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Severe Weather Net Procedures

Hancock County Amateur Radio Severe Weather Net
Greg Chaney, ARES Emergency Coordinator, N9MOX

Date: June 22, 2008
To: Hancock County Amateur Radio Operators
From: Greg Chaney, ARES Emergency Coordinator
Subject: 2008 Severe Weather Net Procedures

Welcome to the 2008 severe storms spotting season in Hancock County. I trust that our weather spotting activities will be safe, accurate, timely, valuable to the National Weather Service and to Hancock County, and, most of all, enjoyable for the participants.
As amateur radio weather spotters, we provide a valuable service for the NWS and for Hancock County. That has been proven time and time again. But for most of us, amateur radio is a hobby and weather spotting is something we do as part of our hobby. Sure, we want to contribute to the good of the county and to local weather forecasting, but if we don’t have a good time, we aren’t likely to stay in the program. If you aren’t having a good time, let us know. Our net control operators, our HARC officials, and myself are here to help.

First off, I encourage everyone to participate, regardless of his or her club or organizational affiliations. Severe weather spotting in my opinion crosses the lines of RACES, ARES, and any other organized amateur radio group. The purpose of severe weather spotting is to report on severe weather activity. You do not have to be a member of any particular club or organization to participate. All you have to do is show a dedication to the task at hand, display a willingness to follow procedures (and be constructively critical of those procedures if you see a problem with them), and adopt an attitude that we are all here to work together.
Secondly, severe weather spotting is not a competition. There is plenty of room elsewhere in amateur radio for contests, awards, and prizes. There is no special recognition for the number of tornadoes spotted or the highest measured wind gust. And there certainly is no recognition for inaccurate, incomplete, untimely, or, worst of all, false reports. Our recognition is a pat on the back and a “job well done” delivered by the NWS or by the county.
Thirdly, we will continue to work a plan to get our nets up and running before the weather service calls. Our plan empowers the hams in this county to initiate weather nets using very simple criteria so that we can have our people into position and ready when the weather service calls. This plan is triggered by severe weather announcements from the National Weather Service, which are available to just about anyone. Once a net is initiated, it can proceed and advance in tune with the developing weather patterns. The key, from our standpoint, is to try to be one step ahead of the weather service.
So, to those of you who have been regular participants in Hancock Country Severe Weather Net, I’m glad to have you onboard! I’m counting on you to uphold our fine tradition and to help bring along those folks who are new to the program. To those of you, who are new to HCSWN, welcome! We are always glad to see new people involved in our program. There’s a lot to learn, some of it may be a bit overwhelming, but just take things one-step at a time, and soon you will be an old hand. To those of you who participated in the past, but drifted away for whatever reason, welcome back! Some things have changed; some things have stayed the same. Our purpose hasn’t changed, though, and that is to provide the best amateur radio weather spotting around.
My many thanks to Bob Burns, N9KRS, for graciously allowing me to steal his Skywarn procedures from his Hendricks County SKYWARN website. As you can see a great deal of time and effort was required to produce the original document and procedures.
Now, the details of Hancock County Severe Weather Nets for 2008

