Wildlife and Weather

Fireflies!

Photo: Flickr / Dick ToddIt’s midsummer, which means it’s the perfect time to encounter the iconic night flying insect: the firefly. The best way to experience fireflies is to turn off the TV, put away the video games and get outside! Learn how to create a firefly habitat, how to watch fireflies and how to get the whole family involved.

Did you know?

  • Fireflies are actually beetles, not flies.  Lightening bug, their other common name, is also inaccurate since bugs are their own order of insects, distinct from beetles.
  • Fireflies create their “fire” by mixing oxygen with a chemical called luciferin in their abdomen, which creates light without any heat.  Each species has a unique flash pattern, which they use to attract mates.
  • Firefly larvae are carnivorous, feeding on slugs, worms and other soft-bodied invertebrates around streams and ponds.
  • As adults, some firefly species feed on nectar, and some don’t feed at all, but females in the genus Photuris mimic the flashes of females in the genus Photinus.  When a Photinus male approaches looking for a mate, the female Photuris devours him!
  • In the U.S. almost all firefly species are found east of the Mississippi, which gives folks from the western states an excuse to vacation back east!
  • Development of fields, woods and wetland habitats that fireflies need, overuse of pesticides and light pollution all have negative impacts on firefly populations.

Climate and Wildlife

Here’s a roundup of some of the recent news and science about wildlife and climate change.

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Posted under wildlife

This post was written by Eric Sorensen on July 31, 2009

winter_alert5

At 4:50, the Storm Prediction Center issued an updated mesoscale discussion saying a Tornado Watch will not be needed. Storms leftover will have the small chance to produce a few funnels but long-lived tornadoes are not expected. Update coming on 13News@5.  http://www.spc.noaa.gov/products/md/md1726.html

(4:23:16 PM) nwsbot: LOT: 2 N Capron [Boone Co, IL] trained spotter reports FUNNEL CLOUD at 04:22 PM CDT — funnel cloud descending. 1900 block hunter road

(4:26:55 PM) nwsbot: LOT: 2 N Capron [Boone Co, IL] trained spotter reports TORNADO at 04:26 PM CDT — circulation on the ground with dust, 73 mph winds. at boone school road and capron road
(4:28:53 PM) media-mike.tamas entered the room.
(4:31:52 PM) nwsbot: LOT issues Tornado Warning for McHenry [IL] till 5:15 PM CDT …* AT 422 PM…A TRAINED SPOTTER REPORTED A TORNADO NEAR CAPRON ROAD AND HUNTER ROAD. AT 430 PM CDT…RADAR CONTINUED TO INDICATE STRONG ROTATION IN THIS THUNDERSTORM 13 MILES WEST OF WOODSTOCK…MOVING EAST AT 30 MPH.
(4:33:53 PM) nwsbot: LOT: Capron [Boone Co, IL] trained spotter reports TORNADO at 04:30 PM CDT — tree debries in air. heavy rain, nickle size hail. 82 mph winds e-se course at capron road and 173
(4:37:05 PM) nwsbot: LOT cancels Tornado Warning for Boone [IL]
(4:37:05 PM) nwsbot: LOT continues Tornado Warning for McHenry [IL] till 5:15 PM CDT …AT 426 PM…TRAINED WEATHER SPOTTERS REPORTED A TORNADO ON THE NORTH SIDE OF CAPRON NEAR HUNTER ROAD AND CAPRON ROAD. THE TORNADO WAS LOCATED 2 MILES SOUTH OF HARVARD…MOVING EAST AT 20 MPH.

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Posted under tornado

This post was written by Eric Sorensen on July 30, 2009

These graphics speak for themselves

pacnwweather_story11weather_story23

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Posted under cold blast, heat wave, weather

This post was written by Eric Sorensen on July 29, 2009

Friday and Monday hailstorms have scarred the landscape

Special thanks to the Milwaukee Weather Service forecast office for picking up on this one. Evidently, Friday (and to a lesser extent Monday’s) hailstorms have ripped up and destroyed so much vegetation that they are being observed on satellites! Clouds are even forming more efficiently in these locations because the bare ground heats up more efficiently than areas of thick vegetation.

Here is the complete article:

On Friday July 24, 2009, multiple significant hail storms moved southeastward across northeast Iowa, southwest Wisconsin, and northwest Illinois. These hail storms produced extremely large hail, and copious amounts of hail, which led to some concentrated swaths of damage to vegetation. In some areas, most of the crops were severely damaged or destroyed. For a complete write-up on the situation, click here.

