A series of Advanced Scatterometer (ASCAT) images (ascending passes) from Metop-B, above, show a large region of gale force winds surrounding the Hawai’ian Islands between 3 April and 5 April 2024. The entire island chain is under Wind Advisories or Gale Warnings; additionally, High Surf Advisories are in effect on the eastern sides of most islands as shown in the screen capture of the website of the Honolulu NWS Forecast Office below. Small Craft Advisories are also widespread around the islands.

The strong winds are Equatorward of an unusually strong Anticyclone (> 1050 mb!) that has been moving through the north-central Pacific Ocean as depicted in the GFS model output shown below (taken from this website).

Synthetic Aperture Radar (SAR) winds (source), below, also show gale-force winds in/around Hawai’ian islands, but the islands are blocking winds such that relatively calm regions extend for some distance downwind of the islands. (The lighter winds in the lee of the islands show up in the scatterometry fields shown above as well, most especially in the imagery from 4 April).

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What do the waves look like? Altimetry data, below, shows slowly building Significant Wave Heights (defined as the average of the highest 1/3rd of the wave heights) between 3 and 5 April 2024. (Imagery from here)

Observed waves (from this website) north of Maui, below, and east of Kaneohe Bay, Oahu (bottom) also show building wave heights from 3-5 April.

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5-minute CONUS Sector GOES-16 (GOES-East) True Color RGB images from the CSPP GeoSphere site (above) displayed smoke plumes from widespread prescribed burning in the Flint Hills of eastern Kansas and Oklahoma on 04 April 2024. There were also dense smoke plumes originating from another cluster of prescribed burns in the vicinity of the Oklahoma/Arkansas border.

GOES-16 “Red” Visible (0.64 µm) images with an overlay of the Fire Mask derived product (a component of the GOES Fire Detection and Characterization Algorithm FDCA) depicted the areal coverage and diurnal behavior of the fire thermal signatures (below). A similar animation using the GOES-16 Fire Power derived product is available here: GIF | MP4.

Judging from the surface reports, most of the smoke appeared to have been dispersed above the boundary layer (a few locations intermittently reported the base of the smoke layer to be in the 2200-4400 ft range) — but the surface visibility was briefly reduced by smoke to 4-6 miles at sites such as Emporia, Kansas and Claremore, Oklahoma (below).

Previous examples of the annual Flint Hills prescribed burn activity during the Spring season have been documented on this blog in 2022, 2019, 2017,and 2010.

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Metop-C and NOAA-20 are now both supplying NUCAPS profiles to National Weather Service AWIPS machines. Both the vertical profiles and gridded fields are available. The toggle above shows all the MetopC overpasses early on 4 April, and it includes horizontal maps of 850-mb Temperatures derived from the Metop-C NUCAPS profiles. Large swaths of satellite-derived fields are available at times (0220 UTC, 0356 UTC) when radiosondes typically are not being launched. These fields are ideal to compare to model fields as a method of model evaluation.

The toggle below compares the three overpasses of MetopC Sounding Availability points to one overpass from NOAA-20. The two satellites have very different orbital paths. NOAA-20 overlaps different MetopC orbits; the time difference if you’re comparing data varies depending on where you are in the NOAA-20 orbit.

What kind of gridded fields were available on this day? The toggle below compares the 850-mb Temperature fields from Metop-C (0220 UTC) and NOAA-20 (0832 UTC). Over the western Great Lakes and parts of Canada, this is giving information on how the 850-mb fields are evolving during those 6 hours between radiosonde releases.

You can also derive a notion on how temperatures are changing over the southern part of the NOAA-20 pass, but that requires using a later MetopC pass, as shown below in the toggle that compares 850-mb temperatures from Metop-C NUCAPS (0356 UTC) and the NOAA-20 field at 0832 UTC.

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This is a lot of excellent data that can be used, day or night. Starting in May, data from NOAA-21 will be added as well! If you’re using AWIPS, the most efficient way to view these fields is by creating Procedures.

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While the view of the Sun from the ground may, or may not be, affected by clouds during the eclipse on April 8th, the view of the Moon’s shadow on the Earth will be viewed from NOAA‘s GOES ABI. There will be imagery every 10 min from the Full Disk sectors, and 5 min from the Contiguous U.S. (CONUS) sector. There will be two Mesoscale sectors from GOES-16 ABI, although it’s not yet certain where they will be located on the Earth that day. Most likely “M1” will “follow” the shadow, while “M2” will move around to monitor any possible severe weather. There are many sites with imagery from the Mesoscale sectors, including NOAA/NESDIS/STAR (M1) and UW/SSEC geosphere (M1) and CIRA’s slider (M1).

Research Request

There has been a research request to have the Mesoscale sectors generally ‘follow’ the shadow. The idea is that the center point of the sector would change every 5 min. This would be similar to the Mesoscale scan strategy used during August 2017 eclipse (see this animation from UW/CIMSS), where the centers changed every 10 min. The second meso (M2) will be moved to monitor possible severe weather. More on the recent/planned meso locations. Of course any operational request will preempt this research request.

These ‘simulated’ mesos (M1) are cookie-cut from the Full Disk sector. It’s possible that M1 center will be updated every 5 minutes. There is a google form for researchers to request special sectors (for events such as rocket launches, etc.). The request link is also on this page of many GOES related links.

H/T

Thanks to those investigating if these meso’s can be generated on April 8th, including the NOAA NESDIS User Services team. Fun fact, this research request was initially submitted on May 3, 2023. Thanks also for the Eclipse Predictions by Fred Espenak, NASA’s GSFC. McIDAS-X was used for image generation. Thanks to the satellite operators, SDM, PRO, SAB and the NWS.

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