A cool front touched off a few thunderstorms Monday evening. But that’s on its way out and Tuesday will reveal a very nice weather pattern! High pressure will be right overhead Tuesday night and Wednesday. This will bring us highs in the 70s and lows in the 50s. In fact, upper 40s may be as close as South-Central Wisconsin Tuesday night!

However, as this high pressure drifts to the East Coast this weekend, it will open up the warm air to move in from the west. The level of warmth would be enough to warrant 90s in our forecast, if we could get rid of the 30-40% chance of thunderstorms. At this point, it’s just too hard to determine when the weekend thunderstorms will occur. Should they happen in the morning hours, it will be impossible to warm into the 90s. Should we remain dry through the afternoon hours, 90s will be a sure bet. In any event, summer begins Friday and will feel like it! -Eric

Posted under heat wave, weather geek

Chris Novy, an experienced Stormchaser was on the roads of Oklahoma City after Friday’s tornadoes, but during Flash Flood Warnings. Because he had a dash camera to document the storms, his ordeal was caught on camera.

 
Chris shares his experience because there are lessons to be learned. He says “I approached a flooded road and made a quick U-turn rather than driving into the water. This was a naturally smart move. Unfortunately my turn resulted in me plunging off a hidden embankment and splashing nose-first right into a swollen creek where I sunk straight to the bottom, I traveled several hundred feet underwater with the car quickly filling up. At one point I was completely surrounded by water and just holding my breath in the darkness. Somehow the driver-side and passenger-side windows broke and I was flushed from the vehicle. I surfaced after a bit and found myself racing down the creek. A cop called out to me and I was able to swim to him and his life-saving grab.” Thankfully, Chris is able to share his story of survival in the hopes of saving someone else’s.

While the phrase “Turn around, don’t drown” is something we Meteorologists use frequently during heavy rain, please remember Chris’ story and never drive through a water-covered roadway. He advises you to “leave more time to process your surroundings.” And that’s not too much to ask!

Posted under flooding, tornado, weather, weather geek

Today, we got quite a few reports of “possible tornadoes” including one spotted by several law enforcement officials in Whiteside Co. The National Weather Service Forecast Office in Davenport will be looking at any damage there on Friday, in order to determine what kind of damage was done there.

In the meantime, we received quite a few unconfirmed reports of tornadoes in Ogle County. After examination of storm photos, this was not a tornado…but a gustnado. What’s that you say? Let’s go in-depth.

 First let’s look at this example of a tornado. The storm is moving from left to right so picture yourself looking north into the storm.
More often than not, a severe storm with a tornado will produce heavy rain and hail with strong, gusty wind coming down from high within the storm. Then, once the rain and hail comes to an end, a tornado will exist at the bottom of the storm’s updraft. Finally, as the storm moves from left to right the rear-flank downdraft (often called the RFD) comes in to produce additional wind damage.

So that’s a tornado…most likely NOT what we had tonight.

Instead, let’s look at the diagram of a gustnado. Again, the storm is moving from left to right. Instead of the rain and hail coming first, a swirling vortex is seen BEFORE the storm. In all of the photos I’ve observed today, this vortex was not attached to the storm iteself. Instead, the wind moving out on the front side of the storm began swirling and created a gustnado (in short, a tornado on the gust front).

After seeing photos of the gustnado and hearing reports, it’s likely this was a strong one tonight! Trees and power lines were taken down in its path…and if a survey team assesses the damage, it’s likely to be classified as a gustnado with a rating on the Enhanced-Fujita Scale (the scale used to rate tornadoes).

Posted under severe weather, weather geek

Tonight, we observed a pretty spectacular shelf cloud ahead of a line of severe thunderstorms. But shelf clouds are often mistaken for wall clouds, which produce tornadoes.

Let’s take a look at a case example. On the left, a wall cloud. On the right, a shelf cloud, taken by Vicki Lay in Davis Junction, Illinois tonight. At first glance, they look extremely similar. However, they are indicators of much different weather.

A wall cloud hangs lower than the base of the thunderstorm cloud. In this example, a tornado would form in the middle of the lowering part of the rotating wall cloud. Most of the time, you can observe the wall cloud actually spinning, albeit quite slowly to the naked eye.

A shelf cloud on the other hand (right) is a wide row of clouds arcing out ahead of a thunderstorm. In Vicki’s case, the storm is moving from right to left. A lot of times, there are low-hanging clouds under the base of the shelf. These are called scud clouds. A lot of times, scud clouds hanging from the bottom of a shelf are mistaken for funnel clouds. However, if you observe scud clouds, they may have upward movement but rarely spin.

