National Hurricane Center

National Hurricane Center Decision Support Services for the United States Coast Guard

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United States Coast Guard Cutter (image courtesy of uscg.mil)

Semper Paratus (Always Ready): A Shared Mission of Watching Over a Vast Blue Ocean

The National Hurricane Center (NHC) has the responsibility for issuing weather forecasts and warnings for a wide expanse of the Atlantic and eastern North Pacific Oceans.  Within NHC, the Hurricane Specialist Unit (HSU) issues forecasts for tropical storms and hurricanes in these regions, issues associated U. S. watches and warnings, and provides guidance for the issuance of watches and warnings for international land areas.  NHC’s Tropical Analysis and Forecast Branch (TAFB) makes forecasts of wind speeds and wave heights and issues wind warnings year-round for the eastern North Pacific Ocean north of the equator to 30°N, and for the Atlantic Ocean north of the equator to 31°N and west of 35°W (including the Gulf of Mexico and Caribbean Sea).  These wind warnings include tropical storms and hurricanes as well as winter storms, tradewind gales, and severe gap-wind events (for example, the “Tehuantepecers” south of Mexico).

The United States Coast Guard (USCG) has areas of responsibility (AORs) that extend well beyond those of NHC, with potential weather hazards affecting the fleet and their missions over the ocean, inland U.S. waterways, and flood-prone U.S. land areas. Although the USCG is responsible for search and rescue missions that may occur due to weather hazards, they are also vulnerable to severe weather and must also protect their own fleet and crews from these hazards.

USCG Search and Rescue Regions (SRRs) cover vast ocean areas affected by tropical cyclones. Superimposed on the Pacific SRRs is the NHC tropical cyclone area of responsibility, which overlaps with two eastern Pacific USCG SRRs as well as all Atlantic SRRs. The number of briefings provided by NHC to each USCG district in 2018 are shown. (Map images courtesy of uscg.mil)

One of the USCG’s oldest missions and highest priorities is to render aid to save lives and property in the maritime environment.  To meet these goals, the United States’ area of search-and-rescue responsibility is divided into internationally recognized inland and maritime regions.  There are five Atlantic USCG Search and Rescue Regions (SRRs) (Boston, Norfolk, Miami, New Orleans, and San Juan) and two Pacific USCG SRRs (Alameda and Honolulu) that overlap with NHC’s hurricane and marine areas of responsibility. The other eastern Pacific regions north of the Alameda SRR do not typically, if ever, experience hurricane activity. The multi-million square mile area of the agencies’ overlap allows NHC to provide weather hazard Decision Support Services (DSS) for the USCG.

Building Partnerships with the Districts

The National Weather Service (NWS) signed a Memorandum of Agreement (MOA) with the USCG to provide them with weather support. Over the past couple of years, staff at NHC have had numerous discussions with several of the USCG districts in order to build stronger partnerships. These discussions, primarily involving how NHC can better serve the USCG, established criteria for requiring TAFB to provide weather briefings to key decision makers within the USCG. When criteria are met, TAFB provides the relevant USCG District with once- or twice-a-day briefing packages detailing the weather impacts on their area of responsibility. This information provides the USCG districts with the details necessary to make efficient and effective decisions about potential mobilization of their fleet.

Example of a briefing slide of NHC’s earliest reasonable arrival time of tropical-storm-force winds graphic, which is one of the USCG’s most-desired decision support tools provided by NHC.  This example, from Hurricane Michael, illustrates the timing of the earliest reasonable onset of tropical-storm-force winds at a given location. This information is critical for fleet mobilization, as once these winds arrive preparations become difficult, if not impossible, to complete.

2018 Hurricane Season Briefing Support

During the 2018 hurricane season, TAFB provided 30 briefings to USCG Districts 5 (Norfolk), 7 (Miami), 8 (New Orleans), and 11 (Alameda) for the several tropical storms and hurricanes that affected them. These interactions helped to build the relationships between NHC and the USCG districts and aided the districts in making decisions regarding fleet mobilization, conducting search and rescue missions, and preparation for USCG’s land-based assets and personnel. Some of these briefings occurred during rapidly evolving high impact scenarios, including Hurricane Michael. Michael was forecast to become a hurricane within 72 hours of developing into a tropical depression and was forecast to make landfall within 96 hours of its formation. Ultimately, Michael rapidly intensified into a category 5 hurricane only 3½ days after formation, before making landfall on the Florida Panhandle. Hurricane Michael’s track across the east-central Gulf of Mexico straddled the border of USCG Districts 7 (Miami) and 8 (New Orleans), leading to both Districts taking action in advance of the hurricane.

