1-minute Mesoscale Domain Sector GOES-17 (GOES-West) “Red” Visible (0.64 µm), Shortwave Infrared (3.9 µm), Fire Power and Fire Temperature images (above) showed an unusual early-morning flareup of the Moose Fire in Idaho on 21 July 2022. The Fire Temperature and Fire Power derived products are components of the GOES Fire Detection and Characterization Algorithm FDCA.

During this brief flareup, the peak values of Shortwave Infrared, Fire Power and Fire Temperature were a rather modest 83.17ºC, 886.98 MW and 845.37 K respectively — however, the fire was hot enough to produce a notable smoke plume that then drifted southeastward. This flareup apparently occurred during a local increase in terrain-driven wind speeds, around the time that the nocturnal temperature inversion was eroding (which aided in the rapid vertical ventilation of fresh smoke).

GOES-17 True Color RGB images created using Geo2Grid (below) provided a clearer view of the smoke plume as it curled southeastward — along with the ventilation of smoke from nearby valleys that had settled into lower elevations beneath the nocturnal temperature inversion.

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An Embraer 175L took off from Tampa shortly before 1900 UTC on 20 July 2022. About an hour into the smooth flight (as shown here, i.e., around 1945-1950 UTC), turbulence injured about 7 passengers that resulted in a diversion to Birmingham AL (news article; Here is the flight path). The animation of true-color imagery, above, taken from the CSPP Geosphere site (link), shows the region of turbulence, a region of strong convection developing west-to-east along a boundary just inland from Gulf Coast from Mississippi to Florida.

The CIMSS Turbulence site (link) shows probabilities of Moderate-of-Greater (MOG) Turbulence. This machine-learning product was developed using satellite imagery and NOAA/NWS Global Forecasting System (GFS) model output as well as observations of Eddy Dissipation Rate (EDR) on board large aircraft (Here is a training video on the product). MOG Probability fields over North America — along with EDR observation points and Pilot Reports of turbulence — from 1750 to 2140 UTC on 20 July 2022.

The CIMSS turbulence site also includes a Midwest sector that shows the Gulf Coast region; MOG Probability contours and observations are revealed for this event with more clarity. The turbulence was observed in between two different regions of higher probability. This matches an observed feature of this product as noted in the training: We notice that often turbulence occurs on the edge of a predicted feature, not in the center. This indicates that an aircraft that skirts just around a known feature is not “in the clear”. That was the case on this day.

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GOES-17 visible and infrared imagery shows Tropical Storm Estelle over the eastern Pacific to the west-southwest of Baja California. Although there are regions of strong convection, satellite presentation of the storm suggests a modest tropical storm. Center-fixing a storm such as this (with just one image vs. an animation!) is complicated by both parallax (GOES-17 is overhead at 0^oN, 137.2^oW) and the lack of an easily-discerned eye feature in this system.

Instruments that view surface winds, via Scatterometry or via Synthetic Aperture Radar (SAR), can offer better center fixes. Consider the toggle below of Radarsat-2 SAR winds over Estelle. SAR Winds (available here; SAR winds over Tropical Systems can be found here.) show a lopsided storm, with most of the strong winds on the poleward side of the center. The SAR winds that use 0.5-degree GFS wind data as a first guess show a characteristic hourglass feature near the center that advertises an ambiguity between the first guess winds and the observations. That feature is missing in the SAR wind field that is a product of the 0.25-degree GFS winds, suggesting that the 0.25-degree wind field is more accurate. Both fields show a rather baggy center at or just south of 20^oN.

Scatterometry from MetopB and HY2B between 1730 UTC 19 July and 0230 UTC 20 July, respectively show a storm moving west-northwest, passing north of 20^oN just after 0230 UTC.

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GOES-18 images shown in this blog post are preliminary and non-operational

GOES-18 Mid-level Water Vapor (6.9 µm) images during the 18 July – 19 July 2022 period (above) showed a series of impulses rotating within the broader circulation of an anomalously-deep low pressure system that meandered over the Bering Strait region. Anomalously-cold air associated with this deep low helped to produce brief periods of unusual July snow at some locations across the Seward Peninsula and northwestern Alaska.

In GOES-18 Air Mass RGB images created using Geo2Grid (below), brighter shades of red highlighted the core of this broad low pressure system, where high-altitude ozone levels were elevated (due to an unusually low tropopause).

In fact, at 12 UTC on 19 July the low 500 hPa geopotential height value of 5269.3 meters from the Nome, Alaska rawinsonde report (above) established a new July record for that site. The 12 UTC sounding also suggested that the tropopause was located at an unusually low pressure level of 483 hPa — such a low tropopause height was supported by NOAA-20 Gridded NUCAPS data from the SPoRT site (below).

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