Mike's Weather Blog -- May 2006

May 31, 2006 - Severe Weather Possible Again Across Eastern Colo.

May will end on a stormy note for some in eastern Colorado as severe weather once again threatens today.

On Tuesday we saw some severe thunderstorms develop dropping several inches of hail across northeast Elbert County. Heavy rain caused some flooding near Bennett, and hail also fell over Penrose in Fremont County.

One long-lived thunderstorm followed I-70 for about 100 miles before turning southeast and heading into Kansas.

Today could be a repeat performance, only the thunderstorms may be more widespread compared to Tuesday's coverage that was more scattered in nature. We may also see more of the action closer to the Denver area today compared to yesterday.

Once again, large hail and strong winds will be the primary threat. But you can never rule out tornadoes this time of the year.

Stay with 7NEWS today for the latest weather information. Complete coverage will be available here on TheDenverChannel.com and on all our broadcasts.

May 30, 2006 - Severe Weather Will Threaten Eastern Colorado Tuesday

Last night's precipitation helped raise the dew point temperatures across eastern Colorado, ranging from the upper 30s late morning in Denver to the lower 50s along the Kansas and Colorado state line.

Daytime heating combined with that low-level moisture and a bit of wind shear with height will be enough to generate a few afternoon thunderstorms that could turn severe.

Anywhere along and east of I-25 has this threat, but it increases as you head south and east into the more moist air.

Keep your computers on TheDenverChannel.com and your television tuned to 7NEWS for all the latest information today if storms materialize.

Be sure to check out all the fantastic tools on our weather page. There is a button for severe weather to get all the latest watches and warnings, a button for 7 different radar views of Colorado, and My 24/7 Weather to zoom the forecast right down to your location.

May 29, 2006 - Happy Memorial Day

A cold front that passed through the region left a bit of a chill in the air this morning. Mountain locations started out in the upper 20s and lower 30s with a few upper 30s in the Denver area and mostly 40s elsewhere across lower elevations.

Highs today will climb into the 70s east and west with 50s and 60s in the mountains. We have a chance for some afternoon showers and a few thunderstorms.

As always, we just ask that you keep an eye to the sky and seek shelter if stormy weather threatens your area.

Remember that you can zoom the forecast down to your city or town using My 24/7 Weather in the blue navigation menu on this page.

Have a great holiday!

May 25, 2006 - Can It Snow This Late In May?

On this date 10 years ago the Front Range was enduring a soggy late May storm.

By the 26th the foothills picked up 4 to 10 inches of heavy wet snow. It clung to powerlines and caused power outages to over 1,000 homes in the Conifer area.

The unstable air brought some thunderstorms along with the snow, with lightning striking a telephone data cabinet in Conifer. The result was a loss of phone for 1,500 customers.

In the Denver area it was a chilly rain with a widespread 1 to 2 inches recorded.

That is a far cry from the dry and hot weather in place today! But it does clearly show that anything is possible, even this late in the spring season!

By the way, the official arrival of summer is now less than a month away.

May 24, 2006 - Facts About Air Pollution

With the summer ozone season around the corner, I thought now would be a great time to share some facts about air pollution.

There are many connections between vehicle emissions and air pollution. Nationwide vehicles account for 25 percent of all air pollution.

In a year's time, the average car emits 77 pounds of hydrocarbons and 38 pounds of nitrogen oxides. These are key ingredients for the formation of ground-level ozone, especially when skies are clear, winds are light, and the temperatures soar into the 80s and 90s.

The average car also produces approximately 575 pounds of carbon monoxide and over 11,000 pounds of carbon dioxide, both which help to trap heat in the atmosphere.

Now keep in mind this is an average -- newer cars may emit less while older cars may emit more.

Typically cars use over 500 gallons of gasoline each year.

So with these facts, you are encouraged to consider alternate transportation, especially during the summer months. Car pools and public transportation are great options.

One of the best would be a bicycle. Bikes emit no emissions and use no gasoline.

Summer ozone season in the Front Range starts on June 1. This means a daily air quality advisory will be issued each afternoon, for either good or bad pollution levels.

We will have the daily advisory during the weather segment on our forecast graphics.

