Archive for January, 2010

Wimpy Storm Awaits
January 31, 2010

Hello, all. I am sure you have all enjoyed Jeremy’s blogs for the last five days and learning more about the LRC. I am learning along with the rest of you, but giving myself a full winter season before weighing in. I will say it has performed pretty well so far this winter. Better than I ever would have thought for a relatively unknown theory. If you have no idea what I am talking about, take a look back at some of the previous posts.

Now on to our current weather. As the title of this blog states, not a whole lot to worry about with the next little system. I’m going to show you three different computer models and how they come up with a pretty consistent amount of precipitation for these little system that arrives on Monday night and continues until midday on Tuesday. The first model is the 12z or 6AM run of the GFS:

On the GFS, there is only about .10″ of liquid for this system. Now the 18z or noon run of the NAM model:

Note the similarities between the two models. Finally, check out our NAM model from the noon run:

The RPM is a higher resolution model and gives a general 1″-2″ snow forecast for the area. It is not too often that all of these models agree, but I feel pretty confident with a 1″-2″ forecast for our area. This will be a fluffy snow that you may be able to brush off with a broom instead of shovelling. Have a great day.

Mark

Advertisements

Monday-Tuesday Snow Chance
January 30, 2010

***Watch WISN 12 News at 5, 6, & 10pm for the latest weather information!***

I hope you are enjoying your weekend!  Thank you for spending a few minutes with us on the Weather Watch 12 blog. Today we will go over our next good snow chance for late Monday and into Tuesday.

Before we discuss the snow chance I encourage everyone to look a few blog entries below this one to read our February forecast that was issued this past Tuesday, January 26.  If you are curious, I use a weather pattern theory known as the LRC to help make the long range weather forecasts.  The last long range forecast I made for Southeast Wisconsin was back on December 29.  This is how I was forecasting the last week of January.  The storm I was forecasting was the one that occurred and brought the area rain last weekend, and of course our temperatures have been in the deep freeze for a few days.

This storm should be followed by a push of arctic air that likely will end the month cold.

So January is ending cold as expected, and February will greet us with a chance of snow.

Let’s look more at the timing and possible snow chances for late Monday-Tuesday.  A clipper system will push into the Midwest Monday Night and Tuesday.  This will help to create an area of light snow.  The light snow should reach Southeast Wisconsin either late Monday afternoon, or Monday evening.  Once the snow begins it should snow for at least 12-18 hours.  The snow will be light, but averaging out the forecast snow totals, puts our area in a general 1-3″ snow band.

Below is the 18Z NAM total precipitation forecast from Monday thru Tuesday.  This would put Milwaukee in the 1-3″ snow band, with a heavier 3-5″ snow over parts of Iowa.  If Milwaukee does pick up 1″ or more of snow, it would be the first 1″ snow since January 7!  Pretty remarkable since this recent ‘dry’ period is generally our snowiest each year!

The forecast will likely shift around some, so make sure to catch the most updated forecast on WISN 12 News.  We have the most weekend news of any station in Milwaukee, so you can trust that we will keep you updated now and in the future!

If you haven’t already, make sure to join us on Facebook: WeatherWatch 12   Also, you can follow our updates on Twitter.  And best of all, you can always post your thoughts and questions in the comments section of this blog.  Mark and I would love to chat about the weather!

Jeremy Nelson

Moon Over Milwaukee…Snow Chance
January 29, 2010

Watch WISN 12 News this weekend from 5-6am, 7-9am, and at 5, 6, & 10pm!

Thank you for stopping by the Weather Watch 12 blog!  The arctic air that has been gripping the area for the past few days will begin to ease this weekend.  We will discuss milder days ahead in the blog, but let’s start with a beautiful sight that everyone should be able to enjoy tonight. 

The full moon will be the biggest and brightest this entire year tonight!  It will be 14% bigger and 30% brighter due to the timing and proximity of the Moon’s orbit, in relation to that of Earth.  I encourage everyone to bundle up and step outside for a few minutes to enjoy this great sight.  If you take a picture, feel free to email it to me at  jdnelson@hearst.com and I will include a picture in our blog on Saturday.  You can always upload you weather photos to our U-Local section on WISN.com

Before we discuss the weather for the weekend, I want to share a high resolution picture from the NWS.  This photo highlights a couple of features.  First, the ice that has accumulated on Lake Michigan near Milwaukee extending to Kenosha.  Also, the very thin white line in northern Wisconsin.  This is where a torndo knocked down and uprooted trees leaving a clear path.  That path is now covered with snow, and is detected by the visible satellite.  This picture was taken on Thursday, January 28.

