GOES-16 (GOES-East) “Red” Visible (0.64 µm), Shortwave Infrared (3.9 µm) and “Clean” Infrared Window (10.35 µm) images (above) showed a series of pyrocumulonimbus (pyroCb) pulses emanating from the Mullen Fire in southeastern Wyoming on 19 September 2020. Each of the  pulses exhibited 10.35 µm brightness temperatures of -40ºC and colder  (shades of blue) — assuring the heterogeneous nucleation of all supercooled water droplets to form ice crystals, thereby meeting the criteria of a pyroCb.

The coldest cloud-top infrared brightness temperatures were around -47ºC, which corresponded to altitudes near 11 km according to rawinsonde data from Riverton, Wyoming (below).

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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 — with and without an overlay of GLM Flash Extent Density (above) showed Hurricane Teddy as it rapidly intensified (ADT | SATCON ) to a Category 4 storm on 17 September 2020. The coldest cloud-top infrared brightness temperatures were in the -80 to -85ºC range.

Metep-A ASCAT surface scatterometer wind speeds were as high as 74 knots in the northwestern portion  of the eyewall (below).

Microwave (85 GHz) DMSP-17 (at 1023 UTC), GMI (at 1720 UTC) and DMSP-18 (at 2034 UTC) images from the CIMSS Tropical Cyclones site are shown below.

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A Medicane (a portmanteau of Mediterranean and Hurricane) has developed in the central Mediterranean Sea, and moved northeastward through the Ionian Sea towards Greece and Albania. Daily snapshots of VIIRS true-color imagery, above, from NASA Worldview, show a slow increase in organization. (Previous CIMSS Blog Posts on Medicanes are here, here and here.) This Medicane was given the name ‘Ianos’.

There is an isolated region of small values of wind shear over this system (1800 UTC image from 17 September, from this website), as expected for a tropical storm.  An image of hourly CMORPH precipitation values, below, show heavy precipitation associated with the storm as well.

The ASCAT instrument on Metop-B observed a very tight cyclonic circulation on 16 September, as shown below (imagery from this site).

MIMIC Total Precipitable Water (TPW) (below, from this site) shows a compact swirl around the storm, with large values of TPW.

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NASA’s IMERG product showed the heavy rain that was associated with this storm as it moved towards Greece.

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Hurricane Sally weakened to a Tropical Storm at 1800 UTC on 16 September. Sally is a prodigious rainfall producer. CMORPH (CPC Morphing Technique) Precipitation estimates (blogged about earlier) are available at this Real Earth website. Hourly estimates from 1300 through 2200 UTC are shown above.  Many locations over southern Mississippi show hourly multi-inch accumulations for much of the day.

Daily precipitation for the 24 hours ending at 00 UTC on 17 September is shown below.  A large area of Mississippi shows values between exceeding 100-150 mm.  Click here to see a 24-h precipitation total image for the period ending 1200 UTC on 17 September (from this website) A series of daily images of 24-hour precipitation (at bottom) shows the evolution of the diagnosed precipitation from 09-16 September.

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