For the last day or so, Chicago has had record-low humidity of all things, with dewpoints below 0°C for much of it:

This is the third day this year and only the 19th day in 142 years dating back to 1871 that the city has officially logged a relative humidity below 20%. At Midway Airport the relative humidity also dropped to 17 percent at 5pm.

This is the lowest relative humidity recorded in Chicago in more than six years since another 17 percent humidity was logged on February 20, 2006.

The other two low humidity days this year were back on April 8 and 9 when the relative humidity dropped to 19%.

Right now the dewpoint of 2°C on a temperature of 26°C gives us a relative humidity around 21%. For comparison, though, in Las Vegas the humidity is about 3%, so we're really not that dry here.

The Tribune has a graphic this morning pointing out a number of things about our lack of snow this past winter. It turns out, the snowfall on March 4th was the earliest last snowfall. That is, in the rest of recorded history (back to 1884), we've always gotten snow later than March 4th. Until this year.

Our entire season gave us only 11 days with 25 mm or more of snow on the ground (normal is 43); it was one of only 10 seasons (out of 128) with less than 500 mm of snowfall total (normal is 932 mm); and it's the second-shortest interval from first to last snowfall ever, at 117 days (normal is 174).

Of course, snow has fallen in 40 Mays of the 128 in history...so this could all be completely wrong. We've even gotten snow in June (on 2 June 1910). But it looks for now like we can add one more quantification to our wonderfully mild winter.

At least this year, in Illinois, where the average temperature is actually below March's—and it's still above normal:

The statewide average temperature for April 1-22 is 12.3°C. The statewide average temperature for March was 12.8°C, based on the latest numbers from NOAA. That means that April was almost a degree [Fahrenheit] cooler than March. What makes this even more freaky is that the April temperatures are still 1.9°C above normal!

BTW, the statewide normal monthly temperature is 4.8°C for March and 10.9°C for April, a ten degree [Fahrenheit] rise.

State Climatologist Jim Angel concludes by pointing out that we've only had one April in recorded history that was cooler than March, back in 1907. (Recorded history goes back to 1895.)

Chicago's record-shattering run of above-normal temperatures ended yesterday:

The abnormal, all-too-often record warmth, couldn't continue indefinitely. For 26 consecutive days, Chicagoans were treated to temperature levels which would have been at home in June and July. They were without precedent in March and early April.

The impact of that warmth continues, even in the midst of noticeably cooler air here. And while Easter weekend temperatures are expected to rebound to the 60s, an even cooler air mass seems determined to settle southward over the eastern half of the country next week.

April's opening 5-days continue to run 3°C warmer than the same period a year ago. The results of the abnormal warmth have been tangible. Vegetation in and around Chicago has bloomed 4 to 6 weeks early, a trend which has already spawned an extremely challenging pollen-season through which many continue to suffer.

Thursday marked the first day in 27 in which temperatures finished "below normal".

Next week it's supposed to be "seasonal," which could include a freeze.

The opening days of April have seemed a lot cooler than all but one or two days in March, but as it turns out, we're still above normal:

Despite the chilly feel to the air in recent days, the books closed on a 26th consecutive above normal average daytime temperature here Wednesday. The day finished 4.4°C above normal with a high of 14.4°C.

Any clarity in the forecast for the summer, though? The Climate Prediction Center still sees only a 33% chance of above-normal temperatures through the middle of June, as the La Niña that gave us the warmest March ever winds down to a neutral state over the next couple of weeks.

If we have the warmest spring followed by a cooler-than-normal summer, there will be much rejoicing at The Daily Parker.

Illinois State Climatologist Jim Angel rounded up some explanations of last month's record heat. Here's the NWS Chicago office:

The 2.7°C difference between the average temperature for March 2012 at Chicago-O'Hare and the previous record for warmest March is by far the largest difference between 1st and 2nd place between record warm or cold months in Chicago. The second largest difference between 1st and 2nd place is the 1.7°C separating the average temperature of January 1880 (4.3°C) and January 1933 (2.6°C) for the warmest Januarys on record in Chicago.

The 8.67°C departure from normal for March 2012 is the 3rd largest departure from the 1981-2010 normal for any month in Chicago. The only months that had higher departures from normal were January 1877, which with an average temperature of 4.3°C, was 8.9°C above the 1981-2010 average January temperature, and December 1877, which with an average temperature of 6.3°C, was 8.72°C above the 1981-2010 average December temperature.