May 23, 2006 - Much Needed Precipitation Fell Monday

Monday's severe weather outbreak brought the most widespread precipitation we've seen in Colorado for quite some time.

Many places picked up between a tenth and a quarter inch of rain. On the eastern plains, totals ranged from a half inch to over an inch in some locations.

A weather spotter in east-central Lincoln County measured a whopping 1.73 inches of rain!

For totals where you live, log into the CoCoRaHS Web site and click on maps.

May 22, 2006 - Dust Devils Around Denver

Some 7NEWS viewers sent in awesome pictures of a large dust devil in the southern metro area Sunday afternoon.

These look like tornadoes, and sometimes can cause damage, but they are called dust devils. One in Thornton caused damage to a patio set Sunday afternoon, and one in eastern Centennial made for great photographs.

Strong differential heating at the surface on a sunny day with clear skies and light winds cause updrafts to form. As the hot column of air pushes upward through the cooler air above, the air swirls through the column kind of like smoke through a chimney.

As hot air rushes into the bottom of the updraft, it forms what we call a dust devil.

The dust devil will last as long as there is warm, unstable air feeding it. Typically a dust devil is short-lived, less than a minute long.

Usually a dust devil is harmless, but it isn't unheard of for one to cause minor damage or even injuries. Earlier this month a girl was hurt in North Dakota when a dust devil picked her up off a trampoline and dropped her to the ground.

May 21, 2006 - Virga Trails Associated With Afternoon Storms

We talk about high-based storms a lot this time of year as they roll off the foothills and onto the eastern plains. High-based meaning the base of the cloud is high, and due to the dry air at the surface, very little precipitation makes it to the ground.

High-based storms often have virga trails hanging from them. These can be mistaken for funnel clouds. The virga trail is precipitation falling from the cloud’s base but evaporating on the way to the ground.

Pay close attention this time of year to the dew point temperature. When it is in the 30s and lower 40s, you can expect any afternoon storms that develop to be high-based, dry, and gusty. In eastern Colorado, a 45-degree dew point is a good target for storms to develop and turn severe. The higher the dew point climbs, the severe weather and heavy rain threat increases. It’s rare to see dew point temperatures higher than 60 degrees in Colorado.

May 20, 2006 - Great Balloon Launch Weather In Erie

The weather for Erie's Town Fair & Balloon Festival Saturday morning should be delightful, but be sure to bring that sun screen!

By the afternoon it will be on the warm side and a little breezy, with some clouds rolling off the foothills. Much like on Friday, there could be a few scattered high-based thunderstorms.

If you get some great pictures, we'd love for you to upload them to the May Digital Album! Just look for the link under the Weather News button on this page or in the picture above.

May 19, 2006 - Take Action For Better Air Quality

As we wrap up Air Quality Awareness Week, the last thing we need to discuss is how we help improve our air quality. The government has already set forth standards and rules reducing pollution from factories, power plants, diesel trucks, buses and construction equipment. But anytime you use energy, whether it’s gasoline, diesel, electricity or wood, you contribute to air pollution in your communities and those downwind from your location.

Saving energy not only helps reduce pollution and ozone, but can also save you money. Things like setting your air conditioner at a higher temperature, deferring the use of gasoline-powered lawn and garden equipment until late in the day, and refueling cars and trucks after dusk all help reduce pollution. You shouldn’t top off the gas tank and should always replace the gas cap tightly. You can also find cleaner ways to commute, such as by sharing rides with others, using public transportation and combining errands. If painting you should use a brush instead of a sprayer, and buy low VOC paints. You should always properly dispose of household paints, pesticides, and solvents.

You can help reduce unhealthy levels of particle pollution by avoiding burning wood in the fireplace or stove, avoid burning leaves, and replace all filters in your car regularly.

May 18, 2006 - How Air Quality Forecasts Are Made

This week we’ve been talking about air quality, so today we’ll examine air quality forecasts. Over 300 cities around the nation issue air quality alerts based on forecasted concentrations of known pollutants in the air, such as ozone and particulates. But these forecasts aren’t made with the sophisticated computer equipment that weather forecasters use.

Thanks to a partnership between the National Oceanic & Atmospheric Administration and the Environmental Protection Agency, new technology hopes to change that.

