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Sunday morning, April 28, I worked what turned out to be a significant severe weather event. There were two tornado watches, the first at 200 AM. Two thunderstorm clusters were tracked all the way from the western edge of our county warning area to the plateau. Many warnings were issued, and a large majority were verified with large hail and wind damage reports from several counties. Of note, a tornado touched down 8 miles southeast of Murfreesboro. There were injuries. A tornado warning had been issued, based on velocity images when the storm was in southwest Rutherford County, with approximately 19 minutes of lead time.

The spotters began organizing county-by-county before daybreak, as the storms were moving into our area. In my 8 years in the NWS, I can remember, at most, maybe five events where spotters were as active and as integral to severe weather operations as they were this morning. The fact that our staff performed so well was due in large part to the mobilization and TIMELY reports we received from the spotters, especially the tornado report 8 miles southeast or Murfreesboro. The report came in at 734 AM. It conveyed the kind of information needed with tornado reports. The spotter reported he was under a rain-free base, there was no condensation funnel, but there was debris on the ground. (Later reports confirmed the damage.) Three minutes later, a severe weather statement was issued conveying this information, and 3 minutes after that, a continuation tornado warning was issued for southeast Rutherford and southern Cannon Counties. News of the tornado reached the TV media no more than 5 minutes after the spotter called in his report.

The spotter system worked like a well-oiled machine. Again, I have rarely worked an event (especially early on a Sunday morning) where spotters played a more important role. This is how it is done.

NWS Spotlight

While searching through some old files several weeks ago, meteorologist Mark A. Rose ran across a rather thick folder, containing some articles, photographs, and other documentation regarding the tornado which struck downtown Nashville during the evening of March 14, 1933.

This tornado touched down 4 miles west of downtown at 730 PM, and traveled 45 miles, through Lebanon, and finally lifting southeast of Carthage. The F3 tornado killed 15 persons, and injured another 45. Downtown Nashville would not be struck again by a tornado until April 16, 1998, more than 65 years later.

This edition, we asked Nancy Van Camp, meteorologist from WSMV TV, to describe exactly what she does in preparation for a typical news broadcast. Here is what she wrote.

Before going to work, we typically check out some internet sites and/or The Weather Channel -- just to get an overview of what's going on. If the weather is threatening, we'll go in early and stay late. Usually, we arrive three hours before a newscast, and we stay 8-10 hours. But during severe weather, anything goes. On a weekday, severe weather can require a 12-15 hour shift. On a weekend, I've stayed longer than 24 hours at a time.

Upon arriving at work, we check various pieces of equipment to make sure they're working. The live radar, the "render" computer that constantly imports new satellite/radar images.

Next, we look over model data, NWS discussions, the SPC [Storm Prediction Center] outlooks. From all of this, we create a preliminary 5-day forecast and compare it with the forecast from the previous shift. We tweak the forecast, trying to maintain some level of consistancy with the last forecast we aired. In other words, we make an effort to create gradual changes in the forecast. I try to have a conversation with the NWS forecaster before he or she leaves for the day.

Now it's time to make sure hair and make-up are camera-worthy. It sounds vain. But it's part of the job. For a guy, this is quick. For a woman -- give me about 30 minutes.

Next, we fill out a form with almanac information (highs & lows, records, and precipitation stats), the evening, overnight, tomorrow, and 5-day forecasts. We play with the wording a little, trying to convey the most accurate information with the most brevity. Using a computer, we create a graphic to correspond with each section of the form.

Then we draw -- on paper -- forecast maps with areas of expected precipitation along with frontal positions. From these drawings, we design forecast maps on the computer that will appear in the on-air weather sequence.

At this point, we're about one hour away from airtime. We call up the on-air graphic sequence on the computer and start making decisions about which graphics to retain, which to delete, and which to add to the mix. For example, if conditions are abnormally humid or dry, we may show a map with dewpoint temperatures. We try to eliminate elements not relevant to the current weather pattern, and add those elements that are significant.

We decide what we want to say for each graphic -- sort of a mini-essay for each one. When that map or graphic appears on the air, it serves as a visual cue for the next piece of verbal information. Some viewers are under the impression that weather is scripted. Not so. We have a plan -- an outline -- but the whole presentation is ad-libbed.

Five to ten minutes from air-time, we enter the studio, put on a microphone, ask for a mic check, and put in the IFB (the earpiece through which we hear on-air audio and instructions from the producer).

We tell the floor crew to pass on to the director which computers to bring up on air for "first weather." First weather only runs about 30 seconds and gives viewers a hint of what's to come in the 5-day forecast.

Three or four minutes after the show begins, we run the airport weather observation into the control room, so a last minute graphic can be made for that.

We still have a few minutes before first weather hits. I rehearse what I'll say, and jot down a few words that serve as a minimal outline.

After first weather, we're about five minutes away from a weather tease. I plan what to say for that. It's brief. Only five to eight seconds.

After the tease, we're only a commercial break away from the main weathercast. (The main weathercast lasts about three minutes.) During the commercial break, cameras are getting set-up. The producer is telling me which live view of the city we'll use. The producer may tell me I have 30 more seconds to use -- or 30 fewer seconds to use.

The National Weather Service in Nashville went online with its web-based meteorology library this year.

Founding members of the Outreach Team are Michael Davis, Sam Herron, Jerry Orchanian, Mark Rose, and Jason Wright, with John Gordon leading the team. In the past few months, both John Gordon and Jason Wright have been promoted to positions at other offices. These hard-working gentlemen will be missed by the Outreach Team and the entire Nashville office.

Actually, we have two photographs of the quarter, although they depict the same phenomenon. These black-and-white snapshots were taken at the Old Hickory office by meteorologist Bobby Boyd in April, 2002. Both photographs are looking toward the west-northwest. This is a rain shaft, or series of rain shafts. (By the way, that is the Doppler radar dome on the right.) What is interesting about this image is the phenomenon occurring on the south (left) edge of the rain shaft. This is called a rain foot, so named because the rain near the surface has begun to spread out, giving a curved appearance to the edge of the shaft, somewhat resembling a foot.

This feature is resolved a little better in the second photograph, zoomed in on the southern portion of the rain shaft. A person standing immediately south of the shaft would experience strong, gusty winds prior to and coincident with the onset of heavy rainfall. Such a phenomenon is known as a "wet microburst," which can produce damaging winds, although in this case, surface winds were likely not that strong. Still, such images are not captured on film very often, and that is why we have made this the photograph of the quarter.