10:59pm – Severe weather threat has for the most part ended. There is still a chance of additional thunderstorms developing, especially northwest of Freeport (As the storms in Eastern Iowa move eastbound). -Eric

10:25pm – Severe weather is ongoing around the Chicago area (and the south suburbs). Additional thunderstorm activity is tracking through Eastern Iowa. For the most part, this limits any severe potential. However, we’ve seen some 60mph wind gusts even where no rain is falling. This occurs as a low pressure system develops in the wake of developing severe thunderstorms. Please report any gusty wind to us at weather@wrex.com. -Eric

9:15pm – Watch live coverage here!

9:00pm -Severe Thunderstorm Watch for all areas through 3am. We will be posting all severe weather information here. -Eric

7:30pm – All eyes on an arcing batch of thunderstorms developing around Galesburg right now. These are expected to congeal into one, large storm as they move northeast. If this occurs, they will be in Whiteside County by 8:30 and the Rockford Metro before 10pm. Damaging wind would be the main threat, second to large hail, and a remote chance of a tornado.

In addition, within the past minute, a Tornado Warning was issued for the cells just north of Des Moines. However, these storms will move into Western Wisconsin, well northwest of our coverage area.

Please remain alert for rapidly changing weather later this evening and think about your safest place for shelter (likely in the most interior room, away from windows, preferably in the basement under the stairs). -Eric

Posted under severe weather

As we head into this afternoon we will see our sunshine become destructive in nature as it heats a very unstable atmosphere. Warm moist air from the Gulf of Mexico is being pumped into the Midwest with the jetstream (and a cold front) lined up just to the west. The combination of these ingredients could lead to the formation of heavy thunderstorms later this afternoon into this evening. Damaging wind, hail, and even a slight chance for the development of tornadoes is possible. Stay tuned here on the blog as things unfold this evening. -Greg

Posted under rain, severe weather, tornado

Midnight Radar

12:35pm Update: All local Severe Thunderstorm Warnings have ended. A line of showers and weakening thunderstorms will push east across the Stateline for the next hour or two. Although below severe limits, some brief gusty wind and small hail are still a possibility. -Joe

12:00am Update: Severe Thunderstorm Warning for Jo Daviess, extreme northwest Carroll, and extreme northwest Stephenson County until 12:30am. Quarter-size hail and wind gusts up to 60mph can be expected as this storm races north-northeast into Wisconsin. -Joe

10:15:15 PM) nwsbot: Local Storm Report by NWS MKX: 3 NNW Beloit [Rock Co, WI] law enforcement reports TSTM WND DMG at 09:02 PM CDT — tree went through roof of home on afton road between afton and beloit.

(9:40:36 PM) nwsbot: Local Storm Report by NWS LOT: Rockford [Winnebago Co, IL] trained spotter reports HAIL of half dollar size (E1.25 INCH) at 08:59 PM CDT — quarter to half dollar size hail 2 miles west of downtown. time estimated.

(9:24:31 PM) nwsbot: Local Storm Report by NWS LOT: 10 SE Durand [Winnebago Co, IL] amateur radio reports TSTM WND DMG at 09:13 PM CDT — estimated 25 to 30 inch diameter tree down on route 75, approximately 1.5 miles east of merridian road.

(9:22:17 PM) nwsbot: LOT issues Severe Thunderstorm Warning [wind: 60 MPH, hail: 1.00 IN] for Boone, Cook, De Kalb, DuPage, Kane, Kendall, Lake, McHenry, Will [IL] till 10:30 PM CDT

(9:18:39 PM) nwsbot: Local Storm Report by NWS LOT: Belvidere [Boone Co, IL] emergency mngr reports HAIL of pea size (E0.25 INCH) at 09:13 PM CDT — estimated pea sized hail at beaver road and beaver spring.

(9:05:34 PM) nwsbot: Local Storm Report by NWS LOT: Rockford [Winnebago Co, IL] broadcast media reports HAIL of penny size (E0.75 INCH) at 08:57 PM CDT — dime size hail in downtown rockford.