How are we organized?
Operationally, we act in cooperation with the National Weather Service. We report to the NWS Forecast Office in Indianapolis and they give us direction regarding where to look and what to report. In Hancock County, Skywarn is an outgrowth of ARES and HARC activities, though we are not specifically or exclusively a function of those groups.
How do you prepare for the net?
The bare minimum for participating in the net is a radio capable of operating effectively on the net frequencies.
Here are some additional suggestions for your home station:
• A radio capable of operating on battery power. This can be a handheld or a base/mobile rig with appropriate batteries. Make sure your batteries are charged and make sure you have spare or backup batteries on hand.
• An indoor antenna.. A ¼-wave mag-mount antenna on a refrigerator or steel file cabinet should work well, too.
• A pad of paper and a pencil.
• A county map.
• A rain gauge and/or other weather measuring instruments.
• Binoculars if you have a view of the distance that isn’t blocked by nearby trees or buildings. Be careful with binoculars since looking towards a lightning strike with binoculars can dazzle your eyes.
• A copy of the NWS Spotter’s Guide ( and the Advanced Spotter’s Field Guide (
• A radio/antenna capable of reaching the 146.970 repeater or access to a telephone in case the Net Control assigns you a special task.
If you plan to go mobile, the list is basically the same, but with a few additions and modifications:
• Our repeater’s coverage has been vastly improved with it’s location at 500 N and 300 E. My thanks to HARC, the repeater committee, Hancock Rural Telephone and Central Indiana Power and many volunteers who made this possible. Continued thanks to the repeater committee that keeps the system in good repair. The 145.330 as backup power and a better enclosure that should reduce the likelihood that it will be knocked off the air due to a power outage. A low power mobile should be useful at all parts of the county. HT’s are now more useful should be limited in your choice of mobile rigs.
• A back-up antenna. A low-hanging tree branch might snag your normal antenna. A ¼-wave mag-mount carried in the trunk would make a good substitute.
• Your pad of paper should be accompanied by a lead pencil. If you step out of the car, your pad may get wet. A ball-point pen won’t write very well on damp paper and the ink from a felt-tip or roller-ball pen will likely run if it gets wet.
At all times, consider your personal safety first. If you feel you must take shelter or close your station, do so at your discretion. Be sure to let the Net Control know before you sign off. And if you need assistance at your location, we are here to help.
What frequencies do we use?
The assigned frequencies for Hancock County Severe Weather nets are, in order of preference: 145.330 MHz repeater (-600kHz), 145.330 MHz simplex. or your information, the Skywarn nets in the surrounding counties are on Marion – 146.760-, Shelby County 145.500 simplex, Johnson County 146.835-, Madison County 146.820-, Henry County 147.360, Hamilton County 147.390.

How do we call up a net?
Historically, one of our biggest problems in past years is getting organized in time to provide effective spotting for the NWS. This is a particularly bad problem during weekdays when most local amateurs are at work. We encourage all to participate in the nets whenever possible. If you don’t feel confident, you can practice by volunteering to help with the normal HARC Tuesday night net. One of the reasons the net is held is to practice net procedures. You can’t mess up the Tuesday night net! Just listen to me and/or Rollie………..
To alleviate this problem, we will continue to use a three-tiered net structure which sets forth some, hopefully, clear rules by which we can operate. In the following chart, “When” spells out the conditions we will use to move from level to level. These conditions are triggered by severe weather alerts from NWS or actual conditions in the county. This is a two-way street. If a Tornado Warning is issued which upgrades the net to Red status, when the warning expires or is canceled, the net will automatically revert to Yellow or Green status depending on conditions. “Who” defines the people who have the responsibility to take control of the net under the various levels. “What” explains the kinds of traffic and activities the net will support at each level.

