January Thaw: Just how common is it? (Answer: Very)

[michsnowfreak]

With a January thaw on the way, how common is it to have one of these in the southern Great Lakes? Unfortunately, very common. Luckily this is by no means a prolonged torch, but it should be enough to rid quite an expansive area of snowpack.

 

I looked at the max January temp in Detroit every year since 1888. The results...

 

116 of the last 124 years Detroit saw a max January temp of 40F+. Thats right only 8 years since 1888 has Detroit not hit 40F+ in January. So Detroit has a 93.6% chance of having a max temp of 40F+ in Jan. Those years that didnt hit 40F are: 1912 (max 39F), 1918 (max 36F), 1920 (max 36F), 1977 (max 32F), 1978 (max 37F), 1979 (max 37F), 1985 (max 37F), & 2009 (max 39F).

 

68 of the last 124 years Detroit saw a max January temp of 50F+, so Detroit has a 54.8% chance of having a max temp of 50F+ in Jan.

 

15 of the last 124 years Detroit saw a max January temp of 60F+, so Detroit has a 12.1% chance of having a max temp of 60F+ in Jan.

[Geos]

As long as I can remember there has been at least a hand full of above freezing days in January. January 2001 here only had peak highs in the mid 30s.

 

January of 2009 was almost completely below freezing here. Only 3 days, the 3rd and 4th were 33°, and the 31st was 37°. Mid month was the coldest when the morning of the 16th was -19°.

January 2010 here was mostly below freezing, the 1st was 42°, then there was 3 other days that month that were between 32-35°.

 

So if there was a month were we skipped a thaw in this area it would have been January 2009.

A few 40s are expected every January and then probably every 3 January's 50s can be expected. Near 60 probably every 5-8 years or so.

 

[Ottawa Blizzard]

Toronto almost always gets a big thaw as well, as does Ottawa. The only years I think a thaw wasn't experienced in recent decades were 1994 and 2009. 2007 might also fit in there given the first half of the month was really one big thaw.

 

The biggest thaw I can remember is that of January 1995. It turned so warm around mid month that trees were starting to bud in the city. Winter came back full force after the 20th however, and there was a deep freeze in early February 1995.

[IWXwx]

I just did a very quick analysis for January's at FWA, just using data since 1949 (63 years). 

 

95% hit 40 - 60 years

70% hit 50 - 44 years

27% hit 60 - 17 years

 

With 7 out of every 10 January's hitting 50 or better, the January thaw phenomena is valid at FWA.

[Chicago WX]

Since 1943, when the official location for Indy was moved to the airport, only two Januaries have failed to have at least one max temp of 40º+ (1977 and 1979...Jan 1977 didn't have one day above 31º FYI). Only nine have failed to have one day hit 50º+. Exactly 50% have had at least one day of 60º+. 

 

 

 

 

 

 

[IWXwx]

FWA's 3 years that failed to reach 40 were 1976 (38), 1977 (29) , and 1979 (36).

[michsnowfreak]

I see the abnormality of the cold 1970s winters once again rearing its head. There really is nothing like that stretch in the entire period of record anywhere in this region.

[Ottawa Blizzard]

I see the abnormality of the cold 1970s winters once again rearing its head. There really is nothing like that stretch in the entire period of record anywhere in this region.

 

Which is when people in their 40s were kids, and people in their 50s were in their teens - a huge chunk of the population. Even though I complain, I admit that this is why so many of the middle aged people today say that winters were snowier and colder when they were younger. They were. It's the winters of the 60s, 70s and early 80s that they are remembering.

 

I was born in 1980 and while I remember the occasional cold winter ( 1992-1993, 1993-1994 and 1995-96 for example) comes to mind I also remember winters that didn't see much snow at all. I remember there was no snow for Christmas 1988 and how unhappy I was because I couldn't use the new toboggan I got for Christmas over the holidays.

[Harry]

Which is when people in their 40s were kids, and people in their 50s were in their teens - a huge chunk of the population. Even though I complain, I admit that this is why so many of the middle aged people today say that winters were snowier and colder when they were younger. They were. It's the winters of the 60s, 70s and early 80s that they are remembering.

 

I was born in 1980 and while I remember the occasional cold winter ( 1992-1993, 1993-1994 and 1995-96 for example) comes to mind I also remember winters that didn't see much snow at all. I remember there was no snow for Christmas 1988 and how unhappy I was because I couldn't use the new toboggan I got for Christmas over the holidays.

 

Snow cover played a big role as well as having a few epic bombs between 1967 and 1979. For some yeah it snowed a bit more but for others ( such as this area ) that was not the case. A number of those winters had deep and long lasting snowcover a result of epic bombs or in 76-77 case a very cold winter that did not see much in the way of thaws which allowed the snow pack to get deep. That gave/gives people the impression it snowed more.. I tell people around here it snowed alot more in 2000-2010 then it did in the 1970s and they are taken back/shocked. In the true lake belts ( just to my west ) though it was snowier in the 70s though which is not surprising considering how cold a few of them winters were. yes they were colder ( longer lasting cold too ) but snowier depends on where..

[Trent]

You have to look at this way. The climate of mid latitudes is not of consistent seasonal temperatures as one would find in the tropics for each season. Instead the climate normals for a particular mid latitude city should be something like this for a given day (lets say November):

 

40% of high temps were between 40 and 50

20% of high temps were between 50 and 60

20% of high temps were between 30 and 40

10% of high temps were under 30

10% of high temps were over 60

 

So while the average high may be 45, one can really expect the gamut of temperatures and can expect that within that month they'll probably see a few cool days and few warm days.

