What is the difference between relative humidity and dewpoint?

Both relative humidity and dewpoint measure moisture but they do it in different ways.  Relative humidity tells you how much moisture is in the air compared to how much the air can hold (warmer air holds more moisture than colder air).  Dewpoint tells you exactly how much moisture is in the air. It’s not measured in inches, feet or gallons, it’s simply a number.  Dewpoint is also the temperature that you can cool air down to in order to get dew or condensation.  Relative humidity is moisture measured relative to the air temperature, dewpoint is not. 

What is pressure?

Pressure is a measurement of how much air there is above us in the atmosphere.  Normally we can not feel the changes in pressure, unless it happens very quickly.  Low pressure or falling pressure generally indicates clouds and wet weather.  High pressure or rising pressure means calm and clear weather.  People with arthritis are very sensitive to changes in pressure. 

What is the wind-chill?

Wind-chill is the condition that we talk about mainly in the winter.  It’s how cold the wind makes us feel.  When the wind is blowing and temperatures are below zero, we combine those two numbers to come up with the wind-chill factor.  In order to stay safe when the wind-chill is well below zero, wear several layers of clothes to help your skin retain heat.  Wind-chill only applies to human skin, not inanimate objects.  

What is the heat index?

Heat index is the condition we talk about mainly in the summer.  It’s what the air temperature “feels like” to us.  Heat index combines the air temperature and the amount of moisture present in the air.  Our bodies natural way to cool off is by perspiration.  On a warm day with low humidity, the perspiration on our skin evaporates, cooling us off, but when the humidity is high, less evaporation takes place, so our bodies do not cool off. 

What is virga?

Occasionally, the rain falling from the clouds never reaches the ground, this we call virga.  If the air is too dry near the surface, this rain falling will evaporate before it hits the ground.

What does zonal mean?

This a region where the winds flow from a west to east direction.

Is it ever too cold to snow?

No.  When the air is very cold, the dewpoint is low meaning it holds little moisture but even a little moisture can make a cloud to produce a little snow. 

What is the jet stream?

The jet stream is a narrow band of strong winds concentrated high above the earth’s surface.  The jet stream guides our weather systems around the globe.  It is possible to have more than one jet stream above a continent.  

How do I set my barometer?

There should be a dial on the back or bottom of the barometer that adjusts the current readings.  Simply turn the dial until the reading is the same as the current pressure.  As the pressure changes throughout the day you’ll see the needle or mercury move.  Some barometers have a second dial that does not move unless you move it.  It’s there for a reference so you can see the pressure change from day to day. 

What is a  Nexrad Doppler Radar?

KWQC-TV6 Nexrad Doppler Radar is state-of-the-art technology which allows the First Alert Weather Team to accurately predict where areas of hail, damaging winds or tornadoes are likely to occur.  Nexrad Doppler is so powerful it can pinpoint developing severe storms and tornadoes up to 20 minutes before they strike. 

What is a satellite?

A satellite is a camera that takes pictures of the earth from about 22,000 miles above the surface.  The satellite shows clouds.  

How do I convert from Fahrenheit to Celsius?

The easiest way to do this mathematical equation is to start at zero degrees Celsius and 32 degrees Fahrenheit.  Now for every 10 degrees Celsius add 18 degrees Fahrenheit.  For example:  20 degrees Celsius equals 68 degrees Fahrenheit.

Or use the formula: C=5/9*(F-32) or F=(9/5*C)-32 

Where do I get past weather information?

The National Climatic Data Center in Asheville, North Carolina archives all weather data for the entire United States.  For local weather information, one of the easiest ways to find this information is to go to the library and look in the weather section of a newspaper.  Most major papers have a weather map along with a summary of the previous day’s weather. 

Why does the forecast change everyday?

Weather is always changing, and since we get new models twice a day we can sometimes see something that we did not see on the early model run.  We normally update the forecast twice a day to make sure we have the most accurate and dependable forecast out there. 

Where does your weather information come from?

We receive our data from The National Weather Service in Washington, DC.  The data is compiled and sent to us by satellite.  It includes readings taken at thousands of sites each hour around the world.  We also use satellites and radars which are updated every few minutes. 

How accurate is the 6 Day Planner?

We have models that will show us the forecast at least six days out, so the 6 Day Planner is better than it was a few years ago.  When you look at the Planner, look at the trends not the exact numbers, and look at the 6 Day Planner as an outlook not a forecast. 

Why is Moline used as an “official” temperature?

As far back as the records show, they have been taken at Moline, IL.  Most forecasters use it as a standard so that when you hear different forecasts you’ll know that they all have the same reference. 

Why is the new NWS office in Davenport and not in Moline?

When the NWS was looking to build the new office with a new Nexrad Doppler Radar they looked at the current site at the Quad Cities Airport in Moline, but if you know the geography of the Quad Cities, you know that the airport sit down in a valley.  So the NWS looked to a higher place and found the Mount Joy Airport in northern Davenport as the new site. 

What is the First Alert Skywatcher Network?