For a more technical discussion, check out NOAA's analysis, which concludes:

A black swan most probably was observed in March 2012 (lest we forget 1910). Gifted thereby to a wonderful late winter of unprecedented balmy weather, we also now know that all swans are not white. The event reminds us that there is no reason to believe that the hottest, "meteorological maddest" March observed in a mere century of observations is the hottest possible. But this isn't to push all the blame upon randomness. Our current estimate of the impact of GHG forcing is that it likely contributed on the order of 5% to 10% of the magnitude of the heat wave during 12-23 March. And the probability of heatwaves is growing as GHG-induced warming continues to progress. But there is always the randomness.

April, so far, has been bog-standard normal.

Yesterday, the forecast for tomorrow's Chicago weather called for—no April Fool's joke here—32°C. Just a few hours ago the forecast had changed to a more comfortable 25°C, which is about as close to ideal as I can imagine. Just now, though, the National Weather Service says to expect nothing better than 13°C. Aw, come on.

On the other hand, Chicago had its warmest March in history, at 11.9°C, which beat the previous record (set in both 1945 and 1910) of 9.2°C. So, you know, the weather hasn't been that awful lately.

Illinois State Climatologist Jim Angel has crunched the numbers, and thinks (contra my own fears) that we might not get melted into little puddles of goo this summer after all:

Historically, a warm March has been followed by a colder-than-normal April on average (first map). That’s true not just in Illinois but across the U.S. On the other hand, precipitation for those same April periods was a mixed bag in Illinois (second map). Most of the state was near-normal while west-central Illinois was slightly wetter-than-normal.

I considered the entire May-August period in one set of maps. One popular question I get is “Does this warm weather now mean that we will get a hot summer?” At least historically, the growing season following a warm March does not show a pattern of above-normal temperatures. On average, they have been remarkably mild in temperature.

I still worry that the really warm lake temperatures and the lack of snow cover during the winter, followed by an unprecedented 8 days of 27°C weather this month (not to mention the hottest March in recorded history), can't help but yield a brutal summer.

Angel has the data, though. I tend to trust data. I should be reassured...but I'm also from Chicago.

And now Chicago is back on track for a record March. We woke up this morning to the gray 5°C weather we had all day yesterday, but right now O'Hare is up to 23°C—a normal temperature for Memorial Day.

Warmest March ever. Warmest January to March ever. Let's see if we get the warmest spring ever...

Via reader DB, a report of a coyote captured in downtown Boston:

At about 3 p.m., the 40-pound animal was finally located by Animal Rescue League workers. It was found cowering next to a downtown building near the corner of Lincoln and Summer streets, surrounded by a crowd of curious onlookers and police. Using teamwork, a large net, and a catchpole, the rescue workers were able to catch it.

[A Boston Animal Rescue League spokesman] suspected that the animal most likely was able to enter the city by following train tracks, but couldn’t find its way back. He said this happens a few times a year and that coyotes are much easier to catch than deer.

We've had coyotes in Chicago news a few times in the past couple of years. I've seen them as well, the last time right by the Whole Foods in Lincoln Park. I love how they've learned to adapt to us—and what they're doing to the rabbit and Canada goose populations. (Sorry, Bugs, you're just a long-eared rat.)

The hits just keep on coming as Chicago hits yet another new heat record (28°C):

In Chicago...prior to this year there had only been 10 days in March with highs in the 80s [Fahrenheit, 26.7°C], which means on average, Chicago only sees an 80 degree high in March once about every 14 years. Already this month, there have been seven [now eight—db] days at or above 80. Including the [eight] days at or above 80 this March, there have now been a total of [18] March days at or above 80 in Chicago. This means about one third of one percent of all March days have been in the 80s in Chicago.

The last time Chicago saw an 80 degree temperature during the month of March (prior to this year) was over 22 years ago back on March 12, 1990, when the high temperature was 81.

Here's the updated table:

No, no global warming here, you can go about your business...

First, just a nod to the eighth record temperature in a row that Chicago just set. Tom Skilling's blog entry this morning maps out the carnage, including record pollen levels, the hottest lake temperature readings ever for this time of year, and a forecast for above-average temperatures going into April. Let me tell you how thrilled I am that we've skipped spring and gone straight to July. As my servers start to melt and I lose sleep because the house is too hot, I find myself wishing for autumn the day after the March equinox.