Support for District 5 (Norfolk)

The NWS’s Ocean Prediction Center, the NHC (through TAFB), and the NWS National Operations Center have worked together to provide weekly high-level coordination briefings to USCG District 5 on upcoming hazards focused on the Atlantic Ocean north of 31°N over the following seven days.  Each Monday (except Tuesday if Monday is a holiday) by noon Eastern Time, the NWS provides a briefing that covers the mid-Atlantic region from New Jersey through North Carolina.  Typically, the briefing covers the area to roughly 65°W, though the exact area covered can vary based on the week’s expected weather hazards.  The USCG, in turn, has been sharing the information with mariners, port partners, and industry groups for situational awareness and critical decision-making.

Future Support

NHC’s TAFB is ready to provide decision support services to the USCG Districts for the 2019 hurricane season. Plans are being developed to continue this type of support for many years to come.

— Andy Latto
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Hurricane Andrew: Working in a Category 5 Storm

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Infrared satellite image of Hurricane Andrew at 5 AM on August 24, 1992, as it was making landfall along the coast of Miami-Dade County, Florida.

The hurricane season had yet to see its first named storm in August 1992, but that changed dramatically with the arrival of Hurricane Andrew.

South Florida and NOAA’s National Hurricane Center in Coral Gables took a direct hit from Andrew.

We’re going to take you behind the scenes for a glimpse of what it was like to be on duty during that fateful week twenty-five years ago.

The disturbance that had rolled off the coast of Africa became Tropical Storm Andrew on Aug. 17. But three days later, it almost disappeared.

Water vapor satellite image of Tropical Storm Andrew on August 19, 1992, while it was struggling to survive northeast of the Lesser Antilles.

“It looked like the storm had dissipated, but we hung onto it just a little bit longer”, said hurricane forecaster Dr. Richard Pasch, who was working the midnight shift. “The aircraft couldn’t locate the center, and Bob Sheets, the NHC director, came in and I told him I don’t think it’s going away. Bob said ’I don’t either‘, so we went ahead and hung onto it.”

It was a wise decision.

Just two days later, the Hurricane Hunter aircraft found a lower air pressure and better organization. On Saturday morning August 22, they found hurricane-force winds.

Hurricane forecaster Dr. Lixion Avila was on the morning shift.  “In the 5 a.m. advisory, I made Andrew a hurricane. I called Director Bob Sheets, and he said ‘OK, I’ll be there in one hour.’”

Public Advisory issued by Hurricane Specialist Lixion Avila at 5 AM on Saturday, August 22, 1992, making Andrew the first hurricane of the 1992 hurricane season.
Forecast discussion issued at 5 AM on Saturday, August 22, when Andrew was designated as a hurricane.

 

 

 

 

 

 

 

 

 

 

 

Later that same day, Hurricane Research Division (HRD) scientists James Franklin and Dr. Mark DeMaria boarded the NOAA Hurricane Hunter WP-3D aircraft in San Juan as part of a dropwindsonde mission to better sample the winds around the hurricane. The mission ended in Miami about midnight and both went to NHC to see if the new data had an impact on the forecast models. “The models now showed Andrew’s path much farther south and a direct threat to Miami-Dade County,” said DeMaria who, along with Franklin, would go on to become part of the NHC management.

Satellite image of Hurricane Andrew on Sunday, August 23, 1992, as it was headed toward the Bahamas and South Florida.

Andrew continued to rapidly strengthen as it approached South Florida.

In the pre-dawn hours of August 24, its eye, with winds screaming at more than 155 mph around it, neared the Dade County coastline.

Hurricane forecaster Dr. Ed Rappaport recalled how tense that night was, but he and many others were oblivious to the chaos outside. They were all focused on the analysis and typing out the 5 a.m. advisory with the updated forecast and warnings.

Hurricane Specialist Dr. Ed Rappaport prepares the 5 AM August 24 advisory for Hurricane Andrew, with the help of Hurricane Specialists Hal Gerrish, Dr. Richard Pasch, and Max Mayfield, as the hurricane rages outside.
Public advisory for Hurricane Andrew issued at 5 AM on Monday, August 24, as the hurricane’s eye was moving onshore in southern Miami-Dade County.

 

 

 

 

 

 

 

 

 

 

 

 

“When the advisory went out, somebody came up to me and said, ‘What do you think?’ I said, ‘about what?’ And he said ‘Well, the building’s swaying!’  A few minutes later, the anemometer measured a wind gust to 164 mph,” Rappaport said.

