Archive for December, 2010

From Fifties to Frigid
December 31, 2010

Welcome to spring. Today’s temps made it into the low 50s across much of SE Wisconsin. Amazing end to an incredible month of weather. We did not make it to the record high of 59 set back in 1875, but it was still quite a thaw. Little if any snow is left around the area. Thankfully, we missed out on the severe weather and tornado outbreak across Illinois, Missouri, and Arkansas. At least 5 people have been killed by the 20 tornadoes being reported so far today.

Note all the red circles around St. Louis. That represents tornado reports. I called my parents and sister and was happy to hear that they are all fine. This is one of the worst outbreaks in St. Louis in at least 20 years and is likely the worst New Year’s Eve outbreak of tornadoes in U.S. history. The closest tornado reports to our area are from just outside Springfield, Illinois. There were also severe thunderstorms south of Chicago in Kankakee.

On the other of the storm, a blizzard. This is a very dynamic and strong spring-like storm. We are on the warm side of the storm because the low pressure center is staying to our west. Counter-clockwise flow around the low is bringing us warm southerly winds. That will continue until after midnight tonight. After midnight, be prepared for strong SW winds as the cold front moves through. This will bring a drastic change to our temperatures tomorrow. Here is the latest radar and surface temperature maps.

Note how the Milwaukee temperature has dropped to 46 degrees due to a SE wind. Earlier in the day, the south wind warmed us into the 50s.

We were very fortunate in our area. We missed the snow and the severe weather.

If you have plans tonight, expect drizzle and fog through about 10pm. Temps will be near 50. The cooler air will being to move in around midnight with a temperature of 40. By 2am, we’ll be close to freezing.

Have a safe and Happy New Year from Weather Watch 12.



Fog & Fifties!
December 30, 2010

It’s good to be back in Wisconsin. I hope all of you had a wonderful holiday. I had a chance to spend Christmas with my wife’s family in Minneapolis and we truly had a white Christmas. Minneapolis has received almost 50 inches of snow this season. Take a look at the snow cover on Christmas day.

27″ of snow. This was not a drift. My kids loved the snow, but my in-laws are already tired of winter. What a contrast to drive the 250 miles and see the huge differences from Minneapolis to Milwaukee. After today’s warm weather, there is little to no snow left in our area and it will almost all be gone after Friday’s temperatures reach the fifties.

So why so warm? The storm track is well to our west and north right now, allowing warm air from the Gulf of Mexico to cruise all the way into Wisconsin. Even a thunderstorm or two is possible on Friday. I hate to say it, but I can’t rule out severe weather on the last day of the year. Take a look at the RPM computer model for 9am on Friday.

Check out the strong thunderstorm just to our south across Chicago. We have a very strong jet stream that will be above our heads, great wind shear, and dew points approaching 50 degrees. Weird stuff for the last day of the year. The record high is 59 for Friday, set back in 1875. We may get close to that.

With all the melting snow and high dewpoints, a dense fog advisory has been issued by the National Weather Service until 6pm Friday. The visibilities have improved this evening with the warming temperatures. I have a feeling the advisory will be dropped early due to the lack of thick fog. The wind will pick up during the day tomorrow and temps will be quite warm. If the winds diminish, the fog may start to reform. Stay tuned.

All the snow will stay west again, this time in the Dakotas and western Minnesota. Here is a look at the snow forecast from the RPM model for tonight and Friday.

The green shades represent over a foot of snow. Sorry, snow lovers, we missed again.


Final Days of 2010
December 29, 2010

***Watch WISN 12 News for the latest weather information!***

Thank you for stopping by the Weather Watch 12 Blog!  With two days remaining in the month and no chances of snow until after the clock strikes midnight on the 31st it is safe to say this month will end with below average snowfall in Milwaukee.

Milwaukee’s total of 8.3″ will end up 3.4″ below average.  And if you would like to enjoy or get a last look at the snow before it quickly melts away, you may want to do so on Thursday.  Highs in the 40s and drizzle/rain showers are expected thru Friday.

This coming storm will not be wet for everyone, as heavy snow is likely in parts of the upper Midwest, northern Plains and throughout the Rockies.