It's not that warm in Paris. Here's another view of the Pont Neuf, which I like a little better than the one I posted Sunday:

And thank you, Eurostar, for making this all possible:

I don't want to lose these things:

• The Economist hosted an online debate about aviation security between security expert Bruce Schneier and TSA director Kip Hawley.
• The Atlantic explains why conservatives are afraid of cities.
• a la card Chicago, which sells a deck of 52 $10-off coupons to area restaurants, has a one-day promotion today for 50% off. (Enter code "SPRING2012" in the appropriate box.

That is all. More UK and France photos later today.

Happy Spring. The equinox happened less than 11 hours ago, which usually means Chicago has another six weeks of cold and damp weather. Not this time. Trees have buds and flowers, insects have started buzzing around, and as of about an hour ago, we've broken (or tied) our seventh consecutive heat record. This, by the way, is also a record (greatest number of temperature records broken consecutively), breaking the record set...yesterday.

Here are the temperature records we've set so far this month:

Today's forecast high would make it feel more like mid-June than mid-March.

Meanwhile, it's snowing in Arizona...

Update: O'Hare temperature is 28.9°C at 13:51.

I'll have more weekend photos later today (but probably not another post on our record heat wave. Before that, I just found out some great news about Chicago's next major park:

[Chicago mayor Rahm] Emanuel said [at a press conference last week that] initial funding had come together for the $100 million project, which is expected to begin construction later this year and be completed by 2014. Designed by Arup, Ross Barney Architects and Michael Van Valkenburgh Associates, the new park will have benches and foliage on either side of a two-way path.

It looks in renderings much like New York City's High Line, but will be nearly twice as long and with gentle curves and dips. It will also allow bike traffic and include several green space access points at ground level.

Besides offering expansive views across several Chicago neighborhoods, the new park will improve local transport links. The multi-use trail will connect the west side to areas near the lake and the Loop, and the anchor parks will link the trail to L train stations and major bus stops.

The Chicago & Pacific Railroad originally built this 4300 m stretch of rail line at ground level in 1872. After a series of accidents involving pedestrians, the tracks were elevated about a century ago, but have been out of use since the mid-1990s. Within a couple years, the determined and the curious will no longer be forced to slip through fences to use the space and enjoy the view.

I've been looking forward to the project getting off the ground moving forward for years. I haven't taken Parker up there yet, because it's (a) trespassing and (b) covered in broken glass, but possibly in the next week or two I'll go up there with my camera.

For more background, the Chicago Reader had a long article about the trail a couple years ago.

Apparently I've missed some unprecedented weather back home this weekend:

Saturday's high temperature at Chicago's official O'Hare International Airport observing site hit 28°C—the unprecedented fourth consecutive day in the 80s [Fahrenheit]. Sunday's anticipated 29°C high will make it a record 5 straight 80-degree days. Weather records dating back to 1871 should continue to fall as Chicagoans experience a stretch of warm temperatures never before observed in March. Sunday will mark the 6th straight day of 70-degrees or higher, eclipsing the previous record 5-day run on March 12-16, 1995.

The other shoe will drop mid-May or early in June. After the previous 5-day record in 1995, we experienced the hottest summer on record. The lake never froze over this year, and right now it's 6°C warmer than usual, so it won't hold off the summer heat effectively.

I'm afraid. I'm very afraid.

As of 13:51 CDT, the official temperature at O'Hare hit 26°C, passing the previous March 14th record by a degree. Will it get warmer?

The high temperatures at O'Hare the last three days have been 21°C, 18°C, and 21°C, all of them very close to the normal temperatures for mid-May. Right now it's 21°C, and forecasters expect record temperatures today and tomorrow (with a brief interlude tomorrow afternoon as temperatures plummet 11°C for a few hours).

The record high for March 14th is 25°C, set in 1995, during Chicago's longest string of 21°C-plus temperatures in history (5 days, from March 12 to 16). With a forecast (record!) high of 27°C tomorrow (beating the record of 23°C, also set in 1995), it's more like June than March.

Not to beat the drum or anything, but warm springs usually lead to really hot summers. Expect whinging from The Daily Parker in about two months.

Two days each week I have to go out to a client's office about 40 km from home. Only one route works to get me there, and that route includes the infamous Eisenhower Expressway (I-290) leading to the west from the Chicago Loop.