Status When Who What
Green A Severe Thunderstorm Watch or Tornado Watch has been issued by NWS for Hancock, Marion, Shelby, Madison, Any amateur radio operator who copies the issuance of the watch. Preferably, a Hancock County Skywarn Net Control operator will take control of the net, but anyone may act as net control if an assigned NC is not available. The frequency shall remain open for normal use, though stations should keep transmis¬sions short so that the net may be quickly upgraded if re¬quired. Stations should start preparing to observe and report on the weather conditions from their fixed location or prepare to go mobile.
Yellow A Severe Thunderstorm Warn¬ing has been issued by NWS for Hancock County or the NWS specifically directs us to open a formal net, either directly or through the Central Indiana Net. • A Hancock County Skywarn Net Control operator at the direction of NWS or EMA.
• Any amateur radio operator if an assigned Net Control is not available. Formal net status. All traffic shall be directed through Net Control and non-weather-related traffic should be kept to a minimum. Mobile spotters should be dispatched.
Red • A Tornado Warning has been issued by NWS for Hancock County.
• A Skywarn weather spotter or a law enforcement agency has spotted a funnel cloud or tornado in Hancock County. • Net Control
• EMA Only traffic related to a sight¬ing or the NWS’s area of immediate interest may be handled. All other traffic is to standby.
How is severe weather traffic passed?
During a net operation, our Net Control Operator and our Central Indiana Skywarn Net Liaison report to the Central Indiana Skywarn Net, usually conducted on the 146.970MHz (-600kHz) repeater in Indianapolis. Alternatively, the state net can be contacted on 442.650+MHZ. This can be useful for a liaison that has a dual band radio. The Central Indiana Net passes information to us from the NWS and we pass reports to the NWS through the Central Indiana Net. The reason for this is very simple. The folks at the NWS office are usually very busy during a severe weather event. By having one point of contact with the amateur radio spotters, through the Central Indiana Net, the number of people the forecasters have to deal with is considerably reduced. Additionally, the Central Indiana Net acts as a filter and buffer between the spotters in the field and the NWS. While a thunderstorm in Hancock County may be very important to us, the NWS may be dealing with a tornado on the ground in another county. The Central Indiana Net prioritizes the information and makes sure the NWS gets just the information they need at the time. If the Central Indiana Net is not active, but we are active in Hancock County and we have information to pass along, the Net Control or Net Liaison can call the report into NWS by telephone (317-856-0359). In either case, our Net Control will dispatch spotters per NWS request or our best assessment of the situation at hand.
What does the NWS want from us?
Before we go on, let’s talk a bit about the basics. The weather service wants accurate and timely reports of:
• Tornadoes – rotating funnel clouds or wall clouds
• Hail – any size (as modified in 2002 by the NWS)
• Wind – damaging winds of 50 mph or greater or signs of wind damage
• Rain – at a rate of 1" per hour or greater or flash flooding
To be blunt, if it’s not on this list or the weather service doesn’t specifically ask for it, reporting it only ties up the net and distracts everyone from the task at hand. When in doubt, though, ask your net control.
Net discipline
• Please check into the net when the Net Control asks for check-ins and/or you are ready to participate in the net.
• If you check into the net, and then find that you must leave the net for any reason, please advise the Net Control. Spotting tornadoes in the field can be serious and life-threatening business. If you are in danger, consider your personal safety first. Just let Net Control know what the situation is because if you simply disappear from the net, we will feel compelled to send someone out to see what’s happened to you. Additionally, we recognize that some of you have other duties with law enforcement or fire/rescue in the county. Responding to those duties takes priority over weather spotting. Just let Net Control know that you have to leave the net.
• The Net Control may ask you to perform a certain task or report to a particular area. Their requests are based on directions they receive from the Central Indiana Net, NWS, or other authorities, their assessment of the situation, and their knowledge of the county. If you feel that you cannot fulfill the assignment, just ask for another assignment or excuse yourself from the net.
• Keep chatter to a minimum. Make sure your reports are concise. Think about what you are going to say before you key the microphone. Remember the “4 W’s” that reporters use: What, When, Where, Who.
• Don’t panic! If you feel like things are getting out of control, take a deep breath and evaluate the situation. Put the greatest emphasis on the most important tasks, but don’t neglect the rest of the picture.
• Information gleaned from scanners, radar, satellite imagery, etc., is of secondary importance during net activities. No Spotter shall report anything other than personally observed events. Net Control Stations shall request and accept radar and instrument interpretations from the NWS.
• FCC regulations shall be adhered to in all instances regarding station ID, Control Operators, etc. FCC regulations shall supersede any policy or procedure of the program should a conflict ever arise. Individuals are themselves responsible for operating their stations in a lawful manner. Net participants shall ID their stations with their full callsigns at the end of transmissions or at least every 10 minutes during a series of transmissions.
• Plain language shall be used during the nets at all times. Q signals, 10 codes, various prowords, or jargon are to be avoided as much as possible.
• At all times, conduct yourself in a professional and adult manner. Many people, including law enforcement, emergency management, news media, and the public at large, listen to our nets. Our nets go a long way to promoting good will between amateur radio and the county.

