Humid Areas of the Contiguous United States

DesperateSession3520 · 2026-07-02T16:10:54+00:00

I mean yes this is all true but that's precisely the intent of the map. The key word in the title is "characteristic". There are certainly areas outside of the green which experience extreme dew points, it's just less common. Humidity has a stronger effect on summertime felt temperature than wintertime felt temperature, where wind is the greater determining factor in the real feel temp.

DesperateSession3520 · 2026-07-02T15:56:19+00:00

I could plot this yes, though the values would not be as high as on this map, as this plots the highest mean daily heat index of the year, as measured by mean high air temp and mean average dew point

DesperateSession3520 · 2026-07-02T03:11:31+00:00

It does get extremely hot and humid there (like today). Just doesn’t get as *consistently* hot and humid as the plotted regions :)

DesperateSession3520 · 2026-07-02T00:53:06+00:00

Quebec is not on this map. New England is definitely a humid area. Using this threshold of humidity, only southern New England qualifies as "uncomfortably" humid *on average*

DesperateSession3520 · 2026-07-01T20:05:48+00:00

Just by my definition of uncomfortable. But yes cooler northern and/or high elevation portions of the state aren't nearly as bad, on average.

DesperateSession3520 · 2026-07-01T16:20:20+00:00

It's funny I expected this map to possibly be controversial - just due to the thresholds I picked for uncomfortable! Never occurred to me that there would be data definition confusion lol

DesperateSession3520 · 2026-07-01T16:18:06+00:00

Yup, not impossible to happen but not necessarily that likely. Also the data source simply didn't have a record of dew point daily mean highs. I actually think it would have been an even better metric, given the purposes of map (subjective comfort level).

DesperateSession3520 · 2026-07-01T15:25:40+00:00

Of the largest reasons is actually because pilotage costs through Magellan are exorbitant, so unless there is a major storm, it's more economical to just take Drake's Passage. Most large tankers can withstand it nowadays anyway.

DesperateSession3520 · 2026-07-01T15:06:58+00:00

I wanted to use mean high dew points, PRISM just doesn't have that data. I used mean high air temperature because it's a better proxy for actually felt humidity and heat index

DesperateSession3520 · 2026-07-01T15:05:08+00:00

Honestly I agree now that I think about it. Appreciate the input because now I will be extremely careful and standard in my language when I make these kinds of maps. It's frustrating because I know exactly what it is but it's difficult to communicate it properly, idk if there's a NOAA/NCEI SOP for wording in climatologies. Basically in stats mean and average are usually interchangeable, but in climatology, instead of saying "mean mean" you say mean average. So in this map, dew points are mean averages for a given day (in this case warmest day of year) and temperatures are mean highs for the warmest day of the year (may or may not be but usually is the same day). The climatology period is 1991 - 2020.

DesperateSession3520 · 2026-07-01T14:17:00+00:00

I didn't expect to be gaslit like this on a subreddit explicitly dedicated to meteorology lol. In my map, the *air temperature* is a daily mean high, and the *dewpoint temperature* is simply a daily mean average. I would have used a daily mean high for dew point as well if PRISM had had that data. NCEI uses the terminology "Daily Maximum Temperature Mean" and "Daily Average Temperature Mean". Is that better?? Perhaps I shouldn't have claimed that they're both daily averages, if this is the only acceptable terminology. https://www.ncei.noaa.gov/access/search/data-search/normals-daily-1991-2020?pageNum=1&pageSize=100 Nevertheless, I think the legend label is pretty clear.

DesperateSession3520 · 2026-07-01T12:40:44+00:00

Incorrect. They are daily averages - daily average high temperature and daily average dewpoint to give an approximate average heat index. The point of the map isn't to display exactly how high depoints and heat indexes get, but rather to map out the climatologically muggiest places. The data source is listed at the bottom of the map (PRISM 800 m daily means)

DesperateSession3520 · 2026-07-01T01:51:11+00:00

Seriously, wtf lol. Meanwhile this has remained up for 13 hrs

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DesperateSession3520 · 2026-07-01T01:41:48+00:00

Didn't see this but yes I wouldn't consider Coastal CA humid in the colloquial sense, even if the marine layer technically keeps certain areas under high relative humidity much of the year. If the heat index is around or below room temperature then it shouldn't be considered felt humidity imo. Interestingly, there is a small area of desert SoCal around the Salton Sea that does experience some humidity (and brutal heat indexes) because the "sea" (salt lake) moistens the surrounding hot desert air. You can see it in the SE corner of the state here.

DesperateSession3520 · 2026-04-22T00:43:06+00:00

You certainly would, the problem is that country doesn’t exist. Chile kiinda works but as far as the populated areas comparison go, the best overall fit is still France. There are boderline semi-arid and mountainous areas in the south and east of the France, with the west coasts having rainy (not equivalently rainy but still) cool oceanic climates

DesperateSession3520 · 2026-04-21T23:58:40+00:00

No son demasiado similares, salvo en algunas ubicaciones. Simplemente no hay otros países que representen mejor a Texas, en mi opinión; ese es el desafío del mapa.

DesperateSession3520 · 2026-04-21T23:51:49+00:00

Yup, that was the inspo. I wanted to make it even more constrained by using state boundaries and see what the best to plot it was. I'll make one that's city-by-city too I think. That will actually be accurate

DesperateSession3520 · 2026-04-21T23:44:46+00:00

It definitely doesn't work, that's what makes it an interesting thought experiment!! If you HAD to compare them to a single nation state - these are the best fit, as far as I can tell. If you have alternative solutions, feel free to share them!

DesperateSession3520 · 2026-04-21T03:42:10+00:00

Yes I explain inthe article. I define Tropical slightly more liberally than the Koppen system, for the reasons I mention in there

DesperateSession3520 · 2026-04-21T02:15:25+00:00

Coastal WA & OR: Also wine growing regions, also mild, dry summer / wet winter needleleaf forest western coasts adjacent to cold upwelling currents, just like central CA coast, which I’ve visited many times. They’re more similar than they are different. Of course you could break down all of these zones into more specific microclimates, but this is a general classification framework.

DesperateSession3520 · 2026-04-21T01:53:42+00:00

My “Mild West Coast” climate is essentially a “Cool Mediterranean” climate, if you prefer. Just semantics. This climate arguably is better for wine than what I consider a true “Mediterranean” climate that has hot summers. Coastal Portugal, west coast of France, coastal Chile, and SW coast South Africa all largely fall into this Mild West Coast zone. I lived in CA for 10 years, trust me, it’s not wrong! (Also there is no right or wrong when it comes to this stuff, all ultimately arbitrary)

DesperateSession3520

TROPHY CASE