A little bit of a mixed bag of weather for us over the three day period. Today and tomorrow we will be shaking off our most recent storm but Sunday looks to be nice.

As of 4:00am Thornton had received 5.8 inches of snow. Some additional, light accumulations will be possible today, mainly before noon. After that, more flakes may fall but little / no accumulation is expected. Highs today will top out only in the mid-30s. Tonight, it will be mostly cloudy with a few flurries possible. Overnight lows will be in the mid-20s.

Saturday will see some improvement but still not be all that great. Highs will be in the mid-40s. It will be mostly cloudy initially but then gradual clearing will follow in the afternoon. Some light flurries with no accumulation will be possible. Saturday night, skies will begin to clear and overnight lows drop to the mid-20s.

Sunday will be the nicest day of the period. Look for sunny skies above with calm, dry conditions. Highs will be in the mid-50s.

Have a great weekend!

This is NOT the time to be outside. (michaeljames / FLICKR)

Of all the weather types associated with thunderstorms – hail, tornadoes, floods, etc – lightning is usually the most dangerous. In the United States there are an estimated 25 million cloud to ground lightning flashes each year and each one is a potential threat to life and property.

During the past 10 years there has been an annual average of 39 lightning fatalities in the United States. Last year, 23 people lost their lives due to lightning.

Colorado is ranked # 2 in lightning related deaths (2001 – 2010) so the danger this presents to life and property is very significant for us. It is interesting to note though that Colorado ranks only 32nd in the number of cloud to ground strikes over that same period. Which means, in short, we have fewer strikes than many other states and yet more deaths.

This highlights the fact that, quite frankly, folks here in Colorado are not aware of the dangers lightning presents and they do not take proper steps to protect themselves. One of the great things about Colorado are the outdoor activities we all enjoy, but there comes a time when we need to head indoors.

» Click here to read the rest of Severe Weather 101 – Lightning and lightning safety

We’ve had a couple of false alarms this week, expecting showers the last couple of evenings that never materialized. Today is certain to be different with rain to be followed by snow.

Cloudy skies start us off and will be with us throughout the day. There isn’t really anything to indicate we will get a break in the coverage. High temperatures today will top out in the mid-40s around 1:00pm then begin cooling off early. Winds will be light this morning, becoming breezy in the afternoon and overnight hours.

Early afternoon will see some sprinkles of rain with coverage increasing by about 3:00pm, becoming widespread around 5:00pm. The change to snow, right now, looks to occur around 6:00pm and then light snow will be relatively constant into tomorrow morning. This isn’t going to be a big snowmaker but Thornton can expect 2 to 4 inches overnight.

Low temperatures tonight will drop to the mid-20s.

Straight line winds can be as damaging as a tornado. This image is from a park in Tennessee. (NWS)

During the spring and summer months in Colorado, a wide array of severe weather can strike. Tornadoes may grab all the headlines, but straight line winds and hail can do a great amount of damage in their own right – and they are more common.

Straight line winds are winds out of a thunderstorm and are classified as severe when they hit 58 mph. These winds can reach tornado and hurricane force and as a result, cause property damage and can injure and even kill animals and humans.

These winds are usually the result of air cooling rapidly due to precipitation or evaporation. As the cooler air is heavier than the surrounding warmer air, it rushes downward, accelerating toward the ground and spreads out as it hits, much like pancake batter being poured onto a griddle.

» Click here to read the rest of Severe Weather 101 – Hail and Wind

Another kind of “blah” day for Thornton. Daytime hours should stay dry but it will be cool and cloud cover pretty consistent.

Cloudy to mostly cloudy skies start us off then coverage will ease a bit up until early afternoon when it will again build. High temperatures today will top out in the mid to upper 40s.

At this time it looks like we will stay dry until the evening when we could see some light sprinkles of rain. As it gets colder, some snow but with little to know accumulation will be possible overnight. Lows tonight will dip to the low to mid-30s.

The Big Thompson Flood in 1976 claimed the lives of 144 Coloradoans and serves to remind us of the dangers of floods.

For much of Colorado, floods and flash floods present a grave danger to life and property. These usually are the result of one of two things – spring snow melt occurring rapidly or a severe thunderstorm. Colorado is very susceptible to flash flooding and these occur somewhere every year in the state.

The waters from flash floods can move with extraordinary speed and strike with little or not warning.  Their force can be extremely destructive and when coupled with trees, dirt, rocks and other debris they carry downstream, they are deadly.

Flooding is the number one weather killer in the United States.

» Click here to read the rest of Severe Weather 101 – Floods and Flash Floods

A somewhat dreary day ahead for Thornton. A weak system will keep things cool today but moisture is not going to be amounting to much.

Cloudy skies start us off and will be the general rule throughout the day. We might see the coverage weaken a bit mid-day but gray will be dominant. High temperatures will top out in the mid-40s with some breezy mid to late afternoon winds.

As for precipitation, this morning a few flakes of snow / raindrops will be possible but nothing that amounts to anything. Late afternoon brings another chance for showers, initially rain then changing to snow in the evening.

Overnight tonight, some light snow is expected but accumulations will be light, somewhere around a half inch or so. Lows will drop to around 32 degrees.

The 2008 Windsor Tornado highlights the very real danger twisters present in Colorado. Do you know when to do when one strikes?

