible again tonight, but the forecast models are split on where it will happen. Like I mentioned before with tropical systems, the thunderstorms flare up at night due to the warm core and cooler surrounding temperature.

Here is what I think will happen.
-Heavy rain at night, especially near and east of the center.
-Not ruling out Houston area getting more heavy rain again tonight.
-Rainfall amounts could range from 5 to 10 inches/12.7 to 25.4 centimeters of rain with isolated totals approaching and exceeding 15 inches/38.1 centimeters.

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

I am at total loss of words of with Harvey. I cannot imagine what people are going through. This a disaster that I cannot comprehend. It defies any description.

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.

Atlantic Hurricane Season In June

As we are in June and hurricane season is heating up. Where do most June tropical storms and hurricanes form and end up going?

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

Most June tropical storms and hurricanes form in the Gulf of Mexico, Southwest Caribbean, and off the Carolinas. No surprise that Texas and Florida are most vulnerable to tropical storms and hurricanes in June.