In the last few years, though, the Illinois Dept. of Transportation and neighboring agencies have created Travel Midwest, which has vast stores of traffic data. This has helped me stay sane. The site allows you to query the database to find out, in simple visual charts, when traffic is worst.

This chart compares my morning commute from the Circle Interchange to Wolf Road (22½ km). The red line shows travel times Monday through Thursday; blue line shows Friday times. (The data are from the last 12 months.) This shows why I hit the road around 8:30, instead of earlier, which gets me to the Eisenhower around 9 and here by 9:30:

But here's the return trip; again, Monday-Thursday is red and Friday is blue:

Then there's the chart going the opposite direction right now:

In the chart above, the thick red line shows the mean travel time, and yellow area shows 1 standard deviation on either side of the mean. The lines at 15, 23, and 56 minutes represent 88 km/h (full legal speed), 56 km/h, and 24 km/h. At the moment, the 65-minute travel time means traffic is moving at the breakneck speed of 20.6 km/h, which most bicyclists would find a relaxing speed.

I think I'll stay put for a while. Damn.

Having this information makes it relatively easy not to travel when everyone else is on the road. Yeah, I get home a little later, but the cost to me of spending 30 minutes in slow traffic is higher than the cost of shifting my commutes an hour forward.

We have our first really great spring day—it's 18°C and sunny—and I'm inside. It's also the warmest day we've had since November 13th (21°C).

That is all. Back to the mines.

The City of Chicago received its first city charter 175 years ago today:

Chicago's earliest charters reflected its small population, restricted geographic area, and limited governing needs. These first town charters were conferred in 1833 and 1835, when only a few hundred settlers clustered on a small site along Lake Michigan. Under its town charters, Chicago was governed by an elected Board of Trustees which wielded little political or financial power. In 1837 Chicago received its first city charter, which divided the city into six wards, allowed for a mayor elected to a one-year term, and legally incorporated Chicago as a municipality. The city grew so rapidly thereafter that new charter legislation was constantly needed. In 1847 charter legislation increased the wards to nine and designated annual elections for a city attorney, treasurer, tax collector, and surveyor. Still another charter was granted in 1851, followed by more charter legislation in 1853, 1857, and 1861.

On 4 March 1837, Chicago had 4,170 people spilling out of 250 Ha; today, with 2.6 millions in 567 km², we're the 3rd largest city in the U.S. and the 53rd largest in the world. (The metropolitan area, with 9½ million people, is 29th largest in the world.)

On the day Chicago became a city, the spot where I'm sitting was a few meters above a marshy beach, 4 km outside of town. Today it's considered "downtown" in one of the most vibrant and well-balanced cities in the world. And it's my home.

While Chicago finished its ninth-warmest (meteorological) winter in history on February 29th, Illinois as a whole finished its third warmest:

This year the average winter temperature was 1.2°C, 2.9°C above normal, and the third warmest winter on record. Here are the top four warmest winters. As you can see, we had a two-way tie for second place.

• First place, the winter of 1931-32 at 2.8°C;
• Second place, a tie between 1997-98 and 2001-02 at 1.4°C;
• Third place, this winter at 1.2°C.

Not only was it warm in terms of the average temperatures, but this winter lacked the really cold weather. Only a few place had temperatures drop below zero [Fahrenheit, -17.2°C]. The coldest reading for the winter was a mere -21°C at both Galena and Elizabeth in the far northwestern corner of the state.

Chicago had no days below zero Fahrenheit, thanks to the inland sea next to us.

We're now looking forward to a warm and wet spring...

That's where Chicago found itself today, inside the warm, dry southern sector of a major winter storm. The temperature got up to 15°C, with 65 km/h wind gusts, but as the cold front has pushed through behind the dry wedge, temperatures have fallen 6°C in the last three hours.

Still, today we finish the 10th warmest winter in recorded history:

Meteorological winter finishes as it began in Chicago---milder than normal. The three month season is noteworthy on a number of fronts. It's the mildest winter in 14 years and has posted more 40-degree (Fahrenheit) and warmer temperatures than any winter in the 80 years since 1931-32. It also ranks 10th mildest of the past 142 winter seasons.

Each of the three months of soon-to-close meteorological winter 2011-12 have posted temperature surpluses. February becomes the fifth consecutive month in Chicago to finish with temperatures which have averaged above normal. And as if that's not impressive enough, a stunning 76 of this winter season's 91 days—84 per cent of them—have finished at or above normal!

Climatologists predict that spring will be warm and wet as well. I can definitely get used to winters like this, though.

