Weather in Sioux City

Stay informed about the latest weather conditions in Sioux City. In this section, you will find up-to-date data, forecasts, and useful weather charts to help plan your time.

The city of Sioux City, located in the United States, is characterized by a continental climate with distinct seasons. Winters here are cold, with average temperatures in January and February dropping below freezing, reaching -5.2°C and -4.0°C respectively. Summer, on the other hand, is warm and even hot: in July, the average temperature is 24.8°C, while in June and August it stays around 23.6°C - 23.7°C. Spring and autumn are transitional periods with moderate temperatures.

One of the distinctive features of the Sioux City climate is the relatively low level of precipitation throughout the year. Most months are characterized by a small amount of precipitation, typically between 1 and 3 mm. A slight increase is observed in May, when up to 4 mm of precipitation falls and the highest number of rainy days (about 15) is noted. Despite this, the city cannot be called rainy, which is worth considering when planning your trip.

The climate in Sioux City is characterized by significant seasonal temperature fluctuations. The annual temperature regime demonstrates a clear division into warm and cold seasons. The coldest months are January with an average temperature of -5.2°C (minimum around -9.4°C, maximum -0.9°C) and February, where the average temperature is -4.0°C (minimum -9.4°C, maximum 1.4°C). The hottest period is considered to be July, when the average temperature reaches 24.8°C, with daytime highs up to 30.0°C and nighttime lows around 19.7°C. It is slightly cooler in June and August, with average temperatures of 23.6°C and 23.7°C respectively.

The summer months in Sioux City, from June to August, bring warm and occasionally hot weather. Average daytime temperatures confidently stay above 28°C, and in July can reach 30°C. Nights also remain warm, with temperatures rarely dropping below 18-19°C. The difference between day and night temperatures in summer is approximately 10-11°C, indicating a noticeable but not drastic cooling of the air after sunset. The transitional seasons, spring and autumn, are distinguished by more moderate temperatures. For example, in April the average temperature is 9.8°C, and in October it is 12.1°C, while daily fluctuations can be more pronounced, especially in spring.

Winter in Sioux City, covering December, January, and February, is frosty. Monthly average temperatures are consistently below freezing, especially in January. Nighttime temperatures regularly drop to -9°C and lower, while daytime temperatures often remain slightly below or around the freezing point. Even in December, the "mildest" of the winter months, the average temperature is -1.5°C. Daily temperature fluctuations in winter are also noticeable, averaging 8-10°C, which means that even if the temperature rises slightly above freezing during the day, frost should be expected at night.

In Sioux City, a change in precipitation patterns is observed throughout the year, yet the total amount remains very low. Despite this, one can distinguish a slightly wetter period falling in late spring and summer, and a drier, cold period in winter. In winter, precipitation mainly falls as snow, whereas in the warm season, it is typically rain.

The highest, though still insignificant, amount of precipitation in Sioux City occurs in late spring and early summer. May and June are the months with the maximum rainfall level for this region, averaging 4 mm. May also stands out with the highest number of days with precipitation — about 15 days. In June, the number of rainy days is approximately 11. April (3 mm of precipitation, 10 days with precipitation) and August (3 mm of precipitation, 10 days with precipitation) are also characterized by a slightly higher amount of moisture compared to winter months, while remaining at a very low level. In these months, precipitation usually comes in the form of rain.

The winter months — January, February, and December — as well as November, are the driest. During this period, precipitation amounts to only about 1 mm per month, and the number of days with precipitation does not exceed 5 days. Given that average temperatures in January (-5.2°C), February (-4.0°C), and December (-1.5°C) drop below freezing, precipitation at this time of year falls predominantly as snow. In November, with an average temperature of +4.5°C, snowfall is also possible alongside rain. Other months, such as March, July, September, and October, are also characterized by very low precipitation levels (2 mm), with the number of days with precipitation varying from 7 to 8.

When planning a trip to Sioux City, it is important to consider the distinct change of seasons so that your wardrobe matches the weather conditions. Regardless of the time of year, comfortable walking shoes will be your faithful companion. The principle of layering clothing is the key to comfort, as it allows you to easily adapt to temperature changes throughout the day, especially during the transitional seasons.

In winter (December-February), Sioux City is quite cold: the average temperature drops below freezing (to -5°C), and the minimum can reach -9°C. You will need very warm clothes: a winter jacket or down coat, a hat, a scarf, gloves, and possibly thermal underwear. Despite the small amount of precipitation (about 1 mm), it can be snow, so waterproof shoes and outerwear will be very useful. November and March are also cool, so warm clothes remain relevant.

The summer months (June-August) are characterized by warm weather with an average temperature around 23-25°C, and daytime highs can reach 30°C. Pack light, breathable clothing: t-shirts, shorts, sundresses. Don't forget sunscreen, a hat, and sunglasses. Evenings can be cooler, so a light jacket or sweater will come in handy. In spring (April-May) and autumn (September-October), the weather is milder but changeable. May sees the highest number of rainy days (up to 15), so a compact umbrella or a light raincoat will be useful. During these periods, layered clothing is also relevant: from t-shirts to light jackets and sweaters.