NOAA’s Hazardous Weather Testbed is an annual evaluation (by National Weather Service forecasters) of experimental satellite-based products that provide useful information during convective weather events. One of the demonstration products this year is a model with initial conditions that have assimilated fused polar hyperspectral soundings from NOAA-20/NOAA-21 and MetOp satellites. The animations above and below compare the simulated Composite Reflectivity (at hourly intervals from the 1500 UTC model run) with observed LightningCast probabilities (used here as a proxy for convection). In both cases, the Composite Reflectivity grossly captures the evolution and development of convection.

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The image above shows a 7-h forecast of Composite Reflectivity over North Dakota, valid at 2300 UTC on 8 June 2023 (Note: your blogger mistakenly saved this one instead of the 6-h forecast at 2200 UTC, but the two were similar). Convection is predicted for an east-west line across the southern part of the state, with convective complexes stretching north and east of the western terminus of the line. Additional convection appears in western Montana, and over northern South Dakota. How does that compare to the observations shown below? The east-west line of observed convection is a bit farther south than predicted. The convective complexes stretching northeastward from the western terminus of that east-west line are a bit farther east than predicted. There is less convection in South Dakota than predicted. (The convection in Montana is not displayed in this particular radar sector, but it’s inferred by the satellite imagery! Overall, the predicted and observed convection match to some extent.

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The slider below compares a 6-h forecast valid at 1100 UTC on 9 June with the infrared imagery. The PHS model accurately captured the development of the southward-propagating Mesoscale Convective System over southeast South Dakota.

PHSnMWnABI model output are available at this link.

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GOES-18 (GOES-West) SO2 RGB, Shortwave Infrared (3.9 µm) and Fire Power derived product images (above) showed the SO₂ plume and thermal signature of an eruption of Kilauea that began at 4:44 AM HST or 1444 UTC on 07 June 2023. As of 1451 UTC (only 7 minutes after the onset of the eruption), the 3.9 µm infrared brightness temperature reached 137.88ºC — which is the saturation temperature of the GOES-18 ABI and 7 detectors — and Fire Power values peaked around 2100 MW (cursor sample). The Fire Power derived product is a component of the GOES Fire Detection and Characterization Algorithm (FDCA).

The thermal signature was also evident in Nighttime Microphysics RGB imagery from the CSPP GeoSphere site — and after sunrise the hazy SO₂-rich volcanic plume could be seen in True Color RGB images, drifting southwestward away from Kilauea and the Big Island of Hawai`i.

GOES-18 Ash RGB images created using Geo2Grid (below) showed the SO₂-rich volcanic cloud (shades of cyan) as it drifted southwest. According to the Hawaiian Volcano Observatory, a sulfur dioxide (SO₂) emission rate of approximately 65,000 tonnes per day was measured between approximately 8 and 9 a.m. local time (1800-1900 UTC).

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A recent blog post detailed a heavy rain event over the Kona section of Hawai’i, and the rain occurred several hours after NOAA-20 overpasses that included an unfortunately-placed data gap that included the Big Island of Hawai’i. Thick clouds over the region meant geostationary satellites could not provide information about the thermodynamics surrounding Hawai’i. The image below shows the early morning NOAA-20 orbits on this day. The pass just after 1100 UTC was far to the east of Hawai’i, and the pass before 1300 UTC was too far to the west to give good coverage over Hawai’i. The toggle above shows MIRS (that is, from microwave data) TPW values from NOAA-20 at the two times, downloaded from the NODD (NOAA-20 MIRS data are here; Suomi NPP are here) and processed with Polar2Grid to create imagery. Data over Kona is from the limb view and as such will have very poor resolution. However, of note (considering the development of convection over Kona between 1500 and 1600 UTC) is the maximum in TPW — orange values in the enhancement — west of Hawai’i and south of Oahu. How might that have evolved with time?

Suomi NPP and NOAA-20 orbits are such that they are half an orbit apart, so on this date Suomi NPP overflew Kona at 1150 UTC, giving a high resolution microwave view of Kona at a time in between the two NOAA-20 overpasses.

The single image TPW field from Suomi NPP, below, from 1152 UTC, shows some interesting features that might have influenced the line of convection that developed over Kona (the western portion of the big Island of Hawai’i). Note in particular the higher TPW values with a maximum extending south of the Big Island (highlighted by the arrow below), and a general maximum in TPW exists from that line westward to the maximum that is south of Oahu and west of Hawai’i (circled in the toggle below).

The three individual scenes of microwave-derived TPW are shown below. The multiple views at 1152 (Suomi NPP) and 1249 UTC (NOAA-20), in particular, allow a user to view moisture moving towards the Big Island of Hawai’i.

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The Canadian wildfire season has been off to an early start since the beginning of May, impacting air quality in parts of the United States since mid-May. Now, smoke from Quebec fires is back and affecting areas of the U.S. again, transporting as far south as Tennessee and Missouri. Air quality alerts have been issued across the Great Lakes area, including most of Wisconsin northern New York, as well as parts of Minnesota and Illinois.

The Canadian Wildland Fire Information System provides maps of recent fire data, including active fires and affected area estimates.

The CSPP Geosphere site offers quick and accessible true-color images of the wildfire smoke.

You can also combine fire scenes and true-color imagery using RealEarth, which allows you to display more than one data product simultaneously. RealEarth also archives a few days of data (depending on the product), so users can create animations over more than one day.

The 2023 fire season has only just begun in North America, and dry conditions are the primary reason for these early season Canadian wildfires.

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