Two more SAR data collections occurred over American Samoa waters on 16 February, as shown above. (This is part of an ongoing special collection that extends through early March). As with most previous observations, winds around American Samoa were light. Consider these ASCAT observations from MetopC at ca. 2040 UTC on 16 February 2023, for example, taken from this site. Observed winds are uniformly around 10 knots.

The most notable feature in the 0550 UTC winds above is the arc of showers to the northeast of American Samoa, shown below. Imagery from this time is also available at this website, both wind fields and Normalized Radar Cross Section (NRCS) fields. NRCS data suggests that the peak winds — those values exceeding 20 knots — might be where SAR energy is reflecting off ice in clouds, leading to a SAR-derived wind that is too strong.

How long do the winds in the SAR field above persist? The mp4 animation below (click here for an animated gif) from 0000 UTC to 2000 UTC tracks the cloud feature associated with the SAR observations at 0548 UTC to the east, but that feature is very difficult to discern in the second SAR overpass at 1650 UTC.

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US Space Force EWS-G1 — formerly GOES-13 — Infrared Window (10.7 µm) images (above) showed Cyclone Freddy in the South Indian Ocean, after it re-intensified to a Category 4 storm at 0000 UTC on 15 February 2023. Freddy then briefly peaked at 145 knots at 0000 UTC on 16 February (SATCON), making it the first Category 5 tropical cyclone of 2023.

Meteosat-9 Infrared Window (10.8 µm) images from the CIMSS Tropical Cyclones site (below) included contours and streamlines of deep-layer (850-200 hPa) wind shear. The intensification of Freddy occurred in spite of this environment of moderate east-southeasterly shear.

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Two SAR satellite (RADARSAT-2 and RCM-1) overpasses occurred at 0000 UTC on 16 February, as noted here.

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True Color RGB images — created using Geo2Grid — from GOES-18 (GOES-West), GOES-17 and GOES-16 (GOES-East) (above) displayed dense plumes of blowing dust across parts of New Mexico, Texas and Oklahoma on 14 February 2023. Strong winds (with gusts in the 60-85 mph range) in the wake of a cold front lofted dry topsoil from areas that were experiencing Moderate to Exceptional Drought conditions.

GOES-17 (formerly GOES-West) was temporarily operating from its pre-storage checkout position over the Equator at 104.7 W longitude.

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True- and False-color imagery of Lake Erie from VIIRS data on NOAA-20, above, show a Lake largely clear of ice in mid-February (!). Cyan colors in the False-color imagery do suggest lake ice along the northern shore of Erie, however, to the east of Kingsville Ontario, and to the east of Port Stanley Ontario. The regions with ice are circled in this annotated false color image.

Clear skies meant that the Advanced Clear-Sky Processing for Ocean (ACSPO) algorithm could produce estimates of lake surface temperatures, shown below. The warmest temperatures — near 37^oF, green in the enhancement — are just northeast of Erie, PA.

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In fact, most of the Great Lakes had clear skies at 1836 UTC. Click here to see the SSTs. The mostly clear skies continued overnight on 14 February, and the image below shows ACSPO SSTs and the Day Night Band.

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