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Lesson 02 of 0720 minBeyond SKYWARN

Spotters, chasers, and what "trained" means

Three kinds of people stand under the same storm with three different sets of obligations. Which one you are changes what a forecast office does with your call.

By the end of this lesson
M1.2.aDistinguish stationary spotters, mobile spotters, and storm chasers by role and obligations.
M1.2.bState what "trained spotter" means in an NWS report, and why it changes how a report is weighted.
M1.2.cExplain what WxAlerts certification is and isn't. Not SKYWARN, not NWS-affiliated.
M1.2.dIdentify the credibility costs of bad reports: false tornado reports, and inflated hail sizes.

Who actually spots

The Field Guide does not describe a hobbyist. It lists public safety officers, amateur radio operators, truck drivers, mariners, pilots and emergency management staff. Most are already outdoors and already on a radio when the storm arrives. Spotter networks are organised through emergency operations centres and Amateur Radio Emergency ServiceOrganised volunteer radio operators who run communications during emergencies, including many severe weather spotter nets. nets, which is why the reporting culture runs on radio discipline.

Stationary, mobile, chaser

Stationary spotter
Works a fixed, known location, usually as part of a net. The office knows exactly where the report came from, which is most of what makes it usable.
Mobile spotter
Moves within an assigned area under a net, reporting position along with the observation. Coverage in exchange for a harder location problem.
Storm chaser
Self-directed, on no net, with no obligation to be in any particular place. Often the closest observer to the storm, and the hardest report for an office to weigh.

None of these is a rank. The difference is obligation, not skill. A net knows where its spotters are and can ask them a question. A chaser outside a net has to supply that certainty in the report itself: position, time, and what was actually seen.

What "trained spotter" means in a warning

When a warning names a trained spotter as its source, that is a statement about the reporting standard the observer was taught: what to call a A localized, persistent lowering beneath the updraft base, on the rear inflow side of a storm, marking where air is being drawn up. Not all of them rotate, and a rotating one is what you report., when a funnel becomes a tornado, how to give a location and an occurrence time. It is not a judgment of your ability. It says your vocabulary matches the office's, so the report can be acted on without a call back to clarify it.

What this certification is, and is not

Use the wording below when someone asks what this certification is. It is the part people most often get wrong in public.

In practice: describe yourself as a WxAlerts certified spotter, never as NWS-trained or SKYWARN-trained unless a forecast office has actually trained you. If both are true, state them separately.

What a bad report costs

  • A false tornado report can put a warning on a storm that did not need one. It is also the fastest way for an office to stop trusting a source, and the next person reporting from your network pays for it.
  • An inflated hail size is the same problem, quieter. Sizes drift upward when they are estimated against memory instead of measured against an object, and everything downstream that uses the record inherits the drift.

On 12 December 2015, an experienced chaser reported two tornadoes in the eastern Texas Panhandle. NWS Amarillo answered him in public, in real time: "There is no storm where you are located. This is NOT a valid report." No Severe weather is happening or about to happen for the people inside a drawn polygon. Issued by the local forecast office. It means act now. was issued. Another chaser posted video of a tornado north of McLean shortly afterwards. Later that evening, the same office filed this:

2353  9 W KELLERVILLE  GRAY CO  TX  35.37N 100.66W
      BRIEF TORNADO TOUCHDOWN AS SHOWN IN STORM
      CHASER VIDEO. (AMA)
Storm report filed by NWS Amarillo for 12 December 2015, as it appears in the Storm Prediction CenterThe national office in Norman, Oklahoma that issues severe weather outlooks, mesoscale discussions and watches. It does not issue warnings. reports archive. Time is UTC. Chasers reported two tornadoes that evening; this is the one that reached the record.

The touchdown time on that report is 15 minutes before the reply above. It reached The official national archive of significant weather events and their impacts, published by NOAA and built largely from local storm reports. It is the source almost every long-term severe weather statistic comes from. as an EF0, 0.04 miles long, no damage, source listed as storm chaser. The observation was correct and the office was reachable. What was missing at the moment it mattered was any basis for acting on it, and video produced afterwards cannot be put back into a warning that was never issued. That is the problem a documented reporting standard exists to solve: it is what makes your report usable before anyone knows whether you were right.

Knowledge checkNot graded · the exam draws a fresh variant of this item

You are watching a livestream that clearly shows a funnel about 30 miles from where you are sitting. Is this your report to make?

Think about what the office has to be able to do with the report once it arrives.
Sources for this lessonNWS Weather Spotter's Field Guide (YPA-201154, 2011), section 1Doswell, Moller & Brooks 1999, Wea. Forecasting 14, 544–557: "Storm spotting and public awareness since the first tornado forecasts of 1948"SPC storm reports for 12 December 2015, tornado report filed by NWS Amarillo@NWSAmarillo reply to @stormpics, 13 December 2015 00:08 UTCNCEI Storm Data, December 2015: Gray County TX, EF0 at 1753 CST, 9.9 ESE Lefors

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