Tornado Forecast verification?

Spring tornado outbreak forecast posted on the 2nd, below the verification updates,

Cost to public a couple clicks of the mouse,
to compare to my sites maps so far;

2-24=27 tornado reports  110224_rpts.html

2-25=1 tornado report  110225_rpts.html

2-27=18 tornado reports 110227_rpts.html

2-28=18 tornado reports 110228_rpts.html

3-05=10 tornado reports  110305_rpts.html

3-06=3 tornado reports 110306_rpts.html

3-08=19 tornado reports   110308_rpts.html

3-09=25 tornado reports  110309_rpts.html

3-10=4 tornado reports   110310_rpts.html

3-14=2 tornado reports   110314_rpts.html

3-18=1 tornado report   110318_rpts.html

3-19=1 tornado report   110319_rpts.html

3-21=1 tornado report   110321_rpts.html

3-22=19 tornado reports   110322_rpts.html

3-23=8 tornado reports  110323_rpts.html

3-26=8 tornado reports  110326_rpts.html

3-29=5 tornado reports  110329_rpts.html

3-30=1 tornado reports  110330_rpts.html

3-31=6 tornado reports  110331_rpts.html

4-4=67 tornado reports  110404_rpts.html

4-7=1 tornado report   110407_rpts.html

4-8=3 tornado reports  110408_rpts.html

4-9=32 tornado reports  110409_rpts.html

4-10=24 tornado reports  110410_rpts.html

4-13=1 tornado report  110413_rpts.html

4-14=27 tornado reports  110414_rpts.html

4-15=120 tornado reports   110415_rpts.html

4-16=120 tornado reports   110416_rpts.html
Richard Holle says:
March 2, 2011 at 12:32 pm
Tornado production is a result of Lunar declinational tides pulling air masses from more equatorial areas into the mid-latitudes, so the peak production times when they form can be predicted as the periods from Maximum North culmination to three days after, a couple of days when the moon crosses the equator headed North, and as the moon reaches maximum South declination and several days after.
These effects are due to the production of the primary and secondary tidal bulges in the atmosphere, that arrive at the same time as the ion content of the air masses reaches a local maximum. Between the induced charge differential between the +ion concentrations riding on the more equatorial sourced air mass, established ahead of the dry line front of -ion concentrated more polar air mass, that sweeps in from the West, forcing the precipitation into the rapidly moving narrow band of severe weather from which the tornadoes form on the trailing edges.
The periods when these effects will be most likely to occur this spring,
2-25/28 for three days, which we just had, around max South.
3-5/7 slight chance of small outbreak
3-12/17 starting in Arkansas through Kentucky and the Ohio river valley
3-25/30 Starting Texas/Oklahoma/Arkansas through Ohio river valley the beginning of a long period of very wet activity most of April.
4-5/8 start up of activity
with the re-enactment of the 1974 outbreak most possible in the period
4-8/13 Maps of the expected precipitation can be found on my site, bearing in mind that the tornado and severe activity usually forms in the fast moving part of the frontal boundary and not usually in the areas of heaviest total daily precipitation.
On the maps show on my site you can expect to see the tornado development in the areas with the “netted” looking precipitation patterns due to the usual nature of the part of the front where they occur.
1974 is one of the analog years for my forecast method, which is why I mention we may see a replay of that out break.

[for what its worth NOAA changed the way it reports # of storm reports]

On 31/03/2011, at 5:13, David Imy <> wrote:


This is very important and may through a kink in your hail study.  We changed the way we report severe events and starting on March 8, 2011, we no longer use the proximity space/time rule to de-duplicate events and minimal filtering is now applied to the decoded reports. This means if a duplicate report is sent, it will be encoded twice on the storm reports page and count as two events (when in reality it is only 1). Also, prior to March 8th, if the same hail or wind event occurred  with 10 miles or within 15 minutes of the same event, it was not logged onto the Storm Reports page (assumed to be the same storm report). These two factors will result in many more wind and hail reports than in the past (neither correct or incorrect), though the user has to dig more through the actual reports, as opposed to using the actual numbers. This is not a conspiracy against your project, but a request from many of our users that has been in the works for some time.  Anyway, I wanted you to be aware.


Filed under: In other online forums,Natural Disasters,Natural Processes,Tornadoes — by Richard Holle @ 8:53 pm on April 16, 2011


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