Net procedure
• The Net Control will activate the net with the following preamble:
CQ Net, CQ Net, CQ Net. This is a Hancock County Severe Weather Net. On behalf of the National Weather Service at Indianapolis, we are initiating weather spotting activities in Hancock County due to the possibility of severe weather entering the area. Your net control station is [callsign] and my name is [first name]. The net status is [net status]. Please check-in with your callsign, status (mobile or fixed), and location.
A. The net will now stand by for any priority traffic. Please call [callsign], Net Control.
B. The net will now take mobile check-ins, please call [callsign].
C. The net will now take all other check-ins, please call [callsign].
• Upon logging all of the initial check-ins, the NCS will need a Liaison Station. Please ask for someone to volunteer. If there are none, proceed through the roster of base check-ins and ask each individual. NCS shall make sure the Liaison Station is kept current on all net activities. The Liaison Station shall establish and maintain contact with the Central Indiana Net, if operating.
• The Liaison Station shall act, also, as a back-up Net Control. Should NCS not respond within a reasonable time or find it necessary to leave the Net, the Liaison Station shall assume the role of NCS. If this situation continues for more than a brief period, the new NCS (former Liaison Station) shall ask for a new Liaison Station.
• At this point, the Net is “up” and fully functional.
• Should NCS be unsure of the situation at this point, have Liaison check with Central Indiana Net regarding any areas of particular concern. Deploy spotters per the Spotter Preplan or as the individual situation dictates.
• If the Central Indiana Net asks us about a weather system they think is moving into our area, try to get specific details from them about the system’s size, direction, and speed. Our Liaison Station may have to be persistent with the Central Indiana Net in order to get as much information as possible.
• NCS should log the following: time of Net, check-ins, severe weather events in the county and traffic passed to the Central Indiana Net. After the net, please provide me with a copy of this log by mail, fax, or email.
• Pass only the following spotter reports: winds greater than 50 mph, hail , flooding, funnel clouds, wall clouds, tornadoes, rain falling at 1" per hour or greater, significant storm damage, and any other information as requested by the NWS. When taking a Spotter report, you will need: the callsign of the Spotter, the time and location of event, the type of event and any possible descriptive data, such as hail size, etc. Determine if the reported data is measured or estimated.
• NCS should maintain control of the frequency and net operation according to the status of the net. Encourage participants to not engage in unnecessary “chatter”...someone may need the frequency to report something important, maybe even life-threatening! Remember, when in a formal net status, all traffic should be directed through Net Control.
• Pay particular attention to mobile spotters. Keep track of their location and check with them frequently to make sure they are OK. Remember that they are trying to drive and spot weather at the same time...usually at the worst time–during storms! If one does not respond, send someone to check on him/her, call their house, and keep checking until you are certain of their welfare.
• At least every 10 minutes, identify the net as follows: This is [callsign], Net Control for the Hancock County Severe Weather Net. The net status is [net status].
• If the net status changes, identify the net and stress the new status.
• At the close of the net, identify and indicate that the net is closing. Make sure to thank everyone for their participation in the net.

Mobile spotter preplan
The Spotter preplan is suggested for use by Hancock County Severe Weather Net participants in order to maximize the personal safety of individual mobile Spotters and maximize the effectiveness of individual mobile Spotters.
When a person is driving a vehicle during severe weather and observing weather events, his/her attention is divided. This presents an unnecessary hazard to the Spotter and general public, as driving becomes more difficult and hazardous. To make the situation worse, the Spotter is expected to give more than average attention to things other than driving. A fixed location Spotter is more able to give most of his/her attention to observing weather events. Since events can occur at any location within the County, however, mobility is a necessity.
The result is a system of pre-planned locations in which mobile spotters can position themselves to observe events. While the advantage of mobility is retained, the Spotter is able to “fix” him/herself, for a period, and give full attention to observing.
The Net Control Station shall advise Spotters of the area(s) of concern and suggest good locations for observation. The mobile Spotter should deploy to the area and position him/herself in a location affording good observation. The preplanned locations offer good visibility and multiple escape directions should the situation escalate beyond comfort. The Spotter should determine the best location for observation and advise the NCS of his/her position.

Number Location
1 1-70 and SR 9 (In the business parking lot that affords best view of current weather
2 300 S and SR 9
3 SR 9 and 234 (Fire Station parking lot)
4 Southwest of Fortville on 35 with view to SW
5 SR9 and 52 (Parking lot on NE corner)
6 600 W (Mt Comfort Rd) and 52 (Strip mall lot)
7 600 W (Mt Comfort Rd) and I-70 (96 Mile Marker) Gas Station lot NW corner
8 McCordsville at 234 and 35 (Any area with clear view to incoming weather)
9 US 400 and 500 W (Hoosier Poet motel)
10 Sugar Creek Fire Station (US 40 and 300 W)
11 Shirley (109 and 234)
12 Mount Vernon High School

Always keep your personal safety and the safety of others in mind. Park as far off the road as possible so as to not block traffic. Turn on your parking lights and/or four-way flashers so others can see you. Be aware of your surroundings, especially possible flying debris or rapidly rising water in ditches.

