Thursday Text Poll

They say the first thing to go is your memory…and I am afraid I’ve succumbed. After forgetting to post the question on Wednesday night last week, I remembered tonight! So, here you go:

We’ve been teased when it comes to snow this autumn. So we want to know if you are ready for the season’s first big snowstorm. Text the word ERIC to 24104 to vote. And watch your vote add up on 13News 10@10 Thursday night. ‘Text STOP to end, text HELP for help’ -ES

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Posted under Text Poll

This post was written by qni_it on November 30, 2011

More snow to the northwest? More cold for us.

Only parts of the Upper Midwest lie under a blanket of snowcover today (areas shaded in gray), but two storm systems will put down additional snow to our northwest in coming days. And this additional snow will put next week’s airmass on ice…literally!

Winter Weather Advisories are in effect for the Dakotas as at least a few inches of snow will fall there in the next two days.

Over the weekend, a storm system will scoot pretty close to us laying down a new blanket of snow from Nebraska through southern Minnesota, and Northern Wisconsin.

Each of these snow events “fills in” the void of snowcover to our northwest. Once we get into a northwesterly flow early next week, the air will remain colder as it travels over a cool snowpack versus the warm, bare ground. -ES

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Posted under cold blast, weather, weather geek

This post was written by qni_it on November 30, 2011

Winter’s sunny days are rarely calm & warm

Today’s sunshine was a welcomed sight across much of the Midwest after a windy and snowy day for Indiana and Michigan yesterday.

As we head into the winter months sunny and warm days will only occur with a considerable amount of wind, or they’ll be downright cold!

Let’s look at three different sunny scenarios for the Upper Midwest. First, the sunny, windy, and warm day. This usually occurs when a strong high pressure system lies to our southeast. If the temperatures are quite significantly above normal, there’s probably a sizable low pressure system to our northwest (as I’ve put in this graphic). This allows the air to stream between the two systems from the southwest. Remember the tornadoes that affected Caledonia and Poplar Grove in recent years? This was the set up that brought the record high temperatures before the tornadic thunderstorms.

The next scenario to look at is the exact opposite of the previous one: the sunny, windy, and cold day. You can see, all I did was switch the placement of the low and high pressure systems…and reversed the wind direction. This is the scenario we had yesterday that brought all of the snow to Indiana and gave us 40mph wind gusts here in the morning. This weather pattern shows a relatively weak low pressure system working from southwest to northeast and an incoming stronger Canadian or Pacific high pressure system. If the high pressure system is stronger than the low, or the low is far enough to our southeast, we have sunshine, wind, and cold. In the heart of January, be on the lookout for this type of pattern as the coldest wind chills occur with this type of pattern.

In the winter it is almost impossible to have an above normal, sunny, and calm day. The reasons? First, we have more hours of night than daylight so our solar budget is in a deficit…and it’s colder. Second, calm days and nights are usually caused by high pressure systems. High pressure systems in winter typically originate in the higher latitudes of Canada with colder airmasses. Even if there is a high pressure system that arrives from the southwest or west, it’s still typically colder. That’s because the light wind at night causes any warmth built up during the day to be radiated into space.

To make a long story short, it’s very rare to have a warm, sunny day with little/no wind in the winter months. By the way, our three-month Meteorological winter begins tomorrow. -ES

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Posted under weather geek

This post was written by qni_it on November 30, 2011

Tomorrow is the first day of Winter… No Joking!

Today is the last day of meteorological fall, which includes the months of September, October, and November.

Now, many of you may think winter starts on either the 21st or 22nd of December, but to every meteorologist on this planet, winter starts tomorrow. Meteorological winter is the three coldest months of the year (December, January, and February.) Those three months feature the lowest average temperatures out of the entire year. In December, Rockford’s average temperature on the 1st is 38°F.  By the time we hit the end of the month, our average will be ten degrees colder. The astronomical first day of winter is December 21st.  That is when we have our lowest sun angle, which also means our shortest day of the year.

The graphics show what our friends at the Climate Prediction Center (CPC) think our meteorological winter might be like.

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Posted under climate/climate change, weather, weather geek

This post was written by qni_it on November 30, 2011

Goose bump weather is typical this time of year

If you thought it was cold today, just remember that December begins in two days. The average high temperature is now 39 degrees which means today was actually above average.

The meteogram to the left shows the projected high and low temperatures over the next week. Aside from tomorrow and a brief spike in temperatures on Thursday, we’ll be undergoing quite the cooling by the weekend into next week. Temperatures could dip as low as 10 degrees both Monday and Tuesday morning if the GFS model verifies.

So, grab the heavy coats! -ES

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Posted under cold blast

This post was written by qni_it on November 29, 2011

Hour-by-Hour Wind Chill Forecast

The powerful storm system that is swirling along the eastern part of the United States will cause us to feel harsh conditions today.  It will not just be the lack of sunshine today; it will be the north winds gusting as high as 40-45 mph.  This will allow our wind chill factors to be very cold.  Highs today will be in the mid and upper 30s.  However with gusty north winds around 40 mph, it will make our temperatures feel like the lower to mid 20s.  To plot out your day accordingly, the graphic to the left shows a 9-5 schedule of temperatures and wind chills.  Therefore, if you have to go run an errand around 2pm, you have an idea of how cold it really feels once you step outside.

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Posted under weather

This post was written by qni_it on November 29, 2011

Don’t put all your eggs here…

…but the evening GFS computer model has come in with a snowy solution for Saturday night and Sunday. (This really doesn’t deviate from our 7 Day Outlook much however.)