With a relatively clear day today, some of the scarring is visible on satellite images. First, the MODIS Vegetation Index which is a 1km resolution product designed to pick up on areas of greenness in the vegetation:

A minimum of about 28% greenness is evident just south-southeast of Belmont, which is not surprising given that is where some of the worst crop damage was observed. Corn stalks were completely stripped and sheared off to a height of less than 2 feet. These damaged areas of vegetation now absorb more radiation from the sun, thereby allowing the surface to heat faster. This phenomenon is evident in the MODIS 250m resolution satellite image from below. Cumulus clouds fired in greater abundance on the Wisconsin hail swaths, which makes them less distinguishable than the Iowa hail swath.

If cumulus clouds had not developed in such great abundance over the Wisconsin swaths, the damage evident in the browning of the surface in Iowa would likely appear along the swaths in Wisconsin as well.

In western Clayton County, the surface skin temperature (temperature of the Earth’s surface, rather than the air temperature), as estimated by MODIS 1km resolution satellite imagery, had a differential of about 22 degrees between the hail swath and the green vegetation remaining outside of the swath at 11:58 AM CDT. In northwest Lafayette County, the differential was around 15 degrees. This proves that the areas with vegetation damaged by hail tend to heat up much more quickly than surrounding areas, and it also explains why the diurnal cumulus would develop there first.

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Posted under severe weather, space

This post was written by Eric Sorensen on July 29, 2009

Our summer flipbooks are sad

summer09Our weather computers are chalked-full with “flipbooks” which are those fancy, colorful graphics that help us tell the weather story each day.

However, these haven’t been used to describe ONE day this summer! What are some weather words, phrases, or sentences that you’d usually hear this time of year…but haven’t so far.

I’ll start! How about “So hot you could fry an egg on the sidewalk!” -ES

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Posted under weather

This post was written by Eric Sorensen on July 28, 2009

Push REFRESH on your browser for the latest reports and information. winter_alert3

(11:06:10 PM) nwsbot: LOT issues High Wind Warning for Lake, McHenry [IL] till Jul 28, 2:00 AM CDT

Storms winding down as of 11:00pm Monday night. Flash Flood Warnings will continue for much of the night for Carroll, Whiteside, Ogle, and Lee Counties. Do not drive across a flooded roadway. Meteorologist Justin Gehrts will have the latest weather on 13News Today beginning at 5AM. -ES

(10:53:53 PM)
nwsbot: DVN: Mount Carroll [Carroll Co, IL] trained spotter reports HEAVY RAIN of E1.61 INCH at 10:51 PM CDT — total since 940 pm. still raining.

(10:34:22 PM)
nwsbot: DVN: Stockton [Jo Daviess Co, IL] broadcast media reports HEAVY RAIN of M1.50 INCH at 10:30 PM CDT — relayed report from media. rain has stopped.

(10:34:55 PM)
nwsbot: LOT: Oregon [Ogle Co, IL] broadcast media reports TSTM WND DMG at 10:05 PM CDT — eight inch diameter tree limb fell onto a house on 4th street causing minor damage. time estimated.

(10:31:56 PM) nwsbot: LOT: 5 Nw Polo [Ogle Co, IL] co-op observer reports HEAVY RAIN of M0.95 INCH at 10:25 PM CDT — rainfall in 45 minutes. still raining.

(10:29:28 PM)
nwsbot: LOT: Dixon [Lee Co, IL] broadcast media reports HAIL of half inch size (E0.50 INCH) at 10:25 PM CDT — pea to marble size hail.

(10:26:46 PM)
nwsbot: DVN issues Flash Flood Warning for Clinton [IA] and Whiteside [IL] till Jul 28, 4:30 AM CDT

(10:17:06 PM)
nwsbot: DVN: Mount Carroll [Carroll Co, IL] trained spotter reports HEAVY RAIN of M1.04 INCH at 10:14 PM CDT — rainfall total since 940 pm.

(9:55:40 PM)
nwsbot: LOT: 5 Nw Polo [Ogle Co, IL] co-op observer reports HAIL of half inch size (E0.50 INCH) at 09:49 PM CDT — dime size hail. very heavy rainfall. estimated winds at 40 to 45 mph.

(9:53:53 PM)
nwsbot: DVN: Freeport [Stephenson Co, IL] trained spotter reports HEAVY RAIN of M1.25 INCH at 09:55 PM CDT — total since 845 pm. still raining.

