Constitution MapNine patterns · 14 US cities

Climate reading

Denver and the Chinese solar calendar

Denver gets 151 freeze-free days a year, and the median first freeze falls on October 6. The fortnight the calendar calls Frost’s Descent opens on 23 October — after the frost has already come. Rain and heat do move together here (r = 0.65), much as they do in the calendar’s home climate (r = 0.88) — on this one axis the seasonal picture carries over.

The station this page reads from

Weather stationDenver Intl, CO
Station IDUSW00003017
Freeze-free days / year151
Median first freezeOctober 6
Median last freezeMay 6
Rain vs. heatr = 0.65 (aligned)
Normals period1991–2020

NOAA NCEI 1991–2020 U.S. Climate Normals. A normal is a thirty-year average, not a forecast and not any single year’s weather.

Right now

Rain and heat across the whole year

Rainy days and heat move together where you are (r = 0.65), as they do in the prototype (r = 0.88) — on this one axis the classical seasonal picture transfers.

Where the calendar is most wrong about Denver

Of the twenty-four fortnights, these four are the ones whose name or advice sits furthest from what Denver’s weather station actually recorded over thirty years.

Cold Dew 寒露from 2026-10-08

Pentads: 鸿雁来宾 · 雀入大水为蛤 · 菊有黄华

containment and levelling (容平 róng píng). Go to bed early and rise early, up with the rooster.

This is the response to autumn qi — the way of nourishing the gathering-in (養收). Going against it is said to injure the lung, so that winter brings undigested diarrhoea and there is less to carry the storing.

Su Wen, 'Four Qi Regulate the Spirit' (素問·四氣調神大論); pentads from the Yue Ling Qi Shi Er Hou Ji Jie

Average / low / high51.4°F / 37.2°F / 65.5°F
Days with measurable rain17.0%
Days at or below freezing4.5
Daylight11h 23m (-40 min from two weeks ago)
  • This fortnight's advice was written for a place averaging 59.0°F at this point in the year. At Denver Intl, CO the 1991–2020 average is 51.4°F — cooler by 7.6°F.
  • 'Cold Dew' is a phenological marker from the Yellow River valley — what observers saw, not a temperature threshold. The nearest thing your own record has to it: at Denver Intl, CO the first freeze of autumn has arrived by October 6 in half of years — 2 days before this fortnight begins. This fortnight typically carries about 4.5 days at or below freezing.
  • This is the fastest-cooling fortnight of your year: 7.1°F below the one before it.

If Yin deficiency came out high for you. Traditional theory associates Yin deficiency with internal dryness and a sense of heat from within. That is a theoretical association drawn from the classical literature, not a research finding. Your average high this fortnight is 65.5°F, and 17.0% of days typically see measurable rain. Whether any of it matters for you is something to observe, not something this page can tell you.

Minor Snow 小雪from 2026-11-22

Pentads: 虹藏不见 · 天气上升地气下降 · 闭塞而成冬

closing and storing (閉藏 bì cáng). Go to bed early and rise late — wait for the sunlight. Leave the cold, stay near warmth, and do not let the skin sweat open.

This is the response to winter qi — the way of nourishing the storing (養藏). Going against it is said to injure the kidney, so that spring brings weakness and collapse and there is less to carry the bringing-forth.

Su Wen, 'Four Qi Regulate the Spirit' (素問·四氣調神大論); pentads from the Yue Ling Qi Shi Er Hou Ji Jie

Average / low / high34.4°F / 21.4°F / 47.4°F
Days with measurable rain15.4%
Days at or below freezing12.5
Daylight9h 44m (-27 min from two weeks ago)
  • This fortnight's advice was written for a place averaging 40.6°F at this point in the year. At Denver Intl, CO the 1991–2020 average is 34.4°F — cooler by 6.2°F.
  • 'Minor Snow' is a phenological marker from the Yellow River valley — what observers saw, not a temperature threshold. The nearest thing your own record has to it: at Denver Intl, CO the first freeze of autumn has arrived by October 6 in half of years — 47 days before this fortnight begins. This fortnight typically carries about 12.5 days at or below freezing.

If Yang deficiency came out high for you. Traditional theory associates Yang deficiency with feeling the cold sooner than the people around you. That is a theoretical association drawn from the classical literature, not a research finding. Your average low this fortnight is 21.4°F, and about 12.5 days typically fall to freezing or below. Whether any of it matters for you is something to observe, not something this page can tell you.

