Super Typhoon Yutu makes landfall on Tinian and Saipan

October 24th, 2018 |

Himawari-8 “Clean Window” Infrared (10.41 µm) Imagery, 0900-1540 UTC on 24 October 2018 (Click to animate)

Himawari-8 Clean Window Infrared (10.41 µm) imagery shows Super Typhoon Yutu poised to hit Tinian and Saipan in the Marianas Islands, to the northeast of Guam. The 0900 UTC Advisory from the Joint Typhoon Warning Center shows a storm with sustained winds of 145 knots, with strengthening forecast. JMA estimates a surface pressure of 905 hPa! (Link)

(Himawari data courtesy JMA and the NWS Pacific Region)

Update: Landfall on Tinian and Saipan occurred just before 1500 UTC; a closer view using 2.5 minute rapid scan Himawari-8 imagery can be seen here (station plot PGSN is Saipan, where reliable observations ceased after 1452 UTC).

Added: From William Straka, CIMSS. NOAA-20 had a fortuitous overpass, almost directly over Tinian at landfall. The Day Night Band Visible (0.7 µm) Imagery (with a full moon) and 11.45 µm infrared imagery is shown below).

NOAA-20 VIIRS Day Night Band visible (0.7 µm) imagery and I05 infrared (11.45 µm) imagery, 1551 UTC on 24 October 2018 (Click to enlarge)

CIMSS helps manage a Direct Broadcast (DB) antenna at the National Weather Service on Guam, and that antenna received both NOAA-20 and GCOM data as the eye was over, or close to, Tinian.  Microwave imagery from The Advanced Microwave Scanning Radiometer 2 (AMSR-2) on JAXA’s GCOM satellite, below, (courtesy Kathy Strabala, CIMSS) at 36.5 GHz and 89.0 GHz, reveals cloud and rainband structures that infrared imagery cannot.  In particular, the 89.0 GHz imagery suggests the formation of an outer eyewall ouside the very compact inner eye.  This typically is the start of an eyewall replacement cycle.

GCOM AMSR-2 imagery at 36.5 and 89.0 GHz, 1601 UTC on 24 October 2018 (Click to enlarge)

The DB antenna also processed data from NOAA-20, the same overpass as shown above, zoomed in over Tinian. The antenna is able to capture data over much of the western Pacific Basin, as the Day Night Band visible image shows below. A true color image from the previous overpass on Guam, 12 hours earlier, during daytime (0311 UTC on 24 October), is here.

NOAA-20 VIIRS Day Night Band visible (0.7 µm) imagery, 1544 UTC on 24 October 2018 (Click to enlarge)

Power Outages in the wake of Hurricane Michael

October 12th, 2018 |

VIIRS Day Night Band Visible (0.70 µm) Imagery from NOAA-20 on 6 October and 12 October 2018 (Click to enlarge)

The VIIRS (Visible-Infrared Imaging Radiometer Suite) instrument onboard NOAA-20 includes a Day Night Band that can be used to assess, among other things, power outages after a strong storm such as Hurricane Michael. The toggle above shows Day Night Band imagery from 6 October (before Michael) and 12 October (after Michael), and the change in illumination from city lights over the Florida Panhandle northeastward into east-central Georgia is stark.

Of course, clouds can also mask city lights in the Day Night Band. However, 11.45 µm infrared imagery from VIIRS, below, on 12 October, shows scant evidence of clouds over the region where city lights are missing.

VIIRS Infrared (11.45 µm) Imagery from NOAA-20, 12 October 2018, 0844 UTC (Click to enlarge)

(NOAA-20 images here courtesy William Straka, CIMSS)

Stereoscopic views of Hurricane Michael

October 8th, 2018 |

GOES-16 (left) and GOES-17 (right) visible (0.64 µm) imagery of Michael starting at 1147 UTC on 8 October 2018 (Click to play mp4 animation)

GOES-17 data in this post are preliminary and non-operational

CONUS (Contiguous United States) imagery at 5-minute intervals from GOES-16 at 75.2 W Longitude and GOES-17 at 89.5 W Longitude allows for Hurricane Michael to be viewed stereroscopically from space. The animation above, starting at 1142 UTC and extending to sunset, (click here for an animated gif) shows an intensifying Michael with strong convection developing over the center.  To view in three dimensions, cross you eyes until 3 images are present, and focus on the image in the center.  Very strong shear is also apparent northeast of Michael.  Low-level winds and upper-level winds do not align, and convection there is strongly tilted.  (This graphic of shear is from the CIMSS Tropical Weather Website)

Sea-surface Temperatures over the Gulf (Source), below, show abundant warm water between Michael and its project landfall location along the northeast Gulf Coast (See the National Hurricane Center for latest information).

