DMSP « CIMSS Satellite Blog

Cyclone Fani makes landfall in India

May 3rd, 2019 | Scott Bachmeier

EUMETSAT-8 Meteosat-8 Infrared Window (10.8 µm) umages [click to play animation | MP4]

EUMETSAT Meteosat-8 Infrared Window (10.8 µm) images [click to play animation | MP4]

EUMETSAT Meteosat-8 Infrared Window (10.8 µm) images (above) showed the intensification of Cyclone Fani to a high-end Category 4 storm on 02 May 2019 (ADT | SATCON | PGTW advisory), before eventually making landfall in northeastern India at 0230 UTC on 03 May. During its life cycle, Fani moved over warm sea surface temperature values of 29-30ºC — and deep-layer wind shear of only 5-10 knots on 02 May provided an environment favorable for rapid intensification.

Once inland, Fani was in the process of rapidly weakening to a Category 1 storm as it passed over Bhabaneswar (VEBS), and surface wind gusts to 75 knots were reported at that site (below).

Time series plot of surface observations from Bhabaneswar, India [click to enlarge]

A sequence of VIIRS Infrared Window (11.45 µm) images from NOAA-20 and Suomi NPP as viewed using RealEarth (below) showed snapshots of Fani from 19 UTC on 01 May (over the Bay of Bengal) to 07 UTC on 03 May (after landfall).

Sequence of NOAA-20 and Suomi NPP VIIRS Infrared Window (11.45 µm) images [click to enlarge]

A comparison of VIIRS True Color Red-Green-Blue (RGB) and Infrared Window (11.45 µm) images from NOAA-20 and Suomi NPP on 02 May (below) showed Fani shortly after it had reached Category 4 intensity.

VIIRS True Color RGB and Infrared Window (11.45 µm) images from NOAA-20 and Suomi NPP [click to enlarge]

DMSP-17 SSMIS Microwave (85 GHz) image at 1230 UTC + Meteosat-8 Infrared Window (10.8 µm) image at 1300 UTC [click to enlarge]

A toggle between a DMSP-17 SSMIS Microwave image at 1230 UTC and a Meteosat-8 Infrared Window image at 1300 UTC from the CIMSS Tropical Cyclones site (above) showed the eye and totally closed eyewall of Fani when it was at its peak intensity on 02 May. However, the MIMIC TC product (below) indicated that the eastern portion of the eyewall started to erode as Fani approached the coast and began to undergo an eyewall replacement cycle.

MIMIC TC morphed microwave product, 01-02 May [click to enlarge]

On 30 April, VIIRS DayNight Band (0.7 µm) images (below, courtesy of William Straka, CIMSS) revealed widespread mesospheric airglow waves (reference) within the western semicircle of the storm, along with numerous bright lightning streaks associated with convection south of the storm center.

Suomi NPP VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images at 1939 UTC on 30 April [click to enlarge]

NOAA-20 VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images at 2029 UTC on 30 April [click to enlarge]

Posted in DMSP, Meteosat, Microwave, NOAA-20, RealEarth, Red-Green-Blue (RGB) images, Satellite winds, Suomi NPP, Tropical cyclones, VIIRS | No Comments »

Tropical Cyclone Veronica north of Australia

March 21st, 2019 | Scott Bachmeier

Suomi NPP VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images at 1716 UTC [click to enlarge]

A toggle between Suomi NPP VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images (above) showed Category 4 Cyclone Veronica off the northern coast of Western Australia at 1716 UTC on 21 March 2019. Ample illumination from a Full Moon maximized the “visible image at night” capability of the Day/Night Band.

In a comparison of Microwave images from Suomi NPP ATMS at 1716 UTC and from GCOM-W1 AMSR2 at 1732 UTC (below), an eyewall that was nearly completely closed was apparent. Suomi NPP and GCOM-W1 images courtesy of William Straka, CIMSS.