(9:49:21 PM)
nwsbot: DVN expires Severe Thunderstorm Warning for Jo Daviess, Stephenson [IL]

(9:47:31 PM)
nwsbot: DVN issues Flash Flood Warning for Jackson [IA] and Carroll, Jo Daviess, Stephenson [IL] till Jul 28, 3:45 AM CDT

(9:46:07 PM) nwsbot: DVN: 1 N Savanna [Carroll Co, IL] law enforcement reports HAIL of penny size (E0.75 INCH) at 09:40 PM CDT — also reported heavy rain.
(9:47:22 PM) nwsbot: DVN: 1 Ene Shannon [Carroll Co, IL] trained spotter reports TSTM WND GST of E60 MPH at 09:44 PM CDT — estimated 50 to 60 mph.

(9:46:07 PM)
nwsbot: DVN: 1 N Savanna [Carroll Co, IL] law enforcement reports HAIL of penny size (E0.75 INCH) at 09:40 PM CDT — also reported heavy rain.

(9:38:27 PM)
nwsbot: DVN: Freeport [Stephenson Co, IL] broadcast media reports TSTM WND GST of E60 MPH at 09:20 PM CDT — relayed by media. viewer estimated 50 to 60 mph wind gust.

(9:27:18 PM)
nwsbot: DVN: 3 Nne Stockton [Jo Daviess Co, IL] co-op observer reports HEAVY RAIN of M0.87 INCH at 09:15 PM CDT — 45 minute total. rain has ended.

(9:15:54 PM)
nwsbot: DVN issues Severe Thunderstorm Warning for Carroll, Whiteside [IL] till 10:15 PM CDT

(9:13:26 PM) nwsbot: LOT issues Severe Thunderstorm Warning for Lee, Ogle [IL] till 10:15 PM CDT

(9:03:34 PM)
nwsbot: DVN: 3 Nw Stockton [Jo Daviess Co, IL] trained spotter reports TSTM WND GST of E60 MPH at 08:55 PM CDT — spotter estimated 50 to 60 mph.

(8:46:05 PM) nwsbot: MKX cancels Severe Thunderstorm Warning for Green, Lafayette [WI]

(8:25:38 PM) nwsbot: DVN issues Severe Thunderstorm Warning for Jo Daviess, Stephenson [IL] till 10:00 PM CDT

(8:13:48 PM) nwsbot: MKX issues Severe Thunderstorm Warning for Green, Lafayette [WI] till 9:15 PM CDT

7:50pm – From the National Weather Service in the Quad Cities concerning the storm scraping into northern Jo Daviess and Stephenson Co.: monitoring sw WI storms to psbly get in nw IL.

7:30pm – A Tornado Warning will likely be needed for Green Co., Wisconsin within the next 15-20 minutes. Spotters were observing a funnel cloud in Lafayette Co. This storm is moving southeast at 35mph and will enter Green County by the top of the hour. This storm, on its current track and intensity (should that not change), will then proceed toward northern Stephenson by 8:30pm. -ES

6:45pm – Storm Prediction Center issues Mesoscale Discussion regarding tornadic storms in Southern Wisconsin…and possible watch for Northern Illinois. (6:44:28 PM) nwsbot: Storm Prediction Center issues Mesoscale Discussion #1695 (View text)

6:45pm – Indexes that are used to forecast severe weather and tornadoes indicate that the storms will continue on their current path and with current intensities as they move into Green County by 7:05pm. Review severe weather precautions and be observant for changing weather conditions. -ES

tornadicstorms1

6:15pm – Tornadic thunderstorms continue to race through southwestern Wisconsin on a trajectory that places them in Green Co., WI by 7:05pm. These storms have had a history of producing damaging wind gusts, along with unconfirmed tornadoes. If you live northwest of Rockford, be mindful of rapidly changing weather within the next 1-2 hours. Should these storms hold together they will arrive in the Rockford metro by 8:30pm

this evening. I will be consulting with the National Weather Service about a new watch that will likely be needed for parts of Northern Illinois within the next few hours. Once the sun sets around 8:20pm this evening we will lose some instability and it remains to be seen whether these tornadic storms will keep their intensity by the time they reach our immediate area. Updates here on the blog as we learn more. -ES

