Notes on lines these pages already print.
°Celsius and °Fahrenheit
The units menu has two entries. °Celsius goes to /u:c,mm,mb,km. °Fahrenheit goes to /u:f,in,in,mi. The degree sign is on the menu word. The path uses a colon after u, then letters and commas, no degree sign.
The London today list is already written in °C, km/h and mm. The note on 16C quotes that list. It does not contain a Fahrenheit conversion.
What the path spells
/u:c,mm,mb,km puts four codes after the colon: c, then mm, then mb, then km. Commas separate them. There are no spaces.
/u:f,in,in,mi puts f, then in, then in again, then mi. The code in appears twice. The page prints that repetition. It does not explain the two ins in the menu.
The visible menu does not spell mm, mb, km, in or mi. It spells °Celsius and °Fahrenheit. The codes are in the addresses. Both are on the front page, the word in the menu and the code in the href.
Those two addresses are not city pages. They are not /en/united-kingdom/london. The note on the front page is about London. This note is about the two hrefs in the units menu.
c, mm, mb and km are four codes. f, in, in and mi are four codes too, with in repeated. The menu does not spell those codes. The addresses do.
No degree sign sits inside either path. The degree sign is only on the visible menu words °Celsius and °Fahrenheit.
What the London list already uses
16°C and 6°C use a degree sign and C. The sentence says 16C without the sign. Wind is in km/h. Precipitation is in mm. Pressure, in the current block, is 1031.2 mbar.
The Celsius path writes mb. The pressure line writes mbar. The page uses both spellings, in two places: mb inside the path, mbar next to 1031.2. The note does not change either.
km in the path and km/h in the wind line share the letters km. The wind line adds /h. The path does not write /h.
mm in the path and 0 mm in the precipitation line share mm. The list writes a space before mm. The path writes mm against the comma.
The list writes km/h, the path writes km. The list writes mbar on the pressure line, the path writes mb. The list writes a space before mm.
Humidity is a percent on the list, and neither path carries a percent sign. UV index 3 is an integer on the list, not a code in the address.
No Fahrenheit figure in the today block
The today block does not print a °F number beside 16°C. The current block does not print one beside 15°C or 13°C. The menu offers the Fahrenheit address. The forecast lines that this note quotes stay in the C spelling.
High 16C is closer to a bare C than to °Fahrenheit. It is still the letter C. It is not the letter f from the other path.
The front page does not show a converted pair. It shows a menu. The London page shows a list already in °C, km/h, mm and mbar.
UV index 3 and humidity 48% and probability 10% do not use c, f, mm or km. They sit in the same list. The note on the Friday heading includes those lines with the date. This note only asks which unit codes the menu and the list use.
No °F number sits beside 16°C, 15°C or 13°C. High 16C is still the letter C.
The Fahrenheit path is a menu address, not a second set of figures on the today block.
Where the menu sits
The units menu is labelled Units. It is a dropdown, in the same bar as Languages and as the links Cities and Climate. Cities goes to /en/united-kingdom. Climate goes to /en/united-kingdom-climate. Units goes to the two u: paths. Three menus, three kinds of address.
The language paths are /de, /en, /es, /ru and /zh. The unit paths both start with /u: and then a comma-separated code. They are not language codes.
The note on the language labels quotes deutsche and the rest. Those words are not units. °Celsius and °Fahrenheit are not languages. They share a bar.
The search form is another control in that header. It posts to /en/search.php. It is not a unit switch. The placeholder names a country, not a unit.
Cities, Climate and Units are three controls. Languages is a fourth. Search is a form, not a unit switch.
The placeholder reads United Kingdom - search location. It names a country. The two unit addresses name codes, and the form does not. Units stays a dropdown.
The addresses as they stand
Opening the unit addresses does not add a Fahrenheit copy of the 16°C line to this note. The menu text and the path codes are the printed fact. The London list is the other printed fact. They disagree in small ways: mb against mbar, km against km/h, and a degree sign in the menu word but not in the path.
in is repeated in /u:f,in,in,mi. The London list does not print the word inch. It prints mm. The repetition stays in the path.
c and f are single letters. °Celsius and °Fahrenheit are the long menu words. The page uses the long word where the reader clicks, and the short codes in the address.
Nothing in these two paths is a place name. London, Edinburgh, Birmingham and Presteigne are place pages. The note on those titles does not run their temperatures through a unit conversion. The unit fact is the menu and the path.
The long menu words are °Celsius and °Fahrenheit. The paths keep the short codes and the commas.
Questions
What does the Celsius path contain?
/u:c,mm,mb,km. The menu word is °Celsius. The path has no degree sign.
Why does in appear twice?
Because the Fahrenheit address is /u:f,in,in,mi. The page prints in twice. It does not gloss the two ins.
Does the London today list say mbar or mb?
The pressure line says 1031.2 mbar. The Celsius path says mb. Both spellings are on the site.