Heading into the weekend temperatures will moderate slightly, with highs back into the 20s.  Both Saturday and Sunday look quiet, with a little more in the way of sun on Saturday.  Our next chance of light snow heads in our direction on Monday.  This is a clipper system that I discussed when I made the long range February forecast earlier this week.  This clipper could bring some light snow accumulation to southern Wisconsin.

Below is the total precipitation forecast from the 18Z GFS.  Keep in mind this is just one computer model we use.  But this would put about 1-3″ in the darker shaded area.  Other models have that shaded area right over ALL of Southeast Wisconsin.

In Milwaukee we are really overdue for snow.  It has been 23 days since our last 1″ snowfall!  Hang in there snow lovers…I think February will present a few chances for snow.

That’s it fo now…if you ever have a weather question please leave it in the comments section of the blog!  Have a great weekend!

Jeremy Nelson

Thank you, cold.
January 28, 2010

It’s not often that we can get excited with cold temperatures, but if you do not like snow you should be thanking the cold air. The cold air is keeping a major winter storm well to our south. Parts of north Texas, Oklahoma, Kansas, Missouri, Illinois, Arkansas, Tennessee, and Kentucky are going to get slammed with ice and snow. Some areas will get as much as 3/4″ of freezing rain while others could see a foot of snow. These same areas were in the sixties yesterday.

The above image is from the NAM model showing the cold air in place in our area. Cold air is very difficult to displace so instead of this “panhandle” storm hooking toward us, it will stay well south.

There is a good chance that tonight will be our coldest of the season. If we still had snow cover in Milwaukee, I think our temps would go below zero. We will be very close to zero near Lake Michigan, but some inland temps could go as low as -10. Take a look at the lows from this morning:

Most areas were near zero and the low in Milwaukee was 6 degrees. Currently, at 7:00 PM on Thursday night it is 8 degrees in Milwaukee and 3 in Waukesha. The winds are lighter tonight and it is clear so we have good radiational cooling conditions. The good thing is with the light winds we will not have wind chills as low as they were on Thursday morning. The coldest air lasts into Saturday before our temps will finally get back into the twenties. Have a great night and stay warm.

Mark

Arctic Blast
January 27, 2010

***Watch WISN 12 News for your most accurate forecast at 5, 6, & 10pm***

Thank you for spending a few minutes with us on the Weather Watch 12 blog!  Stepping out the door this morning was a drastic change as all locations in Southeast Wisconsin dropped into the single digits.  Now the question is how long will the bone-chilling cold stick around?

There is good news and bad news to the cold.  The good news is that the worst of the cold will only last about 2 to maybe 3 days.  The bad news is that we could see the coldest temperature of the entire winter season in Milwaukee by Friday or Saturday morning.  Inland locations will likely dip below zero on these nights.

Now high temperatures during this time will be running a good 10-15 degrees below average.  By Thursday afternoon, some areas may only see highs around 10 degrees!  The map below is a forecast tempeature map for Noon on Thursday.  The dark blue shade across Southeast Wisconsin represents temperatures of 5-10 degrees!  Keep in mind our average high is now around 30 degrees!

The cold air will hang around into the weekend, but beginning Sunday, temperatures will slowly moderate.  By the 1st of February we should see highs back to around average as a clipper system moves in our direction.  This will likely also produce some snow showers.

Here in the United States, specifically Mount Washington in New Hampshire, has held the world record for fastest wind gust ever recorded on Earth since 1934!  But it was determined recently, that another place in the world topped this long standing record.  Below is a picture of Mt. Washington, and below the picture the summary of the old and new wind records.

Mount Washington has lost its distinction as the site of the fastest wind gust ever recorded on Earth, officials at the Mount Washington Observatory said. The concession came after the World Meteorological Organization said on its Web site that a panel of experts reviewing extreme weather and climate data turned up a 253 m.p.h. gust on Barrow Island, Australia, in 1996 during Cyclone Olivia. That tops the 231 m.p.h. recorded atop Mount Washington on April 12, 1934.

