Hurricane Laura became a named tropical system in the Caribbean at 1500 UTC 21 Aug 2020, and a Hurricane at 1500 UTC 25 August 2020. According to the NHC very early on 27 Aug, “Laura made landfall near Cameron, Louisiana, around 0600 UTC (1 am CDT) with maximum sustained winds of 130 kt, which is near the high end of category 4 status.” The following post includes a collection of GOES ABI imagery captured during the evolution of Laura.
The full evolution of Laura as a named storm through the day after landfall (21-27 Aug) is shown in Figures 1-3 as hourly GOES-East animations. Figure 1 includes 10.3 um IR window channel imagery, while Figure 2 transitions between 10.3 um IR window channel imagery during the night, and VIS-IR Sandwich imagery during the day. Figure 3 characterizes lightning activity during the life of the storm, utilizing GOES-East Flash Extent Density (note, only 5-min GLM FED was used).
A water vapor animation with RAP 500 mb wind and height analyses captures the influencing large scale features during the long trek of Laura. Notably, a broad ridge over the western Atlantic early in the period expands west into the southeast US and eastern GoM throughout the animation, helping to steer Laura west of the track of the preceding Marco, into the western GoM (Fig 4).
A feature relative GOES-East VIS animation during the full day of the 25th depicts the strengthening of Laura from a Tropical Storm to a Hurricane (Fig 5).
Zooming out for the same period, Laura is seen advancing into the central Gulf of Mexico, while remnants of Marco accelerates west along the Louisiana Gulf Coast (Fig 6).
A mesoscale sector was available over Laura during it’s evolution, providing forecasters with valuable 1-min-updating imagery. The final 70 minutes of visible imagery on the 25th capture increasing thunderstorm activity around the center of circulation (Fig 7). One-minute imagery eases diagnosis of a center of circulation in tropical systems, particularly in unorganized storm systems. The evolution of individual convective updrafts associated with the tropical system are also more efficiently tracked in space and time using the high temporal resolution, low latency imagery.
During the overnight hours of the 25h-26th, Laura continued to strengthen, with an eye becoming apparent by the early morning of the 26th per GOES-East IR imagery (Fig 8).
Sunrise over Laura on the 26th revealed a much better organized hurricane with a developing eye, albeit still contaminated with some cloud debris (Fig 9).
A zoomed out view of the full mesoscale sector shows the massive storm approaching the coast (Fig 10). The IR-VIS sandwich combo imagery combines the high spatial detail of the VIS with the quantitative BT information from the IR.
By the late morning of the 26th, the eye had cleared considerably, and low and upper level vorticies could be diagnosed in the 1-min VIS with convective activity still becoming organized within the eyewall (Fig 11).
During the afternoon, eye clearing had completed, convective activity became more consistent within the eyewall, and a healthy major hurricane was apparent (Fig 12).
A clear eye and healthy eyewall were still apparent in 1-min visible imagery as sun set on the storm during the early evening of the 26th, jsut several hours prior to landfall (Fig 13).
The full development of the impressive storm during the day of the 26th is diagnosed in GOES-East visible imagery (Fig 14).
GOES-West provided a unique perspective of the hurricane on the 26th given the much larger viewing zenith angle compared to that of GOES-East (Fig 15).
Landfall of Hurricane Laura in southwest Louisiana was displayed in GOES-East IR imagery during the overnight hours. Imagery shows the large eye remaining intact well inland, before filling in by early morning (Fig 16).
Figure 17 provides a zoomed in look at 2-min IR imagery during landfall, including surface obs.
GOES-East visible imagery after sunrise on the 27th shows the massive storm and lack of clear eye (Fig 18). The weakening tropical system filled most of the 1000 x 1000 km mesoscale sector.
Finally, Day Cloud Phase Distinction RGB imagery from the 27th shows convective activity and upper level clouds (reds and yellows) becoming detached from the low level circulation (cyan/blue clouds; Fig 19).
Bill Line, NESDIS