Throughout Eastern Iowa and Western Illinois more than 50 KWQC-TV6 Skywatchers work with the First Alert Weather Team to keep you on top of the days weather.  As volunteers, these dedicated individuals report critical changes in the weather as soon as it happens.  As severe weather develops over the First Alert forecast area, our Skywatchers will keep us and you up to date as the storms move through their neighborhoods.  This gives you more warning and a better idea of what might be about to hit your town.  Even when the weather is clear, our First Alert Skywatchers give us local weather reports that give us a more accurate picture of all the weather around Eastern Iowa and Western Illinois. 

Is it true that there really is no map behind the weathercaster?

Yes!  When we deliver the forecast we stand in front of a blank green wall.  The maps you see behind us are actually electronically inserted over the color green.  We know what is “behind” us only by looking at TV monitors off to the side of the wall.  

What do the letters “AMS” and “NWA” mean next to the weathercaster’s name?

AMS is the American Meteorological Society and NWA is the National Weather Association.  The letters mean the weathercaster earned a certification from either organization stating that his or her weathercasts meet a certain level of skill in communication and presentation. 

Do any of the weathercasters tape their forecasts?

No.  The news and weather segments are always live.  In fact, the entire weather segment is not even scripted.

Can I get one of the First Alert Weather Team to come out to my community?

We get dozens of requests for appearances each week.  Depending on our on-air schedules, normally one of the First Alert Weathercasters would be able to attend a community event to talk about weather.  You can call the station or send a letter to the weathercaster that you would like to see.  Keep in mind that are schedules full up quickly, so send your request as soon as you can.  We will try our best to fulfill a request. 

Are there tours available of the First Alert Weather Center?

KWQC-TV6 does offer tours of the station for educational purposes.  Included in this tour is a tour of the First Alert Weather Center. 

How do I get a weather question answered on the air?

Every Wednesday on the KWQC-TV6 News at 5, Meteorologist Erik Maitland answers viewer questions in a segment called “Weatherwise”.  If you have a weather question that you would like answered, send it to Erik Maitland at the station or e-mail it to TVWEATHERGUY@yahoo.com.  

What is a cold air funnel?

A cold air funnel resembles a small tornado except that it is usually very weak.  They form on days when there is a lot of cool air above the ground, especially in the fall. 

What is a Weather Radio?

It’s a radio that picks up a continuous broadcast from the National Weather Service, 24 hours a day, around the United States.  They are inexpensive and sold at most electronics stores.  Many are portable and battery-operated, and contain a built-in alarm that sounds when severe weather is possible. 

What is severe weather?

Severe weather is a sudden, violent, hazardous weather that comes from powerful thunderstorms.  It could be large hail, flash flooding, extreme winds or tornadoes. 

When does severe weather happen?

Severe weather is most likely in the warm months of the year, and mainly from early spring through fall.  This is when the temperature and humidity levels are high and a strong jet stream is above us.  Severe storms can happen at any time, day or night, but are most likely in the late afternoon. 

What is the difference between a watch and a warning?

A watch is issued when conditions are favorable for severe weather to develop.  This is the time to prepare for the possibility of dangerous weather.  A warning is issued when severe weather is spotted or is indicated by radar.  This is the time to take action. 

Is there always a warning before severe weather?

No, because sometimes it develops before we can detect it.  In the majority of the cases, however, a watch is issued first and then a warning before severe weather happens. 

What are the tornado safety rules?

Get in the center of the basement or lowest level of the house.  You want to put as many walls between you and the outside as possible.  Closets and bathrooms offer the best protection because of their structural integrity.  Cover yourself with blankets and pillows but not mattresses.  Get under a sturdy work bench if you can.  Do not open windows-you must stay away from glass.  If you live in a mobile home, get to a designated shelter immediately.  Do not stay in the trailer!  If you are in your car, stop and get into a ditch or culvert, Do not try to outrun a tornado.  If your house is hit, be alert for leaking gas or live power lines.  

What are the lightning safety rules?

Stay well inside the house-away from windows and doors.  Don’t use the phone or other electrical appliances.  Turn off your computer-unplug it if you can.  If on the road, stay in your car.  Get out of swimming pools at the first sign of lightning.  If caught outside, avoid becoming the tallest object around.  Head for a ditch or low point, but be aware of possible flooding.  Give the storm plenty of time to leave your area.  You can still be struck by lightning when a storm is 5 to 10 miles away.  

What are the flash flood safety rules?

When thunderstorms with heavy rain move through, keep an eye on flood-prone streams and ground you live near.  Keep children from playing near ditches and storm drains.  Do not drive on flooded roads.  You don’t know how deep the water is, or if any road is left underneath!  Little more than a foot of moving water can lift a car, and if your car stalls in deep water, leave it immediately.  Fast flowing water more than ankle deep can trip you up, so don’t walk through it.  Stay away from downed power lines. 

What is the First Warning System?

With the KWQC-TV6 First Warning System, you can rest assured that the First Alert Weather Team will be the first to bring you severe weather watches and warnings.  This advanced technology gives you instant warnings with a map of the affected county and a crawl of the essential information.  The bottom line is that the First Alert First Warning System gives you and your family the fast and accurate information that’s necessary to keep you safe.