(9:01:48 PM) nwsbot: Local Storm Report by NWS LOT: 5 NW Polo [Ogle Co, IL] co-op observer reports TSTM WND GST of E50 MPH at 08:05 PM CDT — estimated 40 to 50 mph wind gusts on leading edge of thunderstorms. small tree branches down.

Tornado Watch until 3am

(9:00:03 PM) nwsbot: Local Storm Report by NWS LOT: Rockford [Winnebago Co, IL] amateur radio reports HAIL of penny size (E0.75 INCH) at 08:56 PM CDT — dime size hail on charles street.

(8:55:01 PM) nwsbot: Local Storm Report by NWS LOT: Pecatonica [Winnebago Co, IL] trained spotter reports HAIL of golf ball size (E1.75 INCH) at 08:47 PM CDT — golfball size hail near trask bridge and eddy roads.

(8:56:50 PM) nwsbot: Local Storm Report by NWS LOT: N Rockford [Winnebago Co, IL] emergency mngr reports HAIL of pea size (E0.25 INCH) at 08:52 PM CDT — pea size hail near latham and rockton ave on the north side of rockford.

(8:49:10 PM) nwsbot: MKX issues Severe Thunderstorm Warning [wind: 70 MPH, hail: 1.75 IN] for Green, Rock [WI] till 9:45 PM CDT

(8:32:09 PM) nwsbot: Local Storm Report by NWS LOT: Franklin Grove [Lee Co, IL] broadcast media reports TSTM WND GST of E60.00 MPH at 08:20 PM CDT — estimated gust to 60 mph. severe dust storm reported with near zero visibility.

(8:25:55 PM) nwsbot: LOT issues Severe Thunderstorm Warning [wind: 60 MPH, hail: <.75 IN] for Boone, De Kalb, Lee, McHenry, Ogle, Winnebago [IL] till 9:30 PM CDT

(8:20:39 PM) nwsbot: DVN cancels Tornado Warning for Carroll [IL]

(8:07:46 PM) nwsbot: DVN issues Tornado Warning [tornado: OBSERVED, hail: 1.25 IN] for Carroll [IL] till 8:30 PM CDT …AT 802 PM CDT…A CONFIRMED TORNADO WAS LOCATED NEAR ARGO FAY…AND MOVING NORTHEAST AT 40 MPH.

7:45pm Update: The Severe Thunderstorm Warning was extended until 8:30pm for Whiteside and Carroll County. Lee and Ogle County are now included as well. Line of storms is racing northeast at 45mph with strong gusty wind and sizeable hail. Frequent lightning and heavy rain are also likely. -Joe

7:30pm Update:  A Severe Thunderstorm Warning is in effect for Whiteside County until 8:15pm. A strong storm was moving northeast at 45mph with 60mph wind gusts and nickel size hail. Erie, Prophetstown, Tampico, Lyndon, Walnut, Deer Grove, Sterling, Rock Falls and other nearby communities are in the path. This storm will likely move northeast into Lee and Ogle County after dark. -Joe

5:30pm Update: A Tornado Watch is in effect until 10pm for the local counties of Carroll, Jo Daviess, Stephenson & Whiteside. Severe thunderstorms have fired up south of the Quad Cities and are trackin north.

3:30pm Update: A Tornado Watch is in effect for a land area stretching nearly 1,000 miles from southern Oklahoma into southern Minnesota. The Tornado Watch includes most of Iowa and four counties in extreme western Illinois, not too far away from the Stateline. As of this update, only one warned storm was present in northern Iowa. More development is expected there throughout the rest of the day. We will have the threat for severe thunderstorms area-wide later this evening and tonight. This blog post will be updated periodically as things change or develop. -Joe

7:40pm Radar

3:00pm Update: The Severe Thunderstorm Warning has been cancelled for Stephenson County. A new warning is in effect for Green and northwest Rock County in Wisconsin until 3:45pm. There have been numerous reports of downed limbs and trees with wind gusts up to 70mph. Hail and heavy rain is likely with this small line of storms as well.

