Suomi NPP Day Night Band Visible (0.7 µm) Imagery, ~0600 UTC, 21 September 2017 (Click to enlarge)

Suomi NPP Overflew Puerto Rico at ~0555 UTC on 21 September, and the Day Night Band Visible Imagery (0.7 µm), above (from Real Earth, direct link here), shows city lights from San Juan and Ponce on the northeast and southwest shores, respectively, shining through relatively thick clouds to the southeast of the eye of the storm.

Annotated Imagery from Suomi NPP (VIIRS Day Night Band Visible (0.7 µm) Imagery and Infrared (11.45 µm) courtesy of William Straka) are shown below.

Suomi NPP Day Night Band Visible (0.7 µm) Imagery, 0554 UTC on 21 September 2017 (Click to enlarge)

Suomi NPP VIIRS Infrared (11.45 µm) Imagery, 0554 UTC on 21 September 2017 (Click to enlarge)

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GOES-16 Derived Convective Available Potential Energy (CAPE), 1702-2137 UTC on 20 September 2017 (Click to enlarge)

GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing

GOES-16 Data are used to create many Baseline Products that can be used to monitor and anticipate weather.  The animation above shows the GOES-16 Convective Available Potential Energy (CAPE).  Values increased by about 50-75% in a corridor from southern Wisconsin southwestward to Missouri over the course of four hours as shown in the loop.  CAPE varies over Illinois, with a minimum extending from Chicago southwestward, with larger values to the east and to the west.  The CAPE developed in a region where the Storm Prediction Center had a slight risk of severe weather. A Mesoscale Discussion for the region was also issued. Hail up to two inches in diameter was reported in central Wisconsin.

Baseline Stability Products are Clear-Sky only products. (They are also available online here, albeit delayed.) Because they are Clear-Sky products, they are most useful for monitoring the pre-convective environment.

GOES-16 Visible (0.64 µm) Imagery, 1702-2137 UTC on 20 September 2017 (Click to enlarge)

Visible Imagery (0.64 µm) for the same period as the CAPE animation, above, shows the development of convection along a front moving into Wisconsin. Note also the lack of cumulus development in the CAPE minimum over Illinois.  The large CAPE values over southwestern Missouri were not tapped, as convection did not trigger there.

(Added: Click here to see a Band 13 “Clean Window” Infrared (10.3 µm) animation from GOES-16, from 2302 UTC on 20 September to 0652 UTC on 21 September.)

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GOES-16 Visible Imagery (0.64 µm), 1017-1117 UTC, at 30-second time steps, on 20 September 2017 (Click to animate)

GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing.

Strong Category 4 Hurricane Maria has made landfall in Puerto Rico. According to the National Hurricane Center, landfall occurred around 1035 UTC near Yabacuo on Puerto Rico’s southeast coast. The GOES-16 30-second (using overlapping mesoscale sectors) Visible Animation, above, shows the storm as it made landfall. Maria had recently completed an Eyewall Replacement Cycle as it made landfall. The animation below, using morphed microwave imagery (from this site), shows the development of an outer eyewall and subsequent erosion of the inner eyewall during the 24 hours prior to landfall.

Morphed Microwave Imagery centered on Hurricane Maria for the 24 hours prior to landfall in Puerto Rico (Click to enlarge)

GOES-16 Clean Window Infrared (10.3 µm) Imagery shows a distinct eye as the storm makes landfall. Subsequently, however, the eye filled in as it moved over the mountainous interior of Puerto Rico.

GOES-16 Infrared (10.3 µm) Imagery, 0957-1136 UTC on 20 September 2017 (Click to animate)

GOES-16 Visible (0.64 µm, left) and Infrared Window (10.3 µm, right) images (Click to play MP4 animation)

A 2-panel comparison of GOES-16 Visible (0.64 µm) and Infrared Window (10.3 µm) imagery during the 1020-1620 UTC time period is shown above. It can be seen that deep eyewall convection moved over much of the island as Maria made its journey across Puerto Rico.

Suomi NPP flew over Maria early in the morning on 20 September, when the storm was near St. Croix. The toggle below shows the 11.45 µm Infrared image from VIIRS and the Day Night Band Visible (0.7 µm) Imagery. The Moon on 20 September was a New Moon, so no lunar illumination was present for the Day Night Band. The eye of the storm was nevertheless apparent in the image.  A zoomed-in Infrared image over the eye is here.

Suomi NPP VIIRS 11.45 µm Infrared image from VIIRS and the Day Night Band Visible (0.7 µm) Imager, 0613 UTC on 20 September 2017 (Click to enlarge)

Suomi NPP overflew Maria again when the storm was moving offshore from Puerto Rico, and a toggle (Visible and Infrared) below shows the storm at 1724 UTC on 20 September. Click here for a zoomed-in image (Visible) over the eye.

Suomi NPP VIIRS 11.45 µm Infrared image from VIIRS and Visible (0.64 µm) Image, 1724 UTC on 20 September 2017 (Click to enlarge)

More information on Maria is available at the National Hurricane Center and at the CIMSS Tropical Weather Website.

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GOES-16 “Clean Window” Infrared 10.3 µm imagery, 0055 to 0414 UTC on 19 September 2017 (Click to play 161 M animated gif)

GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing

GOES-16 ABI 10.3 µm Infrared Imagery shows the path of Category 5 Hurricane Maria’s transit across the Caribbean Island of Dominica. The compact eye moved from east-central Dominica to the northwest coast of Dominica over the course of about 2 hours late on the 18th and early on the 19th of September 2017.

===================== Added, 2130 UTC on 19 September 2017 =====================

Later in the day on 19 September, Suomi NPP overflew Category 5 Hurricane Maria. The toggle below shows the Visible (0.64 µm) and Infrared Window (11.45 µm) imagery zoomed in over the eye. A Caribbean Basin-wide view (visible and infrared toggle) is below that. The storm displays excellent structure with strong banding and outflow and little indication of shear.  (Suomi NPP Imagery courtesy William Straka, CIMSS)

Suomi NPP Visible (0.64 µm) and Infrared (11.45 µm) imagery over the eye of Hurricane Maria, 1742 UTC on 19 September 2017 (Click to enlarge)

Suomi NPP Visible (0.64 µm) and Infrared (11.45 µm) imagery of Hurricane Maria over the eastern Caribbean, 1742 UTC on 19 September 2017 (Click to enlarge)

For more on the Hurricane Maria, consult the webpages of the National Hurricane Center or the CIMSS Tropical Weather Website.

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