I think it is safe to say this these type of gusts would make for a bad hair day!  I can’t even imagine what this type of wind must be like, the strongest wind I ever experienced was around 90mph back in June of 2008 near Salina, KS.

If you are ever looking for more information, please join us on Facebook at WeatherWatch 12

Make sure to watch our newscasts for the most up-to-date forecast information.  And remember you can view the February forecast right below this blog entry!

Jeremy Nelson

February Forecast
January 26, 2010

***Watch WISN 12 News at 5, 6, & 10pm for the latest forecast!***

Thank you for stopping by the Weather Watch 12 blog. In today’s blog we will take a look back to the January forecast that was made on December 29, and then we will go over what to expect for the entire month of February in Milwaukee. Will winter storms hit the area, how cold will it be, and is Spring near? All of those questions will be answered in the complete February forecast!

Making long range forecasts is always tricky, but a weather pattern theory known as the LRC allows for accurate long range weather forecasts to be made. LRC stands for Lezak’s Recurring Cycle.

I have been very excited to introduce this theory to viewers here in Southeast Wisconsin. I first learned about the theory 4 years ago while working in Kansas City. Here is what the theory states:

  • A unique weather pattern sets up every year between October 1st and November 10th
  • The weather pattern cycles, repeats, and continues through winter, spring and into summer. Identifying the cycle length helps tremendously when making long range weather predictions.
  • Long term long-wave troughs and ridges become established and also repeat at regular times within the cycle. These dominant repeating features are a clue to where storm systems will reach peak strength, and where they will be their weakest.
  • The LRC is a winter-long pattern! There is a pattern! It isn’t just one long-wave trough, storm system, or ridge. It is a sequence of troughs and ridges that are cycling across the Northern Hemisphere.

To put this in very simple terms, the weather pattern that occurs in October and November repeats thru the Winter, Spring, and into the Summer. The cycle length will vary each year. Determining the cycle length each Fall really holds the key in using the LRC to forecast into the future. A very good idea of the cycle length is usually determined anywhere from late November thru December. Once the pattern goes thru its second cycle a period of days can be placed on the cycle length. As I have mentioned in previous blog entries, the cycle length this year is about 60-62 days.

Back on December 29 I used the LRC to make a forecast for the entire month of January. Over 3 weeks out, the storm that occurred this past weekend was forecasted, along with it also producing our warmest temperatures of the month. The arctic air that is heading our way for Thursday/Friday was also highlighted in this forecast! Below is the forecast for the last 2 weeks of January from that December 29 blog entry.

January 16-23

This week of January picks up with the storm described above. Back in November the storm impacted the area from the 15th to the 19th. We could see snow showers early in the week with cold temperatures, and then a warm-up around the 20-23. The warm-up around the 20-23 into the early part of the following week could bring us our warmest high temperatures of the month, possibly a January thaw. By the end of this week the focus will shift to a potential storm.

January 24-31

The last week of January looks to be the most exciting and wettest of the month for our area. Let’s start by looking back to November and our wettest storm of that month. This is a 500mb map from November 24.

If we are going to see a major winter storm during January, I think this would be the storm and timeframe for our area. Again, the question will be where does it move, but unlike the storm around the middle of the month, this one should lift north into our region. This storm could be rain, sleet, snow, or all of the above. This storm should be followed by a push of arctic air that likely will end the month cold.

 

The book is now closed on January, what can we expect for the month of February? This foreast will be broken down into 4 periods with map comparisons to highlight the focal points of the month. After a somewhat quiet month of January with really only 2 storms systems, February should be much more active for Southeast Wisconsin, and also a little colder.

February 1-7

The weather pattern during the month of February should be a lot like the one that occurred this past December. Back on December 3, an Alberta Clipper raced across the northern U.S., and in its wake pushed colder air into the region. This is exactly how the 500mb(roughly the middle of the atmosphere) chart looked that day. A large trough was located over the Midwest, with a ridge pushing up the West Coast.

Comparing that map to what’s ahead for the first couple days of February shows the weather pattern continues to cycle! The map below is a forecast map from the 6Z GFS. It shows the trough over the Midwest and also a ridge pushing up the West Coast.

