This report describes the typical weather at the McAllen-Miller International Airport (McAllen, Texas, United States) weather station over the course of an average year. It is based on the historical records from 1974 to 2012. Earlier records are either unavailable or unreliable.
McAllen, Texas has a hot semi-arid steppe climate. The area within 25 mi of this station is covered by grasslands (96%).
Over the course of a year, the temperature typically varies from 50°F to 97°F and is rarely below 38°F or above 101°F.
The warm season lasts from May 23 to September 20 with an average daily high temperature above 92°F. The hottest day of the year is August 7, with an average high of 97°F and low of 77°F.
The cold season lasts from December 1 to February 16 with an average daily high temperature below 75°F. The coldest day of the year is January 4, with an average low of 50°F and high of 69°F.
The length of the day varies significantly over the course of the year. The shortest day is December 21 with 10:30 hours of daylight; the longest day is June 20 with 13:47 hours of daylight.
The earliest sunrise is at 6:40am on June 6 and the latest sunset is at 8:30pm on June 27. The latest sunrise is at 7:46am on March 11 and the earliest sunset is at 5:40pm on November 28.
Daylight saving time (DST) is observed in this location during 2012, starting in the spring on March 11 and ending in the fall on November 4.
The median cloud cover ranges from 26% (mostly clear) to 82% (mostly cloudy). The sky is cloudiest on January 12 and clearest on August 5. The clearer part of the year begins around May 25. The cloudier part of the year begins around November 19.
On August 5, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 77% of the time, and overcast or mostly cloudy 21% of the time.
On January 12, the cloudiest day of the year, the sky is overcast, mostly cloudy, or partly cloudy 66% of the time, and clear or mostly clear 33% of the time.
The probability that precipitation will be observed at this location varies throughout the year. Precipitation is most likely around January 12, occurring in 33% of days. Precipitation is least likely around July 13, occurring in 19% of days.
Over the entire year, the most common forms of precipitation are light rain, thunderstorms, drizzle, and moderate rain.
Light rain is the most severe precipitation observed during 39% of those days with precipitation. It is most likely around January 8, when it is observed during 17% of all days.
Thunderstorms are the most severe precipitation observed during 25% of those days with precipitation. They are most likely around August 23, when it is observed during 12% of all days.
Drizzle is the most severe precipitation observed during 16% of those days with precipitation. It is most likely around January 13, when it is observed during 11% of all days.
Moderate rain is the most severe precipitation observed during 13% of those days with precipitation. It is most likely around September 22, when it is observed during 5% of all days.
During the warm season, which lasts from May 23 to September 20, there is a 22% average chance that precipitation will be observed at some point during a given day. When precipitation does occur it is most often in the form of thunderstorms (48% of days with precipitation have at worst thunderstorms), light rain (26%), moderate rain (14%), and heavy rain (11%).
During the cold season, which lasts from December 1 to February 16, there is a 30% average chance that precipitation will be observed at some point during a given day. When precipitation does occur it is most often in the form of light rain (50% of days with precipitation have at worst light rain), drizzle (31%), and moderate rain (12%).
Either snow is exceptionally unlikely to fall at any time during the year at this location or this station does not reliably report precipitation types.
The relative humidity typically ranges from 39% (comfortable) to 96% (very humid) over the course of the year, rarely dropping below 20% (dry) and reaching as high as 100% (very humid).
The air is driest around July 29, at which time the relative humidity drops below 43% (comfortable) three days out of four; it is most humid around September 11, exceeding 93% (very humid) three days out of four.
Dew point is often a better measure of how comfortable a person will find the weather than relative humidity because it more directly relates to whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid.
Over the course of a year, the dew point typically varies from 41°F (dry) to 76°F (very muggy) and is rarely below 24°F (dry) or above 78°F (oppressive).
There are two periods in the year that are most comfortable: The first is between January 1 and March 31 and the second is between November 6 and December 31. The air feels neither too dry nor too muggy during these periods.
Over the course of the year typical wind speeds vary from 2 mph to 20 mph (light air to fresh breeze), rarely exceeding 26 mph (strong breeze).
The highest average wind speed of 12 mph (moderate breeze) occurs around April 27, at which time the average daily maximum wind speed is 19 mph (fresh breeze).
The lowest average wind speed of 9 mph (gentle breeze) occurs around October 3, at which time the average daily maximum wind speed is 15 mph (moderate breeze).