Below is an advisory map for the entire U.S.  This map was from around 8pm on Wednesday.  The dominate color is pink, which represents Winter Storm Warnings.  The only advisory over southeast Wisconsin was an Air Quality Watch, with Dense Fog Advisories in southwest Wisconsin and over much of Iowa and Minnesota. 

Just a quick glance at this map gives a good indication of the path the storm will take.  With the wintry weather staying just west or northwest of the low track, and mainly all liquid precipitation in the ‘warm sector’ of the storm.

In southeastern Wisconsin we will stay anywhere from the upper 30s to the upper 40s from Thursday morning through Friday evening.  During this time drizzle and rain showers will be possible.  It won’t rain the entire time, and when it does it should be fairly light.

As the main low moves north a cold front will race toward our area.  As the clock strikes midnight to ring in the New Year, I expect cold air to begin sweeping across the area.

Below is the forecast surface map from the HPC for Friday at 6pm.  Notice the cold front nearing our area.  Behind the front temperatures will quickly fall into the 20s.

If you are wondering about how much rain will fall over the next 2 days here is a rough estimate from 1 computer model.  This is from the 18Z GFS.  This paints about 0.10″ to 0.50″ in our area.  Just click to enlarge.

With the expected rainfall amounts and a snow pack that is not very deep in most areas, I don’t expect many flooding issues to arise.  We’ll watch closely as if the low would track a little different a few thunderstorms may try to sneak in here and of course that could boost rainfall totals.

Overall this storm will be a big precipitation maker for some, but again it looks like we miss out on the higher rain and snow totals.

We will continue to track the system as it will impact our area and certainly bring a big change by New Year’s Day.  Snow lovers don’t lose hope yet…I see a couple of good snow chances ahead in January.

Have a great day and a Happy New Year!  I’ll post some pictures from the Rose Bowl in the coming days! 

Jeremy Nelson

Mild & Wet Days Ahead
December 28, 2010

***Watch WISN 12 News for the latest weather information!***

Thank you for stopping by the Weather Watch 12 Blog!  If you love big swings in the weather, I think you will enjoy the final days of 2010 and the start of 2011!

For snow lovers in our area, this has been a frustrating month.  Most areas in December saw anywhere from 8″ to 14″ of snow which doesn’t sound bad.  But early snows during the month were erased when rain fell in parts of the area.  And recent lake effect snows hit very isolated areas, leaving others with nothing.

That leaves us in the closing days of December with an official snow depth of just 1″ at Milwaukee’s Mitchell Airport, and of all things rain in the forecast!

The big storm will first push mild air our way, and as that begins to fall as patchy drizzle Wednesday Night, it may be freezing drizzle.  This will be a close call, as air temperatures at the surface will be right around 32.  That is why I think the best chance will be inland, and most icy spots(if they develop) forming on sidewalks, driveways, and secondary roads.

Below is the NAM precipitation forecast valid Wednesday Night at midnight.  Notice the little areas of green, which could be patchy freezing drizzle.

By Thursday the warm air will arrive in full force pushing highs into the low 40s, and insuring that all precip. will be in the form of rain or drizzle.  The main energy with the storm will not arrive until Friday.  This is when the main area of low pressure will track to our west…again.

This will likely keep our temps in the 40s, while another snowstorm will take shape for parts of Minnesota.  Below is the 18Z GFS forecast map for Friday at 6pm.  The blue line with a zero on it is the 850mb temperature.  This is the freezing line 1500 meters above the ground, and essentially the rain/snow line.  That line is well west of our viewing area.

This storm fits very well into our cycling weather pattern.  It appears that we are just about to complete the 2nd cycle of this years pattern.  Let’s check out where we are, and compare it to the November version of the storm.

Below is the 500mb(middle of the atmosphere) forecast map for this Friday.  I labeled the important features 1-6 for easy comparison.  First check out the map below for Friday.  The main features to keep an eye on is the trough that extends from the northern Plains back into the Southwest.

Now let’s rewind back to November when this part of the pattern last occurred.  Below is the 500mb archived map from November 11.  Now compare the features above, to the numbers 1-6 below.  Amazing!

With the main longterm long wave trough located over the Plains and upper Midwest, I think you can now see why storm systems continue to fall into the same place, thus bringing rounds of snow over and over again to many of the same locations.

