top of Sonora Peak. Pay careful attention to the elevations in which you’ll be traveling, and plan accordingly. Thunderstorms in the High Sierra (anything above 6,000 feet) are especially common from July to October but can happen in any other month as well. Always pack a waterproof (or very water-resistant) shell, a warm layer (like fleece, not cotton), and a warm hat.
The summer hiking season, depending on snowfall, generally extends from early April to late October. But there’s also a best time for every hike. For hikes set at the 5,000-foot elevation mark and under, wildflowers will be most abundant April through June. Hikes at this elevation are also good late-season hikes (October and November), depending on the current year’s storm cycle.
For hikes above 5,000 feet, you’ll have to watch the snowpack carefully to best time your hike. Generally, the trail is clear of substantial snowpack between the 5,000- and 8,000-foot elevation marks as summer rolls into late June; by July, the meadows and mountainsides between these elevations are covered in beautiful wildflowers. For hiking above the 8,000-foot mark, I recommend August because it is generally the warmest month and, if you’re lucky, you’ll catch the wildflowers and miss the mosquitoes. But never expect to be lucky. September is another perfect month to enjoy hiking above the 5,000-foot mark, but take note that the wildflowers will most likely be burned out below 8,000 feet (if not 10,000 feet). If you plan to exceed 10,000 feet in elevation, always expect to be cold no matter what month you’re hiking. As a rule of thumb, the temperature decreases about three degrees with every 1,000 feet of elevation gained. And as you gain in elevation, the likelihood of wind increases also.
ALTITUDE SICKNESS
Nothing ruins an outing more often than the body’s resistance to altitude adjustment. The illness is usually characterized by vomiting, loss of breath, extreme headache, lightheadedness, sleeplessness, and an overall sick feeling. When traveling to a higher altitude, give your body a day or two to adjust to where there is less oxygen, hotter sun, and less air pressure. Drink plenty of water, and lay off the alcohol. Wear sunglasses and sunscreen. It’s that easy. (As always, if serious symptoms persist, locate the nearest emergency room or call 911.)
LIGHTNING
Get an early start on all hikes that go above tree line. Violent storms are common in June, July, and August. Try to reach high-altitude summits by 1 p.m. and turn back when the weather turns bad. If you are caught in a lightning storm above tree line, stay off ridgetops, spread out if you are in a group, and squat or sit on a foam pad with your feet together. Keep away from rock outcroppings and isolated trees. If someone has been struck, be prepared to use CPR to help restore the victim’s breathing and heartbeat.
HYPOTHERMIA
Hypothermia occurs when your core body temperature becomes dangerously low. This condition can occur at any time of the year, and cold temperatures, wind, and rain and snow set the stage for complications. Look for signs of shivering, loss of coordination, and loss of judgment.
Preparation is your best defense against getting cold to the core. Remember the mantra “wet is not warm” to prevent hypothermia.Keep your inside layer as dry as possible.
SWIFT WATER
Mountain streams can be dangerous during high snow runoff in May and June. Even a narrow stream may be deep and fast, as well as cold. Stay back from the banks of streams and rivers, especially if you cannot see the bottom. Provide proper supervision for children who tend to be attracted to water. Rocks at the streamside and in the stream are often slippery, and water beneath them may be deep. Powerful currents in streams can pull people underwater and pin them below the surface. In case of a flash flood, climb to safety.
Water
HOW MUCH IS ENOUGH? Well, one simple physiological fact should convince you to err on the side of excess when deciding how much water to pack: A hiker working hard in 90-degree heat needs approximately ten quarts of fluid per day. That’s 2.5 gallons—12 large water bottles or 16 small ones. In other words, pack along one or two bottles even for short hikes.
Some hikers and backpackers hit the trail prepared to purify water found along the route. This method, while less dangerous than drinking it untreated, comes with risks. Purifiers with ceramic filters are the safest. Many hikers pack along the slightly distasteful tetraglycine-ñhydroperiodide tablets to debug water (sold under the names Potable Aqua, Coughlan’s, and others). I have used the SteriPEN with excellent results. Lightweight, compact, and battery-operated, the device uses ultraviolet light to render harmful microbes sterile.
Probably the most common waterborne bug that hikers face is giardia, which may not hit until one to four weeks after ingestion. It will have you living in the bathroom, passing noxious rotten-egg gas, vomiting, and shivering with chills. Other parasites to worry about include E. coli and cryptosporidium, both of which are harder to kill than giardia.
For most people, the pleasures of hiking make carrying water a relatively minor price to pay to remain healthy. If you’re tempted to drink found water, do so only if you understand the risks involved. Better yet, hydrate prior to your hike, carry (and drink) six ounces of water for every mile you plan to hike, and hydrate after the hike.
The Ten Essentials
ONE OF THE FIRST RULES OF HIKING is to be prepared for anything. The simplest way to be prepared is to carry the ten essentials. In addition to carrying the items listed below, you need to know how to use them, especially navigation items. Always consider worst-case scenarios like getting lost, hiking back in the dark, breaking gear (for example, a broken hip strap on your pack or a water filter getting clogged), twisting an ankle, or experiencing a brutal thunderstorm. The items listed below don’t cost a lot of money, don’t take up much room, and don’t weigh much, but they just might save your life.
WATER: Durable bottles and water treatment such as iodine or a filter
MAP: Preferably a topo and a trail map with a route description
COMPASS: A high-quality model
FIRST-AID KIT: A good-quality kit whose contents you’re familiar with and that contains instructions
KNIFE: Preferably a multitool device with pliers
LIGHT: Flashlight or headlamp with extra bulbs and batteries
FIRE: Windproof matches or lighter and fire starter
EXTRA FOOD: Always bring more than you need.
EXTRA CLOTHES: Rain protection, warm layers, gloves, and a warm hat
SUN PROTECTION: Sunglasses, lip balm, sunblock, and a sun hat
First-Aid Kit
A TYPICAL FIRST-AID KIT may contain more items than you might think necessary. These are just the basics. Prepackaged kits in waterproof bags (Atwater Carey and Adventure Medical make a variety of kits) are available. Even though there are quite a few items listed here, they pack down into a small space:
Ace bandages or Spenco joint wraps
Adhesive bandages
Antibiotic ointment (Neosporin or the generic equivalent)
Benadryl or the generic equivalent, diphenhydramine (in case of allergic reactions)
Butterfly-closure bandages
Epinephrine in a prefilled syringe (for severe allergic reactions to bee stings, usually by prescription only)
Gauze (one roll)
Gauze compress pads (a half dozen 4 x 4-inch pads)
Hydrogen peroxide or iodine
Ibuprofen or acetaminophen
Insect repellent
Matches or pocket lighter
Moleskin or Spenco Second Skin
Sunscreen
Whistle (It’s more effective at signaling rescuers than your voice is.)
The following items are optional but worth their weight (make your own lists for different seasons and keep them in your