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MORE ABOUT WEATHER ISSUES

 

A few weeks ago, after the first snowfall, I shared information about our process for making winter weather decisions.  We covered a wide variety of situations to give a broad basis on weather issues. 

Over the past week, we have experienced weather focused on cold conditions.  Some questions have come through the District Office about conducting school when it is cold outside.  I would like to share some information about the issues related to cold weather.

 

GENERAL COLD WEATHER

For the most part, we have to understand that we live in Minnesota and we will experience periods of cold weather.  While we may not like or appreciate the conditions, the fact is that we will have times of cold weather.

Compared to the very nice weather we experienced all fall, the recent change to cold was rather abrupt!  We went from above normal temperatures to well-below normal temperatures.  Even though it has been cold and it was an abrupt change, the conditions have not been considered “dangerous.”

Cold weather, in and of itself, is generally not a reason we use to close school.  With all the advances in technology, equipment, and safety, students are relatively safe in moving to and from school. 

We have to assume that parents will appropriately clothe students and we know that the time outside can be limited.  Buses and vehicles have good heating systems.  Once students are at school, we are able to be safe inside the buildings.  There are not prolonged periods where students are exposed to cold weather.

If travel is not affected by other conditions—ice, snow, reduced visibility—the issue of cold does not usually constitute a reason for closing school.

 

COLD WEATHER FACTORS

Contrary to popular belief, there is not a specific wind chill or temperature condition that “automatically” triggers a decision to have or not have school.  There is nothing that specifically defines any one element “making” our decision.

The National Weather Service wind chill chart is an excellent resource when extreme cold becomes a part of the situation.  The chart considers both the actual temperature as well as the impact of wind in setting the “feels like” temperature.

The wind chill chart has a “boundary” line where the frostbite time moves from 30 minutes to 10 minutes.  Again, this shows the frostbite zone when you consider actual temperature as well as the combination of temperature and wind.

The challenge with this is that the temperature and wind interact so that the boundary “moves”.  Thirty below, with no wind, is still within the 30 minute window.  Thirty below, however, with a 10 mph wind is clearly in the 10 minute frostbite window. 

 

DECISION GUIDELINES

As area superintendents have talked about these extreme conditions, we have generally agreed that the 10 minute frostbite zone would be a point at which school is likely to be closed.  Normally, cold temperatures by themselves do not get into the 10 minute frostbite zone.

Temperatures, then, can get into the minus 20 range—if there is not wind—without hitting the 10 minute frostbite zone.  So, if we consider temperatures, alone, it has to get very, very cold to close simply based on temperatures.

More often, it is the combination of temperature and wind that factor into the weather decisions.  When the temperature and wind combine to give extreme conditions, there is concern about student safety.  The 10 minute zone is a standard that many school leaders in the area agree would be used to close school.

 

FINAL THOUGHTS

As with general conditions, there are no formal guidelines in place to determine when to conduct or cancel school—especially if we consider cold conditions only.  Each decision is made independently based on the conditions that exist and are forecast at the time of the decision.

Although weather forecasting is based on scientific principles, there is no guarantee that forecasts or projections will be completely accurate.  Weather conditions can also be very different in locations just a few miles apart.  The air temperature, amounts of precipitation (in whatever form it takes), wind speed, wind direction, length of expected conditions, timing of weather changes, severity of conditions, previous conditions, and many other issues complicate the process of weather decisions.

As a school district, it is more likely that we would close school because of a combination of conditions rather than simply temperature or cold conditions.

For the most part, we have to understand that we live in Minnesota and we will experience periods of cold weather.  While we may not like or appreciate the conditions, the fact is that we will have times of cold weather.

Compared to the very nice weather we experienced all fall, the recent change to cold was rather abrupt!  We went from above normal temperatures to well-below normal temperatures.  Even though it has been cold and it was an abrupt change, the conditions have not been considered “dangerous.”

Cold weather, in and of itself, is generally not a reason we use to close school.  With all the advances in technology, equipment, and safety, students are relatively safe in moving to and from school. 

We have to assume that parents will appropriately clothe students and we know that the time outside can be limited.  Buses and vehicles have good heating systems.  Once students are at school, we are able to be safe inside the buildings.  There are not prolonged periods where students are exposed to cold weather.

If travel is not affected by other conditions—ice, snow, reduced visibility—the issue of cold does not usually constitute a reason for closing school.

 

COLD WEATHER FACTORS

Contrary to popular belief, there is not a specific wind chill or temperature condition that “automatically” triggers a decision to have or not have school.  There is nothing that specifically defines any one element “making” our decision.

The National Weather Service wind chill chart is an excellent resource when extreme cold becomes a part of the situation.  The chart considers both the actual temperature as well as the impact of wind in setting the “feels like” temperature.

The wind chill chart has a “boundary” line where the frostbite time moves from 30 minutes to 10 minutes.  Again, this shows the frostbite zone when you consider actual temperature as well as the combination of temperature and wind.

The challenge with this is that the temperature and wind interact so that the boundary “moves”.  Thirty below, with no wind, is still within the 30 minute window.  Thirty below, however, with a 10 mph wind is clearly in the 10 minute frostbite window. 

 

DECISION GUIDELINES

As area superintendents have talked about these extreme conditions, we have generally agreed that the 10 minute frostbite zone would be a point at which school is likely to be closed.  Normally, cold temperatures by themselves do not get into the 10 minute frostbite zone.

Temperatures, then, can get into the minus 20 range—if there is not wind—without hitting the 10 minute frostbite zone.  So, if we consider temperatures, alone, it has to get very, very cold to close simply based on temperatures.

More often, it is the combination of temperature and wind that factor into the weather decisions.  When the temperature and wind combine to give extreme conditions, there is concern about student safety.  The 10 minute zone is a standard that many school leaders in the area agree would be used to close school.

 

FINAL THOUGHTS

As with general conditions, there are no formal guidelines in place to determine when to conduct or cancel school—especially if we consider cold conditions only.  Each decision is made independently based on the conditions that exist and are forecast at the time of the decision.

Although weather forecasting is based on scientific principles, there is no guarantee that forecasts or projections will be completely accurate.  Weather conditions can also be very different in locations just a few miles apart.  The air temperature, amounts of precipitation (in whatever form it takes), wind speed, wind direction, length of expected conditions, timing of weather changes, severity of conditions, previous conditions, and many other issues complicate the process of weather decisions.

As a school district, it is more likely that we would close school because of a combination of conditions rather than simply temperature or cold conditions.