Handy references

The following section lists terms and definitions associated with supercell thunderstorms. The terms and definitions are from NOAA Technical Memorandum NWS SR-145, A Comprehensive Glossary of Weather Terms for Storm Spotters (available on the web at
Rain-free base: A dark, horizontal cloud base with no visible precipitation beneath it. It typically marks the location of the thunderstorm updraft. Tornadoes may develop from wall clouds attached to the rain-free base, or from the rain-free base itself - especially when the rain-free base is on the south or southwest side of the main precipitation area. Note that the rain-free base may not actually be rain free; hail or large rain drops may be falling. For this reason, updraft base is more accurate.
Downburst: A strong downdraft resulting in an outward burst of damaging winds on or near the ground. Downburst winds can produce damage similar to a strong tornado. Although usually associated with thunderstorms, downbursts can occur with showers too weak to produce thunder.
Wall cloud: A wall cloud, according to the storm spotters glossary, is a local, often abrupt lowering from a rain-free base. Wall clouds can range from a fraction of a mile up to nearly five miles in diameter, and normally are found on the south or southwest (inflow) side of the thunderstorm. When seen from within several miles, many wall clouds exhibit rapid upward motion and cyclonic rotation. Rotating wall clouds usually develop before strong or violent tornadoes, by anywhere from a few minutes up to nearly an hour. Wall clouds should be monitored visually for signs of persistent, sustained rotation.
Tornado: A violently rotating column of air in contact with the ground. A condensation funnel does not need to reach to the ground for a tornado to be present; a debris cloud beneath a thunderstorm is all that is needed to confirm the presence of a tornado, even in the total absence of a condensation funnel. A description of tornado intensity classification is shown below.
LP storm (or LP supercell): Low-Precipitation storm (or Low-Precipitation supercell). A supercell thunderstorm characterized by a relative lack of visible precipitation. Visually similar to a classic supercell, except without the heavy precipitation core. LP storms often exhibit a striking visual appearance; the main tower often is bell-shaped, with a corkscrew appearance suggesting rotation. They are capable of producing tornadoes and very large hail. Radar identification often is difficult, so visual reports are very important. LP storms almost always occur on or near the dry line, and therefore are sometimes referred to as dry line storms.
HP storm or HP supercell: High-Precipitation storm (or High-Precipitation supercell). A supercell thunderstorm in which heavy precipitation (often including hail) falls on the trailing side of the mesocyclone. Precipitation often totally envelops the region of rotation, making visual identification of any embedded tornadoes very difficult and very dangerous. Unlike most classic supercells, the region of rotation in many HP storms develops in the front-flank region of the storm (i.e. usually in the eastern portion). HP storms often produce extreme and prolonged downburst events, serious flash flooding, and very large damaging hail events. Mobile storm spotters are strongly advised to maintain a safe distance from any storm that has been identified as an HP storm; close observations (e.g., core punching) can be extremely dangerous.

Estimating Hail Size
pea size 1/4”
marble size 1/2”
penny size 3/4”
quarter size 1”
golf ball size 1 3/4”
baseball size 2 3/4”
Estimating Wind Speeds *(miles per hour)
25-31 Large branches in motion; whistling heard in telephone wires
32-38 Whole trees in motion; inconvenience felt walking against wind
39-54 Twigs break off trees; wind generally impedes progress while walking
55-72 Damage to chimneys and TV antenna; pushes over shallow rooted trees
73-112 Peels surface off roofs; windows broken; light trailer houses pushed or overturned; moving automobiles pushed off roads
113-157 Roofs torn off houses; weak buildings and trailer houses destroyed; large trees snapped and uprooted
158 & up Severe damage; cars lifted off ground
*Adapted from the Beaufort and Fujita Wind Scales.
Tornado Intensity – Fujita Scale
F-Scale Winds Character of Damage Relative Freq.
F0 (weak) 40-72 mph light damage 29%
F1 (weak) 73-112 mph moderate damage 40%
F2 (strong) 113-157 mph considerable damage 24%
F3 (strong) 158-206 mph severe damage 6%
F4 (violent) 207-260 mph devastating damage 2%
F5 (violent) 261-318 mph incredible damage < 1%

Web Resources
Hancock Amateur Radio Club –
Central Indiana Skywarn –
Indianapolis National Weather Service Forecast Office –
NOAA/NWS Storm Prediction Center –
Stormwarn – a system which delivers weather bulletins to your email or pager –