We came close. Mid-January it looked like Chicago would have its warmest winter in 80 years, but with the cool-down last weekend, the ranking has slipped a bit:

Two days remain in February and the 2011-12 meteorological winter season! It closes at midnight Thursday and is on track to finish the 10th-warmest December through February period of the past 142 years.

Estimates that this season's average Chicago temperature is to come in at 0.3°C places it 3°C above the long-term average and the mildest here since 1997-98's 0.5°C average.

But:

The chances for a -18°C or lower temperature occurring this late in the cold season are fading fast. Prospects "low" at best. Failure to produce a 0-degree reading would make this only the 13th cold season since the city's observational record began in 1870 to be "zero-free" and mark the first time in the three decades since 1982-83 that a winter has failed to produce a single -18°C temperature here.

While this winter's limited chill and lack of snow have garnered a good deal of attention, so has its generous number of 4.4°C and warmer days. The last winter winter with as many 40s (°F) occurred 80 years ago.

Even though we didn't get quite to the record, we're still quite happy that we went from fall to spring with only about four days of winter. I, personally, could get used to this.

At this time of year, people from the tropics to the poles really become aware of changes in the lengths of the days. Yesterday Chicago had 11 hours of daylight for the first time since October 18th; we get 12 hours of daylight less than three weeks from now. Tuesday the sun set at 5:30pm for the first time since standard time returned on November 5th; it sets at 7pm on March 16th.

From the solstice through February 1st we only get about one additional hour of daylight (though, because of the Earth's orbit, most of it comes in the evening). But the really dramatic changes are now: from February 20th to April 20th, we get 3 more hours of daylight—an average of 3 minutes per day. Plus, the second weekend of March puts us into Daylight Saving Time, so sunsets occur more than two hours later in April than in February.

A direct result of lengthening days is increasing temperatures. It turns out that summer temperatures don't predict winter temperatures at all, but winter temperatures predict summer temperatures quite well. With only 12 days of snow on the ground this year, the warmest winter since the 1920s has felt more like Raleigh, N.C., than Chicago. This means, of course, next summer will feel like Raleigh as well. I can't wait.

Nature Nerd Naomi observed ice-free ponds up near Gurnee about three weeks earlier than normal:

Finally, there is no ice at all on the lakes today... late last week, some kids in my neighborhood fell through the ice... meaning that it wasn't thick, but there was an ice cover. Yesterday about half the water area was covered on most lakes, and today, nothing. This is an early ice-off, as you can see if you look at the dates below. (The kids were rescued, btw.)

2006 -- Mar 10
2007 -- Mar 18
2008 -- Mar 31
2009 -- Mar 9
2010 -- Mar 18
2011 -- Mar 18
2012 -- Feb 22!

With only a week left in meteorological winter, Chicago's weather continues its near-record mildness:

With 4°C+-degree highs predicted the next two days, the tally of 40s (°F) will grow to 46 by Thursday's close. That's nearly twice the 141 year average of4°C or milder temperatures through Feb. 23 and just shy of six times last winter's total of 8 days in the 40s over the same period.

In only 6 other winters----all but one of them occurring prior the beginning of the last century in 1900---have as many or more 40s been logged through Feb. 23. The most recent winter with a comparable number of 40s occurred in 2001-02 when 47 were on the books.

But: "An in-house analysis of a series of mild winters---not unlike this one---continues to indicate a bias toward warmer than normal summer weather, including more 90s (°F) than usual. In 7 of 10 years we examined, summer (June through August) temperatures and 32°C tallies each finished above normal."

Apparently summer temperatures don't influence winter temperatures as much as the other way round. I like warm winters; warm summers, not so much. We'll see.

If you're driving in San Francisco, don't block the MUNI:

By early next year the city's entire fleet of 819 buses will be equipped with forward-facing cameras that take pictures of cars traveling or parked in the bus and transit-only lanes. A city employee then reviews the video to determine whether or not a violation has occurred — there are, of course, legitimate reasons a car might have to occupy a bus lane for a moment — and if so the fines range from $60 for moving vehicles to more than $100 for parked cars.

City officials consider the pilot program a success. "Schedule adherence" has improved, according to that update, as has general safety, since access to proper bus-stop curbs is impeded less often. In addition, the number of citations issued has risen over the past three years — from 1,311 in 2009 to 2,102 in 2010 and 3,052 last year, according to the San Francisco Chronicle.

