Why is it so Hot in Hawaii?

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heat in hawaii

Why is it So Hot in Hawaii? Causes and How to Beat the Heat

Why is it So Hot in Hawaii?

The hot weather in Hawaii is caused by a combination of factors. One is the island’s proximity to the equator, where the sun’s rays are much stronger than in other parts of the world. Additionally, Hawaii has seen a consistent rise in temperatures since the 1950s, with an average increase of 0.3°F every decade. This is four times the rate of half a century ago. Strong El Niño years are also linked to hot days, intense rains, windless days, active hurricane seasons, and spikes in sea surface temperature, which can worsen the frequency and intensity of ENSO events. On top of this, Hawaii has seen periods of light or no tradewinds throughout the summer, further compounding the heat. All of these factors contribute to the abnormally hot weather seen in Hawaii this summer, with numerous heat records being broken or tied.

An orange sunset on the Big Island.

What are the causes of high temperatures in Hawaii?

1. Location

The temperature in a location in Hawaii is affected by a variety of factors. First, its close proximity to the equator ensures that the length of the day is constant throughout the year and that temperatures remain mild. Second, the trade winds, primarily from the east or northeast, also contribute to mild temperatures. Third, the mountainous terrain of the islands and their closeness to the ocean create microclimates which can cause significant differences in temperature and rainfall between close distances. Finally, the ocean itself serves as a moderating influence on temperatures, as it absorbs and releases heat. All of these factors combine to create the perfect climate for a year-round outdoor lifestyle in Hawaii.

2. Topography

The topography and temperatures in Hawaii are largely affected by the prevailing trade winds, exposure to windward or leeward sides of the islands, and elevation. Windward sides of the islands experience a moderate amount of rainfall from the trade wind showers and are subject to more uniform and mild temperatures. Leeward sides of the islands are drier and experience slightly higher temperatures during the day and slightly lower temperatures during the night due to the reduced amount of rainfall and lack of protection from the prevailing winds. The Kona coast of Hawaii is a unique case because it experiences higher amounts of rainfall in the summer months due to the well-developed land and sea breezes. In the interior lowlands on Oahu and Maui, local afternoon showers form due to the heating of the land during the day. Elevation is also a factor, with the highest rainfall levels located at 2,000-4,000 feet on the flanks of the large, high mountains. The driest areas are located on the upper slopes of the high mountains, on leeward coasts, and in the leeward locations in the interior of the islands.

3. Trade Winds

The trade winds in Hawaii bring a constant flow of fresh temperate air from the north-east and create a wind wake that extends 1,860 miles (3,000 km). This flow of air helps to naturally cool the islands and provide the cleanest air anywhere on the planet. Additionally, the trade winds cause a counter current in the ocean, bringing warm water from the Asian coast and further influencing the climate. This wind wake and counter current extend far into the western Pacific and contribute to the unique climate of the Hawaiian Islands, creating an average temperature of 78°F (25°C) year-round. The trade winds also provide a cool, refreshing breeze during warmer months, preventing temperatures from becoming too hot.

4. Climate

The climate characteristics of high temperatures in Hawaii are becoming increasingly extreme as greenhouse gases are emitted into the atmosphere. The ocean temperatures off of the islands are several degrees higher than normal, leading to less frequent tradewinds that usually provide relief from the hot and humid weather. The lack of land mass in Hawaii prevents an upwelling of cool water, making it difficult for the islands to cool down. This combination of effects has led to some of the most uncomfortable summer temperatures the islands have experienced, with record highs almost every day since April. Climate change is also causing other dangerous effects such as heat waves, drought, flooding, and sea level rise. It is essential that action is taken to reduce greenhouse gas emissions and combat the dangerous effects of climate change.

5. Heat Waves

Heat waves are periods of excessively hot weather caused by changes in atmospheric pressure, which trap hot air in a certain area. In Hawaii, heat waves occur because of its geographical location near the equator, where temperatures are naturally quite high. This is exacerbated by climate change, as higher greenhouse gas emissions trap more heat in the atmosphere, resulting in even hotter temperatures. Heat waves in Hawaii are further amplified by its lack of land mass, which prevents an upwelling of cool water like on the mainland, and the decreasing frequency of trade winds, which usually provide a cooling breeze to the islands. All of these factors combine to create a recipe for the hot, muggy weather that Hawaii has been experiencing over the past months.