Now that 2 complete cycles of this years pattern are almost complete, I want to share some observations.  Over the past several weeks I have done map comparisons on the pattern and discussed the likely cycle duration.  One important point about the LRC that I don’t think I have talked about enough is the variation that can occur from cycle to cycle and season to season.  My general thinking about the cycle duration for this years LRC has been around 47 days.  The map comparison above you will notice is roughly 50 days.

As the troughs and ridges cycle in the northern hemisphere, blocking or ‘bumps’ in the highway can develop that may slow down the flow or speed it up.  Not to mention the jet stream shifting due to seasonal effects.  These are several reasons why a range of days should be used.  When introducing the LRC over a year ago I was clear in this regard, saying I’ve seen durations of 42-46 days, 48-52 days, 58-62 days, etc. 

Now that two cycles are almost complete, and a wealth of information is available, I think putting a cycle range of around 46-52 days on this years pattern is reasonable.  When looking back this coming summer at each cycle, it is very likely this will average out to a duration in the upper 40s.      

The long range forecast that I did back on December 15 is still valid, and should turn out to be very close.  The one thing that will not happen is ‘warm’ weather for the Rose Bowl game in Pasadena.  My comparison was off by about 4 days, and the trough is a little farther south, makes sense it’s late December.  That means highs in the 50s on gameday.  Hopefully Wisconsin can brin home another Rose Bowl Championship!  I’ll be at the game and will share some pictures in the blog when I return!      

Have a great day!

Jeremy Nelson

My First Blog At WeatherWatch 12!
December 27, 2010

Hello Everyone!

My name is Luke Sampe, and this is my first blog entry for the WeatherWatch 12 Blog!

I usually work the morning shift during the week and on the weekends, so typically Jeremy and Mark take care of maintaining the blog. I am going to try and throw in my two cents a little more often!

First I will tell you a little about myself. I am a Wisconsinite through and through. I was literally born in a small town in northeast Wisconsin called Francis Creek. You may pass by the exit sign for it in Manitowoc county on I43 if you are heading north.

I then attended much of my school years in Two Rivers and graduated from Washington High School. After that, was when I started my first rendezvous with the city of Milwaukee. I attended UW-M in the late 90s and early 2000s. I also attended Grad School at UW-M earning both undergraduate and master’s degrees in weather forecasting.

I am married to the most supportive and loving person in my life, Amy. And a father to two amazing children, Owen and Adyson.

During my graduate work I had the amazing opportunity to study under Dr. Paul Roebber. With his guidance, I was able to complete a thesis on precipitation phase transitions. I know it sounds boring, but knowing when snow will change to rain, or rain to snow is SUPER hard to forecast. This was the exact problem with the Blizzard from a few weeks ago where Milwaukee saw only a couple inches of snow and areas just to the north has close to a foot. Obviously the rain lingered on a bit longer in the Brew City.

My television career started really by chance. Growing up I was a REALLY shy kid, so talking in front of an audience still is very intimidating to me. But TV is different, and weathercasting is almost like teaching. Making people aware of their surroundings and explaining why and how it will affect them. And talking to a camera, surprisingly, is like talking to a person. Hey I can handle that!

So when I was an undergrad, I accepted a weather internship at another TV station in town. For whatever reason, my then mentor kept pushing me and teaching me. After 4 years of prodding…I decided to try it. I applied for a Chief Meteorologist position at the NBC affiliate that serves central and northern WI…and GOT it. And the rest as they say is history.

I spent just shy of 5 years at that station, and now I find myself with the amazing opportunity to work alongside some incredibly talented people. And hopefully, settle down in the city that my wife and I absolutely love.

Well enough about me…this is a weather blog, so let’s talk weather!

Looks like we will see the first 40s of December 2010! I know some may already have cabin fever, but this is not going to be the solution. Rain will also accompany the mild temperatures along with a lot of wind. If anything, it is just going to take away the little outdoor winter fun we have around the area, and cause some localized flooding.

Here are some forecast model solutions to how this week will play out.

Above is a forecast projection at 6:00 AM Friday from the NAM model. Notice the “L” signifying the center of the storm over northern Kansas. Also the black lines are denoting isobars…the tighter they are packed the windier it will be. In this orientation, this means strong southerly winds will invade. Lastly, the temperature about 5,000 feet will be above freezing meaning the “green areas” show the precipitation would be of the liquid variety.