At the root of the problem is a disconnect between the automobile and transit worldviews, transit planner Jarrett Walker explains in his excellent new book, Human Transit. (More on this in the coming days.) While an empty bus lane is actually a functional bus lane, an empty car lane is a wasted car lane, so drivers are quick to capitalize on what they view as a transportation inefficiency.

That's pretty cool. In principle, I approve of automated parking enforcement, such as Chicago's street sweeper cameras, even though I've had to pay fines as a result. Fair enforcement is all right with me. (But don't get me started on how Chicago puts up street-sweeping signs the day before...)

Illinois State Climatologist Jim Angel predicts our unusual warmth will continue through May:

One of the key things to come into play is the status of La Niña in the Pacific Ocean. A La Niña event occurs when ocean temperatures are colder-than-normal along the eastern part of the Pacific Ocean basin. The associated ocean and atmospheric pattern tends to give us a wet spring in states along the Ohio River Valley. [The National Climate Prediction Center] states that “La Niña is likely to transition to ENSO-neutral conditions during March-May 2012.” That’s government-talk for saying that the La Niña event is fading fast and will be gone before the end of spring.

The outlook for March in Illinois calls for an increased chance of above-normal temperatures and above-normal precipitation. The outlook for March-May calls for an increased chance of above-normal temperatures throughout the state. However, it shows an increased chance of above-normal precipitation in the eastern half of the state while the western half has “equal chances” of above-, below-, near-normal precipitation.

And, of course, they have art (click for full size):

The Illinois State Climatologist is wondering if 2011-12 qualifies:

The folks at the Chicago NWS office raised the following question. I would add to this that last winter Chicago O’Hare reported 1,470 mm of snow and 67 days with an inch or more of snow on the ground. This winter, through February 13, O’Hare reported 391 mm of snow and only 10 days with an inch or more of snow on the ground.

Plus, 78% of the days from December 1st until now have been above average, with more than half of those days almost 6°C above average. It's the 8th warmest winter in history, and the warmest since 1921.

There are still 15 days left in meteorological winter. We might actually move up in the ranks this year. We'll see.

I remember traveling in the 1970s and 1980s, when no one could reliably answer this question until the plane actually left the runway. But today I'm at O'Hare while snow is falling, and it looks like my flight will in fact take off on time despite the snow and the lengthening list of delayed flights on the arrivals board.

How do I know?

First stop is the American Airlines website. Their flight status tool says my plane departs on time from gate K5. And the page has a link to "arriving flight information," which tells me that the plane I'm on will land in 10 minutes.

Oh, really? Yes, really, as Flight Aware's real-time tracker shows me. At this moment, the airplane taking me to San Francisco is heading straight for the O'Hare VOR about 70 km away. (It's over Joliet—no, wait, now it's over Naperville!)

The airline has done it right. By providing real-time information, they're putting me at ease. Even if the incoming plane were circling over Springfield, that would still help me by letting me plan how long I can sit here working before I have to schlepp to the gate.

Update: In the time it took to write this entry, my plane has arrived, and I can see it taxiing towards me right now. I am not making this up. That's not my plane, by the way. That's a plane being de-iced, to show you why I might be a little on edge about my actual departure time today.

The Superbowl starts in a little over an hour, with weather in Indianapolis no one expected: clear skies and 9°C. In Chicago it's just a smidge cooler, but still a beautiful afternoon for February. Or for March, for that matter.

Parker gets one more walk before the game. Go Giants! (For why, see Robert Wright's decision tree on the subject.)

The thing I like most about February: at the end of it, Chicago has an hour and a quarter more daylight than at the beginning of it. Today we have 10 hours of daylight, the most since November 10th, and on the 29th we have 11 hours and 14 minutes.

I notice this every year around now, just as I forget every year how grim December can be.

With yesterday's temperatures more like April than January, Chicago magazine's explanation of it is timely:

So what is going on? It's the warmest La Niña on record. That brings the global temperature down, but causes different effects in different places. Chicago is going through a near-record warm spell—strong La Niñas correlate with above average temperatures, like the 18°C we hit in 1989 when the mean January max was 11°C, 2°C higher than this month's mean. Meanwhile, Alaska and northern Europe are suffering through deadly cold snaps.

This came to me through the WGN weather blog, which in the same story points out that groundhogs are less accurate than random chance at predicting the weather. Just a heads-up for tomorrow.

