Hottest & Coolest Summer Cities

[memph]

Originally Posted by eschaton

I'd be interested in seeing this reformulated with a "heat index" for the warmest month instead. Given most of the hottest cities are in arid climates - and have low humidity - I'd expect they are actually more tolerable than some of the less hot but humid cities.

This city is probably a strong contender...


Those are heat indices ranging from 124-135F.

[iheartthed]

Originally Posted by memph

There's certainly plenty of large Chinese cities well north of Beijing that are more extreme.

Yeah, I don't know Chinese cities well enough to name any beyond the really big ones. But I figured the winner would be somewhere in the northeastern quadrant of China.

[memph]

Originally Posted by iheartthed

Yeah, I don't know Chinese cities well enough to name any beyond the really big ones. But I figured the winner would be somewhere in the northeastern quadrant of China.

It's easy to forget how big China is. From Hainan Island to the Amur River is about 3900 km, which is the same distance as Key West to the middle of the Hudson Bay. But Northern China is still pretty heavily inhabited compared to Northern Ontario/Quebec/Manitoba, etc. It's not much of a comparison between Thompson, Fort McMurray, Grande Prairie, Moosonee, Labrador City and Fort Nelson vs Harbin, Qiqihar, Changchun, Jilin, Daqing and Mudanjiang. The Chinese cities do have rather long and warm summers though which helps. Their summers are about on par with New England or Upstate NY, rather than Abitibi's (which has the comparable winters).

Harbin and Changchun are only about 3-4m urban areas, ranking outside China's top 30, so you can be forgiven for not knowing them. Shenyang isn't as cold, with a January mean of -11C, though that's still 8C colder than Beijing, and it has 8m (ranked 14th in China).

[jmecklenborg]

I got in the ocean this past weekend in South Carolina. It felt like bath water. I checked the ocean temperature online and it's 86.5F.

At night, when the air temperature dips a little below that of the ocean, you really feel its energy. There's almost a tension in the air since a red carpet has been rolled out for hurricanes to make their way over from Africa.

[eschaton]

Originally Posted by memph

It's easy to forget how big China is. From Hainan Island to the Amur River is about 3900 km, which is the same distance as Key West to the middle of the Hudson Bay. But Northern China is still pretty heavily inhabited compared to Northern Ontario/Quebec/Manitoba, etc. It's not much of a comparison between Thompson, Fort McMurray, Grande Prairie, Moosonee, Labrador City and Fort Nelson vs Harbin, Qiqihar, Changchun, Jilin, Daqing and Mudanjiang. The Chinese cities do have rather long and warm summers though which helps. Their summers are about on par with New England or Upstate NY, rather than Abitibi's (which has the comparable winters).

Harbin and Changchun are only about 3-4m urban areas, ranking outside China's top 30, so you can be forgiven for not knowing them. Shenyang isn't as cold, with a January mean of -11C, though that's still 8C colder than Beijing, and it has 8m (ranked 14th in China).

Aside from being more arid, China's climate is closer to Eastern North America than anywhere else on Earth. Which makes sense, considering they're both on the eastern side of continents in the northern hemisphere.

[lio45]

When you’re used to the ocean being bath water, it spoils cooler water for you. I used to be able to swim in Canada or Old Orchard (Maine) and enjoy it, not anymore.

On the other hand, I’m not looking forward to the hurricane season :/

[JManc]

Originally Posted by lio45

When you’re used to the ocean being bath water, it spoils cooler water for you. I used to be able to swim in Canada or Old Orchard (Maine) and enjoy it, not anymore.

On the other hand, I’m not looking forward to the hurricane season :/

Yup. I can do the Gulf in Galveston even though it's murky and nasty, it's warm. I now live within an hour of the Pacific and there's no way I'm going into the water.

I don't know if people go into the SF Bay itself but I'd imagine that's equally frigid.

[memph]

Originally Posted by lio45

When you’re used to the ocean being bath water, it spoils cooler water for you. I used to be able to swim in Canada or Old Orchard (Maine) and enjoy it, not anymore.

