September Weather Lore:17 Sayings From the Almanac Archive
There are a lot of weather lore sayings surrounding the month of September. How many of these have you heard?
Quick Reference
- What September lore is about: harvest, the first frost, the rainfall pattern, and what the month tells you about the winter ahead.
- Most-cited sayings: “September warm, winter warm.” “First snowfall comes six weeks after the last September thunderstorm.” “As September 6, so the next four weeks.”
- The saint days: September 8 (Mary’s Birth), September 9 (St. Gorgonius), September 14 (Holy Cross), September 22 (St. Maurice), September 29 (Michaelmas). Each carries its own forecast lore.
- Key transition signal: Michaelmas (September 29) is the traditional date the heat leaves and autumn settles in across most of the temperate Northern Hemisphere.
- How accurate is it? The fixed-date sayings are folklore. The pattern-based ones (warm September correlating with mild winter, dry September following wet May) have weak but measurable climate correlation.
September is the month most farm calendars treat as the gateway to autumn. The leaves begin to turn, harvest accelerates, and the year’s first frost is suddenly a real concern in the northern tier. Long before climate models and seasonal outlooks, farmers and weather-watchers paid close attention to September’s daily patterns and folded the year-after-year observations into proverbs that have been passed down for centuries. Many of the sayings tie September weather to winter outcomes, harvests, or saint-day calendars. Some of them turn out to have weak but measurable climate correlations. Others are pure folklore. Here is the September weather lore from the Farmers’ Almanac archive, organized into the sayings worth remembering.
General September Weather Sayings
The most-recited September weather sayings, collected across English-language farm almanacs from the 1700s onward:
- “Whatever July and August do not boil, September cannot fry.” If the high heat of mid-summer has not arrived by August, September will not deliver it. The saying captures the seasonal cooling pattern correctly: by mid-September, the average daily high in most of the U.S. has dropped 5 to 10 degrees F from August.
- “As September, so the coming March.” The premise is that September weather mirrors the following March. The science offers some support: a warm dry September often follows a similar atmospheric setup that will produce a warm dry March. The correlation is weak but consistent.
- “Fair on the first of September, fair the entire month.” A clear-weather start is read as a forecast for a clear month. The science is mixed; clear high-pressure systems that produce a clear September 1 do tend to persist for several weeks at a time, but full-month forecasts from a single morning are not reliable.
- “If the storms in September clear off warm, all the storms of the following winter will be warm.” A read on the air-mass character behind September systems. Mostly folklore, with no clear scientific backing.
- “When September has been rainy, the following May is generally dry. When May is dry, September is apt to be wet.” A weak inversion pattern between spring and fall precipitation. Some U.S. climate records show partial support, but the correlation is too weak to function as a usable forecast.
- “Thunder in September indicates a good crop of grains and fruits the next year.” September thunderstorms often deliver useful late-season rain that benefits grain ripening and fruit set for the following spring. The saying captures a real agricultural pattern.
The First-Snow Rule
One of the most-cited September lore items is the first-snowfall rule: “the first snowfall comes six weeks after the last thunderstorm of the month.”
The rule has a real meteorological basis. The last September thunderstorm typically marks the end of summer-style convection in any given location. Six weeks later, the same air mass is cool enough to support snow events. For most of the temperate U.S., a last September thunderstorm on September 25 puts the first snow around November 6, which is a reasonable mean date for first snow across the Upper Midwest, Northeast, and Mid-Atlantic.
The rule does not work everywhere. The Pacific Northwest sees few September thunderstorms but does see snow. The Deep South sees both regularly but in patterns that do not follow the six-week rule cleanly. Use it as a regional rule of thumb for the temperate eastern U.S., not as a universal forecast.
Saint-Day Forecasts
September lore includes several saint-day-anchored forecasts inherited from European Catholic tradition. Each carries its own short window:
- September 6 (no specific saint, just the day): “As the weather is on September 6, so it will be for the next four weeks.”
- September 8 (Birth of the Virgin Mary): “As the weather is on the day of Mary’s Birth, so it will be for four weeks.”
- September 9 (St. Gorgonius): “If the weather is fine on St. Gorgonius’s Day, it will continue fine for forty days.” A long-window read.
- September 14 (Holy Cross / Exaltation of the Cross): “No rain on the Holy Cross, no rain for six weeks.” A drought-prediction saying. “If it rains, there will be a lot of bad October weather.”
- September 19 (no specific saint): “If on September 19 there is a storm from the south, a mild winter may be expected.” A wind-direction read.
- September 22 (St. Maurice): “If there is clear weather on St. Maurice’s Day, heavy winds will rage in the following winter.” A counter-intuitive inversion read.
- September 29 (Michaelmas / St. Michael): “On Michaelmas Day, the heat leaves us.” The traditional first-day-of-fall transition date in pre-modern European calendars. “If St. Michael brings many acorns, Christmas will cover the fields with snow.” A heavy acorn-fall reading: the trees are provisioning for a hard winter.
The saint-day sayings are folklore. None has rigorous climate-science support. They survived because the dates served as memorable anchor points in agricultural calendars; “Michaelmas” is much easier to remember than “September 29 in the modern Gregorian calendar,” especially for an illiterate medieval farm population. The sayings function as much as date markers as they do as forecasts.