These two agencies have recently implemented the first stages of an air quality forecast that reports concentration of ozone in hourly and 8-hour forecast increments. The data is updated twice each day, and the forecast information is valid through midnight the next day.

At this time forecasts are only available for the eastern states, but should become available to the entire lower 48 states this summer. Within the next few years, forecast information will become available for Alaska and Hawaii, and will be extended out several days.

Other forecasts tools in the works include the prediction of airborne particulate matter and a daily smoke forecast tool.

These new resources will help local officials make better air quality forecasts, and in time, provide hourly forecast trends for the entire nation so citizens can take necessary actions.

May 17, 2006 - Staying Healthy When Air Quality Issues Arise

Anytime you breathe polluted air, you are exposed to air contamination. When you exercise, work in the yard, or do other strenuous activities that make you breathe harder and faster, you take even more polluted air into your lungs.

Those most vulnerable to being exposed to air pollution or ozone include children, people with lung disease, the elderly, and people with heart conditions.

When air pollution levels are high enough, they can affect everyone.

You can protect yourself by simply changing the time or intensity of your exercise, yard work, or strenuous activities. Simply use the Air Quality Index (AQI) and daily air quality forecasts to help determine when you should make changes. Think of the AQI as a ruler that measures from 0 to 500 – the higher the value, the worse the air quality and the greater risk it is to your health.

Values of 0 to 50 are considered good, and 50 to 100 are moderate. Values from 100 to 150 violate national standards and are considered Code Orange, or unhealthy for sensitive groups. Values above 150 are Code Red, considered unhealthy for all. Values above 200 are very unhealthy and anything above 300 is hazardous.

May 16, 2006 - Causes Of Air Pollution

Air pollution can have a number of causes, and is high dependable on weather conditions. The levels of air quality can be affected by how much air pollution is emitted in your community, how much is carried in via the winds, and by weather conditions.

Yesterday we talked about ozone and air particles. Ozone only forms when nitrogen oxides and volatile organic compounds cook in the sun. Particle pollution can be directly emitted on the other hand, such as smoke from a woodstove.

A number of things can contribute to both types of pollutants. These include factories, power plants, and mobile sources such as vehicles. Some natural sources can contribute too, including wildfires and volcanoes.

Weather plays a huge role in pollution. Sunlight and heat both play a role in the formation of ground-level ozone. Light winds and a temperature inversion can trap the pollutants near the surface. Winds can also transport pollutants, either brining more in or scouring out the air.

Geography often affects air pollution. Here in Colorado we see this often, especially along the I-25 Urban Corridor of the Front Range. Surrounding terrain can keep pollution from dispersing.

Over 40% of the U.S. population lives in areas with unhealthy air.

May 15, 2006 - Types Of Air Pollution

It’s Air Quality Awareness Week around the nation, and today’s topic is ozone and particle pollution.

There are many types of air pollution, but there are five major air pollutants monitored by the Environmental Protection Agency and the Clean Air Act. They are ground-level ozone, particle pollution, carbon monoxide, sulfur dioxide and nitrogen dioxide.

Ozone and particle pollution are the two most common and the pollutants we hear about the most.

Ozone is a colorless odorless gas, the same as found in the ozone layer. While it protects us from the sun when found high in the Earth’s stratosphere, at the ground-level it is unhealthy to breathe.

When pollutants from cars, trucks, factories, and power plants cook in high heat and light winds at the surface, ozone becomes a problem. We experience the most issues with ozone here in Colorado during the summer, but in warmer climates it can be a problem all year.

Particle pollution, or particulate matter, is also unhealthy to breathe and causes a haze in the air. It can be a problem both during the winter and summer.

Tomorrow we will talk about what causes poor air quality.

May 14, 2006 - Be Air Aware This Week

This week is Air Quality Awareness Week in the United States, and each day beginning Monday the blog will tackle a different topic related to air quality.

Join me in learning more about what you can do to take care of the air we breath each day.

For now, enjoy your Sunday. A very happy Mother's Day to all the moms, including my own in Madison, Wisconsin.