6. Summer Thunderstorms

The cause of high temperatures in Hawaii during summer storms is due to its proximity to the equator and the steady influx of solar energy. This consistent amount of sunlight year-round creates a warm and humid climate, resulting in intense summer storms. These storms can be triggered by cold fronts that sweep across the islands, bringing with them locally heavy showers and gusty winds. In addition, upper low pressure areas in the atmosphere, Kona storms, and tropical storms can also contribute to high temperatures and intense storms in Hawaii during summer months.

7. Hurricanes

Hurricanes can have a significant impact on the temperature in Hawaii, but the effects vary depending on the type of storm. Hurricanes and tropical storms can cause temperatures to drop as they bring in winds and precipitation, while Kona storms and cold fronts can cause temperatures to increase as they bring in warmer air and increased pressure. Hurricanes and tropical storms can also cause high waves, which can bring cooler ocean temperatures to the islands. On the other hand, Kona storms and cold fronts can cause warmer temperatures as the air pressure increases and the air is warmed by the sun. In the most extreme cases, hurricanes can cause considerable damage and destruction, while Kona storms and cold fronts are usually less destructive. Overall, hurricanes are the most significant weather phenomenon to affect temperatures in Hawaii, followed by tropical storms, Kona storms, and cold fronts.

8. Low Pressure Systems

Low pressure systems in the upper atmosphere can cause severe weather in Hawaii, such as towering cumulus clouds, thunderstorms, and intense and widespread rain. These upper Lows or troughs are often mistaken for Kona storms, which are slowly moving subtropical cyclones that enter the Hawaiian area and bring persistent, strong southerly winds along with heavy showers and gusty winds. Under trade wind conditions, there is often a pronounced moisture discontinuity between 4,000 and 8,000 feet that can cause a temperature inversion, causing low pressure systems to form and resulting in high temperatures in Hawaii.

9. Temperature Inversion

An inversion is an atmospheric phenomenon in which the temperature increases with increasing height, rather than decreasing as it would normally. This temperature inversion typically occurs at heights between 4,000 and 8,000 feet, and is embedded in the moving trade-wind air in the Pacific Anticyclone. The inversion acts to create a lower, more moist layer of air below the inversion, and a higher, more dry layer of air above the inversion. It also tends to suppress the vertical movement of air, restricting cloud development to the layer beneath the inversion. This can have a significant effect on the temperature in Hawaii, as the temperature increases more quickly with increasing height, thus making the air above the inversion much warmer than normal. In addition, the cloud development is also restricted, which may also have an effect on temperatures.

10. Flora and Fauna

In Hawaii, high temperatures are caused by a variety of flora and fauna. The most prominent among them is the dense tropical vegetation that covers much of the islands. These plants, such as palm trees, ferns, and flowering shrubs, provide cover and act as insulation against the sun’s heat. Furthermore, many of these plants have adapted to thrive in the high temperatures of the islands. Other forms of flora that can be found on the islands include coral reefs and mangroves, which also help to regulate temperatures in the region.

Fauna are also responsible for the high temperatures in Hawaii. Sea turtles, dolphins, whales, and monk seals all inhabit the nearshore waters, which help to absorb and store heat from the sun. Seabirds and endemic forest birds, such as the ‘Apapane, create a network of warm air, which also contributes to the higher temperatures. Finally, the presence of invasive species, such as Californian shrubs and grasses, can also increase the likeliness of fires, which further contributes to the higher temperatures.

Boats on a river in Hawaii.

How to Beat the Heat in Hawaii?

1. Stay hydrated

It is incredibly important to stay hydrated in Hawaii given the strength of the sun’s rays. The Hawaiian Islands are close to the equator, meaning the sun’s rays are much stronger than the average place. As a result, the immediate solution to protect oneself from the heat is to seek out air-conditioning and stay hydrated.

