Annual Skywarn training should be provided for Amateur Radio volunteers by an instructor whose credentials are recognized by the local National Weather Service.   While training varies from location to location based on local conditions, the typical Basic Skywarn program should consist of the following subjects:

   1)    The Basic Thunderstorm Cell - how it works.

    2)    An introduction to the concept of a spectrum of four basic thunderstorm types:

                A)     Single-Cell Storm
                B)     Multi-Cell Cluster Storm
                C)     Multi-Cell Line Storm (Squall Line)
                D)     Super-Cell Storms.

    3)    The Super-Cell Storm.
                A)     It's environment
                B)     The location of major storm features
                C)     The dynamics of Super-Cell Storm
                D)     The importance of the Rain-Free Base
                E)     The characteristics of the Tornadic Wall Cloud
                F)     The characteristics of Tornadoes and Funnel Clouds

   4)    The structure of the Squall Line (Multi-cell Line Storm) including:
                A)     The structures of the Squall Line
                B)     The dynamics of the Squall Line
                C)     Updraft/Downdraft Interface
                D)     Locations of major storm features

    5)    Spotter Criteria ("what to report")

    6)    Spotter's "Quiz" - so students can test their knowledge.
                A)     Tornado lookalikes
                B)     Scud Cloud, Rain Shafts
                C)     Various storm features

Many NWS Offices also offer an Advanced Spotter Training Program.  While not absolutely necessary to perform effectively as a Skywarn Spotter, attendance at such training programs should be encouraged by all ARES Emergency Coordinators.  In general, the Advanced Spotter Training familiarizes the student with:

   1)    A detailed look at the environmental conditions in which each of the following types of storms occur:
                A)     Single Cell Storm
                B)     Multi-Cell Cluster Storm
                C)     Multi-Cell Line Storm
                D)     Super-Cell Storm

    2)    The effects of Draft strength on Storm Severity

    3)    The effects of Vertical Wind Sheer on Storm longevity.

    4)    A detailed look at each of the four major thunderstorm types including:
                A)     Storm Structure
                B)     Environmental Condition
                C)     Spotting Considerations
                D)     Hazard Analysis

    5)    Super-Cell Variations:
                A)     Review of the "classic" Super-Cell
                B)     The Low-Precipitation Super-Cell
                C)     The High-Precipitation Super-Cell

    6)    Downdraft-related severe weather events.
                A)     Downburst
                B)     Microburst
                C)     Macroburst

How Skywarn Nets Operate:

It is the responsibility of the Net Manager to insure that the majority of information flow is from the field to the NWS in the form of accurate, timely, and necessary severe weather reports.  As a general rule, the following information is of importance to the NWS:

Winds in excess of 58 MPH (50 knots)

1. Hail in excess of  inch in diameter
2. Wall Clouds
3. Tornadoes
4. Funnel Clouds
5. Flash Flooding
6. Rainfall in excess of 1 inch per hour.

In some cases, the NWS may set slightly different "thresholds" for such information as hail size or wind velocity, but these items listed above are excellent guidelines for any Skywarn net.

Some information, which is of little value and should therefore be discouraged (particularly when severe storms are imminent), may include:

1. Rainfall arrival
2. Moderately gusty winds
3. Lightning
4. Scud Clouds
5. "SLC's" ("Scary looking clouds")

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The "TEL" System:

Reports should be transmitted to the NCS using the "TEL" system.  This stands for:

TIME at which the storm feature was observed
EFFECT which was observed
LOCATION of the storm feature

Optional information includes the estimated direction and speed of movement.

For example:

This is... W8IHX, at 535 PM a Wall Cloud at I-35 and 6th Street
This is... WB8SIW at 603 PM a Funnel Cloud at Congress and River moving Northeast.

Skywarn spotters are encouraged to practice formatting reports in this fashion during drills and exercises.

Skywarn Numbers:

While the EC for a smaller community may know each volunteer and his capabilities personally, Skywarn programs in larger metropolitan areas may wish to issue a "Spotter ID" number for use by Radio Amateurs when checking-in to the net.   This assures the NCS that the individual from whom he receives a report has had the minimum training necessary to insure accuracy.  This number may include an indication of whether the individual has had basic or advanced training.

False Reports:

The fact that a volunteer has had Skywarn training does not guarantee competency.   It is therefore necessary for all NCS operators to have a thorough understanding of storm structure and dynamics.  This will allow them to "sift" through any false reports they may receive by comparing reports against their knowledge of where various storm features are most likely to occur.  Ideally, NCS operators and key ARES personnel should have Advanced Skywarn Training as well as extensive field experience.