Above is a forecast projection at 6:00 AM Friday from the GFS model. Notice the difference in placement of the “L” more to the West with secondary “L” in the panhandle of OK, TX. Either scenario does not change our weather a whole lot, the key is the “L” is going to track to our west and keep us on the warm-side of the storm.

Above is a look at contoured surface temperatures for Friday afternoon. Notice the “L” is tracking into NW Wisconsin at this time. The strong south to southeast winds will put temps close to 45 degrees on Friday. This along with the rain showers could cause some flooding as melting snow and falling rain will try to drain into frozen creeks and rivers. This will be something that WeatherWatch 12 will be watching very closely.

Snow lovers better get out there before Thursday as outdoor winter activities will be taking a hit late in the week!


Lake Effect Snow & Week Ahead
December 26, 2010

***Watch WISN 12 News for the latest weather information!***

Thank you for stopping by the Weather Watch 12 Blog!  Bands of heavy lake effect snow buried parts of extreme eastern Racine and Kenosha counties with as much as 10″ of snow late Christmas Day!

One more band of lake effect snow is possible Sunday morning before winds shift enough to push the bands back over Lake Michigan.  Here is a look at the radar around 4am Sunday.  Notice the band of snow over the lake, this will gradually move back west and graze parts of Racine and Kenosha counties.

Lake effect snow advisories continue until Noon Sunday for Racine and Kenosha counties.  If the snow band does push back in, an additional 1″ to 4″ is possible, but as of 9am it looks like most areas will stay around 1″, or even less.  As with any lake effect event, snow totals have varied greatly across the area.  Here is a look at totals from lakeshore counties thru 6am Sunday.

  • Kenosha  6″-10″
  • Racine  5.5″
  • Franksville  4.0″
  • Cudahy  1.1″
  • Milwaukee Mitchell Airport  0.6″
  • WISN 12  Dusting

Lake effect snow bands can produce some incredible snowfall rates and blinding snow.  That is what occurred last night as a heavy band of snow blanketed parts of Racine and Kenosha counties.

The image below from the NWS shows estimated one hour snowfall accumulations from 923 to 1023 pm CST.   Green areas are 1+” of snow per hour, brown 2+” per hour, and red 3+” per hour snowfall rates! 

If you have a snow total or pictures of the snow please send them to us!  Pictures can be emailed to and totals can be dropped off in the comments section of the blog. 

Moving forward this week, quiet weather will hold through Wednesday.  After that the much advertised New Year’s storm will head into the nation’s mid-section.  As of this writing it appears that mild air will surge north, placing southeastern Wisconsin in the warmer part of the storm.  This would mean a chance of rain, before colder air changes any moisture over to snow.

Below is a total precipitation forecast from the 6Z GFS computer model.  This would indicate around 0.50″ to 1.00″ of precipitation, most coming in the form of rain.  Just click on the image to enlarge.


We will continue to monitor the trends and have the updated forecasts on WISN 12 News!

Have a great day!

Jeremy Nelson

Snow Totals & Weekend Snow Showers
December 24, 2010

***Merry Christmas from Weather Watch 12!***

Thank you for spending part of your holiday with us on the Weather Watch 12 Blog!  Pockets of light snow will continue to push across southeastern Wisconsin into very early Christmas morning.  It should be a pretty ride across our area for Santa!

Snow totals as of 5pm Friday fell into the trace to 2″ range in our area. 

  • Jefferson  2.0″
  • Eagle  1.6″
  • Beaver Dam  1.5″
  • Kenosha  0.5″
  • Milwaukee  Trace

Please drop off your snow totals to the comments section of the blog.  I will be including a list on our WISN 12 newscasts.  I will continue to update the list all evening.

Below is a radar image from around 4:30pm Friday.  The colors showing up indicate light snow and flurries.  Also notice a few holes in the radar where no snow was falling.

For a live look at our interactive radar just click below.  Keep in mind you can zoom the radar right down to where you live!

By Saturday and Sunday winds will turn to the north, and at times a north-northeast direction.  With colder air spilling over Lake Michigan, lake-effect snow showers will be possible in spots.  This doesn’t look like a great set-up for snow in Milwaukee, but it does look like some snow is possible.

