North
East Indiana
District 2
S K Y W A R N
The Northeast
Indiana/Northwest Ohio Storm Spotter Program
by Joel Tye, KB9RH
2009 was one of the quietest years on record for severe weather, but with the new year it is again time for storm spotters to get prepared for the upcoming season. The National Weather Service has scheduled basic storm spotter training sessions where meteorologists review severe thunderstorms and bring spotters up to date on the latest research. This year’s session is scheduled for March 16 at the Public Safety Training Academy. If you cannot attend the training for Allen County, the dates for other sessions can be found at the NWS North Webster homepage www.weather.gov/iwx
Even though significant advances have been made in radar technology, meteorologists cannot see what is happening at the surface because of the curvature of the earth. Therefore, our “ground truth” reports supplement what is being seen on radar.
According to statistics, the primary severe weather season in our area runs from
May 4 through August 29th. But as we all know, severe weather can occur in any
month of the year and at any time of day. The primary threat here is
straight-line winds - and by a wide margin.Most of the severe weather in our
area is the result of squall lines of thunderstorms. The classic “supercell”
thunderstorms are rare in this part of the country - but they occasionally do
happen.
The two most important aspects of storm spotting are safety and accurate
reporting. For those reasons, it is best to be “situationally aware” of
atmospheric conditions. One of the best sites on the internet is the Storm
Prediction Center at www.spc. noaa.gov. The daily convective outlooks and
mesoscale discussions detail the specific types of severe weather expected.
An overview of the Indiana/Michigan/Ohio spotter program: If a tornado or severe thunderstorm watch is issued by the Storm Prediction Center, the staff at the North Webster National Weather Service office will evaluate the situation and determine when and if spotters are needed. Even if there is a watch in effect and no severe weather in our area, we may initiate a “standby” net. Under certain atmospheric conditions, severe weather may develop very rapidly and we need to be ready. An operator may be called in to staff the amateur station at the Weather Service office. That station operates under the callsign WX9IWX.
When we are activated, the net itself operates on the 146.88 repeater (146.76
backup) as a directed net. By definition, a directed net is a radio net in which
no station (other than net control) may communicate with any other station in
the net without first obtaining permission from net control. The net controls
are responsible for managing traffic on the net. Please follow their
instructions.
The reports of certain specific weather conditions called in by trained spotters
are directed to meteorologists who compare the information to other reports and
to radar images. The office is responsible for issuing forecasts and warnings
for 37 counties in northern Indiana, northwest Ohio, and the border counties in
Michigan. For amateur radio spotting purposes, these counties are divided into
four quadrants; we are southeast or Quad 2. There are 10 other counties in the
quad, so reports will also be coming in from liason stations to those county
nets.
As the storms approach and move through our area, net control or his designated
station will attempt to give updated radar information to spotters in the field.
We may also get radar updates and special weather statements from the amateur
operator at the WX9IWX station. Every effort is made to insure spotters have the
latest information, but that is not always possible.
Here are the specific weather conditions the National Weather Service would like
to have reported:
1.
Tornadoes, Funnel Clouds, and Wall
Clouds (remember there must be rotation).
2. Winds 45 miles per hour or greater (please note if winds are estimated or measured).
3. Any Hail (NWS requests we do not report “marble size” hail). Please report hail size as pea-size, dime, nickel, quarter, etc. Even better, measure it with a ruler.
4. Heavy Rain (1 inch or more in 1 hour or less, or storm totals of 2 inches or more).
5. Flooding in progress (rapid pooling of water on roadways, etc).
6. Storm damage (large trees, branches, any structural damage, etc).
Keep your reports short and to the point. Your report should take 10 or 15
seconds at the most. If the storms are especially severe, there may be a flurry
of reports in a short amount of time; this happens often. Depending on the
situation, net control may ask spotters to hold lower-priority reports for a few
minutes (if there is a tornado on the ground, that situation takes priority over
pea-size hail!).
Please report only what you see. Don’t speculate. If you see power flashes in
the distance, do not call it in as a tornado unless you actually see the funnel.
Report only the power flashes.
If you believe you have a reportable condition, but are not sure, report your
suspicions to the net. An example would be if you are observing low-hanging
clouds underneath the rain-free base, but are too far away to tell if there is
rotation. There may be other spotters in the area, and your report can be
checked out on radar.
There are times when severe weather occurs even though there is no official
weather watch in effect and a net has not been called. If you have something to
report, please give your call sign and indicate that you have a severe weather
report. Any station with access to a telephone can call in your report to the
North Webster office.
Space limitations do not permit a complete discussion of all situations which
may occur during a severe weather net. Just remember to use common sense when a
net is activated and always put safety first - we want you to be here for the
next severe weather event. Be sure to operate from a location where you can
safely observe the sky, and always have an escape plan if the unexpected should
happen.
One last reminder: the 2010 Central Indiana Severe Weather Symposium is Saturday
March 13th in Greenwood, Indiana. The theme of this year’s advanced
training is “Hazards, Spotting, Safety”. Speakers include Chris Novy- who was
one of the speakers at the northern Indiana advanced training last year. Another
speaker is Dan McCarthy - Meteorologist in Charge at NWS Indianapolis - who
worked for 20 years as a forecaster at the Storm Prediction Center. For more
information and registration information please go to the NWS Indianapolis
website at www.weather.gov/ind.
from Joel KB9RH
You can also download a PDF version of this letter by clicking here.