Irma Science List

But whereas they are important methods of hurricane forecasting, it is the old-fashioned weather balloon—a stalwart of the meteorological world since the 1930s—that can provide some of the most detailed, reliable data on the interlocking puzzle of large-scale weather patterns that ultimately determine where storms like Irma go.

It is an effort to help answer a big question mark that has been hanging ominously over Florida all week as Hurricane Irma creeps closer: What part of the state—if any—will bear the brunt of a hurricane that is one of the strongest ever measured in the Atlantic Ocean, a storm that has already left a trail of destruction across the Caribbean?

On a normal day weather balloons are lofted simultaneously every 12 hours at NWS offices across the country, a schedule that is usually enough to see what the atmosphere is doing, Aberson says.

Each five-foot-diameter balloon carries a small, expendable instrument package that is encased in Styrofoam and measures humidity, temperature and wind as it rises from the ground up to 100,000 feet.

It is an effort to help answer a big question mark that has been hanging ominously over Florida all week as Hurricane Irma creeps closer: What part of the state—if any—will bear the brunt of a hurricane that is one of the strongest ever measured in the Atlantic Ocean, a storm that has already left a trail of destruction across the Caribbean?

But it is expected to take that northward turn courtesy of the pull of a low-pressure trough developing over the eastern U.S.

Irma would turn sooner and might rake the coasts of Florida, Georgia and South Carolina, bringing a devastating storm surge and winds to a densely populated coastline.

One of the last times such an effort occurred was in the lead-up to Hurricane Sandy in 2012, when forecasters were trying to gauge the progression of a cold front that would affect Sandy’s track, says Daryl Williams, a forecaster with the Norman, Okla., NWS office, which is also taking part in the Irma effort.

The technology is nothing fancy.

Forecasters have known for days that Irma is going to turn northward toward the mainland U.S., but they did not know when exactly that would happen—and in this case the “when” makes all the difference for where the storm finally hits, what kind of damage it might do and the ability of officials to order evacuations as early as possible.

One of the last times such an effort occurred was in the lead-up to Hurricane Sandy in 2012, when forecasters were trying to gauge the progression of a cold front that would affect Sandy’s track, says Daryl Williams, a forecaster with the Norman, Okla., NWS office, which is also taking part in the Irma effort.

Irma would turn sooner and might rake the coasts of Florida, Georgia and South Carolina, bringing a devastating storm surge and winds to a densely populated coastline.

But with an uncertain forecast for a potentially historic storm, the National Hurricane Center on Sunday asked several NWS offices to conduct extra balloon releases to get more high-quality data into the models, in the hopes of improving the forecast.

This information gets plugged into weather models to provide the initial conditions for forecasts.

But with an uncertain forecast for a potentially historic storm, the National Hurricane Center on Sunday asked several NWS offices to conduct extra balloon releases to get more high-quality data into the models, in the hopes of improving the forecast.

But whereas they are important methods of hurricane forecasting, it is the old-fashioned weather balloon—a stalwart of the meteorological world since the 1930s—that can provide some of the most detailed, reliable data on the interlocking puzzle of large-scale weather patterns that ultimately determine where storms like Irma go.

Every six hours this week, in a bit of meteorological choreography, dozens of National Weather Service (NWS) offices have been releasing weather balloons in unison.

Although state-of-the-art satellites do continuously monitor that bigger weather picture, they measure things such as wind and water vapor indirectly, based on the wavelengths of light they detect, so they are not as accurate as direct measurements, says Sim Aberson of the National Oceanic and Atmospheric Administration’s Hurricane Research Division.

Irma would turn sooner and might rake the coasts of Florida, Georgia and South Carolina, bringing a devastating storm surge and winds to a densely populated coastline.

Although state-of-the-art satellites do continuously monitor that bigger weather picture, they measure things such as wind and water vapor indirectly, based on the wavelengths of light they detect, so they are not as accurate as direct measurements, says Sim Aberson of the National Oceanic and Atmospheric Administration’s Hurricane Research Division.

Such a large and coordinated effort involving extra launches is fairly rare, usually reserved for hurricanes that could do major damage and come with a particularly uncertain forecast, says Griffin, whose office is participating in the extra releases.

High-resolution images from satellites and the dramatic “hurricane hunter” flights into the category 5 storm get all the glory.

Such a large and coordinated effort involving extra launches is fairly rare, usually reserved for hurricanes that could do major damage and come with a particularly uncertain forecast, says Griffin, whose office is participating in the extra releases.

Forecasters have known for days that Irma is going to turn northward toward the mainland U.S., but they did not know when exactly that would happen—and in this case the “when” makes all the difference for where the storm finally hits, what kind of damage it might do and the ability of officials to order evacuations as early as possible.

Such a large and coordinated effort involving extra launches is fairly rare, usually reserved for hurricanes that could do major damage and come with a particularly uncertain forecast, says Griffin, whose office is participating in the extra releases.