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South Africa · Multi-region weather view

Stellenbosch

Cape vineyards spanning Simonsberg, Bottelary, central Stellenbosch and the Helderberg slopes.

Dry summers meet Atlantic and False Bay influence across a varied landscape. Heat, wind, water stress and late-season rain differ between inland hills and the cooler Helderberg-facing sites.

Climate comparisons use the 1991–2020 combined regional record · updated through Sep 13, 2026.

Current conditions

Observations through Sep 21, 2026 · 03:00 UTC

Temperature15.6°C
Dew Point14.6°C
Relative Humidity94%
24h Rainfall0.0 mmmodeled IFS total through Sep 20

Vintage explorer

Compare this vintage · View 2010 across regions →

Slightly warmer and moderately drier than normal.

Mean temperature18.7°C
Temperature anomaly+0.3°Cvs 1991-2020
Growing degree days2094base 10°C
Hot days0≥ 35°C

What stood out in 2010

No single weather pattern stands out in the regional record.

Close to the usual range · Low confidence

Temperature, rainfall, heat, and frost all stayed within the site's published thresholds.

No single weather pattern stands out in the regional record.

How unusual was 2010?

The ranking compares vintages that meet the data-coverage threshold and use the same source, regional rules, and 1991-2020 baseline.

Growing-season temperature

9th warmest of 35 vintages Warmer than 26 of 34 other vintages 18.7°C

Growing-season rainfall

10th driest of 35 vintages Drier than 25 of 34 other vintages 271.8 mm

Heat accumulation

10th highest of 35 vintages Higher than 25 of 34 other vintages 2095 GDD

Hot days

7th most of 35 vintages More than 0 of 34 other vintages 0 days

2010 month by month

Compared with 1991–2020

Follow heat accumulation, rainfall, frost exposure, and the region’s growing and harvest windows in calendar order.

Frost watch Growing season Harvest window
  1. 1–30
    Frost watchGrowing season

    Heat accumulation

    2010 113 GDD
    Typical 108 GDD

    Rainfall

    2010 32.9 mm
    Typical 72.7 mm
    2010 freezing days
    0
    Typical
    0.0

    Drier than the typical month.

  2. 1–31
    Frost watchGrowing season

    Heat accumulation

    2010 158 GDD
    Typical 180 GDD

    Rainfall

    2010 67.8 mm
    Typical 50.2 mm
    2010 freezing days
    0
    Typical
    0.0

    Wetter than the typical month.

  3. 1–30
    Frost watchGrowing season

    Heat accumulation

    2010 211 GDD
    Typical 224 GDD

    Rainfall

    2010 54.3 mm
    Typical 46.6 mm
    2010 freezing days
    0
    Typical
    0.0

    Close to the typical monthly pattern.

  4. 1–31
    Growing season

    Heat accumulation

    2010 318 GDD
    Typical 303 GDD

    Rainfall

    2010 17.2 mm
    Typical 28.5 mm

    Drier than the typical month.

  5. 1–31
    Growing seasonHarvest window

    Heat accumulation

    2010 371 GDD
    Typical 347 GDD

    Rainfall

    2010 13.3 mm
    Typical 25.1 mm

    Drier than the typical month.

  6. 1–28
    Growing seasonHarvest window

    Heat accumulation

    2010 360 GDD
    Typical 324 GDD

    Rainfall

    2010 21.4 mm
    Typical 20.8 mm

    Close to the typical monthly pattern.

  7. 1–31
    Growing seasonHarvest window

    Heat accumulation

    2010 346 GDD
    Typical 314 GDD

    Rainfall

    2010 23.6 mm
    Typical 26.8 mm

    Close to the typical monthly pattern.

  8. 1–30
    Growing seasonHarvest window

    Heat accumulation

    2010 217 GDD
    Typical 224 GDD

    Rainfall

    2010 41.5 mm
    Typical 58.7 mm

    Close to the typical monthly pattern.

View milestone calendar data as a table
Month2010 GDDTypical GDD2010 rainfallTypical rainfall2010 freezing daysTypical freezing days
September 2010 113 GDD 108 GDD 32.9 mm 72.7 mm 00.0
October 2010 158 GDD 180 GDD 67.8 mm 50.2 mm 00.0
November 2010 211 GDD 224 GDD 54.3 mm 46.6 mm 00.0
December 2010 318 GDD 303 GDD 17.2 mm 28.5 mm Outside frost windowOutside frost window
January 2011 371 GDD 347 GDD 13.3 mm 25.1 mm Outside frost windowOutside frost window
February 2011 360 GDD 324 GDD 21.4 mm 20.8 mm Outside frost windowOutside frost window
March 2011 346 GDD 314 GDD 23.6 mm 26.8 mm Outside frost windowOutside frost window
April 2011 217 GDD 224 GDD 41.5 mm 58.7 mm Outside frost windowOutside frost window
Calendar data and method

Monthly values are weighted across every configured regional sample using stored Google ARCO ERA5 daily reanalysis. “Typical” is the mean monthly total across 30 baseline seasons. GDD is counted only inside the configured growing window; freezing days are counted only inside the frost-watch window; rainfall covers every displayed calendar day.

