• [KC5FM] The Brainy Bunch - The Official @WeatherBrains Newsletter #Skyw

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    The Brainy Bunch - The Official @WeatherBrains Newsletter #Skywarn

    Posted: 11 May 2022 09:35 AM PDT http://kc5fm.blogspot.com/2022/05/the-brainy-bunch-official-weatherbrains.html

    IF you are a weather enthusiast, professional, or hobbyist, this program
    is for you. There are a number of hams on the panel.

    Show Notes from WeatherBrains 848: Joint Class Chance Hayes, Warning Coordination Meteorologist from NWS Wichita joined us and gave a great
    Preferences Show Notes from WeatherBrains 848: Joint
    Class Chance Hayes, Warning Coordination Meteorologist from NWS Wichita joined us and gave a great
    lesson on how to be a weather spotter! We also had a discussion about the
    April 15 tornado emergency in Arkansas! KAIT-8 Meteorologist Ryan Vaughan talked about how things unfolded with the storms that night. We also began
    a needed discussion on tornado emergencies: What are they? When are they issued? And more! ▪ Increasing QLCS tornadoes in the Plains (15:05)
    ▪ Should there be more stringent guidelines or certifications for storm spotters? (24:00)
    ▪ Anatomy of supercells (47:30)
    ▪ Misperceptions with tornado alley (1:15:00)
    ▪ The Astronomy Outlook with Tony Rice (01:17:18)
    ▪ This Week in Tornado History With Jen (01:19:32)
    ▪ National Weather Round-Up
    ▪ E-Mail Segment (No segment this week)
    ▪ Increasing QLCS tornadoes in the Plains (15:05) ▪ Should there be
    more stringent guidelines or certifications for storm spotters? (24:00)
    ▪ Anatomy of supercells (47:30) ▪ Misperceptions with tornado alley (1:15:00) ▪ The Astronomy Outlook with Tony Rice (01:17:18) ▪ This Week in Tornado History With Jen (01:19:32) ▪ National Weather
    Round-Up ▪ E-Mail Segment (No segment this week) Check out the show here or on your favorite podcast app! Coming Up on Episode 849 Monday, April 25, 2022 at 8pm ET / 7pm
    CT We continue the discussion on tornado emergencies and the entire warning process! From
    the WeatherBrains Archives Jason Samenow from the Capitol
    Weather Gang was our Guest WeatherBrain in April of 2015! Check out WeatherBrains 483: Very Chaotic Start This Week's Brainy Article from James Aydelott After Episode 846
    about the March 30th Springdale Tornado, friend of the show James Aydelott
    sent us some of his thoughts on the event. He has put together some great explanations of some of the radar data in this week's article. If you
    missed our show with Dan Skoff and Mike Susko of KNWA-TV, check it out
    here! And here is James' Guest Article Entitled: I hate QLCS tornadoes.
    Hate with the burning fury of a thousand suns. 1) That was some NASTY Non-Uniform Beam filling (NUBF) in the dual pol
    products. Non-Uniform Beam Filling occurs when a mixture of precip types
    occurs in the radar signal. It shows up as spokes of low correlation coefficient along the radar azimuth. The radar location (KSRX, Fort Smith radar) is in the worst spot to have that spoke of NUBF data be an issue
    with a north to south storms directly north of the radar. There are several high reflectivity cores that develop or are ongoing in the line which are causing the NUBM. Non-Uniform Beam Filling
    Spokes One of these cores, depicted in the reflectivity data shown, had some rotation in it too as it reoriented NW/SE, just a few miles northeast of the tornadic circulation. The tornado itself appears to have formed just southwest of that NW/SE core, w/ the rotation increasing
    rapidly during the 09:01:07 volume scan from KSRX (Fort Smith radar). To further complicate things: just as the Tornado Debris Signature (TDS) is in
    the "unloading the debris" phase as the tornado lifts and the storm unloads
    the lofted debris (spreading out of the TDS), another core just north of
    Fort Smith throws another spoke of NUBF right through the
    TDS!!! NUBF spoke through the
    TDS! 2) The Tornado Debris Signature (TDS)
    appears on the KSRX 0.5° (lowest) elevation CC data at 09:08:01 product
    time. [verify as a valid TDS by noticing the TDS is in the same spot as the center of rotation (seen on velocity data) and where reflectivity >30dbz], right on I-540. Storm survey says start time was 09:04z, so that checks
    out. KSRX radar view 4:08:01 volume start time. Upper left: Reflectivity, Upper Right: Storm Relative Velocity, Lower left: Correlation Coefficient, Lower right: Normalized Rotation.
    3) KSRX (Fort Smith radar) is in a terrible location for detecting
    rear-inflow jet (RIJ) which is often perpendicular to the line. Doppler velocities only read the true maximum values when wind moves directly
    toward or away from the radar. But, even from KINX (Tulsa) radar, perfectly aligned to view a perpendicular rear inflow jet, I don't see much evidence
    of a localized RIJ surge in higher tilts either, and KINX should've been oriented perfectly for RIJ
    detection. 4) Maddeningly, the magnitude of the rotation decreases on KSRX 0.5° (lowest) elevation storm relative velocity as the tornado touches down!!! Time
    series of Storm Relative Velocity data from KSRX (storm motion used: 227° 33kts) 5) At 09:14:30 (vertical slice image of
