Know how: Weather 101, Basics - Sail Magazine

Know how: Weather 101, Basics

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Overview

The first thing to know is that “Weather 101, Basics” is a science course. Its goal is to prepare boaters for a second course launching later this year called “Weather 202, Advanced.” Taken together, these classes are designed to teach boaters to become their own weather forecasters.

It may be science, but that doesn’t mean that the principles of weather cannot be rendered using plain language. When veteran marine forecaster Chris Parker talks about the weight of atmosphere, he’ll let you know that “air is pretty heavy.” Discussing energy transfer on a global scale, Parker notes, “There’s more friction on land...so there is less wind.” What is a front? “A front is simply a leading edge between dissimilar air masses,” he answers.

Parker has been advising cruising boaters for more than 15 years, earning a reputation for precision forecasting, initially in the Bahamas and Caribbean Sea. For example, the Exumas are an archipelago in the Bahamas that is 130 miles long, yet Parker’s forecasts divide these islands into northern, central and southern sectors for localized predictions. Nobody else cuts it so fine.

Today his weather routing is world-wide. In fact, while we were taping this course, Parker was shepherding two boats across the Pacific.

“Weather 101, Basics” is a course for ambitious cruisers, who want the knowledge to perform reality checks on forecasts received from afar and the ability to craft their own when onboard technology goes dark.

Course Syllabus

MODULE 1, Energy Basics

  • Introduction
  • Weather is Earth's mechanism to redistribute energy
  • Atmosphere has weight (mass, momentum)
  • Warm air rises
  • Moist air has latent (potential) warmth
  • Air moves horizontally and vertically
  • Basic concepts like convergence/divergence
  • Motion of air, Coriolis effect
  • Energy transfer occurs on many scales, here we discuss Global Scale energy transfer

MODULE 2, Synoptic-Scale Meteorology

  • Introduction
  • Air-mass classification
  • High and Low-pressure systems
  • Fronts & Trofs
  • Front & Front summary

MODULE 3, Folklore

  • Red sky at night
  • Red sky in morning
  • Halo rings moon or sun
  • Mackerel sky and mares’ tails

MODULE 4, The Spin Zone

  • Upper-air weather and how it influences surface weather and patterns
  • Convergence and Divergence in 3-dimensions
  • Vorticity (spin)
  • Identifying upper-air (500-millibar) patterns and their surface effects
  • Real world example of upper-TROF triggering a (non-Tropical) Hurricane Force Low pressure system.

MODULE 5, Forecast resources

· Weather Bell

· Weathermodels.com

· Tropical tidbits

· Spot weather

· Sirius XM

· Weather apps on mobile device

chrisParker

Instructor Biography

We kid you not. When Chris Parker was four, his ambition was to be a TV weatherman. He even studied Meteorology for a couple years at college in Vermont, but he ended up with a degree in Business.

Parker grew up in a boating family, however, and it got the best of him. In mid-career, he chucked his business life to cruise the East Coast, Bahamas and Caribbean. For 12 years, he and his partner and Wizard the cat lived like seagoing gypsies. “We took pride in traveling an average of 5,000 miles each year while burning an average of about 50 gallons of diesel,” he says. “We almost always sailed from place to place, and often sailed on and off anchor.”

Parker tells the story of why he came back to his childhood dream of growing up a weatherman. It was a case of self-defense, and it happened in the Bahamas in the winter of 2000:

We were caught several times by nasty cold fronts which arrived with no warning. Nasty weather surprises were not supposed to be part of retirement in paradise! Being a hard-headed "type-A" personality, I figured I had to be able to do a better job predicting weather than the forecasts I'd been relying on. I began downloading and analyzing weather-fax charts and text forecasts and generating a forecast for our use. Soon after, GRIB files became available and they were a huge help, providing precise (though not always correct) input.

When discussing plans for upcoming days with cruising friends, the conversation inevitably turned to weather. Friends asked why we wanted a protected anchorage on a particular afternoon, or why we decided to go northeast to Eleuthera from Staniel Cay instead of continuing southeast down the Exumas. I said our decisions were based on the weather forecast, and when the forecast I was using turned out to be correct time and time again, friends began asking where I got my forecast. Before long, friends were hailing me on SSB and VHF radios for forecasts.

Parker went pro. He became chief forecaster for the Caribbean Weather Center after its founder David Jones died in late 2003. He continued in the position until late 2010, when he founded the Marine Weather Center, based in Lakeland, Florida, where he broadcasts to small private vessels all over the world using powerful radio equipment and the Internet.

What You Will Learn

“Weather 101, Basics” explains how weather works. These are the fundamental principles that will prepare you for “Weather 202, Advanced,” coming later this year. Together these courses are designed to teach mariners how to confirm the accuracy of commercial forecasts and be their own weather routers.

Chris Parker’s Forecast Philosophy

Weather forecasters tend to be opinionated, and some might say arrogant bunch. We like to be right. I see technical forecast discussions time and time again, which mention the possibility/plausibility for severe weather, but, since the forecaster’s objective is to be "right" (to produce a single forecast with the greatest chance of being correct), they fail to warn forecast recipients of potentially-severe weather. I have a different objective.

I try to make sure you are not surprised by the weather - especially that you're not surprised by inclement weather. Occasionally that means my forecasts for inclement weather fail to verify, but I'd much rather have it that way than to have clients surprised by nasty weather. Of course, I can't anticipate all inclement weather, and I encourage clients to use as many forecast sources as they wish. I encourage dialogue.

While I may suggest you consider sailing a specific route for most-favorable conditions, my routing advice goes way beyond that. I try to consider unique needs of each client. I’ve worked with physically disabled sailors, vessels with young children onboard, engine-less vessels, serious racers, delivery crews, day-sailors, vessels on Atlantic, Pacific and Indian Ocean crossings, fishing vessels, tugboats, surfers, airplanes, etc.

Each client has different goals and desires different “ideal” weather conditions. I try to tailor my entire interaction with a vessel to the needs of that vessel, but ultimately you must make your own decisions. However, I may recommend tactics I might use in a situation similar to yours, including how to pick-up a favorable wind-shift to win a race, or how to delay the need to jibe until after sunrise, or how to deploy available gear to steady a ride downwind, or to consider an alternate destination/anchorage given the expected conditions.

Weather 101, Basics" is the precursor to "Weather 202, Advanced," to be released later in the year. The course is priced at $275, but we a preselling it with a $25 discount using promo code "WeatherVIP.

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