2:30pm Update: A Severe Thunderstorm Warning is in effect for Stephenson County until 3pm.  A Severe Thunderstorm Warning is also in effect for Green County and northwest Rock County in Wisconsin until 3pm.

A small line of storms is moving northeast around 45mph and will affect areas along and north of US Highway 20 and Illinois Route 75.  Wind gusts up to 70mph have been observed as well as pea to penny size hail, frequent lightning, and torrential rain.

Seek shelter if you are in Lena, Winslow, Orangeville, Cedarville, Freeport, Davis, Dakota, Rock City, Lake Summerset, Monroe, Clarno, Brodhead and Albany.

(2:45 PM) nwsbot: Local Storm Report by NWS MKX: Monroe Airport [Green Co, WI] awos reports TSTM WND GST of M59 MPH at 02:38 PM CDT — airport awos…sustained 30 mph with gusts to 59 mph.

(2:33 PM) nwsbot: Local Storm Report by NWS DVN: Winslow [Stephenson Co, IL] public reports HAIL of half inch size (M0.50 INCH) at 02:28 PM CDT — relayed from media.

(2:13 PM) nwsbot: Local Storm Report by NWS DVN: 3 NNE Stockton [Jo Daviess Co, IL] co-op observer reports TSTM WND GST of M64 MPH at 02:07 PM CDT –

(2:03 PM) nwsbot: Local Storm Report by NWS DVN: 3 NE Woodbine [Jo Daviess Co, IL] trained spotter reports TSTM WND DMG at 01:59 PM CDT — 2 inch diameter tree limbs down.

(1:50 PM) nwsbot: Local Storm Report by NWS DVN: NW Hanover [Jo Daviess Co, IL] trained spotter reports HAIL of penny size (M0.75 INCH) at 01:45 PM CDT — pea to penny size.

-Joe

Posted under Exactrack|HD, safety, severe weather

Severe thunderstorms and even a few tornadoes were observed across the Great Plains States on Saturday afternoon and evening.  That threat will shift a little further east on Sunday.  The National Weather Service’s Storm Prediction Center  has issued a moderate risk for severe storms in places such as Kansas City and Joplin in Missouri as well as Oklahoma City and Tulsa in Oklahoma.  These areas will deal with the threat for damaging wind, large hail, frequent lightning, torrential downpours, and possibly a tornado.

There is also a risk for severe weather further north into Minnesota and Iowa for the day Sunday.  By Sunday evening, that threat for a few stronger storms will exist here in northern Illinois and southern Wisconsin.  Hot and humid conditions are expected across the Stateline during the day with temperatures warming into the upper 80s.  Much of the first half of the day will be dry, with just a slight chance for a shower or two.  By late afternoon and early evening, a few thunderstorms will push into the area from the west.  Thunderstorms are not expected to develop in an organized pattern locally, so not all backyards will see the rain.  However, any strong storm we may see late Sunday will carry the primary threats of strong wind and large hail.  Thanks to the setting sun, solar heating (which helps to destabilize the atmosphere and ‘fuel’ thunderstorm development) will come to an end and the threat for stronger storms will decrease quickly after dark.  General showers and weakening thunderstorms will be scattered about the area overnight Sunday and fizzle out by dawn Monday.

Monday continues to have the best chance for severe thunderstorms.  Should we see enough breaks in the cloudcover leftover from Sunday night’s storms, our high temperatures may be similar to Sunday’s.  Otherwise, humid conditions and low 80s are in the forecast.  A vigorous center of low pressure will continue to slide east and shower and thunderstorm development is likely out ahead of it in our area Monday afternoon.  Some thunderstorms have the potential to take on supercell form, which includes the very slight chance for an isolated tornado.  The main concerns for Monday will be damaging straight line wind, large hail, frequent lightning and heavy rainfall.

