St. Louis experiences the official advent of summer in
June. Temperatures continue their upward incline, creating warm, typically summery conditions. Average daytime temperatures climb to a pleasant 66.8°F, perfect for enjoying an outdoor picnic or a leisurely day boating on the Mississippi. The sunny days of June yield high UV indexes, encouraging residents to take necessary sun precautions. Intermittent spells of rainfall serve as a refreshing break from the summer heat.
Temperature
As
May transitions into June in St. Louis, a subtle temperature shift is observed, with average highs adjusting from a moderately hot 76.3°F to a still warm 85.1°F. The average low-temperature, in June, in St. Louis, is a refreshing 66.7°F.
Heat index
In June, the average heat index is appraised at a tropical 91.4°F. Ensure extra safety measures, heat exhaustion and heat cramps are likely. Continuous activity might result in heatstroke.
Heat index specifics point out values are for conditions of shade and a slight breeze. Direct exposure to sunlight could raise the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'felt air temperature', is a metric representing the sensation of warmth when air temperature and moisture come together. Additional elements including metabolic differences, the level of physical activity, and attire have a role in shaping the individual's temperature perception. Being aware that direct sunlight can impact the felt heat might mean an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly critical for babies and toddlers. Youngsters frequently overlook the need for breaks and fluid intake. Thirst is an advanced sign of dehydration - thereby highlighting the importance of keeping hydrated, particularly during long physical activities.
Humidity
In St. Louis, the average relative humidity in June is 67.1%.
Rainfall
In June, in St. Louis, the rain falls for 10 days. Throughout June, 4.29" of precipitation is accumulated. In St. Louis,
Missouri, during the entire year, the rain falls for 112.6 days and collects up to 40.94" of precipitation.
Snowfall
In St. Louis, Missouri, snow does not fall in May through
October.
Daylight
The month with the longest days in St. Louis, Missouri, is June, with an average of 14h and 48min of daylight.
On the first day of the month, sunrise is at 5:37 am and sunset at 8:19 pm. On the last day of June, in St. Louis, sunrise is at 5:39 am and sunset at 8:29 pm CDT.
Sunshine
In June, the average sunshine in St. Louis, Missouri, is 9.7h.
UV index
June through
August, with an average maximum UV index of 9, are months with the highest UV index in St. Louis. A UV Index reading of 8 to 10 represents a very high health vulnerability from exposure to the Sun's UV rays for the average person.
Note: The maximum UV index, 9 during June, leads to the following recommendations:
Remember to safeguard yourself. Rapid damage can occur to skin and eyes without protection. Stay in the shade and limit direct Sun exposure from 10 a.m. to 4 p.m., a time when UV radiation is particularly strong. Remember, however, that shade structures may not provide complete protection. Experience reduced UV exposure by about half when donning a wide-brim hat. Even under cloud cover, use sunscreen with at least an SPF 30 generously and reapply frequently post every swim or outdoor exercise.