So for the first week of February, we can expect a clipper system right around Groundhog Day. This should provide the area with some light snow, snow showers, or flurries. The Groundhog, at least in Southeast Wisconsin should not see his shadow. This should not be a major storm, but could produce a very light accumulation of snow. Behind that clipper there will be a shot of cold air, but it should not last too long. Temperatures the first week will be average to slightly below average as a whole.

Late in this period a trough should be near the West Coast, and one that will likely impact our weather!

February 8-14

In discussing this period, let’s start with a remember when? Looking back into December, a major winter storm hit southern Wisconsin around Dec. 8-9. Madison, WI had around 18″ of snow, and here in Milwaukee about 3″ and also a good deal of rain.

This is how the storm looked at 500mb on the morning of December 9. An upper low was over northern Illinois, and colder air was beginning to wrap into the storm.

The February version of this storm should return! This does not mean 18″ of snow will fall or it will be more rain than snow in Milwaukee, but what I’m focused on is that the overall pattern will repeat, producing a storm. It would be hard for this storm to be as intense as the December storm, considering the pressure with that storm was the equivalent of a category 2 hurricane! Back in December the jet stream phased, meaning the northern and southern brances of the jet stream essentially became one, allowing for the abundance of moisture and an intense storm.

Looking back to October 8-9 when the cycle was just forming, this part of the pattern did produce a storm, but only 0.21″ of precipitation occurred, comparing that to early December’s 0.84″, the result of each storm at the surface varied. 

For this forecast I do think a storm will form over the Midwest in the Feb. 7-9 timeframe and likely bring snow to many areas. If enough warm air is pulled in, a mix or rain could occur. This will be one of potentially two major storms we see during February, and could be the biggest snow maker of the month for parts of our area.  This potentially large storm could impact the region through the 10-11 as a quick shot of arctic air is drawn in on the backside of the storm.  Again, it would be very tough for this storm to be as strong as the previous time through the cycle, but it will likely be somewhere between the October and December versions.

By late in this period another clipper system will move through the region producing snow showers. Ahead of this clipper temperatures will likely jump to around average…in the 30s. Behind the clipper another push of cold air will drop temperatures.

February 15-21

This period of February will likely bring active weather to parts of the South, East, and Northeast. We’ll watch for a big storm to form and move from the Gulf Coast to the East in the 17-19 timeframe.

Tempeatures should moderate during this period, and by the end, our focus will shift to a storm in the West. There could be light snow by the 21st around Wisconsin.

February 22-28

The last week of February should bring a couple of things to Milwaukee…the wettest storm of the month…and also the warmest high temperature of the month. Let’s compare this back to December first.

The map below is from December 24, two well defined upper lows were stretched across the Plains. This would eventually form into a very impressive storm that brought over 1.50″ of precipitation to Milwaukee…most of that falling as rain. Looking back 60-62 days from December 24 to October…keeping in mind the 60-62 day cycle…another very wet storm produced over 2.20″ of rain in Milwaukee.

This was a long duration storm for our area that came at us in a few pieces, with the main energy around December 24-25. I do expect this to be a wet storm once again, with the greatest impact from February 23-25, but even around the 21-22 some snow or a mix could occur. This storm should once again bring rain to the region, with some mix/snow. This would be the second of 2 big storms for Milwaukee in the month. During this period we will also see our warmest temperatures of the month…likely occurring around 23-25.

Behind this storm the month should end cool.

Overall for the month: I expect temperatures to be near average, and precipitation to be above average. Snowfall should also be close to average…11.3″

Those are my thoughts and the reasoning behind this February forecast. Again, this is a theory that I believe in. Mark, Sally, and Lyra are still watching and learning about the LRC. I encourage anyone that has never seen or heard about the LRC to follow along in the blog and ask questions over the next 6-12 months. I am still amazed each time I see the pattern cycle!

Feel free to leave your thoughts and questions in the comments section of the blog. I will do my best to answer any questions that you may have.

Have a great day!