Stay tuned to the Weather Blog and WREX.com, or you can follow the 13 Weather Authority on Facebook and Twitter for all of the latest updates regarding the chance for severe weather in northern Illinois and southern Wisconsin.  -Joe

Posted under FutureTrack, rain, safety, severe weather, Threatrack, weather, Wind

A warm front will lift through the area on Saturday, possibly sparking a thunderstorm or two. Otherwise, the weather will remain dry for most of our weekend. Perfect weather if you’re headed to the Winnebago County Fairgrounds for “Pec Thing!”

Storms on Saturday (if they even form) are expected to remain below severe limits. However, as a strong low pressure system ejects into the Plains Sunday, severe weather will become likely across Iowa. Some of these storms could get here Sunday night with the potential for some hail and damaging wind.

The main event still appears to be on target for Monday. By Monday afternoon, our atmosphere will be charged up. While the main threat will be damaging wind, some large hail and an isolated tornado won’t be ruled out. While this is still several days away, it’s important to keep tabs on the forecast this weekend so you’re ready for whatever happens Monday. The best way to get prepared is to buy a Midland Weather Radio at any area Schnuck’s store in Rockford, Cherry Valley, Loves Park, Roscoe, Janesville, or DeKalb. For less than $30, you can get a radio that will only alert you if a Tornado Warning is in YOUR county!

Posted under severe weather

All eyes will be glued to future forecast model guidance as a strong storm system ejects out of the Plains states late in the weekend into Monday.

A severe weather outbreak is possible across Southern Minnesota, Iowa, Missouri, Kansas, and Nebraska on Sunday. While forecast confidence is quite low due to future fluctuations in models’ intensity and track of this storm, by Monday, there is at least a slight chance we could be in the sweet spot for severe storm activity.

New technology from Saint Louis University allows us to look at what the models are forecasting for the next few days and compare the result to the 15 previous storm systems that were the most similar.

First, let’s check the probability of a severe weather report (left). The pink area represents more than a 60% chance of severe weather, which includes more than half of Illinois. The red area is more than a 45% chance of severe weather within 40km (30miles).

Unfortunately, the majority of our 13 county coverage area is within the highest threshold. (However, there is a spot near Peoria with a 75% probability. Amazing!)

Let’s take this one step further and examine the chances of individual severe weather reports. Keep in mind, this is not a model…rather a comparison of the forecast system to observed events.

Here is the probability of severe hail (left). While there is a chance, the worst threat will remain to our southwest. Springfield, Missouri and the area northwest of Dallas-Ft. Worth, Texas will have the highest threat for severe hail. Also note how this probability fits into the overall chance of severe (map above).

Wind probabilites jump off the charts across North-Central Illinois Monday (right). The purple area highlighted indicates a 60% chance of severe wind within 30miles of any given point. Our entire area has more than a 45% chance…which is quite significant. With a significant jet streak on top of these storms, they will have the opportunity to tug down strong wind from aloft.

Finally, let’s examine the probability for tornadoes on Monday. While at first glance (left), it doesn’t look bad, consider the fact that tornadoes are always more isolated than a wind storm or a hail storm. The highest probabilities line up with our latitude. Just a subtle change in the speed of the incoming system could put us directly in the bullseye for possible tornadoes.

NOTE: Please keep in mind that we are comparing a model forecast to the historical record. These are not necessarily forecasts and shouldn’t be looked at as such. Instead, they are maps that show a potential for severe weather. As we go through the next 1-2 days, the model accuracy will increase. As this happens, it may throw these analogs off entirely! Point being: this is four days out and the fine-tune details will change. However, if blogs like these cause just one more person to become weather-aware, it is a success in my book.

