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Last Updated: 12/2/09 
U.S. Tornado Droughts
Greg Carbin, the Storm Predication Center Warning Coordination Meteorologist, posted an interesting article to the U.S. Severe Weather Blog recently. Check it out at:
Incidentally, the Storm Prediction Center (SPC) issued no Tornado or Severe Thunderstorm Watches during November 2009. This is the only November in the watch database (since 1970) when no watches have been issued during the month.
2009 SKYWARN Recognition Day - December 5
Our annual SKYWARN Recognition Day is scheduled for this Saturday, December 5, 2009. Volunteer amateur radio operators from the La Crosse area will participate by making contacts with other operators and NWS offices around the country. Here are links to our SKYWARN Recognition Day activities: (NOTE: The event was cancelled locally in 2007 because of a winter storm.)
- 2008 SKYWARN Recognition Day
- 2006 SKYWARN Recognition Day
- 2005 SKYWARN Recognition Day
- 2004 SKYWARN Recognition Day
- 2003 SKYWARN Recognition Day
- 2002 SKYWARN Recognition Day
- 2001 SKYWARN Recognition Day
- 2000 SKYWARN Recognition Day
2009 Had Its Share of Severe Weather
An abnormally cool summer led to a fairly quiet severe weather season across the region. NWS Green Bay had no severe weather in June or July 2009 and only 10 severe weather reports all year. The La Crosse NWS ended up issuing 117 warnings total, but only above normal warnings during April and July.
Even though things were pretty quiet, we still had a significant tornado hit the Austin, MN area in June, several significant hail storms in July, and a day in August where 4 small tornadoes hit parts of northeast Iowa. Large hail impacted crops in Iowa and led to losses in the $ millions.
Here are the number of warnings issued by month and county for 2009...
| 2 | |
| 15 | |
| 8 | |
The La Crosse NWS greatly appreciates all the efforts by spotter groups and Emergency Management personnel to assist in the severe weather watch and warning process.
Spotter Situational Awareness
An important concept we have been focusing on in our training sessions each spring is for spotters to be self aware of the weather threats each day (if any) and take advantage of guidance that is available from the National Weather Service.
For example - -
- Do you know if we are under a risk of severe weather?
- What about in the next 3 days?
- Is spotter activation recommended for your county?
- Were any warnings issued for your area in the past 24 hours?
Do you know the answers to these every day?
Use these tools to stay ahead of the severe weather threat...
- Outlooks
Convective Outlooks are graphical forecasts that can give "heads up" on a severe weather potential in the upper Midwest several days in advance. They can easily be viewed on our Outlooks web page or via the Storm Prediction Center's web site. There are three levels of risk in the outlooks - Slight (SLGT), Moderate (MDT), and High (HIGH).
Hazardous Weather Outlooks (HWO) are issued locally between 5-6 a.m. and updated as needed with details on any expected weather hazards over the next seven (7) days, including information about a possible need for storm spotters, Emergency Management conference calls, and timing. These usually mirror the convective outlook graphics mentioned in the previous paragraph and but give more local details and forecasts from our office.
They can be viewed on our web site, heard on NOAA Weather Radio (around the top and bottom of each hour (H+00 / H+30), or Emailed to spotters.
- Spotter Activation Notification System (SANS)
The La Crosse NWS office also recommends county storm spotter activation (and deactivation). You can hear these activations over weather radio, receive Emails or text messages via your cell phone, or watch for activations on our public activation page - www.weather.gov/lacrosse/activation
- Hazardous Weather Information Search
A new Hazardous Weather Informatoin Search (HWIS) tool has been developed by NWS La Crosse to easily review what informational products were issued for a particular county over the past 3 days. This can be used to review information that was sent from the La Crosse NWS office and aid in post storm analysis.
This new page can be found at: www.weather.gov/lacrosse/emNotify
Natural Hazard Assessments Available
NWS La Crosse has completed Natural Hazard Assessments for every county in our service area. These assessments examine hazardous weather history and potential, including tornadoes, flooding, severe winter weather, and heat, among other topics.
Each assessment is about 12 pages and in PDF format making it easy to print or use. You can browse for your county at:
If you have any comments or questions about these new assessments, contact Warning Coordination Meteorologist - Todd Shea, via Email at: todd.shea@noaa.gov. This project was started in October 2008 and completed in June 2009. Each assessment will be updated yearly based on any new information and with the latest watch and warning statistics.