May 13, 2006 - Nice Weekend Weather Ahead

Colorado will sit in a quiet and mild weather pattern this weekend, aside from the chance for a few scattered afternoon thunderstorms.

Your celebrations with mom on Sunday should be great. Just keep an eye to the sky if any threatening clouds develop. Any storms that do form will be short-lived.

To zoom the forecast into your area specifically, use My 24/7 Weather in the blue navigation menu on this page.

May 12, 2006 - Help Mow Down Pollution This Summer

The Regional Air Quality Council (RAQC) is partnering with Neuton Lawn Mower Company and the StEPP Foundation to host the “Mow Down Pollution” lawn equipment exchange to encourage people to upgrade to cordless battery-powered lawn equipment in an attempt to reduce ground-level ozone pollution.

Metro-area residents are encouraged to stop by the event from 9 a.m. to 1 p.m., Saturday, May 13 at INVESCO Field to purchase new, earth-friendly Neuton battery-operated lawnmowers at a deeply discounted price while supplies last, when they retire their older, gas-powered lawn equipment. (At the event $250, normally $399)

In addition, when residents bring a plastic or metal gas can, organizers will recycle it and give them a non-spill, non-permeable can in its place for FREE!

"Older model gasoline-powered lawn mowers produce disproportionate amounts of pollution," said Ken Lloyd, executive director of the RAQC. "And in the hot, summer months, emissions from lawn equipment contribute to the formation of ground-level ozone pollution, which can cause or worsen a variety of health problems for people. By switching to newer model lawn mowers, people can ensure our air quality stays at healthier levels this summer."

In fact, the California Air Resources Board found that, quart for quart, lawn mower engines today contribute 93 times more smog-forming emissions than 2006 cars. Gas-powered lawn and garden equipment -- such as lawnmowers, weed trimmers, and leaf blowers -- causes nearly 10 percent of ozone-forming emissions here on the Front Range of Colorado. Models manufactured before 1997 lawn equipment emissions revisions are particular culprits.

During summer, ozone levels can rise when emissions from vehicles, lawn mowers and other household items "cook" in the hot summer sun. At ground level, ozone pollution is harmful to all of us, especially the young and elderly. Ozone can also trigger attacks and symptoms in individuals with pre-existing health conditions, such as asthma or other respiratory infections.

Tips on preventing ozone pollution from lawn equipment include:

Delay mowing until evening.

Use a new, earth-friendly lawn mower -- a battery or electric-powered mower, a non-motorized push mower, or a new gasoline-powered mower

Avoid using two-stroke gasoline-powered yard equipment, such as weed trimmers, since they emit a disproportionate share of air pollution.

Maintain your mower to help it run cleaner -- change the air filter, oil and spark plugs at least once each season. Keep the underside of the mower free of grass build-up.

Use a funnel to refuel equipment -- avoid even small spills and drips.

The event will take place at INVESCO Field at Mile High in Parking Lot F on the southeast corner of Federal Boulevard and W. 19th Avenue.

May 11, 2006 - Quiet, Mild Forecast Statewide

After a frosty start, with just about everyone in the upper 20s and lower 30s around northeast Colorado, we'll start a warming trend today that will last through the weekend.

The mountains will even be mild after some places started out in the upper teens today.

We could even see some 80s show up on the temperature map by Friday and Saturday on the eastern plains.

With the daytime heating, there will be a chance for a few afternoon thunderstorms over the weekend, but no washouts are expected.

So go ahead and plan a really nice meal for mom, maybe cook out on the grill!

May 10, 2006 - Overnight Showers, Even Some Snow

It's May in Colorado! Showers and some cooler air pushed through the Front Range overnight, with some wet snow mixing in as low as 5,000 feet! Just enough cooler air working in from the north, combined with evaporative cooling aloft, aided in turning some rain over to snow.

It was just nice to see some moisture, no matter how it fell!

Grab a light jacket or sweater before heading out, we've got one more day of cool weather in store before a warming trend begins.

Check the precip reports from where you live by logging onto Colorado's Water and then clicking on the mountain snowpack & water supply icon.

Tomorrow is the Youth Water Festival in Aurora. More than 1,000 5th graders from Aurora Public Schools will be in attendance.

