Tropical cyclones « CIMSS Satellite Blog

Hurricane Dora

June 26th, 2017 | Scott Bachmeier

GOES-16 Visible (0.64 µm) and Infrared Window (10.3 µm) images [click to play MP4 animation]

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

Dora became the first hurricane of the Eastern Pacific 2017 season on 26 June, and was also the first hurricane to be sampled by GOES-16. On Visible (0.64 µm) and Infrared Window (10.3 µm) images (above), Dora displayed an improving appearance as the day progressed — mesovortices were seen within the eye on Visible imagery, while the overall eye/eyewall structure improved as the eye diameter increased on Infrared Window imagery.

Early in the morning, a comparison between DMSP-17 SSMIS Microwave (85 GHz) and GOES-15 Infrared Window (10.7 µm) images from the CIMSS Tropical Cyclones site (below) showed that a well-defined eye was more apparent on microwave imagery. Dora was moving over fairly warm Sea Surface Temperatures, and was also in an environment characterized by low values of deep-layer wind shear.

DMSP-17 SSMIS Microwave (85 GHz) and GOES-15 Infrared Window (10.7 µm) images [click to enlarge]

Posted in DMSP, GOES-15, GOES-16, Satellite winds, Tropical cyclones | No Comments »

Tropical Storm Cindy

June 24th, 2017 | Scott Bachmeier

GOES-16 Visible (0.64 µm, left) and Infrared Window (10.3 µm, right) images, with hourly surface//ship/buoy reports plotted in yellow [click to play MP4 animation]

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

As Tropical Storm Bret was forming off the coast of South America, Potential Tropical Cyclone 3 (PTC3) was becoming more organized as it moved from the western Caribbean Sea across the Yucatan Peninsula of Mexico and into the Gulf of Mexico on 19 June 2017 (MIMIC TPW). On 20 June, one of the GOES-16 Mesoscale Sectors was positioned over PTC3 and provided 1-minute imagery — Visible (0.64 µm) and Infrared Window (10.3 µm) images (above) showed deep convective bursts moving northward to reveal an exposed Low Level Circulation Center (LLCC).

GOES-16 Visible (0.64 µm, left) and Infrared Window (10.3 µm, right) images, with hourly surface/buoy/ship reports plotted in yellow [click to play MP4 animation]

Early in the day on 21 June, 1-minute GOES-16 Visible and Infrared Window images (above) showed multiple LLCC features associated with PTC3, with deep convection remaining well to the north/northwest. In addition, Mid-level Water Vapor (6.9 µm) images (below) indicated that a large amount of dry air had wrapped into the southern and eastern portions of the storm circulation.

GOES-16 Visible (0.64 µm, left) and Water Vapor (6..9 µm, right) images [click to play MP4 animation]

However, by mid-day a more consolidated central circulation had developed, as seen on Suomi NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images (below) — and PTC3 was upgraded to Tropical Storm Cindy.

Suomi NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images, with surface pressure plotted in yellow and station identifiers plotted in cyan [click to enlarge]

Hourly images of the MIMIC Total Precipitable Water product covering the 19-24 June period (below) showed the northward transport of rich tropical moisture into the Gulf Coast states, which then moved northeastward toward the Northeast US bringing heavy rainfall and flooding to many locations (WPC storm summary).

MIMIC Total Precipitable Water [click to play animation]

Maps of daily rainfall during the 21-24 June period (along with 7-day rainfall totals, departure from normal and percent of normal) are shown below.

21-24 June daily precipitation, along with 7-day Precipitation Total, 7-day Departure from Normal and 7-day Percent of Normal [click to enlarge]

Posted in GOES-16, Heavy rain / flooding, Suomi NPP, Tropical cyclones, VIIRS | No Comments »

Tropical Storm Bret

June 19th, 2017 | Scott Lindstrom

GOES-16 “Veggie” Band (0.86 µm) animation of Tropical Storm Bret, 1545-2030 UTC on 19 June 2017 (Click to animate)

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

The fast-moving tropical system in the southern Caribbean Sea has developed a closed circulation and has been named Bret. Tropical Storm Bret, shown above in an animation of GOES-16 Near-Infrared (0.86 µm) imagery that highlights land/water contrasts (the Orinoco River in Venezuela and Caribbean Islands — some with cloud streamers in their lee — north of Venezuela stand out clearly), is forecast to remain very close to the South American coastline. Such proximity to land will likely hinder development. Further, wind shear in the atmosphere over the storm is predicted to increase.

Bret is embedded within a ribbon of very moist air (associated with the ITCZ) that stretches from Africa to the northwest Caribbean, as shown in the animation below (taken from this site) that shows morphed microwave observations of total precipitable water.

Microwave estimates of Total Precipitable Water for the 24 hours ending 1900 UTC on 19 June 2017 (Click to enlarge)

For more information on Bret, refer to the National Hurricane Center and the CIMSS Tropical Cyclones sites (where you can also follow the future of the system emerging into the Gulf of Mexico).

Posted in GOES-16, Metop, POES, Satellite winds, Suomi NPP, Tropical cyclones | No Comments »

Tropical Storm Adrian

May 10th, 2017 | Scott Bachmeier

GOES-16 Infrared Window (10.3 µm) images [click to play animation]

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

East Pacific Ocean Tropical Depression 1E intensified to become Tropical Storm Adrian (at 9.5º N latitude, 92.3º W longitude) at 03 UTC on 10 May 2017 — making it the earliest tropical storm on record in the East Pacific basin during the meteorological satellite era. GOES-16 Infrared Window (10.3 µm) images (above) revealed a series of nocturnal convective bursts which exhibited cloud-top infrared brightness temperatures in the -80º to -89º C range (shades of violet color enhancement).

During the subsequent daylight hours, GOES-16 Visible (0.64 µm) images (below) showed that southeasterly deep layer wind shear (source) had decoupled the organized convection from the exposed low-level circulation center (LLCC). Due to the far southern location of Adrian, only Full Disk scan images were available, at 15-minute intervals.

GOES-16 Visible (0.64 µm) images [click to play animation]

However, one of the GOES-16 Mesoscale Sectors was positioned over Adrian during the 2226-2355 UTC period, providing images of the LLCC at 1-minute intervals (below).