And then there was the time the whole building shook.

No one knew what it was, but NHC radar meteorologist Martin Nelson noticed the Miami radar, a WSR-57 (Serial #1), quit working.

“We believe another antenna broke loose and hit the fiberglass dome. Once that happened, the actual radar antenna was exposed,” Nelson said.

Part of that dome fell and landed on top of his pickup truck, while many other dome parts were blown down U.S. Highway 1. Radar fixes of Andrew’s trek over South Florida were captured by the new Doppler radar in Melbourne, Florida.

Radar on top of the building in Coral Gables that housed the National Hurricane Center at the time, destroyed by Hurricane Andrew’s winds.

The day before Andrew made landfall, several NHC forecasters were sent to NOAA’s National Meteorological Center in Maryland to back up NHC just in case it was needed.

One of those forecasters was Hugh Cobb. He was taking a break in his hotel room hours after Andrew made landfall and turned on CNN where the newscaster was talking about damage to the hurricane center.

“I happened to glance up and I saw an image of my car. Apparently there was a blue car that was tossed on top of my car.”

Cars at the National Hurricane Center damaged by Hurricane Andrew. The car in the lower right of the image was owned by forecaster Hugh Cobb (now the branch chief of the Tropical Analysis and Forecast Branch), who was deployed to the National Meteorological Center in Maryland in case NHC needed to be backed up.

Several other employees lost their cars. Worse, two dozen NHC and HRD employees had suffered major damage to their homes. Seven of those homes were destroyed.

NHC moved into a new single story facility three years later, well inland on the campus of Florida International University. Herb Saffir, a structural engineer, had a hand in the fortified design of the building. If the name sounds familiar…he is the “Saffir” in the Saffir-Simpson Hurricane Wind Scale.

Construction of the new National Hurricane Center and Miami-South Florida Weather Forecast Office in 1995 on the campus of Florida International University in the western portion of Miami-Dade County.

When another hurricane strikes, especially one with the power of Andrew, things will be different.

“We’ve got a plan in place for a hurricane landfall here in Miami, and we have successfully exercised it a few times, including when 2005’s Hurricane Katrina and Hurricane Wilma hit us,” said Rappaport, who is now the acting NHC Director.  “We’ve got the shutters and other essentials here to provide protection…as we try to impress upon the public to do the same.”

— Dennis Feltgen, NOAA Communications and Public Affairs Officer, National Hurricane Center

The View from Inside the Eye

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HurricaneCenter
The National Hurricane Center and Miami National Weather Service Forecast Office, located on the campus of Florida International University in Miami, Florida.

 

Welcome to “Inside the Eye,” the official blog of the National Hurricane Center!

 

http://en.wikipedia.org/wiki/File:Hurricane_Katrina_Eye_viewed_from_Hurricane_Hunter.jpg
View of the eyewall of Hurricane Katrina taken on August 28, 2005, as seen from NOAA WP-3D Orion hurricane hunter aircraft before the storm made landfall on the United States Gulf Coast.

Why have we launched a blog?  The staff at the National Hurricane Center (NHC) regularly conducts training and educational workshops during the off season for specific audience groups, including emergency managers and other meteorologists.  However, despite our heavy emphasis on outreach, there is always a large segment of the population that does not have the opportunity to hear from us in person on important changes to NHC products or discuss topics related to tropical and marine weather events.  Therefore, we’ve launched this blog to be able to keep you, our partners and customers, more informed on a consistent and timely basis.

The National Hurricane Center has long had a vision of being America’s “calm, clear and trusted voice in the eye of the storm.”  Much like the NOAA Hurricane Hunter aircraft in the picture to the right, we also want you to have a view from inside the eye.  We want you to see what’s happening at the Hurricane Center before, during, and after a storm.  We also want to help you understand how to interpret our forecasts so that even when there is a hurricane, you will have a clear understanding of what to expect and plan for.

Stay tuned for blog posts in the coming weeks.  We have some big forecast product launches coming up this hurricane season, including an experimental potential surge surge flooding map and an extended 5-day graphical tropical weather outlook, and we plan to use the blog to provide information on the background and interpretation of these products.  In addition, our staff has a wide range and diversity of expertise, so you can expect to see blog posts on many different subjects as we go forward.  You may even see an occasional guest blog post from experts outside of NHC.

If you’d like to follow our blog and receive updates on blog posts, you can sign up to receive email notifications at the bottom of the column on the right.  We also plan to advertise new posts on our various Twitter and Facebook accounts.

— Robbie Berg