1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images — with and without an overlay of GLM Flash Extent Density (above) showed Marco as it intensified from a Tropical Storm to a Category 1 hurricane at 1630 UTC on 23 August 2020. A pronounced semi-circular convective burst was seen to develop near the storm center shortly before 19 UTC.

A toggle between time-matched Infrared images from Suomi NPP and GOES-16 (below) indicated that the coldest cloud-top infrared brightness temperature on the Suomi NP VIIRS image was -86.8ºC, compared to -81.5ºC from the GOES-16 ABI instrument (the same color enhancement has been applied to both images). The northward parallax displacement associated with GOES-16 imagery over the southern Gulf of Mexico was also apparent.

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Tropical Storm Marco over the northwest Caribbean Sea, shown above in a toggle of GOES-16 ABI Clean window imagery (10.3 µm) and a NUCAPS diagnosis of 850-500mb lapse rates, is over very warm waters and in a region of favorably low diagnosed vertical wind shear. (Wind shear is from this website, (direct link to shear); the product is described here)  An inhibiting feature in strengthening, as noted in the National Hurricane Center discussion, is stable air.

NOAA-20 overflew Marco shortly before 0700 UTC on 22 August, and NUCAPS soundings derived from CrIS and ATMS data on NOAA-20 showed the stable mid-tropospheric air surrounding the storm. The 850-500 mb lapse rates were around 5.5 C/km. (Gridded NUCAPS data can also be viewed here) Individual soundings over western Cuba and just off the northwest tip of the Yucatan peninsula also show the relatively stable air. (Click here to see the Lapse Rate Analysis overlain with NUCAPS Sounding Availability points from the AWIPS display)

Marco’s future path is forecast to move over very warm waters that are shown in the ACSPO analysis of SSTs, below, from Suomi-NPP VIIRS data.  Consult the National Hurricane Center for the latest on this storm that will likely affect the Texas/Louisiana Gulf Coasts.

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A comparison of Suomi NPP VIIRS Day/Night Band (0.7 µm) and Near-Infrared (1.61 µm and 2.25 µm) images along with the VIIRS Active Fires product (above) showed nighttime visible reflectance and thermal signatures of the numerous wildfires that were burning across Northern California at 1001 UTC or 3:01am PDT on 20 August 2020. A closer view is available here.

1-minute Mesoscale Domain Sector GOES-17 (GOES-West) Fire Temperature Red-Green-Blue (RGB) and “Red” Visible (0.64 µm) images (below) displayed the thermal signatures and smoke plumes associated with the Northern California fires.

GOES-17 True Color RGB images created using Geo2Grid (below) provided a closer view of the dense residual smoke and new smoke plumes across Northern California.

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 1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images (above) displayed the well-defined eye of Category 4 Hurricane Genevieve in the East Pacific Ocean (off the west coast of Mexico) on 18 August 2020. Genevieve underwent a period of rapid intensification during the pre-dawn hours that day (ADT plot).

A GOES-16 Visible image at 1617 UTC (below) includes plots of Metop-A ASCAT scatterometer surface winds — the highest wind was 69 knots just northeast of the storm center.

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