Microwave images from Suomi NPP ATMS at 1716 UTC and from GCOM-W1 AMSR2 at 1732 UTC [click to enlarge]

A DMSP-17 SSMIS Microwave (85 GHz) image at 2246 UTC from the CIMSS Tropical Cyclones site is shown below. The deep-layer Wind Shear at 21 UTC was low (green contours), and Sea Surface Temperature values were quite high — both factors favorable for continued intensification as Veronica moved slowly toward the coast.

DMSP-17 SSMIS Microwave (85 GHz) image at 2246 UTC, with an overlay of 21 UTC deep-layer Wind Shear, and Sea Surface Temperature [click to enlarge]

2.5-minute interval rapid scan Himawari-8 Infrared Window (10.4 µm) images (below) showed increasing organization to the eyewall structure. At times the cloud-top infrared brightness temperatures were -90ºC and colder (yellow pixels embedded within darker purple). Note: the rapid scan sector was re-poositioned eastward at 0100 UTC (to monitor Cyclone Trevor), so 10-minute imaging resumed after that time.

Himawari-8 Infrared Window (10.4 µm) images [click to play animation | MP4]

After sunrise, rapid scan Himawari-8 “Red” Visible (0.64 µm) images (below) revealed that the large eye was completely cloud-filled.

Himawari-8 “Red” Visible (0.64 µm) images [click to play animation | MP4]

Posted in DMSP, GCOM-W1, Himawari-8, Microwave, Satellite winds, Suomi NPP, Tropical cyclones, VIIRS | No Comments »

Cyclone Idai makes landfall in Mozambique

March 14th, 2019 | Scott Bachmeier

Meteosat-8 Infrared (10.8 µm) and DMSP-17 SSMIS Microwave (85 GHz) images of Cyclone Idai at 1630 UTC [click to enlarge]

Meteosat-8 Infrared Window (10.8 µm) and DMSP-17 SSMIS Microwave (85 GHz) images of Cyclone Idai at 1630 UTC [click to enlarge]

Cyclone Idai — which had been slowly intensifying over warm water within the Mozambique Channel since 09 March — made landfall as a Category 2 storm along the coast of Mozambique on 14 March 2019 (storm track). A toggle between Meteosat-8 Infrared Window (10.8 µm) and DMSP-17 SSMIS Microwave (85 GHz) images from the CIMSS Tropical Cyclones site (above) revealed a large and well-defined eye and eyewall structure at 1630 UTC. Idai had been rated at Category 3 intensity during 3 periods of time during its life cycle, most recently at 12 UTC on the day of landfall.

At 1911 UTC, Metop-A ASCAT winds in excess of 60 knots were sampled just west of the eyewall region (below).

Meteosat-8 Infrared Window (10.8 µm) image, with plots of Metop-A ASCAT winds at 1911 UTC [click to enlarge]

A comparison of VIIRS True Color Red-Green-Blue (RGB) and Infrared Window (11.45 µm) images from NOAA-20 and Suomi NPP, visualized using RealEarth, is shown below.

NOAA-20 and Suomi NPP VIIRS True Color RGB and Infrared Window (11.45 µm) images [click to enlarge]

Idai had been moving through an environment of very low deep-layer wind shear — a favorable factor for maintaining its intensity — as shown in an animation of Meteosat-8 Infrared Window (10.8 µm) images (below).

Meteosat-8 Infrared Window (10.8 µm) images with contours of satellite-derived Deep-Layer Wind Shear valid at 18 UTC [click to enlarge]

The MIMIC TC product (below) suggested that Idai might have been in the early stage of an eyewall replacement cycle (ERC) just prior to making landfall. This, after completing a separate ERC during the preceding 48 hours.

MIMIC TC morphed microwave imagery [click to enlarge]

MIMIC TC morphed microwave image product [click to enlarge]

The eye of Idal was becoming cloud-filled as it approached the Mozambique coast, as seen on EUMETSAT Meteosat-8 High Resolution Visible (0.8 µm) images (below).

Meteosat-8 High Resolution Visible (0.8 µm) images [click to play animation]

A time series of surface data from the port city of Beira FQBR (below) showed deteriorating conditions before observations ceased at 15 UTC.

