Hurricane Matthew moved through the Bahamas overnight, slowly organizing and strengthening to Category 4 intensity after its interaction with the high terrain of the Greater Antilles (Note that Day/Night Band Imagery from overnight on 6 October — from this Blog Post — shows that city lights are back on in Port-au-Prince Haiti as recovery proceeds in that country). The three images above show the evolution of the storm from 0345 UTC to 1145 UTC on 6 October. A warm eye is present, but it is not a cloud-free eye.

The GOES-13 satellite continued to be in Rapid Scan Operations (RSO) mode, providing images as frequently as every 5-7 minutes. An animation of Infrared Window (10.7 µm) imagery is shown below (MP4 | animated GIF). Nassau, Bahamas (station identifier MYNN) experienced a wind gust of 74 knots at 13 UTC.

A higher-resolution view of the eye was provided by a Suomi NPP VIIRS Infrared Window (11.45 µm) image at 0645 UTC, below.

GOES-13 Visible Imagery from early in the morning on 6 October, below (MP4 | animated GIF), confirms the diagnosis of a cloudy eye. The center of the storm is moving northwestward between Andros Island to the west and New Providence Island to the east (Nassau, the capitol of the Bahamas, is on New Providence Island).

Matthew is forecast to reach the coast of Florida within 24 hours. For the latest information, consult the website of the National Hurricane Center. Additional information is available here.

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The animation of Matthew, above, from morphed microwave imagery (from this site), shows the toll that interaction with the high terrain of Hispaniola and eastern Cuba has had on the storm (causing it to be downgraded from Category 4 to Category 3 intensity). The formerly distinct eye had eroded, although eye re-formation occurs at the end of the animation. Once again, a comparison of microwave vs infrared imagery revealed that the well-defined eye structure was much more apparent using microwave data. Strengthening/Re-organization of Matthew in the near term will be governed by Sea Surface Temperatures (that are warm) and wind shear (shown below, from this site, that is weak).

Total Precipitable Water fields (from this site, using data from here), below, show abundant moisture surrounding Matthew at its present position. There is dry air over the eastern United States landmass, however.

During the morning and afternoon hours, the satellite presentation of Matthew began to slowly improve on GOES-13 Visible (0.63 µm) and Infrared Window (10.7 µm) imagery, below (MP4 | animated GIF), with well-defined convective bursts seen later in the day. Note: the noise seen on the 1645 UTC images was due to solar RFI.

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Hurricane Matthew has made landfall in western Haiti. The rocking animation (click here for a straight animation) above shows the cloud-filled eye of the storm crossing the Tiburon Peninsula. The storm’s center is forecast to remain largely over water as it moves through the Windward Passage between Cuba and Hispaniola.

A closer look using a 2-panel comparison of GOES-13 Visible (0.63  µm) and Infrared Window (10.7 µm) images, below, shows the deteriorating satellite presentation following interaction with the topography of the islands. The GOES-13 satellite was in Rapid Scan Operations (RSO) mode, providing images as frequently as every 5-7 minutes.

NOAA-18 overflew the region around 1130 UTC while the eye was on land, and the toggle below shows Visible (0.64 µm) and Infrared Window Channel (10.8 µm) imagery from 1130 UTC. The cloud-filled eye is distinct in the infrared image at that time, but a sequence of POES AVHRR Infrared (12.0 µm) images showed the rapid deterioration shortly after landfall (as was seen in the GOES-13 images above).

A toggle between 1215 UTC GOES-13 Infrared Window (10.7 µm) and 1217 UTC DMSP-18 SSMIS Microwave (85 GHz) images from the CIMSS Tropical Cyclones site, below, revealed that a well-defined eye was still evident in the microwave data.

Aqua overflew Matthew shortly after 1800 UTC on 4 October, and the toggle below shows the 1-km visible (0.65 µm) and the 1-km ‘Cirrus Channel’ (1.38 µm). The Cirrus Channel detects radiation at a wavelength where very strong absorption by water vapor is occurring; only high clouds are detected with this channel, and the toggle between the Cirrus Channel and the Visible nicely outlines the cirrus canopy of the storm. The Advanced Baseline Imager (ABI) on GOES-R also includes a Cirrus Channel.