On the other hand, I’m not looking forward to the hurricane season :/

Not even smaller lakes or Lake Erie? Lake Erie is in the high 70s in August. Currently 77F. Last year it peaked at 78.5F in late August, we'll see this year.

I've only been to Florida in November and April when the water temperatures were about the same so I guess I haven't experienced the bath-tub temperatures.

[memph]

Originally Posted by JManc

Yup. I can do the Gulf in Galveston even though it's murky and nasty, it's warm. I now live within an hour of the Pacific and there's no way I'm going into the water.

I don't know if people go into the SF Bay itself but I'd imagine that's equally frigid.

Water temperatures in California peak at similar temperatures as in Lake Superior where I'll go swimming in August. It's not really suitable for lazing around in the water, but if you're swimming more energetically or if you're only waist deep tossing a frisbee it's fine.

[JManc]

Originally Posted by memph

Not even smaller lakes or Lake Erie? Lake Erie is in the high 70s in August. Currently 77F. Last year it peaked at 78.5F in late August, we'll see this year.

I've only been to Florida in November and April when the water temperatures were about the same so I guess I haven't experienced the bath-tub temperatures.

Lake Erie is pretty shallow.

[harls]

I have a Canadian question for people in Phoenix - is it a given your car will be in a garage all of the time when you are not using it?

The sun will not murder my interior if I leave it outside for a Quebec summer.

[memph]

Originally Posted by eschaton

I'd be interested in seeing this reformulated with a "heat index" for the warmest month instead. Given most of the hottest cities are in arid climates - and have low humidity - I'd expect they are actually more tolerable than some of the less hot but humid cities.

I was able to find the relative humidity for the morning and afternoon for US cities, so I can calculate the average daily peak heat index for the warmest month. Only exception are McAllen and Sarasota which historic humidity averages aren't available for so I used Brownsville and Fort Myers instead. Also San Jose doesn't have humidity data (that I could find) so I just made an educated guess based on what nearby cities are like, but even if my guess is off it doesn't really matter since the temperatures are low enough that the heat index will be barely higher than the temperature.

[iheartthed]

Originally Posted by memph

Not even smaller lakes or Lake Erie? Lake Erie is in the high 70s in August. Currently 77F. Last year it peaked at 78.5F in late August, we'll see this year.

I've only been to Florida in November and April when the water temperatures were about the same so I guess I haven't experienced the bath-tub temperatures.

I'm actually surprised Erie isn't much warmer than that. The water temp off of the Rockaways in Queens is 77F today. I would've expected the water in Lake Erie to be more like Florida at this time of the year.

[memph]

This is the bottom tier of US cities, and the month during which they reach their peak heat index. In case of a tie, I broke the tie based on the warmest low temperature.



Chicago's average afternoon relative humidity is 55% vs New York City's 54%, which combined with a 0.2C warmer daily high gives it a hotter average high heat index (despite cooler nights & daily means).

I also didn't realize the California coast was actually fairly humid, similar to the Great Lakes/Northeast with afternoon humidity levels of around 55%, not just San Francisco but Los Angeles and San Diego too.

[memph]

Originally Posted by iheartthed

I'm actually surprised Erie isn't much warmer than that. The water temp off of the Rockaways in Queens is 77F today. I would've expected the water in Lake Erie to be more like Florida at this time of the year.

Well the mean temperatures for the cities around Lake Erie only peak around 73-74F, and although it's the shallowest of the Great Lakes, it's still deeper than the typical small lake in cottage country.

This was the past year - it was still very cold until late April (equally cold to late December).

Aug 28: 78.5F (peak)
Sep 22: 70.7F
Oct 29: 60.3F
Nov 22: 50.2F
Jan 5: 40.1F
Jan 31: 32.4F (low)
Mar 7: 32.4F (low)
Apr 13: 40.2F
May 12: 50.9F
May 29: 60.2F
Jul 2: 70.2F
Aug 7: 77.4F
Aug 12: 76.4F

[memph]

Mid tier of US city heat indexes.

