===== 01 June Update =====The remnant circulation of Bonnie moved very slowly northeastward during the 30 May – 01 June period, as seen in GOES-13 Visible (0.63 µm) images covering each of those 3 days (above; also available as a large 95 Mbyte animated GIF). The periodic formation of deep convective clusters continued to produce heavy rainfall over parts of far eastern North and South Carolina.
On the morning of 01 June, an overpass of the Metop-B ASCAT instrument sampled the flow around the low-level circulation center (LLCC) off the coast of North Carolina; several hours later, Suomi NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images provided a high-resolution view of the system at 1755 UTC (below). Cloud-top IR brightness temperatures were as cold as -78º C within the small convective cluster located just north of the LLCC.
As Roanu was moving along the east coast, very hot surface air temperatures were seen in the western portion of India on 19 May, with many sites reporting temperatures in excess of 110ºF. The animation below shows hourly Infrared images with surface METAR reports, as viewed using RealEarth.INSAT 3D Visible (0.65 µm) images with hourly surface temperatures in ºF (above) revealed temperatures as warm as 122ºF at Ahmadabad, at 10 UTC and 12 UTC; a plot of the time series of weather condition at Ahmadabad is shown below. Farther to the north at the city of Phalodi (whose location is denoted by the gray * symbol) a temperature of 123.8ºF or 51.0ºC was recorded, which set an all-time record for the highest temperature officially measured in India (the previous record was 50.6ºC, set in 1886 at Pachpadra)..
EUMETSAT Meteosat-7 Infrared Window (11.5 µm) images (below) showed the formation of a well-defined eye after about 03 UTC.A comparison of Meteosat-7 Infrared (11.5 µm) and DMSP-18 SSMI Microwave (85 GHz) images from the CIMSS Tropical Cyclones site (below) showed the eye structure around 15 UTC.
===== 18 April Update =====During the 17-18 April period Cyclone Fantala reached Category 5 intensity (ADT plot), with maximum sustained winds of 150 knots (making it the strongest tropical cyclone on record in the South Indian Ocean); Fantala also became the longest-lived hurricane-strength tropical cyclone on record for that ocean basin. Meteosat-7 Infrared Window (11.5 µm) images (above) showed the storm reaching peak intensity as it moved just north of the island of Madagascar.
A comparison of Suomi NPP VIIRS Infrared Window (11.45 µm) and Day/Night Band (0.7 µm) images (below) offered a detailed nighttime view of the eye of Fantala at 2249 UTC on 17 April. Side lighting from the Moon (in the Waxing Gibbous phase, at 81% of full) helped to cast a distinct shadow within the eye, and also provided a good demonstration of the “visible image at night” capability of the Day/Night Band.