Surface observation data from Beira, Mozambique [click to enlarge]

Incidentally, an overpass of the Landsat-8 satellite on 11 March provided a 30-meter resolution view of the eye (below), soon after Idai’s first period of rapid intensification to Category 3 strength (SATCON). Surface mesovortices were apparent within the eye.

Landsat-8 False Color image of the eye of Idai on 11 March [click to play a zooming animation]

Flooding from Idai led to hundreds of fatalities in Mozambique and Zimbabwe.

Flooded areas near Beira on 19 Mar 2019 computed from #Sentinel1 #MozambiqueFloods @CopernicusEMS @CopernicusEU pic.twitter.com/2OdE6Ixzig

— Simon Gascoin (@sgascoin) March 20, 2019

Posted in DMSP, Landsat, Meteosat, Microwave, NOAA-20, RealEarth, Red-Green-Blue (RGB) images, Suomi NPP, Tropical cyclones, VIIRS | No Comments »

Typhoon Wutip in the West Pacific Ocean

February 21st, 2019 | Scott Bachmeier

NOAA-20 VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images at 1502 UTC [click to enlarge]

VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images from NOAA-20 at 1502 UTC (above) and from Suomi NPP at 1552 UTC (below) showed Category 2 Typhoon Wutip in the West Pacific Ocean (southeast of Guam) on 21 February 2019. With Moon in the Waning Gibbous phase (at 95% of Full), ample illumination was provided to highlight the “visible image at night” capability of the Day/Night Band.

Notable features included deep convection near the storm’s center of circulation (with the presence of subtle cloud-top gravity waves), and transverse banding along the eastern periphery of the cold central dense overcast. Bright pixels seen in the Suomi NPP Day/Night Band image were the result of clouds being illuminated by lightning activity. VIIRS images courtesy of William Straka, CIMSS.

Suomi NPP VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images at 1552 UTC [click to enlarge]

===== 22 February Update =====

Himawari-8 Infrared Window (10.4 µm) images [click to play MP4 animation]

Typhoon Wutip intensified to a Category 3 storm on 22 February (ADT | SATCON) — rapid scan JMA Himawari-8 Infrared Window (10.4 µm) images at 2.5 minute intervals (above) revealed cloud-top infrared brightness temperatures of -90ºC and colder (yellow pixels surrounded by darker purple) shortly after 00 UTC. Multiple convective bursts developed around the center of circulation, and evidence of eye formation was seen for a short time beginning around 1137 UTC.

Himawari-8 “Red” Visible (0.64 µm) images of Wutip (below) showed that a distinct cloud-free eye did not form during that time period.

Himawari-8 “Red” Visible (0.64 µm) images [click to play MP4 animation]

A DMSP-17 SSMIS Microwave (85 GHz) image from the CIMSS Tropical Cyclones site (below) showed a nearly complete ring of strong convection around the eye region at 0916 UTC. A 24-hour animation of MIMIC-TC morphed microwave imagery is available here.

DMSP-17 SSMIS Microwave (85 GHz) image [click to enlarge]

Prior to becoming a typhoon, Wutip had been moving over water with warm Sea Surface Temperatures and high Ocean Heat Content values (below).

Sea Surface Temperature and Ocean Heat Content [click to enlarge]

===== 23 February Update =====

Himawari-8 Infrared Window (10.4 µm) images [click to play MP4 animation]

2.5-minute rapid scan Himawari-8 Infrared Window (10.4 µm) images (above) revealed the formation of a large and well-define eye with an annular eyewall structure as Wutip rapidly intensified (ADT | SATCON) to Category 4 Super Typhoon status on 23 February. Mesovortices could be seen rotating within the eye. Wutip became the most intense February typhoon on record in the Northwest Pacific basin.

In a toggle between NOAA-20 VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images at 1602 UTC (below), these mesovortices were also apparent — with the help of reflected moonlight — in the Day/Night Band.

NOAA-20 VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images at 1604 UTC [click to enlarge]

As noted in a 21 UTC discussion from the JTWC, Wutip had a well-defined poleward outflow channel within the upper troposphere (below), which was a favorable factor for its intensification.