[memph]

Texas and its high humidity dominates the list of muggiest American cities.

US Cities with highest average high heat indexes during their warmest month:

[Quixote]

Originally Posted by memph

Among US controlled territories...

For bigger cities, San Juan and Honolulu would both have a more uniform climate than San Francisco.

Variance:

Los Angeles: 19.9C
Miami: 16.5C
San Diego: 15.3C
San Francisco: 13.1C
Honolulu, HI: 12.3C
San Juan, PR: 9.7C

Smaller communities/minor outlying islands
Ketchikan, AK: 20.3C
Ocean Shores, WA: 16C
Coos Bay, OR: 15.6C
Monterey, CA: 14.2C
Key West: 14C
Eureka, CA: 13.4C
Midway Atoll: 12.1C
San Nicolas Island, CA: 11.6C
St Thomas, US Virgin Islands: 10C
Wake Island: 8.9C
Guam: 7.7C
Johnston Atoll: 7.5C
Saipan, Northern Marianas Islands: 6.7C
Palmyra Atoll: 5.6C

Honorable mention: Oxnard, CA (variance of 15.3C)

Probably the best weather on Earth in terms of “comfort” IMO. Milder than SD during the height of summer (average high of 72.9F and 73.5F in July and August, respectively) but warmer than “freezing” SF. The average low is in the mid to high 40s in December through March, giving you a little bit of a “taste of winter.”

[craigs]

Originally Posted by memph

Water temperatures in California peak at similar temperatures as in Lake Superior where I'll go swimming in August. It's not really suitable for lazing around in the water, but if you're swimming more energetically or if you're only waist deep tossing a frisbee it's fine.

Water temp at the beach in San Diego this week was 73 degrees. I thought it was great, but some people prefer bathwater.

Originally Posted by memph

I also didn't realize the California coast was actually fairly humid, similar to the Great Lakes/Northeast with afternoon humidity levels of around 55%, not just San Francisco but Los Angeles and San Diego too.

On either Monday or Tuesday (can't remember which) it was 80-something degrees and 68% humidity in downtown San Diego.

[Buckeye Native 001]

^That sounds miserable, but I forget that dew point and barometric pressure plays a role. If it wasn't raining or on the verge of raining, my experience has been that the humidity isn't always super noticeable unless you're doing strenuous activity. Downtown San Diego's right on the water, but a few miles inland and it can feel a lot drier.

Then again, having lived in Arizona and inland Orange County, the humidity in South Florida knocked me on my ass the first time I visited.

Originally Posted by harls

I have a Canadian question for people in Phoenix - is it a given your car will be in a garage all of the time when you are not using it?

The sun will not murder my interior if I leave it outside for a Quebec summer.

Shade is a precious commodity in Arizona. Garages are ideal but if and when covered parking isn't available, I've parked near or under trees far away from store entrances if it means getting even a little bit of shade.

Window sun screens and steering wheel and dashboard covers are a necessity if you care at all about the interior of your car. Most vehicles purchased in Arizona (even mine, a 2008 Honda) come with some form of window tint to help mitigate sun damage, but its still blazing hot. Even in Flagstaff when the high is in the mid to upper 70s Fahrenheit, any length of time in the sun can make my car feel 20 degrees hotter on the inside. Most of my car's interior is cloth (and plastic...) but god help anyone with leather or vinyl interiors in Phoenix during the summer months.

The other issue isn't rust like back east, but paint oxidation. Cars here will run forever without rust, but after enough time in the sun, the paint will fade and primer gray will begin to show. My car is silver so its hard to tell if the paint is fading, but I only had it for a year and a half when I lived in Phoenix before moving north where most of the time its either parked under a car port at home or at work. Its not unusual to see a lot of cars seven or eight years or older to have fading paint or oxidation if they're not garaged.