However, the longterm solution to this issue is to implement tree-planting efforts which will create more shade and soak up carbon emissions, reducing global warming. This is why organizations such as ‘Go Carbon Neutral’ are actively encouraging people to plant trees.

Beyond this, scientists have pointed out that the continual heat records being broken in Hawaii is an indication of potential climate change. The UN’s Intergovernmental Panel on Climate Change has warned it may be much sooner than expected, so it is important to take action now. In some cases, this could involve changing building designs and codes to make them more sustainable, as well as making sure people stay hydrated.

Overall, the importance of staying hydrated in Hawaii cannot be overstated. Doing so will help protect yourself from the heat in the short-term, as well as contribute to a more sustainable future in the long-term.

2. Stay indoors

  1. Seek out air-conditioned respites such as malls and movie theaters.
  2. Install window coverings such as blinds, curtains, and shutters to block the sun’s rays.
  3. Invest in a personal air conditioner, either a portable one or a window unit.
  4. Plant trees or green shrubs around your home to create shade.
  5. Utilize fans around your home to circulate air.
  6. Avoid using major appliances such as ovens, dryers, and dishwashers during the day.
  7. Consider replacing asphalt surfaces in your yard with cooler surfaces such as pavers and gravel.
  8. Wear lightweight, light-colored clothing and keep as much skin covered as possible.
  9. Stay hydrated by drinking a lot of water and avoiding alcohol and caffeine.
  10. Check your local news sources for extreme heat warnings and take extra precautions if needed.

3. Use air conditioning

Air conditioning can help people beat the heat in Hawaii by providing a cool respite from the warm weather. This is an immediate solution that can be implemented without much difficulty. However, while this provides relief in the short term, long-term solutions should be implemented in order to address the root cause of the heat. Planting trees, for instance, can not only create more shade to cool the islands, but can also help to soak up carbon emissions which contribute to global warming. By taking action now, we can prevent the worst effects of climate change from manifesting in the future. And since heat mapping campaigns have been implemented to identify where tree canopies should be improved, anyone interested in helping can join organized efforts to plant trees and make a difference.

4. Wear light clothing

If you’re visiting during the summer months, the temperatures can get quite warm. To beat the heat, it is best to pack light and breathable clothing. Short-sleeved shirts and light, comfortable shorts are a great way to keep cool. Linen and cotton fabrics will help to keep you comfortable in the heat. If you plan on hiking or participating in activities, make sure to wear light, breathable fabrics such as synthetic materials. For feet, opt for sandals and lightweight shoes that won’t trap in the heat. If you’re worried about sun exposure, pack a wide-brimmed hat and sunglasses to protect your face and eyes. For colder weather, such as when you’re visiting mountain summits, pack long pants, something with sleeves, and even a light jacket or two. A great way to stay warm is to layer your clothes and make sure to pack a warm hat and gloves. Don’t forget to pack sunscreen and insect repellent as well!

5. Take a swim

Swimming is one of the best ways to beat the heat in Hawaii. Here are a few tips and tricks for how to do it:

  1. Look for a beach with optimal conditions for your desired activity. If you want to swim in calm waters, aim for a beach in the summer months when the ocean is usually calmer. If you want to experience larger waves for surfing, look for a beach on the north shore during the winter months.
  2. Make sure to check the ocean temperature before you get in. In January, the ocean temperature is usually around 72 to 76 degrees F, but it can vary depending on the beach.
  3. Bring the necessary gear. You will need water-resistant sunscreen, appropriate clothing, and any water equipment you might need, such as a snorkel, fins, and possibly a surfboard.
  4. Find a safe spot to swim. If you’re a beginner or not confident in the water, look for a sheltered beach with small waves.
  5. Make sure to stay hydrated. It’s easy to forget to drink water while swimming because you’re enjoying the water and the scenery. But it’s important to drink enough water to stay hydrated and safe.
  6. Have fun! Swimming is a great way to cool off and get some exercise in one of the most beautiful places in the world. So enjoy it!