The best bet for snow looks like later Saturday and into Sunday.  Remember lake-effect snow bands typically aren’t very wide, and can bring a wide range of snow totals to areas they hit, or miss! 

Below is a snowfall forecast for this weekend.  Notice the light blue shade hugging the shoreline in parts of Milwaukee, Racine, and Kenosha counties.  This band represents 2″ of snow.  I would see a few spots getting an inch or two of lake-effect snow this weekend, and maybe a hair more if a band would be persistent.

A much bigger weather maker will move in our direction to end 2010.  This could bring rain, a mix, or snow to our region.  Remember, we highlighted this timeframe as one that should produce a storm.  That prediction was posted in the long range forecast made on December 15.  Look for updates on that storm in the blog in the coming days!

Have a happy holiday!

Jeremy Nelson

Christmas Eve Snow Chances
December 23, 2010

***Watch WISN 12 News for the latest snowfall forecast!***

Thank you for stopping by the Weather Watch 12 Blog!  If you put snow on your Christmas wish list this year, your present will arrive a few hours early on Friday.  It may look like a snow globe or something out of a movie Friday evening as light snow should be falling across much of southeast Wisconsin.

The question now is when will the snow start, and how much is expected? 

Let’s start by looking at the locations that are under Winter Weather Advisories for Friday.  Only a small part of southwest Wisconsin is included in the advisory.  No counties in the WISN 12 viewing area are included as of this writing.

The snow will spread from west to east across southern Wisconsin on Friday.  It should reach southeast Wisconsin by afternoon, and around Milwaukee by say 2-5pm.  The snow will be light, but should fall for the better part of Friday evening and into the night.

Waking up on Christmas morning there should be a fresh coating of snow in most areas.  Let’s look at two snowfall forecasts.  This by no means will be a major storm for our area.

The first snow forecast is from our in-house computer model.  This shows generally an inch of snow around Milwaukee with a little more to the south and west.  Heavy snow could blanket parts of Iowa…again.  

The next snow forecast is the one that I showed on WISN 12 News on Thursday.  Not much different than the map above, but hopefully it provides more detail.  Keep in mind this snow forecast runs from Friday through early Saturday morning.  Just click to enlarge. 


It appears this will be either a beautiful snow, or a ‘nuisance’ snow depending on your perspective.  As we move into the final week of 2010, as discussed in the long range forecast over a week ago, I expect a major storm to develop in the nation’s mid-section.

Lots of questions surround this potential storm a week out, but it does look like it will be strong, and could bring our area rain, a mix, or snow.  Below is the surface forecast map for December 31st.  The map below is from the 18Z GFS.


While the strength and track will shift around in the coming days, I expect this to play a major role in our weather to close 2010.

If you have any questions about the snow for Friday, just post your thoughts to the comments section.  Have a Merry Christmas!

Jeremy Nelson

Weekend Lake Effect Snow Chances
December 22, 2010

***Watch WISN 12 News for the latest on the holiday forecast!***

Thank you for stopping by the Weather Watch 12 Blog!  Overall the weather looks pretty quiet the next couple of days in our area.  Tuesday’s snow on top of the snow that was in place should insure almost all areas will see a white Christmas again this year.

If you remember back to last year, a large storm system moved across the Midwest.  Milwaukee saw nearly 1.50″ of rain on December 24-25, and only 0.1″ of snow!  Still it was a white Christmas officially with 2″ of snow on the ground to start the day at Mitchell Airport.

Below is the snow depth on Christmas Day over the past 11 years in Milwaukee.

  • 2009  2″
  • 2008  13″
  • 2007  1″
  • 2006  0
  • 2005  2″
  • 2004  0
  • 2003  Trace
  • 2002  0
  • 2001  Trace
  • 2000  25″
  • 1999  1″

A few things stand out.  First, 5 of the 11 years had either no snow or a trace on the ground.  And the big winner was the record setting December of 2000 with a snow depth of 25″!

While I doubt we add much to the snow depth this year before the morning of December 25, let’s discuss a couple of snow chances.

The first will move our way on Christmas Eve Day.  With some dry air in place and the weak upper level disturbance to our south, I expect much of the moisture to stay either south or west of our area.  However, some pockets of light snow or flurries are possible.

