Hurricane Chris accelerates away from the United States

July 11th, 2018 |

GOES-16 ABI Band 2 (“Red Visible”) Visible (0.64 µm) Imagery, 1852-2117 UTC on 11 July 2018 (Click to animate)

Hurricane Chris is accelerating away from the United States (although it will likely pass very close to Cape Race, Newfoundland Canada). Visible Imagery (GOES-16 ABI Band 2, “Red Visible”, at 0.64 µm), above, from late afternoon on 11 July shows a well-developed storm with a pronounced eye.

Before Sunrise on 11 July 2018, both NOAA-20 and JAXA’s Global Change Observation Mission (GCOM) Satellite overflew the storm at slightly different times.  The VIIRS (Visible Infrared Imaging Radiometer Suite) instrument NOAA-20 samples in the visible and infrared part of the electromagnetic spectrum whereas the AMSR2 Instrument (Advanced Microwave Scanning Radiometer 2) on GCOM samples in the microwave.  Because microwave energy can penetrate clouds, it can be used to estimate rainfall, and the toggle below steps through the Infrared (11.45 µm) and Day Night Band Visible (0.70 µm) from VIIRS (at 0645 UTC) as well as the Convective Precipitation and Surface Rain rate from AMSR2 (at 0618 UTC). 

Lunar illumination is absent  in the Day Night band visible imagery, but Earth glow nevertheless illuminates the eye of the storm;  in addition, two lightning streaks are visible north and east of the center.  Surface Rain and Convective Rain rates show the heaviest rains near the storm center, as expected (NOAA-20 VIIRS and GCOM AMSR2 imagery courtesy William Straka, CIMSS).

VIIRS Infrared (11.45 µm) and Visible (0.70 µm) Day Night Band Visible Imagery, 0645 UTC on 11 July 2018, and GCOM AMSR2 Convective Precipitation and Surface Rain Rate estimates at 0618 UTC on 11 July (Click to enlarge)

Hurricane Chris

July 10th, 2018 |

GOES-16

GOES-16 “Red” Visible (0.64 µm, left) and “Clean” Infrared Window (10.3 µm, right) images [click to play MP4 animation]

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.3 µm) images (above) showed Chris as it rapidly intensified (ADT | SATCON) to a Category 1 Hurricane by 2100 UTC (NHC discussion) on 10 July 2018.

A toggle between 375-meter resolution NOAA-20 Visible (0.64 µm) and Infrared Window (11.45 µm) images (below) revealed cloud-top infrared brightness temperatures as cold as -81ºC (violet enhancement) in a convective burst just northeast of the eye. [Note: the 1821 UTC NOAA-20 images are incorrectly labeled as Suomi NPP images]

NOAA-20 VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images [click to enlarge]

NOAA-20 VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images [click to enlarge]

Earlier in the day, a GPM satellite GMI Microwave (85 GHz) image from the CIMSS Tropical Cyclones site (below) showed that Tropical Storm Chris had not yet formed a closed eye at 1326 UTC.

GPM GMI Microwave (85 GHz) image [click to enlarge]

GPM GMI Microwave (85 GHz) image [click to enlarge]

However, a MIMIC-TC animation spanning the 0000 to 1925 UTC time period (below) showed the eye formation process completing as the estimated maximum speed (Vmax) increased from 60 to 75 knots.

MIMIC-TC morphed microwave image product [click to enlarge]

MIMIC-TC morphed microwave image product [click to enlarge]

Tropical Storm Chris

July 8th, 2018 |

GOES-16 Visible Imagery (Band 2, 0.64 µm), from 1837 – 2332 UTC on 8 July 2018 (Click to animate)

Tropical Depression Number 3 was upgraded to Tropical Storm Chris at 0900 UTC 8 July. Chris has been mostly stationary on 8 July. The visible animation, above, from Sunday 8 July shows excellent upper-level outflow to the northeast and southwest of the storm, and persistent convection over the center.  The Clean Window animation over the same time, below, shows a compact center with periodic overshooting tops.

GOES-16 Clean Window Infrared Imagery (Band 13, 10.3 µm), from 1837 – 2332 UTC on 8 July 2018 (Click to animate)

The toggle below between 2212 UTC on 6 and 8 July shows the general increase in organization of Chris, with a slight northwestward motion over the two days. In addition, the front that was over the eastern United States on 6 July is out over the Atlantic on 8 July, and Chris is embedded within the southwestern tail of the front.

GOES-16 Visible Imagery (Band 2, 0.64 µm), at 2212 UTC on 6 July and 8 July 2018 (Click to enlarge)

Tropical Depression #3 forms off the East Coast of the United States

July 6th, 2018 |

GOES-16 Visible Imagery (Band 2, 0.64 µm), from 1712 – 2212 UTC on 6 July 2018 (Click to animate)

Tropical Depression Three has formed in the Atlantic Ocean southeast of Cape Hatteras. The visible animation above (click the image to play an animated gif) shows strong convection with overshooting tops mostly south and west of a low-level circulation. The cold front over the eastern United States, and an upper-level Low that is moving inland over Florida, are also apparent. Because the depression is within GOES-16’s CONUS Domain, 5-minute imagery is available to monitor this system.

A variety of GOES-16 images and products can be used to discern whether this storm will develop (The National Hurricane Center suggests slow motion and slow development: Click here for details).

The low-level Water Vapor field, below (7.34 µm) from 2122 UTC, shows little dry air in the path of the storm. The Total Precipitable Water derived from GOES-16 ABI data similarly shows rich moisture surrounding the storm.

GOES-16 Low-Level Water Vapor (Band 10, 7.34 µm), 2212 UTC on 6 July 2018 (Click to enlarge)

GOES-16 Clean Window Infrared (Band 13, 10.3 µm) imagery superimposed upon GOES-16 Estimates of Total Precipitable Water, 2212 UTC on 6 July 2018 (Click to enlarge)

GOES-16 Estimates of Sea Surface Temperature, below, color-enhanced such that waters warmer than 27 º C are violet, shows warm surface waters. Gulf Stream temperatures, northwest of the Depression, are at 30-31 º C.

GOES-16 Estimates of Sea Surface Temperature, 2100 UTC on 6 July 2018 (Click to enlarge)

For more information on this system, please see the website of the National Hurricane Center and the CIMSS Tropical Weather Website.