Meanwhile, to the northeast of Matthew, in the tropical Atlantic, Tropical Storm Nicole has formed. The animation of visible imagery from GOES-13, below, shows a sheared storm; the low-level circulation is west of the deepest convection. It’s unlikely that Nicole will intensify much under such sheared conditions. Cirrus outflow from Matthew is evident at the south and west of Nicole.

ASCAT on METOP-A sampled both storms in its morning overpass over the western Atlantic, as shown below. The maximum scatterometer-derived wind speeds were 60 knots with Matthew and 40 knots for Julia.

Late in the day on 04 October, Category 4 Hurricane Mathew made a second landfall along the far eastern tip of Cuba. As seen in the image toggle below, in spite of a ragged appearance on GOES-13  Infrared Window (10.7 µm) imagery, a distinct eye was still seen using DMSP-18 SSMIS Microwave (85 GHz) data.

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The Day/Night Band is a component of the VIIRS Instrument on board Suomi NPP, and it allows for satellite views in the visible portion of the electromagnetic spectrum at night. The nighttime light source is the Moon (if it is above the horizon), or airglow if not (or if the Moon is new). When Suomi NPP overflew Matthew early in the morning on 1 and 2 October, shortly after the New Moon (on 30 September), only airglow was illuminating the storm. Those images are shown above (for 1 October 2016) and below (for 2 October 2016). This imagery was produced using Polar2Grid software that is part of the CSPP Package using data received at a direct broadcast site (in this case, Miami).

There are striking mesospheric airglow gravity waves evident to the east and north of the center on 1 October, at which time Matthew was a Category 5 storm on the Saffir-Simpson scale, having undergone remarkable intensification during the previous 24 hours. On October 2, the gravity waves are not quite so apparent (at this time, the storm was a Category 4 storm). Are the gravity waves a response to the strong intensification?

Lightning streaks are present to the east of the center, within the cluster of deep convection east of Matthew, in both images. City lights on the islands of the Greater Antilles, and over the South American landmass, are also apparent. Haiti is notable for its minimal signature of city lights.

Matthew is forecast to affect Jamaica, eastern Cuba and Haiti on Monday and Tuesday, 3 and 4 October. Consult the website of the National Hurricane Center for more information.

Day/Night Band imagery will be available from JPSS-1, scheduled for launch no earlier than March 2017. After its launch, both Suomi NPP and JPSS-1 will provide Day/Night Band imagery. JPSS-2, -3 and -4 (scheduled for launch in 2021, 2026 and 2031, respectively), will also have a Day/Night Band capability. There are currently no plans for a geostationary Day/Night Band capability (In particular, GOES-R does not have a Day/Night Band).

======================== Added, 3 October =======================The Day/Night Band image from early on 3 October, below, also shows evidence of gravity waves that are perturbing the airglow, and of lightning in the convective complex well east of the center of Matthew.

Shown below is the same VIIRS Day/Night Band image, as viewed using AWIPS II with data received by the Puerto Rico ground station.

======================== Added, 4 October =======================The Day/Night Band early on 4 October continues to show gravity waves in the airglow. Note how city lights in Haiti are mostly absent in this image. This could be due to attenuation by the rain in the hurricane bands, or it could be due to infrastructure failure (or both).

======================== Added, 5 October =======================Here is the storm-centered Day/Night Band image for 5 October (also shown below). The ragged center of Matthew is barely visible over the water north of eastern Cuba. Haiti continues to show no man-made light sources. Parts of western Dominican Republic also show no lights. In both places, thick clouds and heavy rain may be the reason.

======================== Added, 5 October =======================The image from 6 October is here, with a different version shown below. The center of Matthew is apparent east of the island of Andros in the Bahamas. Note that city lights have returned to Port-au-Prince, Haiti (station MTPP), but they’ve vanished from several Bahama islands. In the zoomed-out version of the Day/Night Band that includes the United States, increased illumination is apparent over the western Gulf of Mexico. The Moon is starting to appear near the horizon during NPP’s overpass; increased illumination in these images should be the result in the next couple days.

At 0633 UTC on 7 October, Matthew was located east of the Atlantic coast of Florida. Lightning streaks are apparent well to the east of the center. This Day/Night Band image centered over Haiti shows that electricity has been restored to most of the island.

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