Selected-vintage coverage is 100%. Source rows were last retrieved Sep 13, 2026.

Replay the 2010 growing season

242 daily regional observations

Move through the season to follow temperature, rainfall, accumulated heat, and recorded weather events day by day.

Replay data and method

Daily values are weighted across every configured regional sample using stored Google ARCO ERA5 reanalysis. Coverage is 100%. Source rows were last retrieved Sep 12, 2026.

The daily weather replay is complete, but the separate weather-event scan is not currently available for this vintage.

Closest weather matches

These years had the most similar growing-season and harvest weather.

  1. Closest match

    2023

    Most alike in Hot-day count and Growing-season mean temperature.

    Hot-day count
    the same: 0 days
    Growing-season mean temperature
    cooler: 0.0°C

    Largest difference: Harvest precipitation — more rain

    View 2023 →

  2. Second closest

    2019

    Most alike in Hot-day count and Growing-season mean temperature.

    Hot-day count
    the same: 0 days
    Growing-season mean temperature
    warmer: 0.0°C

    Largest difference: Harvest precipitation — more rain

    View 2019 →

  3. Third closest

    2024

    Most alike in Hot-day count and Harvest precipitation.

    Hot-day count
    the same: 0 days
    Harvest precipitation
    more rain: 9.0 mm

    Largest difference: Growing-season precipitation — less rain

    View 2024 →
How similar years are calculated

Method analog-v1-2026-07 standardizes six weather measures across 34 complete ARCO ERA5 comparison years, then measures the distance between them. The calculation runs when the page is requested.

Measures used: Growing-season mean temperature (20%); Growing degree days (15%); Hot-day count (15%); Growing-season precipitation (20%); Harvest precipitation (20%). Measures omitted because they did not vary: Spring frost exposure.

Calculated distances: 2023 0.307; 2019 0.420; 2024 0.463.

Growing-season temperature anomalyCompared with 1991-2020
Temperature anomaly by vintage, 1991 to 2026 A line above zero indicates a warmer growing season than the 1991–2020 baseline. Select a point to inspect that vintage. +2.6°C −2.6°C 1991 2000 2010 2020 2026
Growing-season rainfall anomaly
Rainfall anomaly by vintage, 1991 to 2026 Bars show millimeters above or below the 1991–2020 growing-season baseline. Select a bar to inspect that vintage. +320 mm −320 mm 1991 2000 2010 2020 2026
View historical chart data as a table
YearTemperature anomalyRainfall anomalyHot days
1991-0.4°C+92 mm0
1992-0.6°C+168 mm0
1993+0.5°C-132 mm0
1994-0.2°C-65 mm0
1995-0.5°C+22 mm0
1996-1.7°C+167 mm0
1997-0.1°C-68 mm0
1998-0.0°C-46 mm0
1999+0.5°C-76 mm1
2000-0.1°C-26 mm1
2001+0.1°C+125 mm0
2002+0.2°C-37 mm0
2003-0.3°C+55 mm0
2004+0.6°C+90 mm0
2005-0.1°C-117 mm0
2006+0.0°C-1 mm0
2007+0.0°C-4 mm0
2008-0.1°C+38 mm0
2009-0.1°C+38 mm2
2010+0.3°C-58 mm0
2011-0.1°C+36 mm0
2012+0.1°C+38 mm0
2013+0.1°C+135 mm0
2014+0.4°C-128 mm1
2015+0.6°C-13 mm1
2016+0.5°C-131 mm0
2017+0.0°C-8 mm0
2018+0.1°C-32 mm0
2019+0.4°C-47 mm0
2020-0.2°C-17 mm0
2021-0.1°C-46 mm0
2022-0.2°C+2 mm0
2023+0.3°C-43 mm0
2024+0.2°C-126 mm0
2025+0.5°C-60 mm1
2026-2.3°C-311 mm0

winter

12.3°C

+0.2°C vs baseline

242 mm rain · -128 mm

spring

15.3°C

-0.3°C vs baseline

154 mm rain · -15 mm

summer

21.7°C

+0.9°C vs baseline

51 mm rain · -23 mm

harvest

21.6°C

+1.1°C vs baseline

62 mm rain · -35 mm

Weather events

1991–present

Climate change

Measured regional trends are shown separately from model projections. The observed record ends at the latest complete growing season shared by every published region.

