May weather forecast and climate
Houston, TX

A beautiful park in Root square overlooking the central business district of Houston, Texas, USA
A beautiful park in Root square overlooking the central business district of Houston, Texas, USA
The last month of the spring, May, is another warm month in Houston, Texas, with average temperature ranging between min 70°F (21.1°C) and max 85.8°F (29.9°C).

Temperature

In Houston, the average high-temperature slightly increases, from 78.8°F (26°C) in April, to a still moderately hot 85.8°F (29.9°C). In May, in Houston, Texas, the average low-temperature is 70°F (21.1°C).

Heat index

In May, the average heat index is appraised at a very hot 96.4°F (35.8°C). Take special precautions - heat exhaustion and heat cramps are expected. Heatstroke may occur with lengthy activity.
Note that heat index values are valued for light wind and location in the shade. With the exposure to direct sunlight, the heat index may be increased by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like', 'real feel', 'felt air temperature', or 'apparent temperature', is calculated by taking the relative humidity value for a specific location and factoring it into the air temperature reading. This effect is individual, with diverse people perceiving weather differently for numerous reasons (pregnancy, wind, clothing), and activity. Be aware that direct exposure to sunlight increases heat impact, and may raise the heat index additionally, by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly important for children. Young children are generally more endangered than adults, as they usually less sweat. And also, due to larger skin surface relative to their small bodies and higher heat production as a result of their activity.
The human body normally cools itself by perspiration. Excessive warmth is eliminated from the body by evaporation of sweat. With a lot of moisture in the air, the evaporation process is not as effective, and the body does not cool down as efficiently, creating a perception of overheating. If the body can not disperse the excessive heat and body temperature reaches conditions of hyperthermia, above 99.5°F (37.5°C) to 100.9°F (38.3°C), thermal conditions are potentially life-threatening.

Humidity

The average relative humidity in Houston is 74%.

Rainfall

In Houston, during 14.8 rainfall days, 4.45" (113mm) of precipitation is typically accumulated. Throughout the year, in Houston, there are 180.5 rainfall days, and 35.35" (898mm) of precipitation is accumulated.

Snowfall

In Houston snow does not fall in February through November.

Daylight

In May, the average length of the day in Houston is 13.7h.

Sunshine

The average sunshine in Houston is 9.3h.

UV index

Months with the highest UV index in Houston are May through August, with an average maximum UV index of 7. A UV Index value of 6 to 7 symbolizes a high health vulnerability from the exposure to the Sun's UV radiation for the average person.
Note: The daily maximum UV index of 7 interpret into the following advice:
Take precautions against overexposure. Protection against sun damage is needed. Seek shade and minimize exposure to direct Sun in a period between 10 a.m. and 4 p.m. when UV radiation is most intense; keep in mind that shade structures like parasols or canopies do not provide perfect sun protection. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects.

What is the temperature in May in Houston?

The average high-temperature, in May, in Houston, Texas, is 85.8°F (29.9°C), while the average low-temperature is 70°F (21.1°C). In May, the average heat index (a.k.a. 'real feel', 'apparent temperature'), that combines relative humidity and air temperature, is estimated at 96.4°F (35.8°C).

What is the average humidity in May in Houston?

The average relative humidity in May in Houston is 74%.

How many days does it rain in May in Houston?

In Houston, in May, during 14.8 rainfall days, 4.45" (113mm) of precipitation is typically accumulated.

When it does not snow in Houston?

In Houston snow does not fall in February through November.

How many hours of daylight does Houston have in May?

In May, the average length of the day in Houston is 13.7h.

How many hours of sunshine does Houston have in May?

In May, the average sunshine in Houston, Texas, is 9.3h.

What is the month with the highest UV index in Houston?

May through August, with an average maximum UV index of 7, are months with the highest UV index in Houston, Texas.

What is the UV index reading in May in Houston?

The average daily maximum UV index in May in Houston is 7. A UV Index of 6 to 7 symbolizes a high health vulnerability from the exposure to the Sun's UV radiation.
Average temperature in May - Houston, TX
  • Average high temperature in May: 85.8°F

The warmest month (with the highest average high temperature) is August (94.3°F).
The month with the lowest average high temperature is January (61.3°F).

  • Average low temperature in May: 70°F

The month with the highest average low temperature is August (77.5°F).
The coldest month (with the lowest average low temperature) is January (46°F).

Average pressure in May - Houston, TX
  • Average pressure in May: 29.95"

The month with the highest atmospheric pressure is January (30.16").
The month with the lowest atmospheric pressure is June (29.93").

Average wind speed in May - Houston, TX
  • Average wind speed in May: 8mph

The windiest month (with the highest average wind speed) is April (8.6mph).
The calmest month (with the lowest average wind speed) is September (5.9mph).

Average humidity in May - Houston, TX
  • Average humidity in May: 74%

The month with the highest relative humidity is February (78%).
Months with the lowest relative humidity are August and October (70%).

Average rainfall in May - Houston, TX
  • Average rainfall in May: 4.45"

The wettest month (with the highest rainfall) is September (4.49").
The driest month (with the least rainfall) is February (1.77").

Average rainfall days in May - Houston, TX
  • Average rainfall days in May: 14.8 days

The month with the highest number of rainy days is September (19.5 days).
The month with the least rainy days is January (11.8 days).

Average snowfall in May - Houston, TX
  • Average snowfall in May: 0"

The month with the highest snowfall is December (0.08").
Months with the least snowfall are February, March, April, May, June, July, August, September, October and November (0").

Average snowfall days in May - Houston, TX
  • Average snowfall days in May: 0 days

Months with the highest number of snowfall days are January and December (0.1 days).
Months with the least snowfall days are February, March, April, May, June, July, August, September, October and November (0 days).

Average daylight in May / Average sunshine in May - Houston, TX
  • Average daylight in May: 13.7h

The month with the longest days is June (Average daylight: 14h).
The month with the shortest days is December (Average daylight: 10.3h).

  • Average sunshine in May: 9.3h

The month with the most sunshine is August (Average sunshine: 10.5h).
The month with the least sunshine is December (Average sunshine: 4.8h).

Average sunshine days in May - Houston, TX
  • Average sunshine days in May: 14.2 days

The month with the most sunshine days is January (16.3 days).
The month with the least sunshine days is September (7.9 days).

Average UV index in May - Houston, TX
  • Average UV index in May: 7

Months with the highest UV index are May, June, July and August (UV index 7).
The month with the lowest UV index is December (UV index 3).

Average cloud cover in May - Houston, TX
  • Average cloud cover in May: 39

The month with the most cloud cover is February (Cloud cover 51).
The month with the least cloud cover is August (Cloud cover 27).

Average visibility in May - Houston, TX
  • Average visibility in May: 6mi

Months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
Months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).