The National Weather Service forecast office on Guam has a Direct Broadcast antenna, and CSPP software takes the downloaded signal and creates useful imagery. The example below shows JAXA’s GCOM AMSR-2 imagery at 36.5 and 89.0 GHz, and the structure of the low-level circulation (36.5 GHz) and upper-level clouds (89.0 GHz) are apparent. In the 36.5 GHz imagery, it’s likely the orange/red features are rain-producing clouds The 89.0 GHz imagery is coldest (yellow and red in that enhancement) where ice features are present because ice scatters 89.0 GHz energy very effectively. (The Joint Typhoon Warning Center has information on this storm here).

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Thanks to Douglas Schumacher, CIMSS, for forwarding along this imagery. But what if you don’t have the helpful Douglas to send you imagery? In that case, you can use Polar2Grid to create imagery from files downloaded from JAXA’s GPortal! That website allows a registered users (free registration!) to select specified data from a specific day over a specified region as shown in the succession of screen captures below.

The downloaded data can be processed with Polar2Grid software (using the -r amsr2_lib flag that reads AMSR-2 Level 1b data). This software can then produce imagery as shown below — looking very similar to the data from the Direct Broadcast antenna, but covering a larger area.

A user can then get Himawari data (from, for example, an Amazon bit bucket) and use Geo2grid software to create imagery, shown below, with the same map projection as used for the Polar2grid imagery!

Combinations of Visible and Enhanced infrared imagery with the color-enhanced Microwave data are shown below. The combination of polar and geostationary satellite data yields a more complete understanding of the system.

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MIMIC Total Precipitable Water fields, below, show abundant moisture in the West Pacific including over Marianas Islands and Micronesia. A picture of rain on Guam from the WCM (Thanks Landon!) led me to investigate this system.

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True-color imagery from the CSPP Geosphere site, above, shows 4 named storms — Carlotta, Daniel, Emilia and Fabio — over the Pacific basin on 5 August. It is not common for 4 storms to exist simultaneously! The animation below during the day on the 5th shows the motion of the storms. Although Carlotta and Daniel, and Emilia and Fabio, are within close proximity, Fujiwhara interactions (during which the two storms rotate around each other) do not appear to be occurring.

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GOES-16 Band 2 Imagery from Mesoscale Sector 1, from the CSPP Geosphere site, above (click here for an animation with state/country borders), shows convection developing along the northern shore of Lake Erie and moving into Buffalo. One of these convective towers generated a weak tornado (storm report) at 1649 UTC.

The large-scale environment on this day was not expected to generate tornadoes. The (1300 UTC) Convective Outlook from the Storm Prediction Center, below, in a toggle with the tornado probabilities, showed a marginal risk, and very low tornado probabilities.

GOES-16 Day Cloud Phase Distinction RGB imagery, below, shows the glaciation of the developing convection as it moves out of Ontario, across extreme northern Lake Erie and into New York: the color in the RGB changes from green/cyan to yellow/orange. Note also the large-scale surface convergence in the plotted surface observations: west-southwesterly flow to the south of the developing line, west or west-northwest flow to the north of the developing line.

NOAA/CIMSS ProbSevere (v3) is a Machine-Learning tool that estimates the probability of severe weather. How did it perform in this environment? The animation below shows the ProbSevere polygon from 1535 UTC through 1710 UTC. ProbSevere highlights the cell that produced the tornado, and consistently tracks it through Buffalo.

ProbSevere objects can be probed to show how probabilities are changing, and to show the different observed parameters used to diagnose the probability. Values from 1635-1710 UTC are shown below. ProbTor and ProbHail values peaked at 1700 UTC, ProbWind peaked at 1655 UTC. Both times are after the tornado.

Note in the readouts above the clickable icon that references Object ID# 592509. That click yields a time series of various ProbSevere variables and components that are shown below (there are 4 more shown here). ProbSevere for this object increased at around 1615 UTC, but values are not large. GLM values — in the lower right — showed an increase as the tornado was occurring. This was a very difficult tornado to predict based on the ProbSevere values.

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GOES-16 Day Cloud Phase Distinction RGB imagery is overlain with GLM Flash Extent Density in an animation from 1640-1700. Note that the default AWIPS enhancement for FED has been altered considerably: the maximum value was changed from 260 to 20. FED increases to a peak of 15 at 1655 and 1656 UTC, having risen from 7 at 1649 UTC, the time of the tornado, before falling back to 6 by 1700 UTC. This subtle change is apparent because the default AWIPS enhancement for Flash Extent Density was altered.

The 1200 UTC Buffalo upper air soundings is shown above. Low-level shear is favorable. This tornado appears to have emerged out of a Lake-influenced circulation within broad convergence and its very small scale nature makes its affect on satellite imagery a distinct challenge to interpret.

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Added: It’s curious that this event occurred on the same day as the packet of gravity waves that developed over Michigan hours earlier (blog post). I tried very hard to see if there was a direct link between that event and this one. I didn’t find one.

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Strong convection developed over southern Lake Michigan early in the morning on 5 August, as depicted in the animation above. Multiple pilot reports of moderate turbulence occurred in/near the developing convection. Gravity waves developed on the upwind side of the deep convection, shown in the enhancement above as darker blue (that is, warmer brightness temperatures); the circulation with the gravity waves had an observable effect on approaching clouds as well. Note, for example, how the convection initially on the eastern central Lake Michigan shoreline (highlighted by the black arrow in the animation below) dissipates as it moves under the gravity wave structure. Clouds moving in from the northwest also change abruptly as they encounter the gravity wave barrier (and its vertical circulation).

Weighting Functions from the 1200 UTC Detroit Rawinsonde site, below (source), show contributions to the signal in the Band 8 water vapor imagery originating from a layer between 500 and 200 hPa.

The strong convection formed in the exit region of a 100-knot jet at 200 mb as shown in the analysis below. Note the large scale difluence in the region: north-northwest winds (40 knots) at Lincoln, IL; Northwest winds at 55 knots at Detroit MI; West winds at 65 knots in Maniwaki, QB!

The CIMSS Turbulence Product — that predicts via a Machine-learning algorithm the likelihood of Moderate or Greater (MOG) turbulence — increased markedly as the convection developed, as shown below.

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GOES-16 Visible imagery, below (from the CSPP Geosphere site), also shows the gravity waves, and their interaction with/affect on convection.

I am grateful to Greg Mann and TJ Turnage, Science and Operations Officers (SOOs) in Detroit and Grand Rapids, respectively, for their comments on this event (and for letting me know about it!)

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