Major Snow 大雪from 2026-12-07

Pentads: 鹖鴠不鸣 · 虎始交 · 荔挺出

Same seasonal passage as above — the classical text gives one instruction per season, not one per fortnight.

Average / low / high30.9°F / 18.2°F / 43.7°F
Days with measurable rain14.8%
Days at or below freezing14.1
Daylight9h 26m (-18 min from two weeks ago)
  • This fortnight's advice was written for a place averaging 36.3°F at this point in the year. At Denver Intl, CO the 1991–2020 average is 30.9°F — cooler by 5.4°F.
  • 'Major Snow' is a phenological marker from the Yellow River valley — what observers saw, not a temperature threshold. The nearest thing your own record has to it: at Denver Intl, CO the first freeze of autumn has arrived by October 6 in half of years — 62 days before this fortnight begins. This fortnight typically carries about 14.1 days at or below freezing.

If Qi stagnation came out high for you. Traditional theory associates Qi stagnation with mood that moves with the season; the classical texts tie autumn's gathering-in to it in particular. That is a theoretical association drawn from the classical literature, not a research finding. Daylight at your latitude is 9h 26m, down 18 minutes from two weeks ago. Whether any of it matters for you is something to observe, not something this page can tell you.

Frost's Descent 霜降from 2026-10-23

Pentads: 豺祭兽 · 草木黄落 · 蛰虫咸俯

Same seasonal passage as above — the classical text gives one instruction per season, not one per fortnight.

Average / low / high45.5°F / 31.6°F / 59.5°F
Days with measurable rain16.6%
Days at or below freezing7.2
Daylight10h 45m (-38 min from two weeks ago)
  • This fortnight's advice was written for a place averaging 53.4°F at this point in the year. At Denver Intl, CO the 1991–2020 average is 45.5°F — cooler by 7.9°F.
  • 'Frost's Descent' is a phenological marker from the Yellow River valley — what observers saw, not a temperature threshold. The nearest thing your own record has to it: at Denver Intl, CO the first freeze of autumn has arrived by October 6 in half of years — 17 days before this fortnight begins. This fortnight typically carries about 7.2 days at or below freezing.

If Damp-heat came out high for you. Traditional theory associates Damp-heat with damp and heat arriving together, rather than either one alone. That is a theoretical association drawn from the classical literature, not a research finding. This fortnight runs to an average high of 59.5°F with rain on about 16.6% of days. Whether any of it matters for you is something to observe, not something this page can tell you.

All twenty-four fortnights at Denver

Fortnight BeginsAvg °FRainy days %Freezing daysvs. calendar °F
Minor Cold小寒2026-01-0531.813.814.0-1.3
Major Cold大寒2026-01-2031.615.613.9-2.4
Start of Spring立春2026-02-0431.718.012.6-6.6
Rain Water雨水2026-02-1835.119.213.8-7.7
Awakening of Insects惊蛰2026-03-0540.620.111.2-7.4
Spring Equinox春分2026-03-2044.823.610.7-9.0
Pure Brightness清明2026-04-0547.028.36.6-11.8
Grain Rain谷雨2026-04-2050.331.15.2-14.3
Start of Summer立夏2026-05-0556.032.61.5-11.6
Grain Buds小满2026-05-2162.132.11.0-10.2
Grain in Ear芒种2026-06-0567.329.00.0-9.2
Summer Solstice夏至2026-06-2172.125.90.0-6.9
Minor Heat小暑2026-07-0775.326.10.0-4.8
Major Heat大暑2026-07-2375.427.50.0-5.9
Start of Autumn立秋2026-08-0773.225.00.0-5.1
End of Heat处暑2026-08-2370.221.30.1-4.6
White Dew白露2026-09-0765.519.80.4-3.0
Autumn Equinox秋分2026-09-2358.518.22.3-5.4
Cold Dew寒露2026-10-0851.417.04.5-7.6
Frost's Descent霜降2026-10-2345.516.67.2-7.9
Start of Winter立冬2026-11-0740.015.811.3-6.6
Minor Snow小雪2026-11-2234.415.412.5-6.2
Major Snow大雪2026-12-0730.914.814.1-5.4
Winter Solstice冬至2026-12-2230.813.813.2-3.0

‘vs. calendar’ is this fortnight’s local average minus the average where the calendar was written. Rain figures on this page count rainy days, not inches. The two can point opposite ways — summer storms drop more water on fewer days.

Find out which patterns are yours

This page describes a place. The assessment describes a person — twenty-five questions, three minutes, nothing uploaded.

Start the assessment

The other thirteen cities