Tropical Storm Hernan developed over this past weekend and reached hurricane strength before vertical wind shear kicked in and kicked the storm down.
NASA's Terra satellite passed over Hernan when it was developing as a tropical depression near Baja California, Mexico.
Tropical Storm Hernan was born on Saturday, July 26 at 5 a.m. EDT as Tropical Depression 8-E. By 5 p.m. EDT it strengthened into Tropical Storm Hernan. At 11 a.m. EDT on Sunday, July 27, Hernan's maximum sustained winds were already up to 70 mph, just four miles per hour shy of hurricane status.
As Hernan passed west of Socorro Island at 5 p.m. EDT on July 28 it reached hurricane status when its maximum sustained winds reached 75 mph (120 kph). It remained a hurricane for about 12 hours before dropping back to a tropical storm on July 29 at 5 a.m. EDT when maximum sustained winds were near 70 mph (110 kph).
Hernan moved into an area of persistent westerly wind shear blowing at between 15 to 20 knots (17.2 to 23.0 mph/27.8 to 37.0 kph). That wind shear is deteriorating the cyclone's organization.
Infrared satellite data from instruments like the Atmospheric Infrared Sounder (AIRS) aboard NASA's Aqua satellite showed that the cloud top temperatures were warming. Warming cloud tops means that the uplift of air had weakened.
Uplift is air that pushes thunderstorms into the top of the troposphere. The higher the thunderstorm cloud top, the colder it is (because the troposphere cools as you go higher). Higher, colder cloud tops in thunderstorms mean stronger thunderstorms.
Visible satellite data today indicated "a rather shapeless cloud pattern," according to the National Hurricane Center. That means the circulation is less organized.
At 11 a.m. EDT (1500 UTC) on July 28, Tropical Storm Hernan's maximum sustained winds were down to 65 mph (100 kph). It was centered near 20.5 north latitude and 115.9 west longitude, about 420 miles west-southwest (675 km) of the southern tip of Baja California. Hernan is moving toward the northwest near 16 mph (26 kph) and is forecast to continue through Tuesday night, July 29, followed by a turn to the west.
Forecaster Roberts at the National Hurricane Center noted today, July 28 that in addition to being battered by wind shear, "an increasingly stable air mass and decreasing sea surface temperatures should ultimately weaken Hernan into a shallow post-tropical cyclone in 48 hours."
Rob Gutro | Eurek Alert!
New research calculates capacity of North American forests to sequester carbon
16.07.2018 | University of California - Santa Cruz
Scientists discover Earth's youngest banded iron formation in western China
12.07.2018 | University of Alberta
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
16.07.2018 | Life Sciences
16.07.2018 | Earth Sciences
16.07.2018 | Physics and Astronomy