    dual pol data – correlation coefficient), the debris was being lofted to around 15,000 feet. (Entremont & Lamb, 2015 paper shows that's high end for QLCS tornadoes, and even when supercell-spawned tornadoes, debris loft to
    that height correlates well for EF2 or EF3 strength. Left: Vertical slice of CC, showing debris loft, Right: KSRX 0.5° elevation Correlation Coefficient Clues, in chronological order. 08:40:54 KSRX volume start time. Take a look at echo tops. The
    highest ET was the part of the line segment which produced the tornado.
    This is a differentiater makes me really focus on this part of the line. It points to this segment as having the most vigorous updraft.
    KSRX, Left: Reflectivity, Right: Echo Tops
    08:59:30 KSRX product time on the 0.5° (lowest) elevation. Normalized
    rotation (NROT) spiked to 1.5. This is the circulation the tornado
    developed from. KSRX Normalized rotation
    09:01:24 KSRX product time 0.5° (lowest) elevation. An area of increased Spectrum Width appears near Underwood Park with an area of increased
    rotation (seen on NROT data). Right on the west edge of a NUBF spoke. The
    other areas of NROT>1.0 were in the NUBF spoke of bad data. I've seen
    spectrum width increases with QLCS tornadoes before, usually co-located
    with the rotation which produces the tornado. It's not a sure fire thing,
    but it's a clue. (into the radar geek weeds here: Spectrum Width is Doppler data that measures the consistency of velocity phase shifts from radar
    pulse to radar pulse, think of it as a reliability check-something chaotic
    is happening in this spot, causing that higher spectrum width, I'm not
    smart enough to know what.) KSRX, Upper left: reflectivity, Upper Right: Spectrum Width, Lower Left: correlation
    coefficient, Lower Right: Normalized rotation
    The 0-3km shear was >40 on forecast soundings on the Oklahoma side of the
    state line, and the environmental winds were really strong, and that's
    always alarming to me in these deep convection scenarios. Weak winds and
    weak shear rarely spin up significant tornadoes. Overall, this was a tough
    one. The non uniform beam filling spokes are a giant distraction. There was
    no obvious localized rear-inflow jet evident on radar feeding west to east
    into the QLCS from KINX (Tulsa radar) or KSRX (Fort Smith radar) looking at velocity data. The hodographs and surface wind were strongly supportive of
    QLCS tornadoes. Lastly, there was a sharp reflectivity gradient on the
    leading edge of the convection, implying fairly unmodified unstable surface
    air was feeding the storm segment's updraft.
    Astronomy Outlook from Tony Rice The Lyrid meteor shower peaks
    this week as the Earth passes through debris left behind by comet 1861 G1 Thatcher. The best time to see meteors is around midnight local time,
    Friday April 22 into Saturday April 23, before moonrise around 2 am. Under
    dark rural skies you may see 15-20 meteors per hour, half that under
    suburban skies. Occasional outbursts of activity, an increase in the number
    of visible meteors, occur. This happened in 1803, 1922, and last happened
    in 1982, so researchers aren't hopeful that another outburst might occur
    again until the 2040's. Predicting when an outburst might occur is
    difficult. Each year, Earth might pass through a different trail left
    behind by comet Thatcher. But the gravitational pull of the planets pull on this debris throughout the year in ways that are hard to predict.
    Researchers think that outburst might be the result of trails merging, if
    just temporarily. While this is not expected this year, the Lyrids are
    worth taking a look at, if just because you don't have to get up before
    dawn and can enjoy the night sky under mild spring
    skies. This Week In Weather History - Courtesy of
    Bill Murray April 21
    1927: Much of the Mississippi River Delta was underwater as the Great Mississippi River flood of 1927 was well underway.
    April 22
    1883: Very poorly documented tornado outbreak across Mississippi on the
    22nd and Georgia on the 23rd killed at least 109 people. Several long track killer tornadoes occurred. April 23
    1927: Flood waters in the Mississippi Delta region of Mississippi covered
    an area 50 miles wide and 100 miles long to a depth or up to 20
    feet! April 24
    1999: Humorous storm report from Grants AR transmitted by NWS: THUNDERING
    ALSO. April 25
    1910: Birmingham AL recorded its latest snow ever. An inch of snow was reported in Lamar County, which killed the young cron
    crop. April 26
    1991: Famous Andover KS tornado tracked 70 mile path, killing 17 people
    and destroying part of McConnell AFB. April 27
    1942: The town of war boomtown of Pryor, OK was nearly destroyed by an especially violent tornado that struck at 4:45 p.m. Central War Time. 52
    people died in the disaster, making it the fifth deadliest tornado in the history of the Sooner state. Upcoming Guest WeatherBrains May 2...Ryan Hall Y'all May 9...Eric Sorenson May 16...History of the Monthly Weather Review May 23...Dennis Feltgen
    Retirement Party --
    Lloyd Colston
    Hamshack Hotline 50052

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