Some typical situations which may generate false reports include:

The "Wall Cloud"

Research has shown that inexperienced spotters may confuse the Shelf Cloud, often located at the leading edge of the storm, with the "Wall Cloud" which is an isolated lowering of the Rain Free Base at the storm's rear flank.  NCS operators should compare the location of those individuals reporting Wall Clouds against radar images showing the storms relative location.  If the wall cloud report is coming from the leading edge of the storm, it is quite likely false.  Wall Cloud reports from the Southwest edge of a storm, particularly if located beneath a rain-free base should be taken very seriously.

Remember the definition of a Wall Cloud:  An isolated lowering of the rain-free base typically one to three miles in diameter.

One way to detect the differences between wall clouds and shelf clouds or other storm features is to be thoroughly familiar with the characteristics of each.  For example:

Wall Cloud Characteristics:

1. Wall Clouds typically occur at the Southwest edge of a storm beneath the Rain-Free Base.
2. Wall Clouds slope upward away from the Precipitation and suggest inflow.
3. Tornadic Wall Clouds tend to rotate and often exhibit persistence in excess of 10 or more minutes.
4. Airflow is typically into a Wall Cloud (inflow) when it is viewed from the East or Southeast storm flank looking West.

Shelf Clouds:

1. Shelf Clouds typically occur near the leading edge of the storm or immediately adjacent to a precipitation area.  In particular, watch the East flank of the storm for a Shelf Cloud.
2. Shelf Clouds typically slope downward away from the precipitation area and suggest outflow.
3. Shelf Clouds may appear vaulted when viewed as they moved overhead.
4. Precipitation typically falls immediately behind an advancing Shelf Cloud.

Rain Shafts ("Virga")

Rain Shafts are occasionally mistaken for Funnel Clouds or Tornadoes.  Rain Shafts tends to be somewhat transparent in character.  Unlike a tornado, they will not show evidence of inflow, rotation, or debris.

If a spotter reports a tornado under questionable circumstances, it may be wise for the NCS operator to as the following questions:

1. Where within the storm is the feature located?
2. Is rotation present?
3. Is a debris cloud present?

Please take a look at the attached "Flow Chart" diagrams for use in determining the accuracy of Funnel Cloud and Wall Cloud reports.

Scud Clouds:

Scud Clouds, occasionally called "wind Clouds" are pieces of detached cloud, which form when cool outflow air is injected into an area of warm moist air adjacent to a thunderstorm.  Occasionally, when viewed from the correct angle, this scud cloud may be mistaken for a significant storm feature such as a Funnel Cloud, Tornado, or Wall Cloud.  Again, it is important for the NCS to seek clarification when such reports are in doubt.

1. Consider the location of the reported feature with respect to overall storm structure.
2. As the reporting party key questions which may help clarify his report.

Careful monitoring of reports by the NCS will not only protect the reputation of the ARES group providing the service, but will prevent false warning from being issued to the public.  The purpose of the Skywarn program is to not only improve warning time, but also improve warning accuracy!

When should a net be called?

A common question from many ARES Emergency Coordinators or Net Managers involves guidelines for calling a directed net for Skywarn events.  As a general rule, it is unwise to call a Skywarn net too far in advance.  There is no surer way to discourage volunteers than to make them sit at spotter locations for a couple of hours awaiting storm arrival.  A Tornado Watch or Severe Weather Watch may be issued several hours in advance of storm arrival.  Therefore, the following general rules are applicable to all Skywarn Nets:

It is suggested that guidance on when to activate be obtained from the meteorologist on-duty at your local NWS office.

1. EOCs and key stations should be activated approximately one hour in advance of anticipated storm arrival.
2. Spotters should be placed on active status approximately one hour before the storms reach the nearest point within the area of warning responsibility (County or City).

Generally, Standard Operating Procedures should call for a net to be activated during the following conditions:

Tornado Watch
Tornado Warning
Severe Thunderstorm Warnings

Depending on the guidance received from National Weather Service, Skywarn Spotters may be placed on Stand-By status for a Severe Thunderstorm Watch.

Whenever advance notice is given of an impending severe weather event, it is wise to arrange for staffing of key stations at such facilities as EOCs, the NWS office, or other served agencies.

Some National Weather Services offices transmit "Severe Weather Potential Statements" around noon each day during the severe weather season.   These bulletins, often available over NOAA Weather Radio or similar services, should provide excellent guidance for ARES leadership officials.  When severe weather is anticipated in the area, it is advisable to notify key personnel so that they will be ready to proceed to their posts should a Tornado Watch be issued.

Net Logs and Forms:

NCS operators and key stations should maintain a log of all radio activity.  This should include:

The time at which each station reports into and out-of the circuit.

The location of each spotter.

The time each effect is reported along with the description of that effect.