Here is a look at the 12Z GFS forecast for 6pm Friday.  We are just on the edge of the snow showers and flurries.  Some light snow accumulation is possible, especially where any lake enhancement occurs.

As that disturbance slides by, high pressure will strengthen to our north over Canada.  This high and the clockwise winds around it will do 2 things.  First it will draw in colder air on northerly winds.  Second, as the winds turn more northeasterly, the chance for lake effect snow will increase as the coming weekend progresses.  This is still a long way out to get too excited about a mesoscale event like lake effect snow.  But at least the chance is there.

Below is the 12Z GFS surface forecast for this coming Sunday afternoon.  This indicates a northeast wind and some snow showers, especially closer to Lake Michigan.  The green color represents precipitation, in this case lake effect snow.   

We will continue to monitor this as the weekend nears.  Keep in mind a slight wind shift could mean no snow, or a prolonged northeast wind could mean enough snow to shovel in spots.  Lake effect snow is always a challenge to forecast, but let’s keep an eye on this chance as the weekend nears.

For the latest updates make sure to watch WISN 12 News at 5, 6, & 10pm!

Have a great day!

Jeremy Nelson

Snow Totals and The Pattern Ahead
December 21, 2010

***Watch WISN 12 News for the latest weather information!***

Thank you for stopping by the Weather Watch 12 Blog!  Light snow swept through southeastern Wisconsin Monday evening into early Tuesday.  This snow was more of a ‘nuisance’ than anything.  Thank you to everyone who posted totals to our Facebook page at WeatherWatch 12!  Don’t forget you can always leave totals in the comments section of the blog too. 

Here is a look at totals around our area!

  • Burlington  2.9″
  • Brookfield  2.8″
  • New Berlin  2.0″
  • Franksville  2.0″
  • Glendale  2.0″
  • Fort Atkinson  1.9″
  • Racine  1.5″
  • Random Lake  1.0″
  • Milwaukee  1.0″
  • Slinger  1.0″
  • Sheboygan(Lakeshore) <1″


For the rest of Tuesday a few flurries or pockets of drizzle are possible as this weak storm departs.  The question now turns to what lies ahead moving into the Christmas holiday.

If you follow the blog you know that I use a weather pattern theory called the LRC, or Lezak’s Recurring Cycle.  This weather pattern theory states that once the weather pattern sets up in the Fall, it begins to cycle.  The pattern is unique each year, and once again the pattern is cycling!  This year’s cycle length is around 46-48 days.

Last week in the blog we took a look at the long range forecast thru the end of January, just scroll down a few blog entries and check it out!

One of the big stories around the country right now is the heavy rain and snow in the West.  The rain and snow in that part of the country will likely hang arond another day or two.  Below is the 500mb forecast map from the NAM computer model, just click to enlarge.  Keep in mind the 500mb level is the middle of the atmosphere.


Now let’s look back roughly 46 days to November 6.  Again an upper low is present near southern California.  Also present is a ridge in the Plains, and a trough in the East.  The main features in this cycling weather pattern line up very close to the forecast map above for December 22. 

Now a few people may be wondering about what the pattern looks like around Christmas.  When I did the long range forecast last week based on the LRC, I said that I do not expect a major storm for our area on the 24th or 25th.  That is something I still believe.  But could there be light snow?

Below is the 500mb forecast map from the NAM for December 24.  The main feature on this map to focus on is the small upper low over the Plains.  If we are going to see snow on Christmas Eve, this would be the feature that would produce it. 

If we look back 46 days to November 8, this feature tracked from southern California into the northern Plains.  The feature on the map below from November 8 I’m referring to is over the eastern Dakotas and western Minnesota.  The rest of the features are also present.  The trough in the West was farther east back in November due to the ridge being stronger in the Pacific.  Overall though this is another great example of this year’s cycling weather pattern. 

We’ll keep an eye on that chance of light snow around the 24th, but certainly the models are trending this lower each day.

As discussed in the long range foreast I issued last week, I’m still expecting a larger storm to take shape to close the month, and that will be followed by another blast of cold air!  If you love wintry weather, get ready for a pretty exciting January!

Have a great day!

Jeremy Nelson