(2:40:07 PM) nwsbot: MKX issues Severe Thunderstorm Watch for Columbia, Dane, Dodge, Fond du Lac, Green, Green Lake, Iowa, Jefferson, Kenosha, Lafayette, Marquette, Milwaukee, Ozaukee, Racine, Rock, Sauk, Sheboygan, Walworth, Washington, Waukesha [WI] till 9:00 PM CDT

2:30pm – A Severe Thunderstorm Watch will likely be issued for Southern Wisconsin until 9pm. We’ll know the exact counties within the next few minutes. -ES

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Posted under severe weather, tornado

This post was written by Eric Sorensen on July 27, 2009

climate_authority32

Watch where your information comes from. That’s the bottom line so I thought I’d get that off right away so I didn’t waste your time. Evidently George Will, a Washington insider, sparked a firestorm by completely denouncing global warming. I’ll be upfront and admit I didn’t read his column. One reason? I don’t care what a Washington insider thinks is going on when it comes to climate change. However, I did read a point-counterpoint to his article and I’d like you too.

This article comes from examiner.com which looks very much like a news website. It is not. Anyone can become “publishers” on their website so again, be careful where the information you’re reading is coming from. Back to the point-counterpoint of George Will’s column. Tom Fuller has some great points in his article which you should read by clicking here.

Never before have I read an article that so closely expresses my belief of global climate change and the curiosity that comes with it. Sure, we know the earth’s climate is in flux. We know the earth has been warmer and cooler in its past. Biggest question that needs to be answered is this: Did we have an influence on the significant global warming in the 20th century and if so, what do we do in the future to secure that it doesn’t continue to happen/happen again?

As a country and society we need to come together and quit calling the other side’s beliefs absurd or outlandish. Nail on head Mister Fuller.

Because I am in an intense search for scientific reasons behind global climate change I didn’t read any of his blog comments. I am not terribly concerned with what John Q. Public comments about on a national website. However, I welcome yours. What did you think of the article? More importantly, what questions do you think need to be answered and how do you propose we do this?

Happy Monday everyone!

Eric Sorensen

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Posted under 13 Climate Authority

This post was written by Eric Sorensen on July 26, 2009

Push your browsers REFRESH button for the latest reports.

winter_alert1

(7/24/2009 9:49:39 PM) nwsbot: MKX: 2 Se Delavan [Walworth Co, WI] public reports NON-TSTM WND GST of M46 MPH at 07:15 PM CDT — measured on a privately owned weather station near delavan lake. wind gusts occurred due to a wake low.

(7/24/2009 8:46:23 PM) nwsbot: MKX: Beloit [Rock Co, WI] law enforcement reports NON-TSTM WND DMG at 08:15 PM CDT — from 745 pm to 815 pm…strong winds and tree damage reported in several locations in the beloit area. the wind was due to a wake low.

(10:22:43 PM) nwsbot: DVN: Sterling [Whiteside Co, IL] emergency mngr reports FLASH FLOOD at 09:40 PM CDT — a half mile stretch of route 40 in town is closed due to water over the road. water is 4-5 inches deep in places.

(9:58:45 PM) nwsbot: LOT: 5 Nw Polo [Ogle Co, IL] co-op observer reports HEAVY RAIN of M1.19 INCH at 09:55 PM CDT —
(9:18:54 PM) nwsbot: LOT: Winnebago [Winnebago Co, IL] broadcast media reports TSTM WND GST of E60 MPH at 09:10 PM CDT — reported by wrex tv.

(7/24/2009 8:13:14 PM) nwsbot: MKX: 4 S Janesville [Rock Co, WI] awos reports NON-TSTM WND GST of M44.00 MPH at 07:45 PM CDT — measured from the janesville airport due to a wake low

(7/24/2009 8:07:28 PM) nwsbot: DVN: 1 E Galena [Jo Daviess Co, IL] law enforcement reports TSTM WND DMG at 06:55 PM CDT — *** 1 inj *** semi truck blown over on top of passenger car at hwy 20 and mount hope rd resulting in 1 injury. also trees down in the same area.

(7:39:34 PM)
nwsbot: DVN issues Severe Thunderstorm Warning for Clinton, Jackson [IA] and Carroll, Rock Island, Whiteside [IL] till 8:45 PM CDT

(7:11:42 PM)
nwsbot: LOT issues Severe Thunderstorm Warning for Lee, Ogle [IL] till 8:15 PM CDT

(7:08:08 PM) nwsbot: MKX cancels Tornado Watch for Green, Iowa, Lafayette [WI]

(7:08:53 PM)
nwsbot: DVN: Elizabeth [Jo Daviess Co, IL] public reports HAIL of nickel size (M0.88 INCH) at 07:07 PM CDT — along with heavy rain.