6. Try yoga

The warm temperatures and high humidity of Hawaii can sometimes be overwhelming, making it difficult to stay cool and comfortable during the summer months. Fortunately, practicing yoga can be a great way to help beat the heat in Hawaii.

Yoga is an ancient practice that incorporates breathing and stretching exercises, which can help promote relaxation and reduce stress. When done in a hot environment, such as Hawaii, it can also help to regulate body temperature, allowing the body to cool itself. This helps you stay comfortable and relaxed even in the heat of summer.

In addition to helping regulate body temperature, yoga can also help strengthen the body and improve overall health. By increasing strength and flexibility, you can reduce the risk of injury and help your body stay cool.

Finally, by taking time to practice yoga, you can enjoy the beauty and creativity of Hawaii. Through the practice, you can explore and discover new places, and feel inspired by the natural beauty of the islands.

So if you’re looking to beat the heat in Hawaii, don’t forget to give yoga a try. Not only will it help keep you cool, but it can also help reduce stress, strengthen the body, and give you the opportunity to explore new places.

7. Meditate

Meditating is a great way to beat the heat in Hawaii. Allowing yourself to take a few moments of relaxation and mindfulness can help you to remain calm and enjoy the sunshine. By focusing on your breathing, you can increase your awareness of the present moment and reduce your stress levels. This can help you to stay cool and enjoy the natural beauty of Hawaii without the worry of heat. Additionally, studies have shown that meditating can help to reduce your blood pressure and heart rate, which can also help keep you cool in high temperatures. So, next time you’re in Hawaii and feeling the heat, take a few moments to meditate and you’ll quickly be feeling the chill.

8. Plan outdoor activities at night

Planning outdoor activities at night to beat the heat in Hawaii can be a great way to enjoy your vacation. Here are some tips on how to plan outdoor activities at night:

  1. Check the hours of daylight and aim to plan activities during the low-light hours. In Hawaii, daylight hours do not differ much from month to month and generally last from 7:10 a.m. to 6:00 p.m.
  2. Choose activities that can be enjoyed in the evening or at night, such as stargazing, whale watching, and surfing. Stargazing can be done at Mauna Kea or Mauna Loa, whale watching is best enjoyed from boats in the evening, and surfing can be done during the nighttime when the waves are usually more powerful.
  3. Make sure to wear the appropriate clothing for the activity you are planning. For stargazing and whale watching, bring long pants and something with sleeves, as well as a light jacket, since temperatures can drop significantly. For surfing, choose clothing that will keep you warm but won’t be too heavy.
  4. Be prepared for the elements. Bring sunscreen, a hat, and sunglasses to protect you from the sun. You may also want to bring bug spray, as bugs tend to be more active at night.
  5. Stay safe. Make sure you let someone know where you are going and when you expect to be back. Additionally, make sure to stay hydrated and bring enough snacks for your activities.

By following these tips, you can plan outdoor activities at night to beat the heat in Hawaii and make the most of your vacation.

9. Use fans

Fans can help to beat the heat in Hawaii by providing air circulation and cooling, as well as reducing humidity levels. To maximize the cooling effects of fans, it is important to install them in areas that are well-ventilated, such as near windows and doors, and to ensure that they are directed towards people or furniture. Additionally, fans should be placed strategically in areas that are most affected by the heat, such as in bedrooms or living rooms. Finally, fans should be used in combination with other measures, such as planting trees or installing reflective coatings on buildings, to reduce the effects of global warming on the islands.

10. Plant trees

Planting trees can play a major role in helping Hawaiians beat the heat and protect themselves from the effects of global warming. Trees provide shade and can help to reduce surface temperatures on the islands, creating a more comfortable environment for those living there. Trees also absorb carbon dioxide from the atmosphere, helping to reduce the amount of greenhouse gases that contribute to global warming. Furthermore, trees provide an important habitat for native wildlife, which can further help to mitigate the effects of extreme temperatures. Planting trees is also a cost-effective way to improve the environment and combat climate change. With the help of volunteers and organizations like Go Carbon Neutral, it is possible to plant thousands of trees in a single day, helping to cool the islands and create a healthier, more sustainable environment.


Mahalo For Sharing Your Aloha
National Weather Service