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Winter weather patterns explained

Winter weather patterns explained
we are starting to see the changes here come into the state. So one of the things that we want to look at here are how we get winter storms in the first place. *** lot of our setups here in central Iowa that give us our largest winter storms involved. Two setups. The first one is *** colorado low. Usually our systems organized out on the colorado rockies, Then they move east across the Plains into the upper midwest. And usually when we see these type of systems, these are our largest snowstorm producers. As these systems have *** lot of access to gulf of Mexico. One of the things that can make forecasting these fairly hard is the track of the system. If the track is farther south and we end up seeing less snow, but if it's just right, we can see some really heavy snowfall amounts. Another type of system that we get for winter weather is called *** clipper system. These are some commonly referred to as Alberta clippers or Saskatchewan screamers. And the difference here with these is that these are faster moving systems and they don't have as much access to as much moisture. So we typically see lighter snowfall from these type of systems. But those are the two types of systems that can bring winter weather here to central Iowa. Next up, we want to look at precipitation types and really what this depends on is the temperature profile of the atmosphere. So when the surface up to the freezing level is completely above freezing. That's when we get *** cold rain, that's typically what we see *** lot at least during the early part of the winter. But once we start to see the atmosphere cool off, that's when we start to introduce precipitation types, freezing rain sleet and then when we're completely below freezing in the entire column that results and snow. So here's *** good way to remember the difference between freezing rain and sleet, freezing rain. If you want to think of *** food analogy freezing rain is like *** glazed doughnut, the glaze is the ice and that's what we see what happened with freezing rain. It forms *** glaze of ice on all elevated all elevated surfaces. And then sleet are the little ice pellets that bounce around. You can think of that as sprinkles and when we see sleet it all depends on the depth of that cold air. If we have *** larger death of cold air than we typically see more sleet at that depth of cold air near the surface is smaller than that results and freezing rain. So those are your precipitation types. And that's just *** little bit of the science on how we get winter weather here and central Iowa stay safe and we'll continue to track winter weather here. K. C. C. I. As we head into this upcoming season
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Winter weather patterns explained
The warm weather we’ve been experiencing over the last several weeks came abruptly to an end on Thursday, and that serves as a perfect reminder that winter is right around the corner.The National Weather Service designated Nov. 10 as Winter Weather Awareness Day in central Iowa, and we want you to be prepared for the upcoming season here with KCCI Storm Team 8.Central Iowa is no stranger to significant winter weather, so we wanted to look at some common weather patterns that bring us winter weather. The first setup is called a “Colorado Low” in which an area of low pressure develops on the foothills of the Rocky Mountains. Typically, these form in southeastern Colorado, but can also originate in other locations just downstream of the Rockies. Once the low pressure forms and can move east, it advects, or transports moisture northward from the Gulf of Mexico, and that moisture is lifted over a pre-existing cold air mass over the Midwest and Northern Plains leading to the formation of clouds and precipitation.These Colorado Lows typically move slowly and can produce some of our largest winter storms because of their access to plentiful moisture. Forecasting these systems can be a challenge as the path the low takes is crucial for snowfall amounts. One wobble north or south can shift where the heaviest snowfall amounts occur here in central Iowa. The second setup is called a “Clipper System.” These form in the Canadian Provinces of Alberta and Saskatchewan and are often called “Saskatchewan Screamers” or “Alberta Clippers.” Unlike the Colorado Lows, these typically don’t have as much access to moisture and move much faster, resulting in lighter yet still impactful snowfall amounts. Ultimately, the type of winter precipitation we receive during the late fall, winter, and early spring highly depends on the temperature profile of the atmosphere. The temperature profile throughout the atmosphere is not uniform, so this can lead to some interesting and impactful forms of precipitation.When the temperature from the ground to just below the cloud bases is above freezing, this results in just rain. If there is a shallow layer of sub-freezing temperatures at the surface, with a large warmer layer above the surface to just below the clouds, we get freezing rain. Freezing rain can form a glaze of ice that coats objects and surfaces and can even lead to structural damage if there’s enough of it. If there is a deeper layer of sub-freezing temperatures and only a small layer of warmer air in between the cloud bases and the surface, then this leads to sleet. Melted raindrops have time to refreeze into little ice pellets that bounce around and accumulate.Lastly, when the entire column from the cloud bases to the ground is below freezing, this results in snow. There are cases where snow can mix with rain when temperatures near the ground are above freezing, but the temperature in the atmosphere aloft must be very cold to allow this to happen. We hope this explainer helps and makes you more weather aware as we head into this winter.

The warm weather we’ve been experiencing over the last several weeks came abruptly to an end on Thursday, and that serves as a perfect reminder that winter is right around the corner.

The National Weather Service designated Nov. 10 as Winter Weather Awareness Day in central Iowa, and we want you to be prepared for the upcoming season here with KCCI Storm Team 8.

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Central Iowa is no stranger to significant winter weather, so we wanted to look at some common weather patterns that bring us winter weather.

The first setup is called a “Colorado Low” in which an area of low pressure develops on the foothills of the Rocky Mountains. Typically, these form in southeastern Colorado, but can also originate in other locations just downstream of the Rockies. Once the low pressure forms and can move east, it advects, or transports moisture northward from the Gulf of Mexico, and that moisture is lifted over a pre-existing cold air mass over the Midwest and Northern Plains leading to the formation of clouds and precipitation.

These Colorado Lows typically move slowly and can produce some of our largest winter storms because of their access to plentiful moisture. Forecasting these systems can be a challenge as the path the low takes is crucial for snowfall amounts. One wobble north or south can shift where the heaviest snowfall amounts occur here in central Iowa.

The second setup is called a “Clipper System.” These form in the Canadian Provinces of Alberta and Saskatchewan and are often called “Saskatchewan Screamers” or “Alberta Clippers.” Unlike the Colorado Lows, these typically don’t have as much access to moisture and move much faster, resulting in lighter yet still impactful snowfall amounts.

Ultimately, the type of winter precipitation we receive during the late fall, winter, and early spring highly depends on the temperature profile of the atmosphere. The temperature profile throughout the atmosphere is not uniform, so this can lead to some interesting and impactful forms of precipitation.

When the temperature from the ground to just below the cloud bases is above freezing, this results in just rain. If there is a shallow layer of sub-freezing temperatures at the surface, with a large warmer layer above the surface to just below the clouds, we get freezing rain. Freezing rain can form a glaze of ice that coats objects and surfaces and can even lead to structural damage if there’s enough of it. If there is a deeper layer of sub-freezing temperatures and only a small layer of warmer air in between the cloud bases and the surface, then this leads to sleet. Melted raindrops have time to refreeze into little ice pellets that bounce around and accumulate.

Lastly, when the entire column from the cloud bases to the ground is below freezing, this results in snow. There are cases where snow can mix with rain when temperatures near the ground are above freezing, but the temperature in the atmosphere aloft must be very cold to allow this to happen.

We hope this explainer helps and makes you more weather aware as we head into this winter.