Good rule of thumb is when you see a real funnel cloud, you’ll know it! You will definitely be able to observe the spin. And remember the old-fashioned stormchasing saying “If it doesn’t spin, don’t call it in!” -Eric

Posted under weather geek

During the late winter and early spring, the reservoir of cold water known as the Great Lakes can cool surrounding areas considerably! Today, we shot into the 70s while much the big cities and suburbs to our east saw 60s. A northeasterly wind in March and April can bring our temperatures down by as much as twenty degrees. However, with water temperatures rising into the 50s now, the strength of that cooling will become confined to areas closer to the lakeshore. Still, as we know, that “cooler by the lake” phrase will be used quite a bit by our Meteorologist friends in Milwaukee and Chicago. However, in a few weeks, it will be pretty hard to get that cooling this far inland.

More importantly, will be the cold bursts of air from Canada…and there’s one coming for the weekend. Models are consistent in bringing a cold front through the area Saturday. Depending on the strength of the airmass behind it, temperatures may only top out in the lower 50s by Sunday…a far cry from this past weekend.

However, don’t fret. This is way out on Day-6 of our 7 Day Outlook. We could see this cold air modify a bit and even delay, which could cause us to bump up those forecast highs.

Posted under cold blast, weather geek

Saturday marked just the fourth time where temperatures climbed to 70 degrees or more in Rockford.  If you were like me, you probably enjoyed it!  The mild weather has been lacking across the Stateline for much of the year.  When reviewing all 124 days of 2013 (January 1 through May 4), just 15 days have had high temperatures at or above 60 degrees! That’s only 12 percent of all days so far. That figure lowers to just 3 percent, when reviewing days of 70 degrees or greater!

While only one day rose above 60 degrees in January, no days had high temperatures in the 60s (or higher) in February and March!  April saw ten days with high temperatures in the 60s. But it wasn’t until April 29 when Rockford broke the 70 degree mark (75 to be exact)—nearly one month later than the average first 70-degree day!

The forecast for the first full week of May will bring an end to the mild weather drought, so to speak, with at least 5 days at or above 70 degrees! -Joe

Posted under 13 Climate Authority, statistics, weather, weather geek

Have you been sniffling and sneezing? Tis the season for allergies and the weather has a lot to do with how you may feel. This week, we were invited to the laboratory at the Winnebago County Health Department to see how the pollen is counted. On the roof is a machine, dubbed the “RotoRod” spins a sticky piece of plastic for one minute, every ten minutes, for 24 hours. Some of the pollen that floats through the air sticks to the plastic. Each morning, scientists in the lab must climb a ladder to the roof of the building and collect the sample.

Larry Swacina, Director of Environmental Health says “You don’t realize there’s small little world of this entire world of this small little particles of living things. it’s just fascinating to look under the microscope and see all of that.”

The sample is brought back to the lab and inserted into a microscope where certain types of pollen are identified. For instance, pine tree pollen has little wings which allows it to ride the wind, traveling longer distances. Ragweed pollen is spiky, which causes big problems for sufferers.

Once each pollen is identified, the sample is analyzed which allows the lab tech to determine how much grains of pollen is in a typical cubic foot of air.

Swacina says it’s important to sample each day’s pollen because of our aging population as he believes more people are developing allergy or asthma symptoms.

You can get each day’s Allergy Report on 13News at Noon and 5pm each weekday.

Posted under weather, weather geek

Today’s 87 degree high temperature in Rockford was just four degrees off the record high for the date! It’s hard to forget the heat of 2012, but to put this warmth in perspective, check out the amount of time that has elapsed since September 12th when the mercury soared to 89 degrees! Almost 20 million seconds ago.

Wednesday will be warm once again, although likely a few degrees cooler. Look for highs in the middle 80s once again before a much cooler weather pattern takes hold from Thursday on. -Eric

Posted under weather geek

We have had some serious flooding in the past few weeks. But if I saw this, I’d be running away! What do you think? -Eric

Posted under news, weather geek

April 14, 2013 High Temps

An interesting scenario was observed on Sunday. A warm front traveled north during the late morning hours and set up shop along the Illinois-Wisconsin border. North of the warm front, the wind blew out of the east.  The cool water temperatures of Lake Michigan helped to moderate the air mass and kept a chill in the air. As a result, much of our southern Wisconsin counties had temperatures stall in the upper 40s and lower 50s.

South of the warm front was a different story! With a south to southeast wind, many communities along and south of Interstate 88 and west of Interstate 39 climbed into the lower 70s! Freeport, Rochelle, DeKalb & Galena all recorded their first 70-degree temperatures of the year.

Temperature vs. Wind Direction

The Rockford & Belvidere area was in somewhat of a transition zone.  The warm front lifted north of the metro area around 2pm and allowed temperatures to climb into the upper 60s. However, around 4:30pm the front sagged to the south. As a result, the wind direction shifted from the mild southerly breeze to the cool easterly breeze and temperatures fell into the upper 50s around dinnertime.  Not long after sunset, however, the front moved back north of the metro area.  Even without the help of the sun, the warm air advected from the south and temperatures climbed back into the middle 60s!

-Joe

Posted under weather, weather geek, Wind