Why September Has So Much Weather Lore
Three reasons September accumulated more lore than most other months:
- Harvest pressure. September is when most temperate-climate grain, fruit, and vegetable harvests run at peak. Farmers paid extreme attention to weather in this month because a bad September could erase a whole year’s work.
- Transition month. The shift from summer to autumn is more dramatic than any other seasonal transition (more so than winter to spring, which tends to be gradual). The sharp pattern change provides clear signals.
- Winter preparation window. Whatever a farmer guessed about winter had to translate into action by Michaelmas: stores laid up, livestock brought in, fields readied. Sayings that helped predict winter from September were directly actionable.
The result is a set of sayings that range from sharp weather observation to folkloric anchor-point reminders. Reading them today, the value is partly nostalgic and partly genuine. The pattern-based observations (warm September following a warm spring, harvest signals in early frost) hold up better than the saint-day specifics. The whole collection is part of a larger seasonal vocabulary that has shaped how rural Americans think about the autumn for two centuries.
How to Use September Lore Today
For the modern reader, September weather lore is most useful as a layered signal alongside a real seasonal forecast. A few practical applications:
- Watch the last September thunderstorm. If you live in the temperate eastern U.S., note the date. Six weeks later is a reasonable rough estimate for first snow in your area.
- Note the September overall pattern. If September runs warmer than average, the saying “as September, so coming March” suggests a milder spring may follow. The signal is weak; combine it with the long-range forecast.
- Watch acorn drop near Michaelmas. Heavy acorn drop in late September often correlates with heavy nut and seed years across the northern hardwood forests, which can in turn correlate with a hard winter (the trees may be provisioning ahead). The signal is folklore-grade but real.
- Plan harvest by the lore + forecast combo. The saint-day sayings work as memorable date markers for harvest planning, even when the specific weather forecast turns out differently.
For more month-by-month folklore, see our April weather lore and November weather lore archives. For the broader animal-based weather tradition, see animal weather folklore. For an authoritative cross-reference on weather folklore traditions, the Old Farmer’s Almanac weather folklore reference covers many of the same sayings with regional variations.
Frequently Asked Questions
Is September weather lore actually accurate?
The pattern-based sayings (warm September correlating with mild March, dry-September-after-wet-May, six-week first-snow rule) have weak but measurable climate-science support. The saint-day sayings are folklore with no rigorous backing. Use the lore as a layered local signal, not a forecast.
When does winter usually arrive after September?
In the temperate U.S., the rule of thumb from old-time lore is that the first snowfall arrives roughly six weeks after the last September thunderstorm. For most of the Upper Midwest and Northeast, that puts first snow in early to mid-November.
What is Michaelmas?
September 29, the feast of St. Michael the Archangel. In medieval European calendars, Michaelmas marked the traditional end of the summer harvest and the start of autumn. The folklore phrase “on Michaelmas Day, the heat leaves us” reflects the seasonal transition that often happens around that date.
What does “thunder in September” predict?
The traditional saying says thunder in September indicates a good crop of grains and fruits the next year. The basis is real: late-season rain from September thunderstorms benefits grain ripening and fruit set for the following spring.
Does the September weather predict the coming March?
Weakly. A warm dry September often correlates with a similar atmospheric setup six months later, producing a warm dry March in the same region. The correlation is too loose to function as a forecast on its own but works as one input alongside the long-range outlook.
What does heavy acorn drop in September mean?
Folklore says many acorns at Michaelmas means a snowy Christmas. The basis is that heavy nut years often correlate with stress-response provisioning by oaks ahead of harsh winters. The signal is folklore-grade but consistent enough to be worth noting.
Why are there so many September sayings tied to specific dates?
Saint days served as memorable anchor points in pre-literate European farm calendars. “Michaelmas” was easier to remember than “September 29.” The sayings double as date-markers and forecasts, which is why so many have survived in the agricultural folklore record.
This article was published by the Staff at FarmersAlmanac.com. Any questions? Contact us at questions@farmersalmananac.com.
- Farmers' Almanac Staff
- Farmers' Almanac Staff
- Farmers' Almanac Staff
- Farmers' Almanac Staff
Mostly wet and cool in the mountains of North Carolina at about 3600 feet elevation .
It has been extremely wet for the last 4 weeks. Ready for some dry weather.
Bone dry till 09/25 , then 2 inches of rain . Yeah! Grass growing again . Hold off feeding hay for awhile. Fewer black walnuts this year . Noticed woolly worms more black so far.
It has been very hot and dry in South Georgia. Most of my lawn is a nice crunchy brown. I doubt I will have to mow my lawn anymore this year and that’s not the normal for this area.
Hi Gary, Thanks for sharing what you are experiencing in South Georgia. We hope you get just enough rain. It’s amazing how one good shower can bring the green back. Please stay in touch.
September has been pleasant, dry, and sunny up until this last week when t’s been humid and rainy.
Ah, ok, keep an eye on the next few days and make a note here or in your Almanac. Then let’s take another look in May. It’s more fun watching the weather when you do it together! Best wishes from all of us at FA.
After I read each folklore message, I got thinking to myself, don’t tell me ppl actually believe these lores even in the 21st century?
Hi Terri! While we don’t use folklore to make our famous long range forecasts, we do get a kick out of them. We hope you join us and follow along. Let’s discover which ones ring true in this century together. You may be surprised!