The normal temperatures in Chicago for January 31st are a low of -8.3°C and a high of 0°C.

Right now, the temperature is 13°C; the low last night was 7°C

The normal temperatures in Chicago for April 9th are a low of 2°C and a high of 13°C.

That is all.

I can scarcely believe I've had this guy for 10 years:

The car is named João, because he's from Brazil, and he seemed kind of like a Joe: He's a little rough around the edges, he's fun to hang out with, and he's super-reliable—except for the occasional hangover.

The photo is from the day after I got him. He's scarcely aged. (See, for example, this shot from last February. You can kind of see the dings, but he's still got a good profile.)

Via Sullivan, a snippet of conversation between Bob Dole and Newt Gingrich in the 1990s:

"Why do people take such an instant dislike to me?" asked a perplexed Gingrich, to whom Dole bluntly explained: "Because it saves them time."

In unrelated news, Parker and I are about to walk around in abnormally warm, sunny weather on what is statistically the coldest day of the year in Chicago. This is the warmest winter in 78 years, with the fewest sub-freezing maximum temperatures in 40 years. (Today was above freezing until a cold front edged through this morning; right now it's -1°C.)

Two items I haven't had time to read fully, and intend to do over the weekend:

• The Economist explores Boeing's immense order book;
• James Fallows has annotated the State of the Union address President Obama delivered Tuesday.

That is all.

Oh, except: tomorrow the sun sets in Chicago at 5pm for the first time since November 5th.

Chicago is experiencing the mildest winter in 78 years, which means anyone complaining about the weather lately needs serious mocking:

Though this season has produced some wintry moments, last Friday's snowstorm among them, the vast majority of days---82 percent of them---have posted above normal temperatures. What's more, we could find only 11 winters of the past 141 for which official weather records exist, which have been milder up to this point in time.

Chicago's average temperature since Dec. 1 is running 0.2°C, well above the 141-year average of -2.9°C and a stunning 6.3°C warmer than the same period a year ago. That's a difference which suggests many Chicago area residents have required 17 percent less home heating.

A multi-day burst of frigid arctic air heads into the area in waves late this week into the coming weekend. Any one of them, if fully developed, could produce several inches of snow. The first is due later Friday into Friday night---a second swings into the area just ahead of sharp cooling predicted Saturday into Saturday night.

The arctic chill will come and go fairly expeditiously, as has been the case with previous cold spells all season.

The mild disappointment Parker might feel about our weather this winter does not bother me at all. In Chicago, we say our weather builds character. After [redacted] Chicago winters in my lifetime, with a few in New York, Lisbon, and Raleigh for comparison, I'll take one year off from character-building happily.

I'm at O'Hare for the first time this year, wicked early for my flight. This happened because I left lots of time to dig my car out, get Parker sorted, get to the airport, etc. As it turns out, the howling wind cleared my car overnight; there was no traffic; the main roads are already clear because, really, it wasn't that much snow; and when I got to remote parking, an enormous pickup truck pulled out of a parking space, leaving a patch of cleared ground the size of Connecticut. So...I brought a Kindle, and my flight is on time. No stress, no worries, no checked baggage.

Working at home today (thus the earlier post with the dog). This is why:

The National Weather Service says it might melt on Sunday.

If Parker could have read this, he'd have been looking forward to this all day:

Yes, I know, I've posted remarkably similar videos before. Who cares? It's a dog having fun in the snow, which I think has universal appeal.

My team are all working from home today because we have the technology to do so, and we saw this:

A WINTER STORM WARNING REMAINS IN EFFECT FROM 9 AM THIS MORNING TO MIDNIGHT CST TONIGHT.

* TIMING...SNOW WILL DEVELOP DURING THE MID TO LATE MORNING HOURS AND CONTINUE THROUGH THIS AFTERNOON...ENDING TONIGHT. THE HEAVIEST SNOWFALL WILL OCCUR THIS AFTERNOON.

* ACCUMULATIONS...SNOWFALL TOTALS OF 5 TO 8 INCHES CAN BE EXPECTED.

* HAZARDS...SNOW WILL FALL HEAVILY AT TIMES RESULTING IN REDUCED VISIBILITIES AND SNOWFALL RATES OF AROUND ONE INCH PER HOUR AT TIMES.