I based most of my forecast this afternoon on the ECMWF model which is usually the best at handling cold systems like this. However the ECMWF didn’t have much of a low pressure system developing along the cold front that will slide through Saturday. The new GFS model (left) develops a low over East Texas and tracks it into Indiana and Michigan. If this model is correct it would bring us a winter storm. Important: this is one model run and it, and all the others, will change significantly…especially since these models are trying to resolve energy that has yet to enter the continent! Watch Tuesday around 4:30pm as our exclusive Storm Probability (on the side bar) changes with our afternoon forecast package. -ES

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Posted under winter storm

This post was written by qni_it on November 28, 2011

WREX Probability Scale

Here at the 13 Weather Authority, we do not forecast snowfall amounts until a system’s onset is within 24 hours of Rockford. We began this practice at the beginning of the winter season two years ago for a few reasons. First, we are able to give a more accurate forecast once instead of changing the outlook depending on small nuances in stormtrack and intensity. It also made it easier for us to verify our forecast after the fact since we then had a forecast amount versus actual reports.

However, as soon as snow makes its way into the forecast, most people want to know what the prospects are…whether it will be a small, nuisance snow versus an ice storm or even a full-fledged winter storm!

So, how do we accurately forecast this when we may not have all of the answers a few days out? Obviously, we have an idea of how the solution would be if it warrants us putting a wintry movie under a day on the 7 Day Outlook. Because of this, I developed a “probability scale” so you can get an idea of what is possible versus what will happen exactly.

Below is the current probability scale for the system that will affect the Rockford region this weekend. You will find this on the side bar of the main blog page (to the right). On specific blog posts, it may appear on the left side of the page. Because this is a new trial for me, I will update this Monday through Friday around 4pm. If it seems to be a well-liked addition to the blog, I will update it every day at 4pm.

First, we will give a probability of snowfall accumulation of at least one inch.

Next, because a 2 inch snow is drastically than a 6 inch snow, there is a probability of each condition being met, 2″, 4″, 6″, 8″, 12″, and 18″.

Because there are systems that don’t just yield snow, there is a probability of the storm giving us all snow, all rain, or a combo of rain, sleet, snow, and ice.

Lastly, there is a probability of the amount of precipitation (either rain or melted snow).

I’d like to hear from you about this trial. Does this give you the right amount of information ahead of time? Honestly, it’s hard to get specific when I don’t have all of the details. I hope this lets me get the information across to you in a timely fashion. Thanks in advance for your input! -ERIC

Sat PM through Sun PM
Exclusive WREX Probability Scale:
* 24% Snowfall Accumulation
* 10% Snow > 2 in.
* 02% Snow > 4 in.
* 00% Snow > 6 in.
* 00% Snow > 8 in.
* 00% Snow > 12 in.
* 00% Snow > 18 in.
* 20% Precipitation type: All Rain
* 30% Precipitation type: All Snow
* 50% Precipitation type: Hybrid
* 27% Precipitation >0.25 in.
* 12% Precipitation >0.50 in.
* 01% Precipitation >1.00 in.
* 00% Precipitation >2.00 in.

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Posted under weather geek

This post was written by qni_it on November 28, 2011

Wind here, rain for Chicago, and snow for Birmingham and Tupelo?

A developing area of low pressure across the Tennessee River Valley has Winter Weather Advisories posted for Memphis, Huntsville, and Birmingham, Alabama tonight for a dusting to a few inches of snowfall. A Winter Storm Watch is in effect for the purple shaded areas including Tupelo, Mississippi. This will be one of the earliest snow events the south has seen in decades! Even though only a few inches of snow will fall, this may be classified as a “winter storm” based on certain criteria from National Weather Service offices in the area.

Even though these areas to the south will receive snow overnight, we will have rain close by on Tuesday. Areas east of I-55 in Illinois from Bloomington to Joliet and Chicago could see some healthy doses. Points east will have the potential of seeing 1-2 inches of rainfall (shaded in yellow). Why are snowflakes flying 600 miles south of here when rain is possible this far north? As the low pressure deepens, it is able to intake cooler air from higher altitudes. In addition, the system will be producing heavy amounts of rainfall initially, which will end up cooling the atmosphere. Because areas like Chicago will be on the fringes, rain is the primary threat with some mixing possible during the nighttime hours. Note: There is no reason to panic looking at western Michigan’s snowfall at this point. Our model is putting down more than a foot of snow in this area! That’s a huge stretch at this point…

For us, our big story will be the strong wind in response to a strong ridge of high pressure to our west and this low pressure moving northward into Ohio. We are projecting peak wind speeds to exceed 25mph Tuesday afternoon with some wind gusts above tropical storm force (43mph). By nightfall Tuesday, the wind chills will dip significantly with a low wind chill around 14° Wednesday morning. So, get ready for a windy, cold day Tuesday! -ES

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Posted under rain, weather geek, Wind, winter storm

This post was written by qni_it on November 28, 2011

Tuesday’s Forecast Could be Worse

Our next storm system will just miss us to our east as it slides through the Ohio Valley Tuesday.

The weather conditions that we will have to deal with Tuesday are gusty winds and cold wind chill factors.  Winds will be sustained out of the north around 15-25 mph with peak winds up to 35 mph.  With temperatures only reaching into the mid and upper 30s, our wind chill factors will range in the lower 20s.

Now think about this: If the storm system were moved 100 miles to the west, we would have to deal with a whole other ordeal.  In northern Indiana, which is just 100 miles to our east, they will have to deal with wind driven rain during the day, then a rain/snow mix that afternoon.  Winds will gust up to 45 mph, with an estimated one to two inches of rainfall.

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Posted under weather, weather geek

This post was written by qni_it on November 28, 2011