Hey all, I am new to the forums and when I seen this thread I really wanted to submit my first post.
Bakersfield, California is routinely over 105 degrees Fahrenheit in the summer. Somedays it is over 110. This I call home. I started bicycle commuting to lose weight. When I started three months ago I weighed 310 pounds and I am 5'10". Now I weigh 292.
I work in the oilfields as an electrician. So I spend my days in that heat, being "morbidly obese" doing an extremely physically demanding job. On top of that I chose to add on a 6.5 mile commute each way.
At work, in addition to my duties as an electrician I am a "Behavior Based Safety" coach. Keeping cool and hydrating is a huge focus of this program during the summer. I have drawn some parallels over from the oilfields to cycling.
In the oilfields we are told to "cab up" at our discretion. Meaning when we start feeling tired from the heat we get in the truck and drink water, electrolyte replacement and cool down.
My morning commute is warm but very manageable. I do drink coffee, but since it is a diuretic (makes your body lose more fluid than you just drank), I make sure i drink a whole lotta water at work. My partner and I go through a 5 gallon jug in one shift. I also use Sqwincher electrolyte replacement. If I feel exhausted I take Tablytes by Elete. I fill my water bottles and drink the during the 1 hour vanpool ride to my bike.
Once I am on my bike preparing for my 6.5 mile commute home in 105 degrees, I have taken in about 36 ounces of water and an electrolyte replacement. I refill with water at starbucks and start my ride. I move at a moderate pace that I can sustain the whole way, about 14 mph. I also wear a bandana under my bike helmet, and sunblock. I wear my work clothes which draws alot of looks. I wear a fire ******ant t-shirt with long sleeves and blue jeans.

Have lived in Tucson, AZ for 33+ years. Now retired, but commuted to work year-round for over 16 years every day.
Warmest I've commuted in: 117 degrees, 2% humidity.
Wet cycling cap, wet bandana around neck, one bottle of cold water and pedal home.
Have also done a century on our tandem in Maryland in summer: 98 degrees, with 98% humidity.
Neither rides were not fun, but do-able . . . Hard to find a shade tree in the desert . . . if you're lucky a telephone pole or saguaro cactus could give you a brief respite.
We've got distances here with 50 miles of no shade, no convenience stores, no people; a-h-h-h-h but we've got sunshine year 'round!
Pedal on!
Rudy/zonatandem

Since illness from heat has come up, please note this can be a very serious condition. Heat stroke, the most severe form of heat caused illness, has about a 10% fatality rate. Some helpful sites on what to watch out for etc.:
Heat Exhaustion and Heatstroke: What You Should Know
Heat Stress (NIOSH site)
Safeguarding against heat hazards (OH&S site)

I have never used one, but cooling vests are sometimes used to prevent workplace related heat illness. Also, I recall some cyclists in RAAM have used some sort of cooling vest while crossing the desert and other hot areas in this coast-to-coast race across the USA. Some cooling vest vendors are Cool Vest, Core Cooler, and TiMountain. Since these seem to work by evaporation, I would think these would not be as effective in high humidity, low airspeed conditions when evaporative cooling via sweating is also less effective. I wonder if anyone makes an ice-based cooling vest? Edit: The OH&S site mentions cooling vests with ice packs, so there should be some available.

Well, this is messed up. I got sick after the heat wave, as in "I got cold". The building I work in is very cold in the morning, before the space fills up with people it's probably low 60s (the A/C system is screwy, doesn't maintain steady temperatures). So when I walk in in the morning hot and sweaty it's almost a thermal shock, I get goose bumps. Although, I wash up and change clothes within 15 minutes it's probably long enough to get sick. From now on I will change my jersey to a long sleeve top before entering the building and put a skull cap on (I have 1mm haircut so I feel the cold).

Adam

How do you get sick from cooling down? That is odd.

But you're in Malta... stop complaining. It's paradise.

With that much difference in temperatures it's like being throw into ice cold water. This isn't healthy.

Being from Bakersfield myself, I am baffled by how you do it. Anytime past 8am and before 7pm is just unbearable for me. I routine lift weights within my garage which reaches much higher temperatures than outside, yet I find that easier to endure as it is the sun which kills me. And wearing jeans? That's morbid.

I would definite like to commute by bike, but until I get to your level of heat tolerance, I'll stick to the car

Living in FL I have learned that you don't ever beat the heat. Which ever way you turn, the heat beats you. You either ride like you are climbing mount everest or you don't ride at all. I choose to climb hopping that winter will come.

LOL, yeah working in the oilfields builds your heat tolerance rather quickly. I do call for a rescue ride when I have overworked myself during the day. Yesterday I was on a jackhammer all day and was tore back. For safety sakes I called my wife and she picked me up. Luck would have it as we were driving down the road (please forgive me) in 106 degrees, we seen a cyclist pushing his bike and talking on his cell phone. We stopped in front of him, poor kid was sweatin and upset. Some cager threw something at him and just then his rear tire flatted. I grabbed up his bike and threw it on the back of the PT loser... I mean cruiser.... which has a bike carrier, and took him home. My wife asked if there was some kinda code among bike commuters. I like to think so!