Blended SST over the Gulf of Mexico, 7 OCtober 2018 (Click to enlarge)

The animation shows the stereoscopic view on 9 October 2018. An animated gif is available here.

GOES-16 (left) and GOES-17 (right) visible (0.64 µm) imagery of Michael starting at 1147 UTC on 9 October 2018 (Click to play mp4 animation)

The animation below is shows Michael’s eye at full GOES-16/GOES-17 resolution starting at 1402 UTC on 9 October.

GOES-16 (left) and GOES-17 (right) full-resolution visible (0.64 µm) imagery of Michael’s on 9 October 2018 (Click to play animated gif)

A full-resolution of Michael’s well-developed eye on 10 October is shown below.

GOES-16 (left) and GOES-17 (right) visible (0.64 µm) imagery of Michael starting at 1147 UTC on 10 October 2018 (Click to play animated gif)

Mode 4 Testing for both GOES-16 and GOES-17

October 1st, 2018 |

GOES-17 upper-level water vapor infrared imagery (6.19 µm) from 1425-1550 UTC on 1 October (Click to animate)

GOES-17 Data shown in this post are preliminary and non-operational.

Continuous Full Disk (Mode 4) Testing is occurring on October 1 2018.   Mode 4 is the highest data flow rate for the ABI and results in a Full Disk image every 5 minutes.  No mesoscale sectors are produced during Mode 4 operations.  Five-minute CONUS imagery can be produced by subsecting the 5-minute Full-Disk Imagery.  This testing started at 0000 UTC on 1 October and will end at 0000 UTC on 2 October.

The animation above shows GOES-17 Full-Disk imagery for the upper-level water vapor imagery (6.19 µm) with a 5-minute cadence.  The GOES-16 animation for the same time and location is below.

GOES-16 upper-level water vapor infrared imagery (6.19 µm) from 1425-1550 UTC on 1 October (Click to animate)

Careful inspection of the imagery from the two satellites might reveal differences in brightness temperatures between the two instruments. This difference is due to view-angle differences. When the satellite is scanning near the limb, computed brightness temperatures will be cooler because more information detected by the satellite comes from the upper part of the atmosphere. Compare, for example, brightness temperatures just west of former Pacific Hurricane Rosa just west of Baja California. GOES-17, at 89.5 W Longitude, sees warmer temperatures than GOES-16 at 75.2 W Longitude. GOES-16’s view is more oblique, and is through more of the colder upper atmosphere.

GOES-16 and GOES-17 upper-level water vapor infrared (6.19 µm) imagery at 1500 UTC on 1 October 2018 (Click to enlarge)

(Update: GOES-16 returned to Mode-3 scanning at 1549 UTC on 1 October. Continuous Full Disk scanning on GOES-16 lead to degradation of derived products).

Update #2: Animations of 5-minute Full Disk GOES-17 Mid-level Water Vapor (6.9 µm) and “Red” Visible (0.64 µm) images from 0000-2355 UTC on 01 October are shown below.

GOES-17 Mid-level Water Vapor (6.9 µm) images [click to play MP4 animation]

GOES-17 Mid-level Water Vapor (6.9 µm) images [click to play MP4 animation]

GOES-17

GOES-17 “Red” Visible (0.64 µm) images [click to play MP4 animation]

One interesting feature on GOES-17 Visible imagery was the east-to-west progression of sun glint off the water of the Amazon River and its tributaries, beginning near the mouth of the river in northeastern Brazil and ending in Ecuador (below).

GOES-17 "Red" Visible (0.64 µm) images [click to play MP4 animation]

GOES-17 “Red” Visible (0.64 µm) images [click to play MP4 animation]