Compare regions

Observed record

Historical trends, 1991–2025

Growing degree days changed +39.4 GDD per decade. The 95% interval is +8.7 to +70.1 GDD per decade, based on 35 eligible vintages.

How it is measured: Across the September 1–April 30 growing season, each day's mean temperature above 10°C adds to the total; cooler days add zero.

Growing degree days · annual change from the 1991–2020 average1991–2025

Scroll horizontally to inspect the full timeline.

View annual growing degree days data
VintageGrowing degree daysChange from 1991–2020
19911945 GDD-78 GDD
19921873 GDD-150 GDD
19932143 GDD+120 GDD
19941975 GDD-48 GDD
19951911 GDD-112 GDD
19961616 GDD-408 GDD
19972008 GDD-15 GDD
19982014 GDD-9 GDD
19992154 GDD+130 GDD
20001995 GDD-28 GDD
20012045 GDD+22 GDD
20022070 GDD+47 GDD
20031959 GDD-64 GDD
20042176 GDD+153 GDD
20051989 GDD-34 GDD
20062021 GDD-2 GDD
20072031 GDD+8 GDD
20082003 GDD-20 GDD
20092004 GDD-19 GDD
20102095 GDD+72 GDD
20111996 GDD-27 GDD
20122034 GDD+11 GDD
20132047 GDD+24 GDD
20142111 GDD+88 GDD
20152171 GDD+147 GDD
20162136 GDD+113 GDD
20172022 GDD-2 GDD
20182058 GDD+35 GDD
20192117 GDD+94 GDD
20201978 GDD-45 GDD
20212001 GDD-22 GDD
20221968 GDD-56 GDD
20232106 GDD+82 GDD
20242063 GDD+39 GDD
20252149 GDD+125 GDD
Growing-season mean temperature
+0.16 °C per decade 95% interval +0.04 to +0.29
Growing degree days
+39.39 GDD per decade 95% interval +8.70 to +70.08
Growing-season precipitation
-24.85 mm per decade 95% interval -42.21 to -7.50
Hot days
+0.04 days per decade 95% interval -0.08 to +0.17
Spring frost days
No variation recorded
Longest dry spell
-0.97 days per decade 95% interval -3.33 to +1.38

Last Updated September 13, 2026

Model ensemble

Projected climate through 2075

Temperature changes are relative to each model’s 1991–2020 baseline. The table combines all three pathways, weighted 70% to SSP2-4.5 and 15% each to SSP1-2.6 and SSP3-7.0.

Scroll horizontally to compare all columns.

PeriodWeighted medianWeighted central 80%Models per pathway
2021-2040+0.5°C+0.3 to +0.7°C25
2041-2060+1.0°C+0.7 to +1.3°C25
2061-2075+1.3°C+0.9 to +1.7°C25
How pathways are combined

For each period and percentile, Weather & Vines takes 70% of the SSP2-4.5 value, 15% of the SSP1-2.6 value, and 15% of the SSP3-7.0 value. Each pathway contains the same 25 models. The weights are an editorial view of the current trajectory, not scenario probabilities.

Last Updated June 29, 2025

Compare projection measures across regions

Typical year · 1991–2020

When to visit

This calendar describes typical regional weather under the selected climate baseline. It is not a forecast for a future trip, and it does not account for crowds, lodging, events, or vineyard access.

Deterministic IFS forecast

Next ten days

Detailed forecast outlook

ECMWF IFS 0.25° via Herbie · model run Sep 20, 2026 at 00:00 UTC · retrieved Sep 21, 2026 at 03:23 UTC

Scroll horizontally to see all forecast dates.

DateMonTueWedThuFriSatSunMonTueWed
High 29°C 31°C 27°C 21°C 18°C 18°C 19°C 21°C 23°C 14°C
Low 15°C 17°C 17°C 16°C 14°C 14°C 13°C 15°C 14°C 14°C
Rain 0.1 mm 7.9 mm 0.0 mm 0.0 mm 20.8 mm 7.5 mm 0.1 mm 1.8 mm 0.0 mm 0.0 mm

Across the typical year: Late February has the warmest median afternoon high (25.8°C); Early August has the coolest (15.1°C). Wet days are most frequent in Early June (40%) and least frequent in Late February (11%). Ties are resolved by calendar order.

Typical afternoon highs and overnight lowsMedians and middle 50% of daily readings

Afternoon highOvernight lowMiddle 50%

Scroll horizontally to inspect all 24 half-month periods.