Jeremy Nelson

January Thaw Ends
January 25, 2010

Fifteen days in a row. That is how long our temperatures have been above average. This, along with the weekend rain, has melted off much of our snow. The fifteen day January thaw was a long one, but we still have a lot of winter to go. It’s always a fine line to please folks in Wisconsin. Many of you like warmer weather in the winter, but there is a large number that also love the winter-time activities that need snow to survive. If you like it colder this forecast will make you happy. The cold looks like it is going to stick around for awhile.

The cold is coming in two waves. The first wave arrives tonight.

The above image is the 850 millibar chart for Tuesday at noon from the NAM model. This is from UW-Madison’s web site. The 850 millibar temps often correlate to what we can expect at the surface. The colder the 850 temps, the colder the surface. On Tuesday afternoon, the 850 temps will be around -10 degrees Celsius for Southeast Wisconsin. This will correlate to a surface temperature, because we will get some sunshine, about 24 degrees.

The second image shows the second wave of cold air. The above image is for midnight on Thursday night. The 850 millibar temperatures will be around -22 degrees Celsius. This will correlate to night-time lows below zero where there is any snow cover left, and low single digit temperatures where there is no snow cover.

No big storms on the immediate horizon. Stay tuned to weather watch 12 for the latest. Thanks for reading the blog.

Mark

Rain Totals…Week Ahead
January 24, 2010

***Watch WISN 12 News for the most accurate forecast!***

Thank you for stopping by the Weather Watch 12 blog!  The weekend was very mild across the area and also wet.  Highs topped out in the low 40s on Sunday, our warmest of the month.  Rain totals ranged from about 0.25″ to 0.50″ across our viewing area.

Here are some of the totals we received.  Remember, if you ever have a rain or snow total to post it to the comments section of our blog.  We love to share your totals in the blog and also on WISN 12 News.

  • Madison 0.52″
  • Sheboygan 0.46″
  • Greenfield 0.35″
  • Racine 0.29″
  • Milwaukee 0.26″

Those are actual toals out of a rain guage.  Now let’s look at the radar estimated totals from the NWS.  This shows generally 0.25″ to maybe some isolated pockets of 0.75″ in Ozaukee County. 

This storm will continue to impact the region on Monday with snow showers and flurries.  Right now it does not look like any snow accumulation for our area.  Highs should be in the 30s on Monday, and then Tuesday is a transitional day.  The transition being from a ‘milder’ air mass to a colder one, and it will also be a dry day.  Another storm will impact Southeast Wisconsin on Wednesday, this should bring some light snow to Milwaukee. 

The main energy with this storm should stay to the south, but enough will sneak in our area to give us a chance of seeing light snow.  Right now the accumulation looks to be on the light side.  Any snow that falls will be light and fluffy with cold temperatures in the 20s.

After this brief period of light snow sweeps through, we can expect the coldest tempeatures in a long time to invade southern Wisconsin.  By Thursday and Friday many areas will not even reach 20 degrees for a high!  This would be the coldest airmass since the first week of January when lows were in the single digits, and highs were in the teens to low 20s.  The cold airmass will put and end to nearly two weeks of above average high temperatures for Milwaukee! 

Thank you for stopping by the Weather Watch 12 blog!  Remember you can also join us on Facebook at WeatherWatch 12  Your thoughts and questions are always welcome in the comments section of this blog. 

Jeremy Nelson

Rainy Weekend…Colder Days Ahead
January 23, 2010

***Watch WISN 12 News at 5, 6, & 10pm for the latest radar updates!***

The weekend storm is here!  It has been a dreary, foggy, and drizzly Saturday across Southeast Wisconsin.  The steadier rains will arrive tonight and continue into the first half of Sunday.  This still looks like a wet storm, with top end rain totals around 0.75″ somewhere in our viewing area.  Let’s discuss the next 24 hours in-depth.

Heading into Saturday evening/night a large area of rain over Iowa and Illinois will push into Wisconsin.  This area looks pretty impressive on radar as of 2:34 p.m. Saturday.  The yellow and orange colors represent moderate to at times heavy rain.  This is still hours away.  On the map below I labeled Milwaukee for some prespective. 

Saturday Night into the first half of Sunday will provide the area with the bulk of our rain total.  Those totals around Milwaukee should be in the 0.50″ to 0.75″ range.  There may be a few isolated areas that see slightly higher totals.  Our high resolution computer model is shown below.  You can always click on the maps for a larger view.

