1. Mountain Weather MITOC Winter School 2002 Robert Zeithammer

2. Why Weather? October 12, 1999 …top of Mount Madison

3. Weather Changes January 1: Temperature 3 degrees; Snow, freezing fog, wind chill –50 Visibility: 100 feet

4. Moosilauke Skiing Trip, Winter School 2001

5. Weather Safety Check the forecast (but don’t rely on it!!!) –http://met-www.cit.cornell.edu/cgi-bin/fcst?NH004 –http://www.mountwashington.org/weather/today.htmlhttp://www.mountwashington.org/weather/today.html Daily weather-report Higher-summits forecast Backcountry conditions Stay alert to weather changes –Clouds and winds provide big hints Come prepared for the worst!!!

6. What’s “worst”? 30 F, heavy rain, any wind a bonus -10 F, 60 MPH wind : feels like –50F Mount Washington at the confluence of three major storm- tracks. In the Whites, wind is the biggest concern. –It makes you cold (wind chill) –It knocks you over (70 MPH enough) –It likely makes visibility unreliable –It increases avalanche danger

7. Exact #s unimportant. Basic idea crucial!

8. Presidential Reverse, February 2001

9. Mountains get bad weather

10. Cirrus Clouds High altitude clouds; good weather, possible rain in 12-24 hours for some types

11. Cumulus Clouds Nice weather, but keep an eye out

12. Nimbostratus Clouds Lower (2000m) clouds Rain or snow coming soon

13. Cumulonimbus Clouds with vertical growth (“Anvils”) (May not see the anvil when close) Heavy rain, snow, hail, lightning!

14. Blue Skies Good weather has its downsides too: The Sun (it’s a mass of incandescent gas…) Sunburn can be serious –Light and U/V reflected by snow and ice –Sunburned retinas and mouths are not fun Sunscreen, long-sleeved clothing, and sunglasses will make you happier

15. Weather Summary Check forecasts, check the skies often –Neither is a perfect predictor, so be prepared. Take-home lesson: STAY ALERT. Weather changes rapidly. When in doubt, RETREAT!!!