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS COMMUTE THIS AFTERNOON. IN ADDITION...VERY COLD TEMPERATURES IN THE TEENS WILL MAKE SALT LESS EFFECTIVE AND COMBINE WITH HEAVY SNOWFALL RATES TO MAKE IT HARDER FOR ROAD CREWS TO KEEP ROADS CLEAR OF SNOW AND ICE. THE SNOW WILL ALSO RESULT IN SIGNIFICANT DISRUPTIONS TO AIR TRAVEL AS WELL.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER CONDITIONS ARE EXPECTED OR OCCURRING. SIGNIFICANT AMOUNTS OF SNOW ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. ONLY TRAVEL IN AN EMERGENCY. IF YOU MUST TRAVEL...KEEP AN EXTRA FLASHLIGHT... FOOD...AND WATER IN YOUR VEHICLE IN CASE OF AN EMERGENCY.

Parker is also working from home. If he could read, his attitude toward the weather warning might differ slightly from mine. On the other hand, we're both in the same room, which I think makes him happy anyway.

Updates and photos as events warrant.

We're having a very odd winter. After bottoming out at -15°C just yesterday, the temperature in Chicago has climbed past 6°C and it's getting warmer. Here's one consequence, which you can compare to Thursday:

Today's forecast calls for rain and 8°C; the record for January 16 is 14°C.

Rumors abound that American Airlines has two suitors, one we knew about and one we didn't. Since filing for bankruptcy in November, industry analysts have wondered with whom they would merge, twice-spurned USAirways the most obvious choice.

The new rumors, however, have Delta puttin' the moves on, which, if consummated, would make Delmerican (Amelta?) the world's largest airline and put the oneworld alliance in existential peril:

Since I'm generally bullish on the airline alliances (and competition between them), I'd tend to think the US Airways/oneworld route would be better for competition, and thus better for travellers. But the real question is what American government regulators and anti-trust authorities think about the whole idea. A Delta-American merger would produce a company that would control a huge chunk of domestic market—29.6%, double the share of its next biggest competitor, Southwest Airlines.

Another issue is whether Delta's supposed interest in acquiring American is serious or simply an effort to cause problems for US Airways and oneworld. It's hard to imagine that Delta's executives aren't aware of the regulatory problems a merger with American might face. Whatever happens, this struggle will be interesting to watch.

Blogger Matt Yglesias argues that an American/USAirways merger would be more patriotic, and "would give the United States three really big global carriers—United, Delta, and US/American—with the merged entity ideally joining the OneWorld alliance so we'd have strong representation in each of the three major global airline alliances." And it would keep Chicago one of aviation's world capitals, since a merger with Delta would encourage shutting either O'Hare or Delta's nearby hub in Detroit.

With this many rumors circulating, I expect we'll hear something definitive relatively soon.

...at least for a few days. From last night in Chicago:

And:

Here's the view at 11:30. Contrast with an hour earlier:

And here's 2pm:

4pm:

The first significant snowfall of Winter 2012 has started:

The National Weather Service says:

A WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 9 AM CST /10 AM EST/ THIS MORNING TO 9 AM CST /10 AM EST/ FRIDAY.

* TIMING...SNOW WILL BEGIN BETWEEN 9 AM AND NOON AND CONTINUE INTO FRIDAY MORNING.

* ACCUMULATIONS...SNOWFALL TOTALS OF 100 TO 200 MM ARE LIKELY WITH LOCALLY HEAVIER TOTALS POSSIBLE.

* HAZARDS...IN ADDITION TO THE FALLING SNOW...WINDS WILL INCREASE TO 25 TO 40 KM/H WITH GUSTS UP TO 55 KM/H BY AFTERNOON RESULTING IN BLOWING AND DRIFTING SNOW...ESPECIALLY IN OUTLYING AND OPEN AREAS. WIND CHILLS ARE ALSO FORECAST TO DROP TO -17°C TO -24°C BY FRIDAY MORNING.

* IMPACTS...ACCUMULATING SNOW AND REDUCED VISIBILITIES WILL LIKELY MAKE TRAVEL DIFFICULT FOR THE AFTERNOON COMMUTE TODAY...WITH TRAVEL CONDITIONS BECOMING TREACHEROUS AND EVEN DANGEROUS IN OPEN AREAS TONIGHT INTO EARLY FRIDAY MORNING.

As bad as that sounds, the NWS also predicts it'll be gone by Monday.

Hey, it's Chicago in January, and yesterday it hit 12°C. One or two days of snowfall is no big deal.

More photos as the snow accumulates...