The tropical disturbance (formerly 95W) in the western Pacific south of Guam (discussed here) has strengthened and become the second western Pacific named storm of the year: Malakas. The storm is about halfway between the islands of Guam and New Guinea. The side-by-side imagery above, showing Himawari Band 3 and Band 8 imagery (courtesy JMA), shows deep convection near the center of the storm that was at fairly low latitudes: around 6^o N at 0600 UTC on 8 April, the times of the imagery above. In addition, the storm is far from dry air. A 24-hour animation of the Band 3 (0.64 µm)/Band 13 (10.41 µm) sandwich product on 7 April 2022 below, taken from this site (see this blog post), shows the rotation of the system and the abundance of convection at the center.

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The forecast at 1200 UTC on 8 April from the Joint Typhoon Warning Center take this strengthening storm northwest, between Guam and Yap.

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Imagery from the SSEC/CIMSS Tropical Weather website, below, shows the storm in a region of low shear. An excellent ASCAT overpass at 1126 UTC on 8 April 2022 showed a closed-off center.

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Instrument Flight Rules (IFR) are rules and guidelines put in place by the Federal Aviation Administration that govern conditions in which “flight by outside visual reference is not safe”, whether by low clouds or fog. Cloud and reflectance data from geostationary satellites GOES-16 and GOES-17 provide a satellite IFR Probability product, by detecting fog and low stratus. More information on this product can be found here.

An example of GOES-17 IFR Probability is shown below in Southern California on April 7, 2022 at 1546UTC, displaying GOES-17 IFR Probability, IFR advisories issued by the Aviation Weather Center, and GOES-17 red band reflectance.

The full domain of GOES-17 IFR Probability may be useful for ocean prediction. GOES-16/17 IFR products are available on RealEarth.

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1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images along with 5-minute Fire Power and Fire Temperature products (above) displayed the smoke plume and thermal signature of a grassland fire that rapidly intensified and spread across parts of western Beaver County (located in the Oklahoma Panhandle) on 05 April 2022. The Fire Temperature and Fire Power derived products are components of the GOES Fire Detection and Characterization Algorithm FDCA. Thermal signatures became evident around 1700 UTC or Noon CDT; within about 2 hours this fire was already burning very hot, with 3.9 µm Shortwave Infrared brightness temperatures reaching 138.71ºC — the saturation temperature of ABI Band 7 detectors — around 1915 UTC.

A strong cold front was moving southward across the High Plains during the day (surface analyses) — and arrived at the grass fire’s location just after 2000 UTC (causing a brief flare-up of the fire thermal signatures, and a final pyrocumulus pulse). The surge of colder air behind the cold front showed up as darker shades of green in the 3.9 µm images. Th initial east-southeastward expansion of the hot thermal 3.9 µm signature quickly transitioned to a south-southwestward expansion in the wake of the frontal passage.

1-minute GOES-16 True Color RGB images created using Geo2Grid (below) showed the initial eastward spread of the smoke plume prior to the arrival of the cold front — followed by a pronounced south-southwestward transport of smoke from the fire source region after the cold front moved across the area.

The polar-orbiting Suomi-NPP satellite passed over that region around 1923 UTC — a toggle between True Color and False Color RGB images is shown below. The data to produce these images were downloaded and processed by the SSEC/CIMSS Direct Broadcast ground station (and are available for display in AWIPS via an LDM feed).

Incidentally, Beaver County in Oklahoma experienced another fast-moving grass fire in March 2020.

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SPC Storm Reports from 5 April 2022 note a Tornado hit Allendale SC shortly before 2000 UTC. The animation above shows the ProbSevere (version 2 — available online here) display prior to and just after the tornado. NOAA/CIMSS ProbSevere identifies and tracks the radar feature associated with this tornadic storm. ProbSevere is designed to give forecasters more confidence in warning issuance. ProbSevere in this case highlights the radar object associated with model fields and satellite/radar observations that are most suggestive of a storm supporting tornadogenesis — note that ProbSevere values in adjacent cells are smaller. A meteorogram of this radar object, shown below (and available here), shows the ProbSevere components, and also ProbHail/ProbWind/ProbTor/Probsevere values, for both versions 2 and 3. ProbSevere values increased at around 1930 UTC. ProbSevere v3 values generally are smaller than ProbSevere v2 values; ProbSevere v3 will be demonstrated this year at the Hazardous Weather Testbed (HWT) this year. (Click here to view the Charleston, SC (KCLX) radar at 1958 UTC; a pronounced hook is apparent)

This tornadic cell stood out in the visible imagery. GOES-16 Mesoscale Sector #2 on 5 April included portions of South Carolina. The mp4 animation below, from the CSPP Geosphere site, (this direct link to the animation will be valid for a bit less than a week) shows the tornadic cell erupting at around 1930 UTC near the Georgia/South Carolina border.

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Observations — satellite and radar — both showed the obvious storm. How did short-range guidance perform? A Polar Hyperspectral modeling system — also to be demonstrated at the Hazardous Weather Testbed — produces hourly 18-hour forecasts with initial fields influenced by Sounder Data from the Polar Orbiting satellites Suomi-NPP, NOAA-20, Metop-B and Metop-C. Infrared sounder (CrIS on Suomi/NPP and IASI on Metop) and Microwave sounder (ATMS on Suomi/NPP, AMSU/MHS on Metop) data can produce a more accurate initialization of the moisture distribution in atmosphere. The forecast initialized at 1200 UTC for Lifted Index and Significant Tornado Parameter, valid at 18, 19 and 20 UTC — that is, 6-h, 7-h and 8-h forecasts, below, shows increasing instability before the tornado in Allendale.

The model runs initialized at 1700, 1800 and 1900 UTC, showing fields from initialization through 0000 UTC on 6 April 2022, are shown below. Note that the area with a Significant Tornado Parameter signal is mostly confined to southeastern South Carolina — that is, near the coast. Storm reports show that severe weather was mostly near the coast as well.

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These fields are also available in AWIPS via an LDM feed (in preparation for HWT). The 3 images below show changes in the 2000 UTC forecast (from the model initialized at 1400, 1600 and 1700 UTC). The trend towards higher Significant Tornado Parameter over southeastern South Carolina is obvious. Note that Allendale’s location is shown.

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Added: the GLM on GOES-16 saw a dramatic increase in Flash Extent Density with the tornadic storm starting around 1925 UTC on 5 April. (Click here to see a slower animation from 1920 – 1930 UTC)

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