Last week's elevation storms were the most extreme in memory. Folks in Kingston and Saugerties (altitude 200 feet) and even Woodstock (550 feet) got only rain. Meanwhile, astonished homeowners in Phoenicia (950 feet) or Willow (1,100) got 44 inches of snow between Tuesday and Saturday: three-and-a-half feet. Nearly half of Central Hudson's customers lost power at some point. I think that company deserves applause for their good job, considering the extensiveness of the blackouts.

Many in our area - on tertiary roads leading up from Lake Hill, Willow, Manorville and other places - have homes above 2,000 feet. I don't know how much snow they got; we still haven't heard from them.

These were quirky storms. They dumped feet of snow even on many lower elevations, like around New Paltz and Fishkill. Of course, altitude is relative. To Colorado residents, whose lowest point is 3,315 feet, New Paltz's 345 feet must seem like the Dead Sea. And yet that elevation matches the very highest point in all of Florida, Britton Hill.

We were reminded of the importance of elevation, and we'll soon experience it again. Kingston's trees are in leaf the third week of April; Hunter and Tannersville's trees aren't green until mid-May. In a real sense, those places have six fewer weeks of summer than does Saugerties.

The high elevations have advantages, of course. They used to be the traditional retreat for New Yorkers fleeing the City's summer heat and haze, in the bad old pre-air-conditioning days.

Temperature and absolute humidity both fall quickly with altitude. It's the wonderful adiabatic lapse rate, which amounts to a four-to-five-degree drop per thousand feet, depending on humidity. Result: Kingston and Saugerties are typically a degree warmer than Woodstock, three to four degrees warmer than Phoenicia and four to five degrees warmer than most homes in Lake Hill or Willow. They're 12 degrees warmer than Hunter's highest ski slopes.

Each thousand-foot rise also boosts the Sun's ultraviolet intensity by four percent. Compared with New Paltz, Hunter's skiers get 15 percent more UV on top of the doubling created by snow's high (90 percent) UV reflectivity. No wonder snowboarders have burnt Rudolph noses. This effect is much more pronounced now, since being around snow in March, when the Sun is much higher, produces a burn three times faster than it does in December.

As I mentioned here previously, radiation cranks up with elevation, too. Each of us gets about 360 millirems of radiation yearly, which may account for many of the spontaneous tumors that have always plagued our species. Three hundred of this comes from natural sources - a mix of radon from basements below and cosmic radiation from space - the rest mostly from medical X-rays. But every 100 feet higher your home is located brings you an extra millirem a year from space. People living in Tannersville, up at 2,000 feet, receive 20 more annual millirems than those in friendly Saugerties. This elevation radiation can be significant, and explains why professional pilots and flight attendants suffer a one percent greater lifetime cancer risk.

Altitude affects water's boiling point, too. At the Rondout in Kingston - elevation eight feet - water boils at 212 degrees, and tea is nice and hot. In Woodstock, elevation 550 feet, water boils at 211 degrees. It's 208 degrees in Tannersville, and 204 degrees in that snack shop atop Hunter Mountain. Is that noticeable? Definitely. Since water is 80 times denser than air, small changes in water temp are obvious, as anyone with a hot tub can tell you. The "small" four-degree difference between a 98-degree Jacuzzi and one that's 102 degrees is subjectively felt as the difference between nicely warm and tingling hot.

The highest place you can reach around here is the hike to the top of Slide Mountain, at 4,200 feet. Or us lazy types can take the chairlift up Hunter and virtually reach 4,000. Do it now and you can check out the five to six feet of snow that they got last week. Let's hope, for everyone's sake, that it melts slowly.