Advanced Clear-Sky Processor for Ocean (ACSPO) temperatures over Lake Superior on 6 September, shown above, show a large area of surface temperature below 55^oF (magenta and white in the enhancement) over central Lake Superior. Clear early-Autumn skies allowed for this mostly complete view of the Lake Surface. Although Lake Superior was quite cold with respect to normal in late June (see this graph), its surface waters are now very close to normal. Note how much warmer the northern end of Lake Michigan is! The yellow enhancement shows temperatures close to 70^oF.

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The animation below shows VIIRS ACSPO temperatures off the coast of Oregon from 3 separate overpasses. The strong north winds observed at the buoys strengthen oceanic upwelling, leading to the very cold ocean surface temperatures (51^o – 52^oF) along the Oregon coast.

GOES-R Satellites have level-2 Sea Surface Temperature products as well (link) that something like the ACSPO algorithm — albeit at lower spatial resolution. The toggle below compares the two products. VIIRS better captures the cold ribbon of water right along the coast. The GOES-R algorithm cloud mask at the time below is perhaps too stringent.

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On 4 September, strong nighttime radiation cooling led to the Lake Superior water temperatures being several degrees F warmer than the surface air temperatures at nearby inland locations (overnight minimum temperatures included 33ºF in far northern Wisconsin and 34ºF in Upper Michigan; note that the color scale used in the tweet below differs from the one above):

A sure sign of Autumn: when the #NOAA20 and #SuomiNPP #VIIRS sea surface temperatures of Lake Superior are warmer than the surface air temperatures at nearby inland sites… https://t.co/KyRC5PmfzP #MNwx #WIwx #Mwx pic.twitter.com/5lNMHRzIIf

— Scott Bachmeier (@CIMSS_Satellite) September 4, 2022

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The recent 3-day weekend was a 3-night extravaganza for Aurora enthusiasts with an active Aurora Borealis lighting up the sky for 3 nights in a row.  The VIIRS (Visible Infrared Imaging Radiometer Suite) Day Night Band Sensor flying on the Suomi-NPP and NOAA-20 polar-orbiting satellites captured stunning snapshots of the celestial phenomena during each North America overpass.  

Auroras are visible signatures of disturbances in Earth’s magnetosphere that occur when the solar wind interacts with Earth’s magnetic field during geomagnetic storms and substorms. They typically flow between 100 to 500 km above Earth’s surface. Polar-orbiting satellites fly at an altitude of 824 km (512 miles) and are perfectly situated to observe and monitor the Aurora Borealis in the Northern Hemisphere or Aurora Australis in the Southern Hemisphere.

Uniquely sensitive to low levels of visible light at night, VIIRS Day Night Band is the only satellite sensor able to detect and display the Aurora. The DNB is sensitive to radiation in wavelengths between 0.5 – 0.9 µm, which covers much of the visible and some near-infrared wavelengths. The images appear monochromatic because they are a combination of all energy within the entire bandwidth, meaning we can’t separate out the “green” or “red” parts of the data to see vibrant colors that citizen science photographers capture from below. Thousands of Northern Lights pictures were shared on social media over the weekend. Here are just a few …

Day Night Band images from North America satellite overpasses are available via the VIIRS Imagery Viewer , a 7-day archive — refreshed daily — for all 22 VIIRS channels, usually within 60 minutes of being acquired onboard the spacecraft. Current and archived VIIRS images over the continental USA are also available on the VIIRS TODAY website. As future JPSS VIIRS satellites join the fleet, that data will also be available on these sites.

Of note: the JPSS-2 (NOAA-21) satellite is scheduled for launch on November 1st, 2022.

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Overlapping 1-minute Mesoscale Domain Sectors provided 30-second GOES-18 (GOES-West) Fire Temperature RGB images, along with GOES-17 Fire Detection and Characterization Algorithm (FDCA) products (above) — which showed thermal signatures of the larger Ross Fork Fire and the smaller Wildhorse Fire in southern Idaho on 04 September 2022. The Wildhorse Fire caused a closure of US Highway 20, just west of Hill City, for a period of 12 hours.

The #wildhorsefire has closed US- 20 near Pine Turnoff. The fire is currently about 20-25 miles west of #fairfield #Idaho #idwx pic.twitter.com/CIftSoHZdM

— NWS Boise (@NWSBoise) September 5, 2022

The Ross Fork Fire burned very hot, with Shortwave Infrared (3.9 µm) infrared brightness temperatures reaching 137.88ºC (the saturation temperature of GOES-18 ABI Band 7 detectors). For those hottest fire pixels, occasionally FDCA parameters (Fire Temperature, Fire Power, Fire Area and Fire Mask) were generated and displayable via AWIPS cursor sampling (below).

Note, however, that FDCA parameters were not displayable in AWIPS for Cloudy Fires (fires with partial obscuration by pyrocumulus clouds and/or optically-thick smoke) or for Saturated Fires (below). Part of this issue is related to the fact that the peak GOES-18 3.9 µm temperature (137.88ºC) was slightly lower than the peak 3.9 µm value for GOES-16/-17 (138.71ºC).

 

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GOES-18 (GOES-West) Day Land Cloud Fire RGB and Shortwave Infrared (3.9 µm) images along with GOES-17 Fire Power and Fire Temperature products (above) displayed characteristics associated with the Cedar Creek Fire in Oregon on 02 September 2022. The peak 3.9 µm infrared brightness temperature reached 137.88ºC, with Fire Power values exceeding 2000 MW and Fire Temperature values exceeding 1200 K. The Fire Power and Fire Temperature products are components of the Fire Detection and Characterization Algorithm (FDCA).

GOES-18 True Color RGB images created using CSPP GeoSphere (below) showed the large smoke plume produced by this wildfire, which spread north-northeastward across Washington State during the day.

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