Kirk And Leslie Evidence That Satellites Are Still Important To Tropical Forecasting

Hurricane Kirk has an impressive size, with tropical storm-force winds extending over 200 miles from the storm’s center.

Tropical storm Leslie is smaller, but still strong, just over 1,000 miles away from Hurricane Kirk.

A hundred years ago, forecasters may not have known these storms even existed.

The History Of Tropical Detection And Observation

Prior to the development of satellites, hurricanes could only be monitored by direct observations.

In the 1870s, Father Benito Vines, the director of the Meteorological Observatory of the Royal College of Belén in Cuba, established the first network of observation sites focusing on hurricane detection. The United States began establishing its own observing stations throughout the Caribbean during and after the Spanish-American War in the late 1890s.

The problem with land-based observation stations is that a tropical system must have observable impacts to land in order to be detected.

Real-time observations took to the sea starting in the early 1900s with the development and use of the wireless telegraph on ships, which alowed to relay information about weather conditions in the ocean directly to forecasters on land.

Ships were able to relay information about weather conditions in the ocean directly to forecasters on land.

The first recorded planned flight into a hurricane was in July 1943, “when two Army Air Corps pilots challenged each other to fly through a hurricane,” according to the U.S. Air Force 403rd Wing.

(​MORE: 80 Years Ago, Hurricane Hunting Began With A Bet)

The flight was into a storm near Galveston and is regarded as the first mission of what we now know as the U.S. Air Force Hurricane Hunters.

However, that flight was only conducted because people on land already knew there was a storm there.

The first hurricane seen from space: It wasn’t until September 10, 1961, two months after the launch of the TIROS III satellite, that the first tropical system was initially detected by satellite without any direct, in-situ observations.

The TIROS III satellite detected “an area of disturbed weather a hundred miles southwest of the Cabo Verde Islands,” explains NOAA’s Atlantic Oceanographic & Meteorological Laboratory.

One day later, the satellite and ships in the area detected circulation, and the storm was officially named Hurricane Esther on September 12 after a reconnaissance aircraft found hurricane-force winds.

Six years later, Hurricane Camille, one of the strongest hurricanes to ever impact the mainland U.S., was under continuous surveillance by the Nimbus-3 satellite from its first detection on August 14, 1969, to landfall on August 17.

Satellite imagery “was particularly valuable in tracking Camille across the tropical North Atlantic from Africa,” says a report on the storm by the Environmental Science Services Administration from September 1969.

“It was a valuable tool in directing the aerial reconnaissance flights into the right areas and provided good estimates of Camille’s position at times of doubtful aerial fixes.”

Geostationary satellites were later introduced in 1975. Geostationary satellites are able to orbit the Earth at a speed allowing them to stay fixed over the same area of the planet and creating a continuous monitoring system for tropical development.

Today, NOAA owns and operates five geostationary satellites, called Geostationary Operational Environmental Satellites (GOES).

There are a total of 23 geostationary satellites orbiting earth, so near-continuous satellite imagery is possible world-wide.

It is through these satellites that the National Hurricane Center is watching Hurricane Kirk and Tropical Storm Leslie.

Satellites: Tropical Forecaster’s Not-Secret Weapon

Even though they are likely to be fish storms, Kirk and Leslie can still cause disruptions to shipping routes, and Kirk may cause life-threatening swells and currents for Bermuda and the Leeward Islands.

Because we have satellite images of the storms, ships can adjust their routes to avoid dangerous conditions.

Forecasts are also better thanks to satellites watching the tropics, especially with modern imaging technology that can make observations beyond just what the storm looks like.

GOES satellites are able to measure a storm’s current conditions, like cloud height and convective activity, and then monitor how the storm is changing over time. Is it weakening? Is it strengthening? How fast?

Forecasting is improved even more because satellites take detailed measurements of factors that can impact a storm’s development and track.

Factors like water temperature, moisture and wind shear all play an important part in tropical forecasting, and satellites can provide the data without an endless network of observation stations throughout the ocean.

For example, when Hurricane Kirk was first being watched as an interest area by the National Hurricane Center, this line was included in the discussion on the NHC website:

“Environmental conditions are expected to be conducive for slow development thereafter while the system moves generally northwestward at 10 to 15 mph.”

Many of those environmental conditions are measured via satellite, and communication satellites help relay information from ocean buoys and fleets of robotic instruments capable of diving underwater.

An Early, And Accurate, Warning System

Before satellites, not only were forecasts hampered by a lack of data - some storms were “missed” entirely, and forecasters and the public never knew there was a storm at all.

Researchers have estimated that an average of one tropical storm was missed per four years before we entered the “satellite era.” The number of missed storms was worse for 1880 with an estimated 3.4 storms per year on average.

Storms that do have impacts to land can also be reliably tracked much sooner than they would have been 100 years ago.

The Great Galveston Hurricane of 1900 hit Galveston, Texas, with little to no prior warning and no knowledge that it was in the Gulf of Mexico.

When Hurricane Camille made landfall in Louisiana in August of 1969, its exact location had been continuously tracked by satellite, allowing for more preparation and more lives saved.

Sara Tonks is a content meteorologist with weather.com and has a bachelors and a masters degree from Georgia Tech in Earth and Atmospheric Sciences along with a masters degree from Unity Environmental University in Marine Science.