Pyrocumulonimbus cloud in Canada’s Northwest Territories

June 24th, 2022 |

GOES-18 “Red” Visible (0.64 µm, top), Shortwave Infrared (3.9 µm, center) and “Clean” Infrared Window (10.35 µm, bottom) images, which include hourly plots of surface reports [click to play animated GIF | MP4]

GOES-18  images in this blog post are preliminary and non-operational

GOES-18 “Red” Visible (0.64 µm), Shortwave Infrared (3.9 µm) and “Clean” Infrared Window (10.35 µm) images (above) showed the formation of a small pyrocumulonimbus (pyroCb) cloud — generated by a wildfire that was burning near the northwest coast of Great Slave Lake in the Northwest Territories of Canada — on 24 June 2022. The pyroCB cloud then drifted southeastward across the lake, toward Resolute Bay (CYFR). Incidentally, this was Canada’s first documented pyroCb of the 2022 wildfire season.

Suomi-NPP VIIRS Visible (0.64 µm), Shortwave Infrared (3.74 µm) and Infrared Window (11.45 µm) images valid at 1930 UTC, with plots of surface reports [click to enlarge]

Suomi-NPP VIIRS Visible (0.64 µm), Shortwave Infrared (3.74 µm) and Infrared Window (11.45 µm) images valid at 1930 UTC (above) showed the pyroCb shortly after it formed (when it exhibited a minimum cloud-top 11.45 µm infrared brightness temperature of -49C, lighter shades of red) — and Suomi-NPP VIIRS images valid at 1930 UTC (below) displayed the pyroCb over Great Slave Lake at 2110 UTC (when it exhibited a minimum cloud-top 11.45 µm infrared brightness temperature of -54C, darker shades of violet).

Suomi-NPP VIIRS Visible (0.64 µm), Shortwave Infrared (3.74 µm) and Infrared Window (11.45 µm) images valid at 2110 UTC, with plots of surface reports [click to enlarge

30-second GOES-17 images over Utah and Colorado

June 23rd, 2022 |

GOES-17 “Red” Visible (0.64 µm) images, with plots of hourly surface reports [click to play animated GIF | MP4]

The radar at NWS Grand Junction, Colorado (KGJT) was down for scheduled maintenance in late June 2022 — and on 23 June, overlapping 1-minute Mesoscale Domain Sectors provided 30-second GOES-17 (GOES-West) “Red” Visible (0.64 µm) images (above), which showed the development of thunderstorms across a portion of their County Warning Area (which includes eastern Utah and western Colorado) to help fill their gap in radar coverage. These particular storms did not reach severe levels, but some produced small hail, strong winds and heavy rainfall (Local Storm Reports).

Alaskan wildfire smoke

June 22nd, 2022 |

GOES-18 True Color RGB images [click to play animated GIF | MP4]

GOES-18 images in this blog post are preliminary and non-operational

GOES-18 True Color RGB images created using Geo2Grid (above) showed smoke from Alaskan wildfires that had been transported southward over Kodiak Island and the northern Gulf of Alaska. Most of this smoke remained aloft — note that although Kodiak began reporting smoke late in the day, the surface visibility remained at 10 miles (below).

Plot of surface report data from Kodiak, Alaska [click to enlarge]

A composite of VIIRS True Color imagery (below) showed the location of active fires over Alaska on that day.

Composite of VIIRS True Color imagery, with fire thermal signatures shown in red [click to enlarge]

Hail damage swaths in Nebraska and Iowa

June 20th, 2022 |

GOES-16 Normalized Difference Vegetation Index and Day Land Cloud Fire RGB images, with and without Cities labels [click to play animated GIF | MP4]

GOES-16 (GOES-East) Normalized Difference Vegetation Index (NDVI) and Day Land Cloud Fire RGB images (above) revealed several hail damage swaths — which appeared as brighter shades of yellow in the NDVI images, and shades of brown in the RGB images — across parts of Nebraska and Iowa on 20 June 2022. The swaths of cropland damage were the result of wind-driven hail events that occurred on 06 June, 07 June and 14 June. One of the swaths was nearly 90 miles long (due to a series of training thunderstorms), with some swaths as wide as 10 miles in places.