By Sunday afternoon and evening colder air will gradually work into the region.  This should allow for a slow changeover to flurries or snow showers.  At this point any snow accumulation should be minor.  With snow showers on Monday, there is a chance of a dusting or maybe half inch of snow, but probably nothing more than this.

Starting on Tuesday, highs will fall back into the 20s as a chunk of arctic air pass our area a visit.  The map below is a temperature forecast map from the 12Z NAM for this coming Tuesday morning.  Notice the really cold air is waiting in the wings over the northern Plains.  Some of this colder air arrives in Southeast Wisconsin for Wednesday and Thursday.

If you happened to put out your rain guage for this weekend’s storm, please drop your rain totals off in the comments section of the blog.  Also, if you have a weather question you can always post it there too!  For more weather updates make sure to join our Facebook page at WeatherWatch 12   Tune into WISN 12 News all weekend long for updated forecasts and also live radar!

Have a great weekend!

Jeremy Nelson

Weekend Storm…How Much Rain & Snow To Expect
January 22, 2010

***Watch WISN 12 News at 5, 6, & 10pm for the latest on the rain and snow this weekend!***

Thank you for stopping by the Weather Watch 12 blog!  If you are new to the blog welcome, and if you stop by each day welcome back!  Right now we are going to continue our discussion on the weekend storm for Southeast Wisconsin and what you can expect.

The storm that is headed our way brought inches of rain to the West and feet of snow in the mountains.  One record broken during this storm that really stood out to me occurred in Los Angeles on Thursday.  I mentioned this on our newscasts, but if you missed it here was the record that was broken.

AT 121 PM PST THURSDAY JANUARY 22ND…THE BAROMETRIC PRESSURE AT LOS
ANGELES INTERNATIONAL AIRPORT FELL TO 29.07 INCHES OF MERCURY…OR
980.0 MB. THIS BREAKS THE PREVIOUS RECORD LOWEST BAROMETRIC PRESSURE
READING OF 29.25 INCHES…OR 990.6 MB…SET ON JANUARY 17TH 1988.

PRESSURE DATA RECORDS AT LOS ANGELES AIRPORT DATE BACK TO 1931.

This shows just how strong this storm is that will head into the Midwest this weekend.  The big question for Southeast Wisconsin is, when does the rain begin, how much to expect, and when will it change to snow.  Those are the questions I will try to answer in this blog.  Just remember that new data is always flowing in to our forecast center, and for the very latest information tune in to our newscasts at 5, 6, & 10pm!  Also, on Saturday we will be tracking the rain on radar from 5-6am, 7-9am, and at 5, 6, & 10pm. 

Let’s start by looking at the how things will play out on Saturday.  We should wake up to dry conditions and cloudy skies.  Winds will increase to 15-25mph on Saturday, so expect a breezy day.  Temperatures will be in the 30s most of the day, but late it could touch 40 degrees.  Light rain or drizzle could move around midday, but be spotty.  That be possible in the afternoon too, before more light to moderate rain arrives late in the day and evening. 

Below is a forecast from the 12Z GFS for 6 p.m. on Saturday, notice the steadier rain to our west.  This should move in, and then we will watch the low pressure area over Oklahoma strengthen and head our way for Sunday. 

On Sunday there will be a period of steady rain before the colder air pushes into the region.  Any changeover to snow will likely hold off until mid-afternoon or later in some areas.  The snow does not look to be a huge part of the storm for Milwaukee.

To show what I mentioned above, one of our computer models still does not have all snow across Southeast Wisconsin by 6 p.m. on Sunday.  The green on the map is rain, and the blue is snow.  Even when the changeover to snow occurs, it looks like most of the precipitation would be done. 

By Sunday evening the total amount of precipitation will likely be around 0.50″ in Milwaukee give or take a couple of tenths on either side.  The map below is a forecast of the total precipitation from this storm.  This model is our high resolution in-house model.

As Mark often likes to say, ‘more wet than white’, looks to be a good way to describe this storm.  If you have travel plans this weekend do not cancel them.  Any snow that falls looks to be late in the weekend and minor.  Once this storm passes we will focus on the arctic chill that may return for the middle of the week!

Thank you for stopping by the weather blog, and make sure to watch our newscasts for the updates.

Jeremy Nelson