Typical afternoon highs and overnight lows for Stellenbosch Median daily maximum and minimum temperatures for 24 early and late-month periods under the 1991–2020 baseline. Neutral bands show the 25th to 75th percentile. 5°C10°C15°C20°C25°C30°C JanFebMarAprMayJunJulAugSepOctNovDec
How often a day is wetShare of days with at least 1 mm of rain

Scroll horizontally to inspect all 24 half-month periods.

Wet-day frequency through the typical year for Stellenbosch The fraction of days receiving at least one millimeter of rain in each early and late-month period under the 1991–2020 baseline. 0%25%50%75%100% JanFebMarAprMayJunJulAugSepOctNovDec
View all 24 periods as a table

Scroll horizontally to view all columns.

Stellenbosch typical weather by half-month, 1991–2020
PeriodAfternoon high, median (middle 50%)Overnight low, median (middle 50%)Wet-day frequencyPeriod rain, median (middle 50%)
Jan 1–1525.2°C (23.1–27.8°C)16.4°C (15.3–17.6°C)14%7.9 mm (4.4–20.2 mm)
Jan 16–3125.6°C (23.7–28.2°C)16.8°C (15.6–18.0°C)12%7.2 mm (3.3–15.4 mm)
Feb 1–1525.7°C (23.7–28.5°C)17.1°C (15.9–18.2°C)16%10.6 mm (4.9–16.4 mm)
Feb 16–2925.8°C (23.6–28.4°C)16.9°C (15.8–18.0°C)11%5.4 mm (2.4–10.3 mm)
Mar 1–1525.2°C (22.8–27.8°C)16.3°C (15.1–17.5°C)12%8.0 mm (2.8–14.2 mm)
Mar 16–3123.7°C (21.8–26.0°C)15.3°C (14.2–16.3°C)16%8.4 mm (5.5–18.0 mm)
Apr 1–1522.8°C (20.2–25.5°C)14.0°C (12.5–15.3°C)20%15.2 mm (8.2–33.6 mm)
Apr 16–3020.4°C (18.1–23.2°C)12.3°C (10.8–13.7°C)23%34.9 mm (10.8–50.8 mm)
May 1–1519.4°C (17.3–21.9°C)11.5°C (10.1–12.7°C)27%25.3 mm (9.9–35.2 mm)
May 16–3117.5°C (15.7–20.0°C)10.5°C (9.0–11.9°C)36%55.0 mm (37.0–77.9 mm)
Jun 1–1515.9°C (14.4–18.0°C)9.1°C (7.4–10.8°C)40%66.8 mm (45.6–101.8 mm)
Jun 16–3015.4°C (14.0–17.8°C)8.3°C (6.8–9.7°C)37%54.4 mm (27.1–74.3 mm)
Jul 1–1515.4°C (13.6–18.2°C)8.0°C (6.3–9.5°C)36%56.7 mm (21.2–83.0 mm)
Jul 16–3115.2°C (13.4–17.5°C)7.7°C (6.2–9.3°C)34%52.6 mm (29.3–95.8 mm)
Aug 1–1515.1°C (13.6–17.4°C)7.9°C (6.4–9.4°C)38%47.4 mm (32.8–74.6 mm)
Aug 16–3115.7°C (13.8–18.3°C)8.3°C (6.9–10.0°C)37%52.6 mm (26.7–64.3 mm)
Sep 1–1516.6°C (14.8–19.1°C)9.4°C (8.0–10.6°C)32%28.5 mm (15.3–50.1 mm)
Sep 16–3017.3°C (15.3–20.1°C)9.8°C (8.3–11.4°C)32%28.6 mm (22.7–49.9 mm)
Oct 1–1519.1°C (16.6–21.7°C)11.0°C (9.6–12.4°C)24%16.2 mm (9.8–26.3 mm)
Oct 16–3120.1°C (17.7–23.2°C)12.2°C (10.7–13.6°C)25%20.9 mm (10.4–44.6 mm)
Nov 1–1521.2°C (18.7–23.9°C)13.1°C (11.7–14.2°C)25%17.0 mm (9.4–39.2 mm)
Nov 16–3022.0°C (19.8–24.7°C)13.4°C (12.3–14.7°C)20%15.1 mm (10.3–25.9 mm)
Dec 1–1523.8°C (21.6–26.3°C)15.0°C (13.8–16.3°C)17%9.2 mm (4.5–15.4 mm)
Dec 16–3124.1°C (22.0–26.5°C)15.7°C (14.4–16.9°C)18%12.4 mm (7.7–18.6 mm)

Each year contributes to temperature or rain separately when at least 90% of that period’s days are present. A value is shown only when at least 80% of the baseline years qualify. February 29 is included in late February.