One fact that may surprise those new to Colorado is that we are actually on the western edge of the infamous Tornado Alley. This large swath of land comprises much of the nation’s midsection and is a unique place as the United States sees more tornadoes than any other place on earth. In fact, tornadoes have been recorded in all 50 states including Alaska and Hawaii.

Closer to home, Colorado sees our share of these storms. In fact, one metro area county – Weld County – holds the distinction of being the “tornado capital of the world.” With 252 tornados from 1950-2011, no single county in the nation has had more tornadoes! Adams County is number two in the state and isn’t far behind with 156 over that same period.  Granted these numbers are skewed a bit simply due to the sheer size of those counties, but it does serve to highlight the real danger that tornadoes present.

• Think Denver can’t get hit with a tornado?  Think again! Check out the Colorado tornado history map

Even here in the metro area tornadoes are a real danger. The Thornton area was struck in 1981, one of the worst tornadoes to strike the Denver area in history. At 2:30 p.m. this tornado touched down and by 2:45 p.m., the tornado had hit Thornton City Hall. The tornado’s destruction sent 53 injured people to hospitals, 25 homes were destroyed and 239 structures were damaged.

One common myth is that tornadoes don’t strike metropolitan areas. This has been disproved many times including here in Colorado in 1981 when an F2 tornado struck Thornton. Image courtesy the City of Thornton archives.

The most well known tornado outbreak in the metro area occurred on June 15, 1988. Five tornadoes resulted in seven injuries and damage in excess of $15 million.

We all of course also remember in 2008 when the town of Windsor, not far from Denver, was struck with an EF-3 tornado that claimed one life and destroyed and damaged hundreds of buildings.

The greatest threat for tornadoes occurs during late spring and early summer when you have a combination of heat and moisture in the lower atmosphere. Here in Colorado, tornadoes are frequent from May through August with June being the most active month.

However, there is no hard and fast rule for when tornadoes strike, as Colorado witnessed on March 29, 2007 when Holly, Colorado was struck by an EF-3 tornado with winds of 165 mph. Two women lost their lives as a result of that event and 160 homes were damaged.

Colorado ranks 10th in terms of the number of tornadoes with 1,911 events from 1950-2011. One good thing is that our high altitude and drier air do make it harder for the monster supercells that spawn the biggest tornadoes to form. Most of our tornadoes are small and short lived. Further, thanks to the wide open spaces of the eastern half of our state, many strike sparsely populated areas. This is reflected in the fact that we rank 38th for tornado related deaths.

» Click here to read the rest of Severe Weather 101 – Tornadoes and tornado safety

Today is the first in a lengthy string of days of unsettled weather that will last through the week. We start out nice enough today but clouds will be increasing and we may see some light, overnight snow.

Mostly sunny skies will be with us this morning then cloud cover will increase by noon. By sunset it will be only partly clear. Temperatures are going to be on the cool side, some 10 degrees below normal with highs around 50 degrees. Mid to late afternoon will bring some breezy winds.

Tonight, mostly cloudy skies will be above. After midnight, some light snow may fall but with minimal, if any at all, accumulation. Overnight lows will be around 31 degrees.

Looking ahead, every day this week will see below normal temps and some chances for precipitation. Our extended forecast has more details.

The 2008 Windsor tornado highlighted just how dangerous weather in Colorado can be. Are you and your family prepared? Do you know what the watches and warnings all mean?

We’ve all seen TV or Internet news of a weather related watch or warning being issued. But, how many really know what they mean? There is a pretty big difference between the two and it is important to be aware just what it means to you so you can take the appropriate precautions.

Dozens of weather related fatalities occur every year in Colorado, many simply out of ignorance. Taking the time to be aware of the conditions around you and taking appropriate action will keep you from becoming a statistic.

Naturally you can get information on current advisories from television as local stations usually do a good job of “crawling” them on the screen when they are issued. This works well if you have a TV available but if not, the radio would be a secondary source. The Internet and the National Weather Service’s website are a great one when at a computer.

The problem with relying on news media or the Internet is that their ability to warn you of a developing weather situation is dependent on your monitoring them.  Severe weather can strike without little warning.  How will you know if severe weather is about to strike if you don’t have the TV or radio on?

Your first line of defense – NOAA All Hazards Radio

For just about anywhere, a special radio that picks up the NOAA’s All Hazard Radio broadcasts is the way to go and provides information from the source. Oftentimes simply called a weather radio, we highly recommend every household have one of these.

• What does a weather radio sound like? Click here to listen in live.

These radios are relatively inexpensive and allow you to be immediately notified of official National Weather Service warnings, watches, and forecasts as well as other hazard information like earthquakes, avalanches, chemical spills, and even AMBER alerts.  In fact, with these radios, you will be notified at the exact same time the news media is made aware giving you a head start on preparing for a developing situation.

To learn more about these devices and what you should look for when buying one, click here.

A high-tech alternative – Cell phone weather apps

Many people now have smartphones that allow for downloadable apps and weather-related ones are among the most popular.

All of these applications have a number of weather related features in common.  All provide current conditions for either the location the user is in now or for saved locations and all provide some sort of radar.

Most can be configured to sound an alert when the National Weather Service issues a watch or warning.  While they are no substitue for a weather radio, these apps provide you with immediate notification no matter where you are at.

For a look at some of these weather apps and their features, click here.

» Click here to read the rest of Severe Weather 101 – Watches, Warnings and More