 

With that said, it would make sense that nearly every January would have a thaw. That's just typical mid latitude climo. It's the equivalent of finding a summertime "cooldown" where there was a high 8 degrees below normal (~75 and under). It'll happen almost every year.

[michsnowfreak]

Which is when people in their 40s were kids, and people in their 50s were in their teens - a huge chunk of the population. Even though I complain, I admit that this is why so many of the middle aged people today say that winters were snowier and colder when they were younger. They were. It's the winters of the 60s, 70s and early 80s that they are remembering.

 

I was born in 1980 and while I remember the occasional cold winter ( 1992-1993, 1993-1994 and 1995-96 for example) comes to mind I also remember winters that didn't see much snow at all. I remember there was no snow for Christmas 1988 and how unhappy I was because I couldn't use the new toboggan I got for Christmas over the holidays.

 

The PROBLEM is....people have been saying that for hundreds of years, and there is never any merit to it. I have Detroit newspaper articles from 1886, 1954, and 1977 that all take DIRECT potshots at the old-timers claiming winters were much harsher in their day. Its always been that way and always will. In 2030 we will probably have an 80" winter and someone will say "this is nothing like the winters we had when I was your age", which would probably be 2011-12 lol. Theres never any merit to it, just a generic statement. 2000s winters are just as snowy as the 1970s were here, but not nearly as cold. 2000s winters are not quite as cold as the 1960s, but way snowier. 2000s winters are colder AND snowier than the 1950s, and about the same temperature but way, way, WAY snowier than the 1940s. So even then...any simple statement "it was snowier when I was a kid" is wrong. To me it is the widespread COLD of the 3 consecutive winters 1976-77, 1977-78, 1978-79 that is the most impressive thing of all.

[Ottawa Blizzard]

Snowfreak, I did some reserach into Toronto Januaries and came up with some interesting findings that match your's. Most surprisingly, i discovered that the first two decades of the twentieth century actually saw Januaries that were quite mild.  Below are some of my findings. The temperatures listed are the monthly mean temperatures in degrees celcius. I'll post this in the climate change thread too, in case the moderators think it's more appropriate for there. I posted the data here as well given it's relevant to your thread.

 

 

 

 

January 1900: -3.4C

1901: -4.7C

1902: -4.8C

1903: -5.0C

1904: -8.9C

1905: -7.8C

1906 -0.6C

1907: -5.5C

1908: -4.3C

1909: -3.2C

 

1910: -3.6C

1911: -3.4C

1912: -10.1C

1913: -0.3C

1914: -3.6C

1915: -4.6C

1916: -1.0C

1917: -5.2C

1918: -10.5C

1919: -1.5C

 

Now look at the last three decades. It should be noted that the above were recorded in downtown Toronto, while the ones below were recorded at Toronto Pearson airport.

 

1980: -5.1C

1981: -10.2C

1982: -10.1C

1983: -4.1C

1984: -9.7C

1985: -8.4C

1986: -5.6C

1987: -4.6C

1988: -4.5C

1989: -2.2C

 

1990: -0.8C

1991: -5.7C

1992: -4.2C

1993: -3.9C

1994: -12.4C

1995: -3.1C

1996: -6.7C

1997: -6.4C

1998: -2.2C

1999: -6.2C

 

2000: -5.8C

2001: -4.1C

2002: -0.5C

2003: -8.3C

2004: -9.4C

2005: -6.8C

2006: 0.2C

2007: -2.9C

2008:-2.1C

2009: -8.8C

 

2010: -5.2C

2011: -7.0C

2012: -1.7C

 

Note how in the first decade of the 20th century,the only exceptionally cold January was 1904. The others were roughly the same as the Januaries of the 1990s, with January 1906 being just as much of a torch as January 1990. So much for our great-grandparents facing bitter cold winters the likes of which we have never seen. Now look at how mild most of the Januaries of the 1910s were. Many of them were virtual blowtorches, including January 1913, 1914, 1916 and 1919. Only January 1912 and 1918 were frigid.

 

Now look at the late 20th/early 21st century. The Januarys of the 1980s were almost colder than those of the 1900s, with January 1981 and 1982 easily surpassing all of them. As for the 1990s, note how 1994 stands out like a sore thumb. It is the coldest January ever recorded at Toronto Pearson airport and - get this- the coldest January recorded in Toronto since at least 1870!!

 

Finally, look at how in the first decade of this century, the Januaries have slowly trending colder, despite the torches of 2002 and 2006. 2003-2005 saw three cold Januaries in a row, easily the equal of those in the first decade of the 20th century. This decade started out decently cold, with only last January being a torch.

 

All-in-all, it would appear that the Januaries of today are not significantly warmer than those of our grandparents and great-grandparents. I read in a book on Toronto once that "anyone older than 50 can remember a time when the harbour froze regularly and people could skate to the Toronto Islands". Judging from what I've seen in the data (and I've only included a fraction of it in this post) I can't see how it is possible that the harbour regularly froze. If anything, the Januaries of the first two decades of the twentieth century were milder than what we've been experiencing. Granted, one does have to take into effect the different recording stations, with the early twentieth century readings being taken in a downtown location as opposed to the airport.