This report describes the typical weather at the Queen Beatrix International Airport (Oranjestad, Aruba) weather station over the course of an average December 31. It is based on the historical records from 1974 to 2012. Earlier records are either unavailable or unreliable.
Oranjestad has a hot desert climate. The area within 25 mi of this station is covered by oceans and seas (95%) and grasslands (2%).
The temperature typically varies from 77°F to 85°F and is rarely below 75°F or above 87°F.
The coolest hours of the day are from 11pm to 8am with the coldest at 7am, at which time the temperature is below 79°F three days out of four.
The warmest hours of the day are from 11am to 5pm with the hottest at 2pm, at which time the temperature is above 83°F three days out of four.
The day has gained half its heat by 10am and lost it again by 6pm.
On December 31 the Sun rises at 7:01am and sets at 6:25pm.
Solar noon is at 12:43pm.
For reference, on the longest day of the year the Sun rises at 6:15am and sets at 7:07pm, while on the shortest day of the year it rises at 6:56am and sets at 6:20pm.
Astronomical twilight begins and ends 75 minutes before sunrise and after sunset at 5:45am and 7:41pm, respectively.
Nautical twilight begins and ends 49 minutes before sunrise and after sunset at 6:11am and 7:15pm, respectively.
Civil twilight begins and ends 23 minutes before sunrise and after sunset at 6:38am and 6:48pm, respectively.
Solar twilight begins and ends 30 minutes after sunrise and before sunset at 7:31am and 5:54pm, respectively.
The median cloud cover ranges from 30% (mostly clear) to 45% (partly cloudy).
At 11pm, the clearest time of the day, the sky is clear, mostly clear, or partly cloudy 69% of the time, and overcast or mostly cloudy 5% of the time.
At noon, the cloudiest time of the day, the sky is overcast, mostly cloudy, or partly cloudy 45% of the time, and clear or mostly clear 38% of the time.
The sky is typically clearing in earnest by 6pm.
The clouds have typically started forming in earnest by 7am.
There is a 43% chance that precipitation will be observed at some point during the day.
When precipitation does occur it is most often in the form of moderate rain (85% of days with precipitation have at worst moderate rain) and slight rain (10%).
Precipitation is most likely around 10am and least likely around 1am.
Either snow is exceptionally unlikely to fall at this location on December 31 or this station does not reliably report precipitation types.
The relative humidity typically ranges from 70% (mildly humid) to 83% (humid), rarely dropping below 62% (mildly humid), or exceeding 90% (very humid).
The air is driest at 1pm, at which time the relative humidity is less than 74% (humid) three days out of four; it is most humid at 5am, exceeding 79% (humid) three days out of four.
The dew point ranges from 72°F to 73°F with an average of 73°F, which feels muggy no matter what the relative humidity is.
For reference, comfortable indoor conditions should have a relative humidity between 30% and 50% with a dew point of less than 65°F.
Sustained wind speeds typically vary from 12 mph to 20 mph (gentle breeze to fresh breeze) over the course of the day.
The peak sustained wind speed typically occurs around noon and is rarely outside the range 13 mph to 23 mph (moderate breeze to fresh breeze).
The wind is most calm around 6am, rarely exceeding 17 mph (moderate breeze).
The wind is most often out of the east (60% of the time). The wind is least often out of the south west (0% of the time), west (0% of the time), north west (0% of the time), north (0% of the time), south (0% of the time), and south east (2% of the time).