2010 SKYWARN Spotter Training Being Scheduled
Spotter training classes for the 2009 season were completed in April 2009. We held 26 public training sessions in 23 counties with an estimated attendance of 1749, up 106 from 2008 training.
Classes for the 2010 season (March and April 2010) have started to be scheduled. Our schedule and attendanace can be viewed at:
If you have questions about the training or would like to schedule a class for 2010, drop Warning Coordination Meteorologist - Todd Shea, an email at: todd.shea@noaa.gov.
Spotter Activation Notification System (SANS) Becomes Official in 2009
A new Spotter Activation Notification System (or SANS) was developed by NWS La Crosse staff members and tested in the 2008 season. The goal of SANS was to provide guidance to spotters and spotter groups when activation is suggested by the La Crosse National Weather Service. Of course, local activation guidelines always apply and spotter groups should continue to monitor weather forecasts and conditions closely, deploying when strong to severe storms approach their area.
After review from the 2008 season and additional guidance to both NWS La Crosse staff members and spotters in our area, it was decided to keep this new system and enhance the use of it in 2009. It will become official and be used in full this coming season so we hope to sign up many more spotters at our training sessions in March and April 2009.
There were 220 activations recommended by NWS La Crosse in our 28 county service area in 2008. Average lead time to the first warning issued was 16.2 minutes and average lead time to the first severe weather report was 40.5 minutes. Warnings were issued during 150 of the 220 activations. Communication problems, especially with the text message aspect of the service, proved mix results for some areas. We are hoping these problems have been resolved as we move forward this year.
SANS notified spotters using four methods:
- Email to specific contacts
- Text message via cell phone to specific contacts
- Brief message over NOAA Weather Radio
- Update a web page, including a map showing activation status
The web page can be monitored at: www.weather.gov/lacrosse/activation
It will refresh automatically every 5 minutes.
We are currently looking for your feedback on this system, even as we continue to use it in 2009. Drop Warning Coordination Meteorologist - Todd Shea, an email for comments: todd.shea@noaa.gov.
Spotter Reporting and Data Quality
There are many web sites that can aid in storm spotting. Here is a quick 15-minute module online session that deals with spotter reporting and data quality.
The link can be found at:
StormReady Program Update
Spring Valley, MN is our latest community to become StormReady - recognized on May 11, 2009.
Hillsboro, WI became StormReady in September 2008 for showing great effort to boost preparedness and weather safety in their community.
Edgewood, IA and Eyota/Dover, MN recently renewed their StormReady status as well, now valid through 2012! Great!
If you have a community in your area that is very pro-active with weather, coordinates with the National Weather Service actively, and takes preparedness efforts very seriously, consider applying for the StormReady program.
For more information on the StormReady program, check:
Anticipating Hazardous Weather and Community Risk Course Available
A great on-line course is available from FEMA and the Cooperative Program for Operational Meteorology, Education and Training (COMET®) called "Anticipating Hazardous Weather and Community Risk". We recommend every Emergency Management director take this course if time allows, and spotters may also have an interest.
The on-line class can be found at the following link:
Private Schools and Public School District Offices Receiving Weather Radios in 2008/09
NOAA Weather Radios were distributed to public schools across the country over the past few years, as a part of a program designed to help maintain the safety of our schools. These weather radios will help provide information about severe weather alerts, terrorist threats and other local emergencies to the staff and students in our public schools. More details on this program can be found on the NOAA Public Alert Radios for Public Schools web page.
Schools are asked to register their radios, so that the agencies sponsoring the program are assured that the weather radios got to their proper destination. If your public school did not receive a weather radio, the registration page can also be used to provide the information about your school needed to get one shipped out.
Distribution to private schools and school district offices started in the fall of 2008 and continue now. Again, please use the web page listed above to register receipt of your radio.
The radios can be programmed so that only the alerts affecting your immediate area are received. The programming is done based on Specific Area Message Encoding (SAME) codes. Each county has its own SAME code. Instructions for programming the radio were included in the shipment, or can be found online. The National Weather Service provides a list of SAME codes for counties across the entire country.
