Eruption of Manam in Papua New Guinea

October 19th, 2021 |

Himawari-8 True Color RGB images [click to play animated GIF | MP4]

The Manam volcano in Papua New Guinea erupted around 2200 UTC on 19 October 2021. JMA Himawari-8 True Color RGB images created using Geo2Grid (above) showed lower- to middle-altitude ash clouds (shades of tan to brown) moving westward and northward, while the main eruptive cloud — composed of a mixture of ash, SO2 and ice particles — spread out at high altitudes to the east and north. (Side note: brief flashes of sun glint off some of the island rivers were also seen.)  

Retrieved values of Ash Height from the NOAA/CIMSS Volcanic Cloud Monitoring site (below) indicated that the Manam eruption cloud reached maximum altitudes within the 16-18 km range. 

Himawari-8 Ash Height [click to play animated GIF | MP4]

GOES-17 Fog/Low Stratus (FLS) product availability in AWIPS

October 18th, 2021 |

GOES-17 MVFR Probability over the PACUS Sector [click to play animation]

The suite of Fog/Low Stratus (FLS) products derived using GOES-17 (GOES-West) data within the PACUS Sector (above) became available via the Satellite Broadcast Network (SBN) for AWIPS on 18 October 2021. Two examples are shown below: one centered over Oregon, and the other centered over the Big Island of Hawai’i. The 4 products are Marginal Visual Flight Rules (MVFR, cloud ceiling 1000 to 3000 feet above ground level and/or visibility 3 to 5 miles) Probability, Instrument Flight Rules (IFR, cloud ceiling 500 feet to less than 1000 feet and/or visibility 1 to less than 3 miles) Probability, Low Instrument Flight Rules (LIFR, cloud ceiling less than 500 feet and/or visibility less than 1 mile) Probability and Cloud Thickness. 

GOES-17 MVFR Probability (top left), IFR Probability (top right), Low IFR Probability (bottom left) and Low Cloud Thickness (bottom right) [click to play animation]

GOES-17 MVFR Probability (top left), IFR Probability (top right), Low IFR Probability (bottom left) and Low Cloud Thickness (bottom right) [click to play animation] 

GOES-17 FLS products are also being produced by CIMSS over the Alaska region (below) — which are being distributed via an LDM feed.

GOES-17 MVFR Probability (top left), IFR Probability (top right), Low IFR Probability (bottom left) and Low Cloud Thickness (bottom right) [click to play animation]

A library of FLS applications can be found on the GOES-R Fog Product Examples site, and FLS Forecaster Training is available here.

Alisal Fire in Southern California

October 12th, 2021 |

GOES-17 True Color RGB images [click to play animated GIF | MP4]

GOES-17 (GOES-West) True Color RGB images created using Geo2Grid (above) showed the transport of smoke from the Alisal Fire in Southern California on 12 October 2021. The dashed line in the images is Highway 101 — a portion of which was closed, as the wind-driven fire raced toward the coast. Late in the day some low-altitude smoke began to move eastward along the coast, eventually reducing the surface visibility to 6 miles at Santa Barbara.

During the preceding overnight hours (at 0916 UTC or 2:16 am PDT), a comparison of Suomi-NPP VIIRS Shortwave Infrared and Day/Night Band images (below) revealed the thermal signature and nighttime glow of the fire. The VIIRS imagery was downloaded and processed via the SSEC/CIMSS Direct Broadcast ground station.

Suomi-NPP VIIRS Shortwave Infrared (3.74 µm) and Day/Night Band (0.7 µm) images [click to enlarge]

The Suomi-NPP overpass time of the fire region was actually 0926 UTC — and a time-matched comparison of Shortwave Infrared images from GOES-17 and Suomi-NPP (below) demonstrated that the superior spatial resolution of VIIRS instrument (~375 meters, vs ~2 km for the ABI on GOES-17) provided a more accurate depiction of the areal coverage of the fire.

Shortwave Infrared images from Suomi-NPP (3.74 µm) and GOES-17 (3.9 µm) [click to enlarge]

===== 13 October Update =====

GOES-17 True Color RGB images [click to play animated GIF | MP4]

On 13 October, GOES-17 True Color RGB images (above) showed that as offshore wind speeds relaxed, a shift to onshore flow recirculated some of the smoke inland — with smoke briefly reducing the surface visibility to 1.5 miles at Santa Barbara airport (below). Farther to the south, residual smoke from the previous day of burning was also evident, with some of it traveling as far as Isla Guadalupe (Guadalupe Island) nearly 400 miles away.

Time series of surface observation data from Santa Barbara Municipal Airport [click to enlarge]

Severe thunderstorms in the Southern Plains

October 10th, 2021 |

GOES-16 “Red” Visible (0.64 µm) images, with SPC Storm Reports plotted in red [click to play animation | MP4]

1–minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) include time-matched plots of SPC Storm Reports produced by supercell thunderstorms that moved eastward across Oklahoma and Texas late in the day on 10 October 2021. These storms developed along and ahead of a strong cold front — and in Texas the hazy signature of post-frontal blowing dust was evident immediately behind the western edge of the convective cloud line.

GOES-16 “Clean” Infrared Window (10.35 µm) images (below) revealed pulsing overshooting tops that exhibited infrared brightness temperatures in the -70 to -75ºC range (shades of white embedded within dark black pixels).

GOES-16 “Clean” Infrared Window (10.35 µm) images, with SPC Storm Reports plotted in cyan [click to play animation | MP4]