This event, hosted by Aurora Water, is one of the largest educational water events in Colorado!

May 9, 2006 - Cooler, Unsettled Today

Another cold front has swept through the area, bringing clouds and scattered showers or thunderstorms to the area today.

The cooler temperatures and higher humidity are good for keeping the fire danger at moderate to low levels. Hopefully your area will get under some of the passing showers.

Today I will be up in Greeley at the Children's Water Festival moderating the Water Wizards event. Students attending the festival will compete in a quiz bowl by answering all kinds of water and water related questions.

Speaking of water and related issues, be sure to click on Colorado's Water while visiting TheDenverChannel.com today! It can be found in the blue navigation bar on this page.

In Colorado's Water you can explore numerous topics, including watersheds and fire weather.

You can also check out the current events calendar to see what may be coming up in your community, such as cleanups on area waterways.

May 8, 2006 - Here Comes Another Cold Front

Another cold front is on the move toward Colorado, with showers and thunderstorms possible as early as this afternoon. Cooler weather will move in for Tuesday, and Wednesday could actually be much like what we saw last Friday. Right now highs are only expected in the 50s with morning drizzle and fog.

We'll see a nice recovery for the weekend with a return to mostly sunny skies and highs in the 70s.

May 6, 2006 - Get Real-Time Water Information

If you are looking for real-time stream and river information you can get that plus more right here on TheDenverChannel.com!

Just click on Colorado's Water in the blue navigation menu on the left. Then click Find Your Watershed and choose real-time data.

Have a great weekend and enjoy clicking around on the website.

May 5, 2006 - Weekend Will Start Cloudy, End Sunny

If you have any outdoor plans, it will start off cool and cloudy with rain showers today, lasting into the morning hours Saturday. Things will begin to clear up as we head through the day tomorrow, with Sunday being the pick weather day this weekend. Expect sunny skies and lower 70s.

Need a more detailed forecast? Click on the My 24/7 Weather button in the blue menu on the left of this page. Then select the metro area, state, or national map. With your mouse, click where you live and it will give you the hourly forecast for the next 48 hours.

This free service is only offered by 7NEWS and is updated four times each day.

May 4, 2006 - Cool And Damp, Great For The Landscape

It is a bit on the cool and dreary side, but look how green things will be compared to the past several weeks! This type of weather is exactly what we need to delay the rapidly approaching fire season.

So if the weather is spoiling some plans you might have made today or tomorrow, just think of how beneficial this is and it will hopefully make things better.

Good news! The weekend should for the most part be great! We'll likely have some departing sprinkles and/or clouds Saturday morning, but by afternoon and through the day Sunday, a warming and drying trend will be in place.

The next chance for cooler and damp weather will come about this time next week based off current data.

May 3, 2006 - Can Fish Be Hit By Lightning?

A 7NEWS viewer called Tuesday curious if lightning strikes on a body of water can harm things like fish, whales, and other sea life. It is a very interesting question!

As we all know, water isn't the place to be when it is storming outside. Water is a very good conductor of electricity.

When water takes a direct hit, the current is mostly spread out on the surface, with very little electricity penetrating down into the water. This is because the water neutralizes the strike.

While fish directly under the strike or near the surface could be shocked or killed, most will be safe as long as they are well below the surface.

May 2, 2006 - Cold Front Approaching

A cold front approaching from the north will bring a midweek cool down, an increase in clouds and humidity, and a chance for some showers.

Out ahead of the front today it will be warm and windy with moderate to high fire danger, so be extra cautious when outdoors.

Behind the front we are looking at mid 50s to mid 60s over the next few days with partly to mostly cloudy skies.

May 1, 2006 - May Flowers

The old saying goes 'April Showers Bring May Flowers' may just happen thanks to some recent moisture around the state. In fact, just late last night showers and a few rumbles of thunder passed through eastern Colorado.

May can be a wild month with everything from severe thunderstorms to hail, and temperatures in the 90s to near 100 degrees down as low as 20 degrees.

We'll usually see our first 90 degrees temperature this month.

May is also the wettest month of the year on average with 2.32" of moisture falling over Denver. Average snowfall is about 1.3 inches. Typically we see precipitation every three days this month.