Special forms may be prepared through which significant reports can be transmitted in writing within an EOC to emergency management officials through a simple "fill-in-the-blanks" message format.  Typical reports are simply "checked-off" and only the time, location, and call sign of the reporting station need be filled-in.

It is important to remember that an accurate and neat radio log protects the ARES program from liability should a report be misinterpreted or lost during a busy severe weather event!  Because of the speed at which severe weather may move through the area, it may be wise for NCS operators to develop the skills necessary to keep a long on a typewriter or computer.

Spotter Safety:

Spotters should select locations, which provide access to a safe area, such as a nearby public building.  Consider spotter locations near a fire station, school, business, or home.  However, it is also important to remember that, to be effective, a spotter should have a clear view of the Western Sky and horizon.  If a solid building is not available near a spotter location, then a plan of escape should be in place or, at a minimum there should be access to a ravine, culvert, or highway overpass.

Spotter Equipment:

Generally, in addition to radio equipment, a spotter should have access to the following materials and equipment:

1. Detailed map of the surrounding area
2. Spotter ID, RACES, or ARES ID Card
3. Amateur Radio License
4. Rain gear
5. Flashlight
6. Field Glasses ("binoculars")

It is also wise for the spotter, or any active ARES or NTS operator, to have access to a set of basic emergency equipment, such as spare batter packs, a portable two-meter antenna, message forms, pens and pencils, and so forth.  This equipment may be arranged in the form of a "jump-kit" which can be kept in the car or carried to work and therefore available at all times should an emergency arise.

Storm Damage Reports:

Spotter groups are encouraged to accumulate reports of significant storm related damage.  Some examples of significant damage may include:

• Trees down
• Damage to infrastructure
• Damage to substantial structures (homes, barns, etc.)
• Flooding
• Injuries or fatalities (do not refer to specific individuals).

These reports may be transmitted to the NWS within 24 hours after the event.   However, it is important that the time at which the event occurred be included in the report accurate to within just a few minutes.  These reports are critical to the storm verification process, which the NWS must conduct aft5er a warning has been issued.

An excellent method for the transmission of storm damage reports may be had through the use of the NTS radiogram format.  This standardized format provides the NWS with much of the information they need when reviewing storm damage reports, such as place or origin, date and time of origin, the name of the reporting individual and so forth.

The Supercell Storm

What to Report

• Tornado or Funnel Cloud
• Wall Cloud
• Hail in excess of inch in diameter
• Damaging winds:  +50 knots (58 mph)
• Flash FLooding
• Significant Storm Damage

Use the TEL System:

Time of observation
Effect or Storm Feature Observed
Location of Storm Feature

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Guide for Estimating Wind Speeds

25 to 31 mph:
Large Branches in motion; Whistling heard in telephone wires.

32 to 38 mph:
Whole trees in motion; inconvenience felt walking against the wind

39 to 54 mph:
Twigs break off trees; wind generally impedes progress

55 to 72 mph:
Damage to chimneys and TV antennas; shallow-rooted trees pushed over

73 to 112 mph:
Peels surface off roofs; windows broken; cars pushed off roads

113 to 157 mph:
Roofs torn off houses; large trees uprooted; mobile homes destroyed

Squall Line Thunderstorms

• The Updraft is typically llocated in a contnuous curtain along the leading edge of the storm.
• Watch the leading edge of the storm for possible damaging straight-line winds or a rare gust-front tornado. 
• Remember that it is rare for a tornado to occur at the leading edge of the storm.  If one does occur it is likely to be weak and short-lived.
• Occasionally, a Roll Cloud will form ahead of the Squall Line in association with the Gust Front.  This long horizontal cloud is NOT a tornado!
• The strongest winds usuall occur a few minutes after the Gust Front passes or just before rain and hail begin.
• Watch new cells forming at the Southwest edge of a Squall Line closely.  They may be more severe!
• Watch areas near a break in the Squall Line closely.  These cells may be more severe!
• A Bow in the Squall Line indicates a greater potential for damaging winds.  Watch these areas carefully! 

_{Guide for Estimating Hail Siz}Guide for Estimating Hail Size

Pea Size	inch
Marble Size	inch
Dime Size	inch
Quarter Size	1 inch
Golfball Size	1 inch
Baseball Size	2 inch

Wall Cloud Flow Chart

When a questionable Tornado report is received, ask the following questions:

Tornado Safety

• In the home, go to the basement or a small interior room nearest the center of the lowest floor.

• If caught outside, seek shelter in the nearest ditch or ravine.  Stay as low as possible.

• Do NOT stay in mobile homes or vehicles.   Leave and take shelter elsewhere!

• Do NOT try to out-run a Tornado in your automobile.  Seek Shelter instead!

Skywarn Net Report

Use the following form as a record of observations, and also as a standard format for calling in observations on the radio.