(7:01:42 PM)
nwsbot: DVN: Council Hill [Jo Daviess Co, IL] trained spotter reports HAIL of golf ball size (M1.75 INCH) at 06:49 PM CDT — ping pong to golf ball size hail.

(6:53:35 PM) nwsbot: DVN: 3 Wsw Freeport [Stephenson Co, IL] trained spotter reports TSTM WND DMG at 06:51 PM CDT — 4 to 6 inch tree limbs down 1.10 inches of rain in 15 minutes.

(6:52:38 PM) nwsbot: DVN: 5 Sse Council Hill [Jo Daviess Co, IL] trained spotter reports HEAVY RAIN of E0.50 INCH at 06:52 PM CDT — in the last 20 minutes

(6:47:49 PM) nwsbot: DVN: Scales Mound [Jo Daviess Co, IL] law enforcement reports FUNNEL CLOUD at 06:42 PM CDT — rapid rotation over town reported by fire department.

(6:26:23 PM) nwsbot: DVN: 2 N Pearl City [Stephenson Co, IL] trained spotter reports HAIL of nickel size (E0.88 INCH) at 06:25 PM CDT —

(6:19:08 PM) nwsbot: DVN issues Severe Thunderstorm Warning for Dubuque, Jackson [IA] and Jo Daviess [IL] till 7:30 PM CDT

(6:10:53 PM) nwsbot: LOT issues Severe Thunderstorm Warning for Ogle [IL] till 7:15 PM CDT
(6:22:24 PM) nwsbot: LOT continues Severe Thunderstorm Warning for Ogle [IL] till 7:15 PM CDT

(6:11:00 PM) nwsbot: DVN: 4 Ene Stockton [Jo Daviess Co, IL] amateur radio reports HAIL of golf ball size (M1.75 INCH) at 06:04 PM CDT — measured winds of 35 mph.
(6:11:01 PM) nwsbot: DVN: 3 S Stockton [Jo Daviess Co, IL] public reports HAIL of golf ball size (M1.75 INCH) at 06:09 PM CDT —

(6:09:24 PM) nwsbot: DVN: Stockton [Jo Daviess Co, IL] co-op observer reports HAIL of egg size (M2.00 INCH) at 06:07 PM CDT — mostly golfball hail…with a few up to 2 inches.

(6:02:06 PM) nwsbot: DVN: Apple River [Jo Daviess Co, IL] amateur radio reports HAIL of golf ball size (M1.75 INCH) at 05:52 PM CDT —
(6:02:06 PM) nwsbot: DVN: 2 N Stockton [Jo Daviess Co, IL] amateur radio reports HAIL of tennis ball size (M2.50 INCH) at 05:58 PM CDT —

(5:43:58 PM) nwsbot: DVN: 2 E Scales Mound [Jo Daviess Co, IL] law enforcement reports HAIL of golf ball size (M1.75 INCH) at 05:38 PM CDT — half dollar to golfball size hail.

(5:15:21 PM) nwsbot: DVN issues Severe Thunderstorm Warning for Jo Daviess, Stephenson [IL] till 6:15 PM CDT

(4:57:58 PM) nwsbot: Storm Prediction Center issues TORNADO watch till 04:00 UTC , new watch replaces WW 616, WW 617 (Watch Quickview)

(4:36:10 PM) nwsbot: ARX: Stitzer [Grant Co, WI] emergency mngr reports HAIL of golf ball size (M1.75 INCH) at 04:33 PM CDT —

(4:36:20 PM)
nwsbot: MKX continues Severe Thunderstorm Warning for Iowa, Lafayette [WI] till 6:00 PM CDT

4:27pm – Our live weatherblog chat is coming soon…as is a new weather watch.
This report came in from the supercell in Iowa earlier this afternoon. Wow!

