Just how rainy is Hilo?

[terracore]

I would MUCH rather endure an inch of Hilo rain that falls in a half day followed by a nice long sun break than an inch of SE Alaska rain that takes 30 days to fall followed 30 days of snow and still waiting weeks for the next sun break.

[hotzcatz]

And if your half inch of rain was yesterday, you could have gotten it done in much less than half a day.

[Jungjohann]

Originally Posted by hotzcatz

And if your half inch of rain was yesterday, you could have gotten it done in much less than half a day.

Wailea was looking like Hilo on steroids for about an hour yesterday evening. Ua nui

[StarfishKey]

I realize a lot has been said about this, but there is still an aspect of the Hilo weather that I am unsure about. I find the wetness of Hilo very attractive for the ability to collect rainwater, and to grow tropical plants, and thus be reasonably self-sustaining. (It would seem like the soil isn't completely terrible there?)

It seems like the rain in Hilo is much like the rainy season in Miami, only year-round. At the height of the rainy season, Miami can regularly rain 3 times a day, which I loved when I lived there. Although the Florida Keys are drier, here in the Keys the soil is very rocky and fast-draining, which keeps flooding to a minimum despite our elevation at below-flood in most locations.

But there is a big difference between SFL rain, and the rain one gets in states up North. Up North, the sky is gray most of the year, with very little sunshine. In SFL, sure you may get rain, but unless there is an actual tropical storm, generally the rain is falling from a single cloud in an expanse of otherwise blue sky and the sun shining through it as it's falling, or it is a bunch of clouds in a torrential downpour, and then the clouds move on and it's sunny 20 minutes later. Rainbows are extremely common.

So yes, it's rainy nearly every day on average, but is there at least an hour of SUN in the day on nearly every day? Or does the sky stay overcast all the time? I love the humidity and the rainfall, but if I cannot feel some sun on me for even a brief time most days out of the week, I will tend to get depressed. It's hard to tell from the charts above (although thank you for that, I am one who can never get too much information!), because they will classify a day with 20 minutes or an hour of sun as being a day "without sun" it seems. South Florida does not have such a thing as cloud covering 90-100% of the sky unless we have a serious system overhead. So even though one might get 10 inches of rainfall in an average Miami September, one still sees sun basically every day. (And that is pretty much my ideal weather - some sun and some rain every day, often at the same time.)

Also, does this heavy rainfall mean lots of flooding, mudslides, and dangerous conditions? I understand that mold and mildew are a factor, and that that poses a danger to health. And there may be VOG, which also concerns me. So air quality may not be the best. But are people commonly in physical danger just stepping out onto the street? Again, to draw a comparison, Miami and the Keys are very flat, so there is no danger really in the rainy season of landslides. But it is common in certain areas of Key West and Miami Beach for people's cars to float away inside a parking garage or down the street, in a typical afternoon storm that doesn't even make the news.



This may sound silly, but I wonder if I would get cold. If one is constantly getting wet, and the average temp hovers at 80, that is much colder than the average high of 91 in inland SFL during the rainy season months. And where I lived inland in Miami, the temp was exactly 93 degrees every single day for 5 months every year.

Note that the above numbers given appear to be skewed toward the bottom of the range. Although it is stated that Hilo gets 130 inches per year, according to the NOAA (which is a much more accurate source than wikipedia will ever hope to be):

"Within the city of Hilo, average rainfall varies from about 130 inches a year near the shore to as much as 200 inches upslope. The wettest part of the island, with a mean annual rainfall exceeding 300 inches, lies about 6 miles upslope from the city limits. Relative humidity at Hilo is in the moderate range, however, due to the natural ventilation provided by the prevailing winds, the weather is seldom oppressive."

So 130 inches sounds like it is only going to apply to the driest part of Hilo. It only gets wetter from there.

It is stunning to me that with all this rain, the humidity is far lower than in Miami, which again makes me a bit concerned that I would often feel cold: Average humidity ranges from 71-76% in Hilo, where by contrast Miami humidity during its rainy season averages from 91-96%! 71% humidity in 90 degrees might be close to ideal for me, but 71% humidity in 80 degrees while wet might be a bit cold.

One thing that is a problem in Miami is that during the rainy season, you are often soaking wet and then step into a way-over-air-conditioned building that feels like a freezer for workday or errands. But I see a lot of discussion of tradewinds, making it sound like many buildings do not have A/C? So would you say that Hilo people have a lot of transitions from soaking wet to freezing as they run errands in stores, or say work at a school? Or is this not a problem because A/C either doesn't exist in many public buildings, or is used moderately so it doesn't feel like a meat locker? (I'm getting the impression there might be many schools around HI that don't have A/C...?) Ideally I guess A/C would be available in these buildings for comfort and to prevent mold, but not set at 75 degrees or lower where it is going to make a wet person miserable...

[Arktikos]

Sunshine hours per year for Hilo are much lower than Miami: 1800 hours for Hilo and 2900 for Miami.

I had a friend from SE Alaska come over and spend several months at my Puna place, looking for some sunshine after the constant wet/overcast we get here, and she expressed her disappointment on more than one occasion. No, you will not necessarily experience a bit of sun on every day in the Hilo area.

It's true that in the general Hilo area, the airport recording station is about the driest location. Downtown is about 10 inches more, and the up slope neighborhoods, such as Waikea Uka, are much wetter.

The only time I've felt cold is on a dry, early morning or late night in the winter, with a north wind. It can get down in the low 60s, or even high 50's briefly. But, I'm up about 600-700ft, which is a tad cooler than sea level.

Public buildings are air conditioned, and excessively so for my tastes. I never feel a desire for AC anywhere on the windward sides of the islands. Sometimes it's too hot while driving a car, but then I take my shirt off-problem solved.

Flooding can occur, but the area is fairly well adapted to it. Slides can sometimes block the major highway circling the island, but these are dealt with quickly. I haven't heard of anyone loosing a house to a slide. Most of the ground is porous lava that drains rapidly.

[Arktikos]

Originally Posted by StarfishKey

So yes, it's rainy nearly every day on average, but is there at least an hour of SUN in the day on nearly every day? Or does the sky stay overcast all the time? I love the humidity and the rainfall, but if I cannot feel some sun on me for even a brief time most days out of the week, I will tend to get depressed..

Copy and pasting something I posted in the weather section here at CD:

Brian B's Climate Blog: Dreary Weather

...Since the values for each data set are from 1 to 10, the range of values from adding them all together are 3 to 30. Only a few places received a maximum dreariness index score of 30. They include: northwest Washington state, southeast Alaska, and windward Hawai'i...

[Irish Eyes_Mrs. Z]

Interesting link! Thanks for sharing it.

[leilaniguy]

Of course this chart leaves out temperature, "The miserability index".

[hotzcatz]

Due to the high cost of electricity, there isn't a lot of A/C in Hilo.

However, it sounds like you may find it cold if you're used to warmer temperatures. Folks wear jackets and sweaters and such during winters if they are from around here. Folks from the mainland are usually the ones wearing shorts and tee shirts when everyone else is bundled up, so it's all what you're used to. When my friend from Thailand visits, he's always cold, but a sweater is enough to keep him warm.