Weather for Climbers Andy Haner Forecaster NOAA National
Weather for Climbers Andy Haner Forecaster NOAA – National Weather Service, Seattle
Who is the National Weather Service? Mission Provide Weather, Hydrologic, and Climate Forecasts and Warnings for the United States, its Territories, Adjacent Waters and Ocean Areas, for the Protection of Life and Property and Enhancement of the National Economy. • Partners/Customers – Area Media – Emerg Mgmt Community – Aviation and Water Mgmt – Mariners and Schools – Businesses / Public – Fire / Law Enforcement – Military and Transportation – Utilities and Health Care – Essentially Everyone!
NWS Seattle-Tacoma NWS Seattle. Tacoma, WA
Important Terminology NWS Weather and Flood Bulletins Weather/Flood Outlook Weather/Flood Watch Weather/Flood Warning/ Advisory
What do these Warnings Mean anyway? Winter Storm Warning • Snow, Ice and/or Strong Winds • Lowlands – 4+” snow • Mountains – 12+” snow Winter Weather Advisory Lowlands – 1 -3 inches Mountains – 6 -11 inches Blizzard Warning • Snow Combined with Strong Winds of 35 MPH or more and visibility less than 1/4 mile Avalanche • #2 Weather-Related Killer in Washington
What is “Chance of Precipitation”? • Probability of >=0. 01” of precipitation in a 12 -hour period • Yes, it’s a “low bar” for the mountains of the Pac NW • Precipitation Amount is of more value
Sources of Weather Information • National Weather Service • Northwest Avalanche Center • “Secret Squirrel” sources – what the meteorologist looks at
National Weather Service • Point-and-click Forecast • Mt. Rainier Recreational Forecast • Area Forecast Discussion
weather. gov/seattle
How to get the Mt. Rainier Rec Forecast: weather. gov/seattle
weather. gov/seattle
Northwest Avalanche Center • Focus on cold season Mountain Weather and avalanche danger (staffed 9 months each year) • U. S. Forest Service program co-located with National Weather Service, Seattle • Large portion of funding is from private donors via Friends of the Northwest Avalanche Center • www. nwac. us
“Secret Squirrel” sources – where the meteorologist goes • UW WRF • Radar • Satellite • Ensembles: GEFS Plumes
Ensemble Plumes (search “GEFS Plumes”)
https: //ensemble. ucar. edu
Mountain Micro-Climates • Puget Sound Convergence Zone • Lightning • Favored formation locations • Seasonal Trends • Summertime AM vs. PM lightning • Marine Layer effects • Wintertime East Winds, inversions
Puget Sound Convergence Zone
Puget Sound Convergence Zone Rain, Snow, Hail, Thunderstorms, Drizzle
Monitoring Weather with Radar http: //radar. weather. gov Access to every NWS radar nationwide (about 175)
http: //radar. weather. gov So what’s the difference between Composite and Base?
Can Detect Different Levels in Atmosphere • Base Reflectivity: Displays returned energy from only the lowest elevation scan (0. 5 degrees) • Composite Reflectivity: Displays the strongest returned energy from any elevation angle over a location Thunderstorm Example
Mountain Range Composite sees over the mountains, to some extent Base only sees as far as the mountain
Mountain Example Base Composite
Temperature Inversions – East Winds
Where is the path of least resistance? H
Stevens Pass Paradise – 55 degrees Wenatchee Snoqualmie Pass – 25 degrees Ellensburg Mount Rainier Yakima Mount St. Helens Columbia Gorge The Dalles H
During East Wind • Snow levels tend to be lower in the passes than away from the pass • Mount Si vs. Snoqualmie Pass?
East Wind Location of Stronger East Wind
Fraser Outflow Location of Stronger Wind
Lenticular Clouds – First Sign of Trouble Not a lenticular!
Lenticular Clouds - Schematics
When Lightning Strikes
What's Up!
Playing the Odds � � � � The odds of getting struck by lightning in the U. S. in any single year is 1 in 700, 000 The odds of being struck in your lifetime is 1 in 5, 000 Chance of dying in an airplane accident: 1 in 354, 319 Chance of dying from choking on food: 1 in 370, 035 Odds of bowling a 300 game: 11, 500 to 1 Odds of injury from shaving: 6, 585 to 1 Odds of getting a hole in one: 5, 000 to 1 Odds of injury from using a chain saw: 4, 464 to 1
Lightning Stats � � � � A single lightning bolt is about 50, 000°F or 5 times hotter than the surface of the sun. A lightning bolt is anywhere from 1, 000 to 1, 000, 000 volts and between 10, 000 and 200, 000 amps. Or about 215 k. Wh (kilowatt hours). Positive strikes are on average 5 times more powerful than negative strikes. The average lightning bolt could light a 100 watt light bulb for about 3 months. The average lightning bolt is 6 miles long. The thickness of a lightning bolt is about the size of a silver dollar. It only looks bigger because it is so bright. A lightning bolt is made of a series of strokes from about 3 to 20, with an average of about four. The duration of each lightning bolt can vary, but typically average about 30 microseconds.
Lightning Oddities � � � Many survivors of lightning strikes report that right before being struck by lightning their hair was standing on end and they had a metallic taste in their mouth. Lightning causes objects to explode because it instantly turns any water to steam. This includes concrete, trees, asphalt and clothes. It’s been known to blow the clothes off people due to the sweat/water instantly vaporizing creating a steam explosion. About 1% of all lightning deaths in the U. S. are a result of people talking on a corded phone during a thunderstorm. The U. S. Agricultural Department estimates 80% of accidental livestock deaths are a result of lightning strikes. Park ranger Roy Sullivan was struck by lightning seven times between 1942 and 1977.
Roughly 10 -20% of lightning flashes are cloud to ground.
Bolt from the Blue The longest bolt ever recorded crossed an electrifying 118 miles in the Dallas-Ft. Worth area.
Multiple strokes
Where will it Hit? • More evenly spread in humid environment of eastern U. S. • Three times more likely to strike a mountaintop in drier western U. S.
Lightning Stats
Ground Current
Norway – August 29, 2016 Reindeer huddle together during storms
100, 000 volts
Minimize contact with ground Stand on balls of feet Stand with feet close together Put your feet together (or stand on one leg!) 100, 000 volts
Lightning Advice � Move to a safer location � Get off the ridge to a lower elevation � Stay away from tall trees � Get to a depression/low spot � A vehicle or building is safest � � Groups: Space yourselves out (50 Feet) Crouch low, with feet together, minimizing contact with the ground. You can use a pack to sit on, but never lay on the ground. If you feel your skin tingle or your hair stand on end, immediately crouch low to the ground. Make yourself the smallest possible target and minimize your contact with the ground. Stand on balls of feet
Lightning Scenario Any interesting experiences? ?
PM T-Storm Firing Zones
When do Climbers get in Trouble? Month # of SAR Weather Request: 2012 -2016 January 8 February 1 March 17 April 2 May 7 June 29 July 15 August 20 September 13 October 5 November 5 December 0
When do Climbers get in Trouble? Month # of SAR Weather Requests: 2012 -2016 January 8 February 1 March 17 April 2 May 7 June-uary 29 July 15 August 20 September 13 October 5 November 5 December 0
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