In-flight turbulence affected Hawaiian Air Flight 51 (JFK to HNL) late in the afternoon on 17 November 2021 (Click here for the flight path from the flightaware website. A screen-capture of the flight levels, below (cropped from the FlightAware website), shows turbulence occurring between 0141 and 0145 UTC on 18 November as the plane was flying at FL400 near 22.5º N, 154º W. That places the storm in the middle of MOG values exceeding 50% in a convective storm to the northeast of Hawaii, a storm in which other planes were also experiencing turbulence, as shown in the animation above (taken from the CIMSS Turbulence website). Here is the image for 0150 UTC, right after the turbulence affected the aircraft.

One passenger suffered a minor head injury during this event, and declined treatment. (Link). Training on this product is available at this site (direct link to recording is here).

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GOES-17 ABI Imagery (and level 2 Products), below, show persistent vigorous convection developing in a region with Lifted Indices around -2. Level 2 Cloud Top Height, at bottom, (the colorbar has been modified from default values to 35000-45000 feet), show persistent development of cloud tops exceeding 40000 feet, the cruising level of HAL51!

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GOES-17 (GOES-West) True Color RGB images created using Geo2Grid (above) showed a cyclonically-rotating actinoform cloud feature that was moving west-southwestward across the East Pacific Ocean (about midway between Hawai’i and California) on 16 November 2021.

In GOES-17 Day Cloud Phase Distinction RGB images (below), the increasing shades of green exhibited by the curved bands of shallow convection suggested that those features were likely mixed-phase clouds — composed of a combination of liquid/supercooled water droplets and ice particles. 

Similarly, in a toggle between NOAA-20 VIIRS True Color and False Color RGB images viewed using RealEarth (below), darker shades of cyan suggested the presence of mixed-phase banded cloud elements within the core of the actinoform feature.

Other examples of actinoform clouds can be examined by scrolling through this link.

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MIMIC Total Precipitable Water, shown above, shows a narrow ribbon of rich moisture stretching from north of Hawaii northeastward to the Pacific Northwest. Rainfall associated with this Atmospheric Rivr resulted in widespread flooding over Washington State (USA) and British Columbia (Canada). The system also generated very strong winds.

CMORPH estimates of rain, below, from Real Earth, show substantial 24-h rain amounts on 14-15 November, with peak values on 15 November of 75 mm in southern British Columbia. (This automated gauge along the Nooksack River at North Cedarville WA showed >4″ of rain (graph)) The 7-day accumulation ending at 2359 UTC on 15 November shows a few values in excess of 200 mm. CMORPH estimates suggest that heaviest rains were just north of the US-Canada border.

The excess rain’s impact on Nooksack Falls, north of Washington’s Mt Baker are shown below.

Satellite estimates of flooding are available at this website. For example, the image below (from this direct RealEarth link) shows flood extent over northwestern Washington (note the US-Canada border in the image) on 16 November 2021.

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News videos of the impact of the flooding on the Sumas Prairie near Abbottsford are here, here, here and here. Click here for video footage from near Sumas, WA. Other Washington imagery is here. This storm was well-forecast, as noted here.

Measured streamflow on the Nooksack River reached historic or near-historic volumes, as shown in these streamflow plots at North Cedarville (graph), Everson (graph) and Ferndale (graph) (all from this site).

NOAA-20 true-color imagery, below, from 31 October and 16 November, taken from the VIIRS Today website, show silt from this flood event.

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The difference between the 16 November and 17 November Joint ABI/VIIRS Flood Extent product is shown below. The extensive flooding on the Sumas Prairie near Abbotsford in Canada is apparent.

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The polar orbiting satellite Metop-A was switched off on 15 November 2021, ending a very long career gathering information (the satellite was launched in 2006). The final ASCAT (ascending) imagery from Metop-A, from this site, is shown above (click here to see the descending data from that day). ASCAT scatterometery from satellites operated by EUMETSAT will now be limited to Metop-B and Metop-C (Click here for more information on Metop-A in the near future; click here for information on Metop satellites). ASCAT data is obviously important for defining wind features over the open ocean, where conventional data is sparse.

The loss of Metop-A ASCAT data means a 50% reduction in the scatterometery data assimilated into US Numerical models. Only Metop-B ASCAT data are now assimilated; work continues on incorporating Metop-C ASCAT data into assimilation schemes.

Metop-A also carried AVHRR, IASI, HIRS, AMSU and MHS instruments. Metop-C is Metop-A’s replacement.

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*Metop-A does continue to supply some (non-ASCAT) information to NESDIS (my thanks to Liam Gumley, SSEC, for this information!) as shown at this website. Not all instruments have (as yet) been switched off.

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