Historical climatology Last Updated September 13, 2026

Season to date

Growing season heat and rainfall

Sep 1–Sep 20, 2026

Compare this season across regions →

Growing degree days78.2base 10°C
Growing-season rainfall18.9 mmweighted regional total
Cumulative growing degree daysBase 10°C

2026 season1991–2020 average

Growing degree days accumulated during the 2026 growing season The solid line accumulates daily mean temperature above 10 degrees Celsius from the configured growing-season start. The dashed line shows the 1991–2020 daily climatological average. 78 GDD 0 Sep ’26
Cumulative growing-season rainfallRegional weighted mean

2026 season1991–2020 average

Rainfall accumulated during the 2026 growing season The solid line accumulates daily rainfall in millimeters from the configured growing-season start. The dashed line shows the 1991–2020 daily climatological average. 32 mm 0 Sep ’26
View growing-season accumulation data
DateSeason GDD1991–2020 average GDDSeason rainfall1991–2020 average rainfall
2026-09-011.93.00.0 mm2.4 mm
2026-09-024.96.10.0 mm5.7 mm
2026-09-037.09.02.1 mm8.0 mm
2026-09-0412.012.12.3 mm9.2 mm
2026-09-0517.215.12.3 mm13.6 mm
2026-09-0625.318.52.3 mm14.4 mm
2026-09-0734.422.02.3 mm17.6 mm
2026-09-0843.925.32.3 mm21.6 mm
2026-09-0951.628.12.3 mm25.5 mm
2026-09-1057.030.92.3 mm28.1 mm
2026-09-1164.134.22.3 mm29.2 mm
2026-09-1270.037.912.0 mm30.8 mm
2026-09-1378.242.018.9 mm32.3 mm

Forecast outlook

ECMWF IFS 0.25° via Herbie · run Sep 20, 2026 at 00:00 UTC

10-day totals compared with the 1991–2020 combined regional record

GDD accumulation
78 GDDvs 39 GDD average
Total rainfall
38.3 mmvs 22.5 mm average

A notable amount of rain is forecast during the period. The 10-day total meets the 30 mm forecast threshold, with rain forecast Sep 21–23 and Sep 25–28.

Mon9/21 29°Cavg 18°C 15°Cavg 10°C +12 GDD 0.1 mm
Tue9/22 31°Cavg 19°C 17°Cavg 10°C +14 GDD 7.9 mm
Wed9/23 27°Cavg 18°C 17°Cavg 10°C +10 GDD 0.0 mm
Thu9/24 21°Cavg 17°C 16°Cavg 10°C +8 GDD 0.0 mm
Fri9/25 18°Cavg 18°C 14°Cavg 10°C +6 GDD 20.8 mm
Sat9/26 18°Cavg 17°C 14°Cavg 10°C +5 GDD 7.5 mm
Sun9/27 19°Cavg 17°C 13°Cavg 10°C +6 GDD 0.1 mm
Mon9/28 21°Cavg 18°C 15°Cavg 9°C +7 GDD 1.8 mm
Tue9/29 23°Cavg 19°C 14°Cavg 10°C +7 GDD 0.0 mm
Wed9/30 14°Cavg 19°C 14°Cavg 10°C +4 GDD 0.0 mm

Data and methods

Show data sources and model assumptions

Current model conditions and the 10-day outlook use the 00 UTC deterministic ECMWF IFS 0.25° public forecast retrieved directly with Herbie. Historical temperature and rain combine qualifying GHCN-D stations with ERA5 by geographic area; a missing station day uses the nearest ERA5 value for that station's area. Climate comparisons use 1991–2020.

Forecast comparisons use the 1991–2020 combined regional daily record. Daily high and low averages use the matching date; rainfall and GDD sum the same calendar dates as the forecast period.

This service is based on data and products of the European Centre for Medium-Range Weather Forecasts (ECMWF). Weather & Vines subsets, converts, and regionally weights the forecast fields. ECMWF data are published under CC BY 4.0. ECMWF accepts no liability for errors, omissions, availability, loss, or damage arising from their use.

Climate projections use NASA NEX-GDDP-CMIP6 v2.0, accessed September 20, 2026, with 25 models. Weather & Vines subsets and aggregates the source fields. Source files and derived projection data are under CC BY-SA 4.0; the full roster and limitations are listed in the climate atlas methods.

The Stellenbosch model uses a September 1–April 30 growing season, base 10°C GDD, and an operational hot-day marker of 35°C.