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Thinking about the Rockies influence in the winter, I just realized these maps made it very clear. Look at the bend in the contours to the east of the Rockies:
The bend is in the shape of a wave (Rossby Wave?), and notice that the coolest temperatures are nearly 1000 miles to the east of the Rockies. The mean max in northern Montana at the base of the Rockies is similar to central Illinois! Mins are a bit less drastic, but similar shape. If the Rockies weren't there, a dramatic bend would be unlikely; the shadings would go west-east. East of the Cascades but west of the Rockies, the climate is milder and the temperatures don't drop as much going east, though it's muddled from elevation. A similar bend in the wintertime map of Canada:
Another comment: the big southward dip in January temperatures is even more unexpected without the Rockies given the elevation changes. As you go east along the Great Plains, the average temperature decreases while the elevation also decreases. But as I showed in the map before, the extreme lows stay roughly the same; the western plains are more variable but on average milder.
Another comment: the big southward dip in January temperatures is even more unexpected without the Rockies given the elevation changes. As you go east along the Great Plains, the average temperature decreases while the elevation also decreases. But as I showed in the map before, the extreme lows stay roughly the same; the western plains are more variable but on average milder.
I agree that as you go east along the Great Plains average "winter" temps decrease (I think it mainly applies to winter)
while elevation also decreases.
Also Canadian Great Plains experiences the same thing.
Here are examples (1981-2010 normals )
Calgary at over 1000 m elevation (about 3,500 ft)
January avg high -0.9c / avg low -13.2c
Regina is at about 600 m elevation
January avg high -9.3c / avg low -20.1c
Winnipeg is at less than 300 m elevation
January avg high -11.9c / avg low -21.4c
Calgary is far milder in January than farther east, even though it's much higher and one degree farther north too!
Being close to the Rockies is beneficial, with warm "Chinook" winds that farther east doesn't enjoy.
Great Lakes has obvious influence, Hudson Bay not as much.
Interesting index. So basically from Chicago points west continentinality increases. Obviously the Great Lake have a much greater impact on the US then the Hudson Bay.
I agree that as you go east along the Great Plains average "winter" temps decrease (I think it mainly applies to winter)
while elevation also decreases.
Also Canadian Great Plains experiences the same thing.
Here are examples (1981-2010 normals )
Calgary at over 1000 m elevation (about 3,500 ft)
January avg high -0.9c / avg low -13.2c
Regina is at about 600 m elevation
January avg high -9.3c / avg low -20.1c
Winnipeg is at less than 300 m elevation
January avg high -11.9c / avg low -21.4c
Calgary is far milder in January than farther east, even though it's much higher and one degree farther north too!
Being close to the Rockies is beneficial, with warm "Chinook" winds that farther east doesn't enjoy.
Also, it seems that places in east of the Rockies are warmer than places west of the Rockies) in terms of both summer and winter means and extremes.
Here are a few cities between 39 & 40 degrees north from different areas of the globe and their January hi/lo:
Ukiah, California - 56/37
Denver, Co - 44/17
Indianapolis, In - 36/20
Valencia, Spain - 61/45
Beijing, China - 35/17
I'd also like to add 3 cities you forgot on your list to complete the picture:
Philadelphia, Pennsylvania - 40/26
Pyongyang, North Korea - 31/13
Akita, Japan - 37/27
Seems like on the Asian mainland, the further east you go, the temp decreases while elevation decreases as well. Pyongyang is colder than Beijing, and also 60 feet lower than Beijing. Akita is the anomaly, no doubt moderated by the Sea of Japan
One thing I find really fascinating about the continental climates in Eastern North America vs. East Asia is the fact that even though latitude for latitude, the continental climates in Asia are colder (sometimes considerably so), the standard deviation from the norm in winter these climates isn't that great.
For example, Shanghai has an average high/low of 47/34F in January and a record low of 10F. Brunswick, GA has an average high/low 63/42 in January which is much warmer on average than Shanghai but has a colder record low at 5F.
It makes sense why Shanghai is colder on average than Brunswick due to the Siberian anticyclone but why does Brunswick have a colder record low? The Siberian anticyclone is much colder and stronger than the North American equivalent. Do the Rockies have something to do with this?
That 5 F temp in Brunswick was caused by a very bizarre and unusual polar outbreak. I wasn't alive at the time, and I don't think it will ever happen again. Even last January's polar event, which brought some of the coldest temps in 10 years to the southeastern US, was far, FAR warmer than what happened in 1985.
That being said, I will say that last winter was the most bizarre winter I've ever seen in my (rather young) lifetime. In December, my area was setting monthly record highs, topping out over 80 F. Then came January, which had numerous nights (and even 1 afternoon high) of sub freezing temps with a winter storm. I know we have variable winters down here depending on the patterns, but what we saw last winter was just ridiculous.
That 5 F temp in Brunswick was caused by a very bizarre and unusual polar outbreak. I wasn't alive at the time, and I don't think it will ever happen again. Even last January's polar event, which brought some of the coldest temps in 10 years to the southeastern US, was far, FAR warmer than what happened in 1985.
That being said, I will say that last winter was the most bizarre winter I've ever seen in my (rather young) lifetime. In December, my area was setting monthly record highs, topping out over 80 F. Then came January, which had numerous nights (and even 1 afternoon high) of sub freezing temps with a winter storm. I know we have variable winters down here depending on the patterns, but what we saw last winter was just ridiculous.
I don't know how old you are, but based on your comment you haven't seen many winters in eastern North America. Last winter pales in comparison to what happened in the 1960's to 1980's. Look at winter of 1963, 1977, 1982, 1985, Nov-Dec 1989, etc. and you will see what we are in store for this winter. Last winter will seem tame in the US South compared to what you are headed for.
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