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Lake Effect Season begins

CSPP Geosphere imagery, above (link), shows a band of cumulus clouds over central Lake Michigan. The still image, below, from 1600 UTC shows cool air and surface winds converging into this band. The toggle from 1201 UTC, below, shows the band in the Night Microphysics RGB with NEXRAD reflectivity overlain,... Read More

GOES-16 Visible (band 2, 0.64 µm) imagery, 1251 – 1511 UTC on 14 October 2024

CSPP Geosphere imagery, above (link), shows a band of cumulus clouds over central Lake Michigan. The still image, below, from 1600 UTC shows cool air and surface winds converging into this band.

GOES-16 Visible Imagery (Band 2, 0.64 µm), and Level 2 Lake Surface Temperatures (all values exceed 15 C) (Click to enlarge)

The toggle from 1201 UTC, below, shows the band in the Night Microphysics RGB with NEXRAD reflectivity overlain, and also surface and 850-mb observations. Note the 850-mb temperatures at Green Bay (-2o C) and at Detroit (-1o C) and at Gaylord MI (-5o C).

GOES-16 Night Microphysics along with NEXRAD Reflectivity, Surface Observations and 850-mb RAOB plots (Click to enlarge)

The temperatures at 850-mb are below zero (Celsius) and Lake Surface Temperatures are in the 17-18oC range (below, source). That difference is greater than the ca. 13 Celsius degrees needed to support Lake Effect bands.

Diagnosed Lake Surface Temperatures, 1200 UTC on 14 October 2024 (Click to enlarge)

The Lake Effect season has begun!

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Airmass RGB imagery and MIRS snowfall rates over northern Alaska

Parts of northern Alaska were under a Winter Storm Warning for much of the weekend, as shown below by the red regions to the north of Fairbanks. (The red regions around the Seward Peninsula were regions where a High Wind Warning had been cancelled after strong winds weakened. This toggle of MetopB and MetopC ASCAT winds from 0530-0630 UTC on 13 October (source)... Read More

GOES-18 AIrmass RGB imagery, 2000 UTC 12 October – 2350 UTC 13 October 2024 (Click to enlarge)

Parts of northern Alaska were under a Winter Storm Warning for much of the weekend, as shown below by the red regions to the north of Fairbanks. (The red regions around the Seward Peninsula were regions where a High Wind Warning had been cancelled after strong winds weakened. This toggle of MetopB and MetopC ASCAT winds from 0530-0630 UTC on 13 October (source) shows the very strong winds offshore). The Airmass RGB animation (created using Geo2Grid software) above shows the abundant mid-level moisture streaming north and the development of a storm system by 1200 UTC on 13 October as evidence by the comma cloud.

Screen Capture of hazards from WFO Fairbanks, ca. 1500 UTC on 13 October 2024 (click to enlarge)

What products can be used to highlight where snow might be falling over northern Alaska, where no radars are present, and where webcams are scarce. Microwave Integrated Retrieval System products include snowfall rate. This product is computed from Microwave sounders on board many Low-Earth-Orbit (LEO) satellites including Suomi-NPP, NOAA-20/NOAA-21, and MetopB/C. The animation below shows values (computed from data downloaded at the GINA Direct Broadcast antenna and processed using CSPP software; created imagery is here). The heaviest snowfall is diagnosed to the south of the Brooks Range through about 1400 UTC (as shown in this image from 0452 UTC, for example), at which point maximum snowfall shifts to the north.

MiRS Snow Fall Rate, 0343-2344 UTC on 13 October 2024 (Click to enlarge)

Polar2Grid software can be used to create MIRS snowfall rate imagery with data downloaded from (for example) Amazon Webservice websites that hold Suomi NPP or NOAA-20 data. The toggles below compare the computed Snowfall rates and the airmass RGBs. As is often the case over Alaska, the GOES animations give the evolution of the atmosphere and LEO data gives important smaller-scale information, in this case snowfall rates. The heaviest snow is diagnosed to occur right in the comma head over the near the Brooks Range from 1130-1331 UTC. By 2300 UTC, the heaviest snowfall rates have diminished. MiRS snowfall rates are available in Alaska Region AWIPS machines for a simple comparison to other satellite imagery.

GOES-18 airmass RGB at 1130 UTC on 13 October and Suomi-NPP Snowfall rate at 1127 UTC on 13 October 2024 (Click to enlarge)
GOES-18 airmass RGB at 1150 UTC on 13 October and NOAA-20 Snowfall rate at 1150 UTC on 13 October 2024 (Click to enlarge)
GOES-18 airmass RGB at 1330 UTC on 13 October and NOAA-20 Snowfall rate at 1331 UTC on 13 October 2024 (Click to enlarge)
GOES-18 airmass RGB at 2300 UTC on 13 October and Suomi-NPP Snowfall rate at 2303 UTC on 13 October 2024 (Click to enlarge)

Microwave Snow Fall Rate imagery is also available at this website. The Snow Fall Rate Quick Guide is here.

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Aurora on 11 October

Another vivid auroral display occurred over the northern United States and southern Canada early on 11 October (and was also visible late on the 10th!). Day Night Band imagery from JPSS Satellites, above, show the patterns in the emitted energy.RealEarth includes Day Night Band imagery, as at this link. ... Read More

VIIRS Day Night Band visible (0.7 µm) imagery from 0548-0820 UTC on 11 October 2024

Another vivid auroral display occurred over the northern United States and southern Canada early on 11 October (and was also visible late on the 10th!). Day Night Band imagery from JPSS Satellites, above, show the patterns in the emitted energy.

RealEarth includes Day Night Band imagery, as at this link.

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Stereoscopic 30-second views of Milton from 9 October, Bands 2 and 5

Both mesosectors for GOES-16 and GOES-19 were placed over Hurricane Milton on 9 October. Consequently, 30-second imagery from both satellites was acquired. The animation above shows visible imagery from sunrise to 2159 UTC. To view a three-dimensional image, cross your eyes so that three images are present, and focus on... Read More

GOES-16 (left) and GOES-19 (right, preliminary, non-operational data) Visible imagery (Band 2, 0.64 µm) from 1100 – 2159 UTC on 9 October 2024

Both mesosectors for GOES-16 and GOES-19 were placed over Hurricane Milton on 9 October. Consequently, 30-second imagery from both satellites was acquired. The animation above shows visible imagery from sunrise to 2159 UTC. To view a three-dimensional image, cross your eyes so that three images are present, and focus on the image in the middle. A similar animation showing the ‘snow-ice band‘, GOES-R Band 5 at 1.61 µm, is below.

GOES-16 (left) and GOES-19 (right, preliminary, non-operational data) near-infrared imagery (Band 5, 1.61 µm) from 1100 – 2159 UTC on 9 October 2024

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