For more information about NOAA Weather Radio, frequencies, and coverage areas consult the NWS La Crosse Weather Radio web page.
Enhanced Fujita Scale Officially Begins
The National Weather Service began implementing (as of 2/1/07) the Enhanced Fujita (EF) Scale to rate tornadoes in a more consistent and accurate manner. Details concerning the EF Scale can be found at our new EF Scale web page:
www.crh.noaa.gov/arx/efscale.php
Storm Based Warnings - What Changes?
The National Weather Service (NWS) announced recently that offices will begin issuing Storm Based Warnings as of October 1, 2007. In reality, the La Crosse NWS has been issuing warnings in this fashion for several years already.
Instead of just picking whole counties ahead of the storm, we are warning based on a threat area (or polygon) ahead of the storm. If that threat area touches a section of the county, it is listed in the actual written warning.
The threat area, or polygon that is created by the radar-warning meteorologist, is viewable on NWS radar imagery. The text in the actual warnings usually will detail sections of a county under the threat depending on how much of that county is actually covered.
So, NWS warnings will still be issued. They will still list counties or sections of counties under a severe weather threat. In addition, they will be a bit more detailed and centered on the main threat area. This also means you could have two warnings out for the same county because they are "storm based" and not county based. You could have a threat area in the northern half of the county and a second in the extreme southeast part. Or perhaps a Severe Thunderstorm threat in one part and a tornado threat in the other.
The option to view the warning in a graphical fashion (actually view the threat area or polygon as laid out by the warning meteorologist) is a great advancement - likely the future of warning operations.
Look at the examples (two graphics below) from northeast Iowa in 2006 (left) and western Wisconsin in June 2006 (right). Notice how the threat areas (polygons) only cover small sections of the counties. Far fewer people were actually under a severe weather risk compared with if all these counties were warned in their entirety.
 |
 |
| (click to enlarge) | (click to enlarge) |
On a related note, the NWS will start to verify warnings issued based on reports from within this polygon instead of county based as part of this change.
A full story on Storm Based Warnings can be found by clicking here.
NWS Information Primer for Spotters
A new web page has been created that details information (or products) available from the National Weather Service before, during, and after severe weather.
Check it out at www.weather.gov/lacrosse/spotnwsinfo.php.
Weather Radio Monitors Needed
The La Crosse National Weather Service is looking for people that could monitor NOAA All Hazard Weather Radio for them when a problem develops with the transmitter. We would primarily use them to contact when a known problem develops just to confirm the signal is on or off the air. Of course if you ever hear of a problem with our radios or notice they are off the air, send our office an instant message or call as soon as possible.
The Instant Message Link is at: http://www.crh.noaa.gov/arx/scripts/instant_message_nws_arx.php
If you would like to be a monitor for us, email Warning Coordination Meteorologist (WCM) Todd Shea at todd.shea@noaa.gov.
Spotter Activation Guidelines
Two guideline sheets are available to help spotter groups with activation issues and questions.
There are certainly no right or wrong answers with such a tough subject, but if groups remain pro-active and organized, they can become more self reliant and serve their local communities better. The National Weather Service heavily relies on spotter reports and the efforts these volunteers put towards helping their area.
These new guidelines are in PDF form, and can be downloaded or viewed from the following links:
Remember, in 2009 we will be using our new spotter activation system (see story above). This can be monitored off the following link:
www.weather.gov/lacrosse/activation
Awareness Week Information
National Flood Safety Awareness Week - 2010
Severe Weather Awareness Week - 2010
NOAA All Hazard Radio Awareness Day - 2010
Heat Awareness Day - 2010
National Lightning Safety Awareness Week - 2010
Winter Weather Awareness Day/Week - 2010
Hazardous Weather Outlooks
Feel free to drop a note to Todd Shea at todd.shea@noaa.gov if you want any spotters added to the HWO distribution e-mail system we have. The Green Bay NWS office also provides this service.
- National Weather Service
- La Crosse, WI Weather Forecast Office
- N2788 County Road FA
- LaCrosse, WI 54601
- 608-784-7294
- Page Author: ARX Webmaster
- Web Master's E-mail: w-arx.webmaster@noaa.gov
- Page last modified: December 2nd 2009 7:30 PM