We’ll be here through the weekend and will have team coverage Monday…if we need to. -Eric

Posted under severe weather, tornado

Last night brought the country our biggest tornado outbreak of the year with a confirmed F4 that touched ground in Easter Texas near Granbury. This mile wide twister has claimed 6 lives, has left 7 people missing, has injured dozens more and has detroyed hundreds of homes. This outbreak isn’t uncommon, however after last year’s relatively tame severe weather season, it caught many people off guard. It is important to remember that May is peak season for tornadic activity, with the peak for thunderstorm activity coming in July. -Greg

Posted under Project: Tornado, severe weather, statistics, tornado, weather

The Storm Prediction Center in Norman, Oklahoma is responsible for putting out severe weather outlooks. Not only are they responsible for Severe Thunderstorm and Tornado Watches, their convective outlooks go out several days. And for several days now, there has been a consistent discussion concerning possible severe weather late this weekend and early next week.

Here is the l0ng-range outlook for Days 4-6 which highlights the most likely spots for severe weather this weekend through Monday. Day4 corresponds to Saturday, Day5 is Sunday, and Day6 is Monday.

Their words: “IT APPEARS THAT DAY 6 MAY BE THE DAY OF HIGHEST TORNADO
POTENTIAL…AS A REINFORCING MID-LEVEL SPEED MAX SHIFTS INTO THE
CENTRAL PART OF THE COUNTRY.  THE MAIN AXIS OF SEVERE WEATHER
APPEARS LIKELY TO EXTEND FROM THE IA/IL AREA SWWD ACROSS MO INTO
PARTS OF KS/OK/AR DURING THE AFTERNOON AND EVENING HOURS.”

Read the latest technical discussions by clicking here, then clicking on “Convective Outlooks.”

Posted under severe weather

Monday morning temperatures began their jump right above the freezing mark. By the time Tuesday afternoon rolls around, we will have lived through a rise of more than fifty degrees!

Thankfully for any of our farmers in the fields, the warmth will not come with showers and thunderstorms. That’s thanks to low levels of humidity. However, with time, showers and thunderstorms will become more widespread across the Upper Midwest.

On Wednesday, a cool front will stall across Central Illinois and Indiana, moving the “storm zone” south of our area. This is not a good set up for agriculture efforts downstate. But this stalled-out front will eventually move back to the north as a warm front…sparking a few thunderstorms in Northern Illinois and Southern Wisconsin Friday and Saturday.

Then, we’ll be watching the progress of a low pressure system ejecting out of the Rockies. The Storm Prediction Center already has an area highlighted for Saturday in the Central Plains (Click here to read the technical discussion.) .

Posted under cold blast, heat wave, severe weather

I had the opportunity to visit two schools on Friday for Project: Tornado 2013.  My first stop in the morning was near Poplar Grove at North Boone Upper Elementary School, where I spoke with 5th and 6th graders.  My second stop of the day brought me to Franklin Grove, where I spoke with 3rd and 4th graders at Ashton Franklin Center Elementary School.

A great question was brought up at AFC and it stumped me!  The question was: ‘How many tornadoes touch down each year in Illinois?’

After digging around for the answer, I found that 54 tornadoes occur in the Prairie State during an average year.  This climatological average was derived from all tornadoes that touched down between 1991 and 2010.  This ranks Illinois as 6 out of all 50 states for the most tornadoes per year!  Of course, this is a climatological average, so some years will see more and some years will see far less.  In 2006, 124 tornadoes were observed in Illinois.  In 2012, however, only 39 tornadoes touched down in Illinois.  Wisconsin averages 24 tornadoes per year, ranking it at 20 out of all 50 states.

Another statistic that better portrays the yearly tornado threat in Illinois is the average number of tornadoes per 10,000 square miles.  Illinois’ average is 9.7 tornadoes per 10,000 square miles and Wisconsin’s is 4.5 tornadoes per 10,000 square miles.  How big is 10,000 square miles? To give you an idea, the size of all 13 counties in the 13 WREX viewing area put together is just 7,695 square miles.

-Joe

Posted under Project: Tornado, safety, severe weather, statistics, tornado, weather