3 Nw Oneida [Delaware Co, IA] public reports HAIL of tennis ball size (M2.50 INCH) at 02:29 PM CDT — copious amounts of tennis ball size hail. car windshield cracked. delayed report.

mcd1661

4:00pm – Updated Mesoscale Discussion from the Storm Prediction Center for our area: http://www.s

pc.noaa.gov/products/md/md1661.html Storms over southwestern Wisconsin and northeastern Iowa are having little trouble developing (even under cloudy skies). May see some sort of weather watch for the area highlighted by 5pm this evening in advance of these storms. -ES

3:30pm – The Storm Prediction Center has taken Southern Wisconsin out of the slight risk of severe for this evening. I think that may have been premature as the atmosphere is recovering nicely along the cold front from Eau Claire to Mason City. Strong storms will be possible in the evening hours after a few hours of rain this afternoon. -ES

scatterspike

3:10pm – Davenport NWS Doppler radar’s latest scans are showing a nice scatter spike (or hail spike). This occurs when the radar beam enters the storm and bounces off of very large hail within the hail core. Radars work because  radiation (or radar beam) is sent out from the radar…but it’s not until the radiation returns to the radar, that we know what’s going on. When there’s a significant thunderstorm with large hail like this, the beam is bouncing off of very large hailstones within the core. Because of this, it takes longer for the beam to make it back to the radar site because it’s been scattering. This time delay causes the reflectivity (colors) to be plotted further back than where they originally occured.

Backscatter or hail spikes only occur when there’s monster hail in that storm. It’s quite a distance (as the crow flies) from DVN’s radar so as the storm moves toward the radar site, the beam will be lower in the storm and the spike should go away. -ES

helicity

2:46pm – Here is a look at the helicity analysis for the area right now. Helicity is basically the tendency for a corkscrew motion in the atmosphere from bottom to top. Obviously, higher amounts of helicity indicate a higher chance for severe. As expected, this is centered over Rochester, Minnesota and La Crosse, Wisconsin this afternoon and will stay northwest of the area through the event.

2:41pm – Rain and embedded thunderstorms will affect the region from 3-6pm this afternoon. These storms will not reach severe thresholds. However there remains a slight risk of severe storms with a cold frontal passage between 8pm and midnight tongiht. -ES

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Posted under severe weather

This post was written by Eric Sorensen on July 24, 2009

winter_alert

6:20pm – Still a few storms west of Madison that will work south into the viewing area this evening. Storm chance around 30% and will go away completely once the sun goes over the horizon. -ES

5:35pm – Storms moving through Rockford have not produced anything more than pea-sized hail. Some gusty wind is possible in northern Ogle and DeKalb Co by 6:15pm…perhaps up to 40mph. -ES

(4:38:08 PM) nws-alex.lamers: we’re keeping an eye on a developing mesocyclone in that rock county cell. it doesn’t look strong enough for a tornado right now, but the rotation is there, especially in the mid levels

(4:37:14 PM) nwsbot: MKX continues Severe Thunderstorm Warning for Rock, Walworth [WI] till 5:15 PM CDT

(2:30:28 PM) nwsbot: LOT cancels Severe Thunderstorm Warning for De Kalb, Kane [IL]

(2:10:21 PM) nwsbot: LOT cancels Severe Thunderstorm Warning for Boone [IL]
(2:10:21 PM) nwsbot: LOT continues Severe Thunderstorm Warning for De Kalb, Kane [IL] till 3:00 PM CDT

(7/23/2009 1:20:19 PM) nwsbot: LOT: Rockton [Winnebago Co, IL] trained spotter reports HAIL of half inch size (E0.50 INCH) at 01:19 PM CDT — heavy hail falling. also winds gusting to around 45 mph.

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Posted under severe weather

This post was written by Eric Sorensen on July 23, 2009

Severe weather outbreak possible Friday evening

severeTime to hoist a red flag for the cold front arriving Friday night. Potential instability is through the roof as this system gets to our area. Low pressure will be in the developing stages as it enters Iowa during the afternoon. Models are then hinting that the low will shift northward into Lake Superior. This movement will cause the front to become negatively tilted. (Normally fronts extend southwestward from low pressure. Negatively tilted fronts start at the low and move southeast. These fronts increase wind shear and often times are signals for severe weather). Caveat: a warm front lifts through Northern Illinois and Southern Wisconsin during the morning hours. Should showers/storms form along this, their debris clouds will prevent us from seeing surface heating. However this is not the anticipated scenario and plenty of heating will cause sufficient instability. The front, along with a wave of low pressure, will cause storms to form over Iowa during the afternoon and progress eastward. Should all things come together there would be a threat of tornadoes over the region. Even though the Storm Prediction Center is putting us in a slight risk with the overnight package, will go ahead and bump that up a bit as the morning and afternoon models are going so gang busters with this Friday front. -ES

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Posted under severe weather, tornado

This post was written by Eric Sorensen on July 22, 2009