Friday, January 1, 2016

Article Categories


GRIB School (February 2021)
US Weather Map File Names (July 2020)
SCATSat — The Indian Scatterometer (March 2020)
Evaluating a Weather Forecast — Slides and Notes (February 2020)
Forecasting and Evaluating Local Weather (February 2020)
Obtaining Buoy Data by Email for the Model Accurac... (February 2020)
Viewing NetCDF Weather Files in Panoply (January 2020)
Estimating Net Current Drift on a Long Ocean Passage (January 2020)
Progress to Weather (January 2020)
Plotting Text or Voice Weather Reports (December 2019)
Hurricane Eye Size (September 2019)
Frequency of ASCAT Data at a Specific Position (September 2019)
BuoyCAMs and Hurricanes, Part 2. (September 2019)
Inverse Barometer Effect in Puget Sound (August 2019)
Exciting New Barometer for Navigators (August 2019)
FTPmail No Longer Includes Observations—Plus Alter... (July 2019)
How to Obtain Custom GRIB Files (June 2019)
Another Interactive Test of the Oceanic National B... (June 2019)
FV3-GFS v. GFS—A comparison of real forecasts (June 2019)
Tools for Crucial Weather Routing: With an ongoing... (May 2019)
Compare ASCAT and WindSAT Scatterometer Wind Data (May 2019)
New PDF Edition of a Classic NWS Pub... (April 2019)
Moving Files Around on an iPhone and iPad (February 2019)
How to Wirelessly Transfer Files Among Computers a... (February 2019)
Tracking Jacob Adoram: An Exercise in Wind, Waves,... (January 2019)
Equatorial Countercurrents (January 2019)
Southern Hemisphere Weather Maps by Email (January 2019)
Florida Gulf Stream: An Exercise in Sources (January 2019)
Navigation Exercise: Crossing Currents (January 2019)
Squall Forecasting in Puget Sound... Maybe. (December 2018)
Satellite Cloud Images — Underway Sources (December 2018)
Marine Weather Workhorses... and Secret Sources (October 2018)
Barometer Use at Higher Elevations (September 2018)
Using Buoy Data and BuoyCAMs to Study Passing Stor... (September 2018)
Vessel Icing: Resources and References (September 2018)
Near-live Ship Reports by Email (August 2018)
Free Barometer App Designed for Mariners (June 2018)
Hurricanes on the Route to Hawaii — Weather vs. Climate (May 2018)
Effect of Leeway on Knotmeter Speed (April 18, 2018)
OpenCPN, Quick Start, One Chart (April 15, 2018)
Introduction to Charts in OpenCPN (April 15, 2018)
Sadler Tropical Atlases (January 2018)
Decision Making in Weather Routing (January 1, 2018)
MSLP vs. MSLP (November 2017)
Global Warming and Tropical Cyclone Statistics (November 2017)
100-foot Waves Expected near Aleutian Islands (October 2017)
Getting Archived NDFD Data (September 2017)
Wind Speed from Beaufort Force Number (August 2017) 
BC Canada Marine Weather Guide Back in Circulation... (August 2017) 
Comparing RTOFS and NCOM Model Forecasts to HF Rad... (August 2017)
Fog and Smoke Epilogue... the next day (August 2017)
Local Weather Office Forecasts Smoke, but not Fog! (August 2017)
Forecasting Local Winds with Meteograms (August 2017) 
How to Add a Draw Style to LuckGrib (August 2017) 
How to Combine Grib Files (August 2017) 
Zone Forecasts by Email (July 2017)
NDFD: Oceanic, CONUS, and Regional (May 2017)
International List of Weather Services (April 2017)
Buys Ballot Law to find wind direction from isobar... (January 2017)
Short Survey of Ocean Waves (January 2017)
Short Survey of Ocean Currents (January 2017)
Short Survey of Marine Weather (January 2017)
Wonderful Website on Barometers (December 2016)
GRIB Formatted Regional Wind Forecasts – Review an... (December 2016)
Wed Oct 12, 2016: Time to Start Your Barometer Cal... (October 2016)
Tropical Storm and Hurricane Advisories using FTPm... (July 2016)
Tropical Cyclone Advisories by Email Request (July 2016)
Wind Model Comparisons for Start of Pacific Cup (July 2016)
Vic-Maui Race Day 1, 2, (3) Winds (July 2016)
Inside Passage and R2AK Weather (June 3, 2016)
An Overview of Ocean Weather (May 18, 2016)
Great Lakes Wind Forecasts from HRRR (February 21, 2016)
Sailboat Racing on the Salish Sea—Part 1. Northern Waters (February 17, 2016)
Converting Weather Maps to BSB echarts (January 30, 2016)
Weather Maps—Where To Get Them and What We Get? (January 26, 2016)
Weather Maps to eCharts—Making the Header File (January 23, 2016)
How to load NOAA Weather Maps into OpenCPN (January 21, 2016)
How to Check the Accuracy of Airport Weather Reports (January 8, 2016)
How to Find Archived Weather Maps (December 19, 2015)
First pass at cell phone barometer calibration. (November 19, 2015)
Precision Barometers on Inland Commercial Vessels by Robert Reeder (November 6, 2015)
Weather Routing Options for Seattle to Victoria by Robert Reeder (November 6, 2015)
Personal Beaufort Scale (October 10, 2015)
Using a Portable Barometer to Set Ship's Barometer to SLP (October 8, 2015)
Manual of Barometry (WBAN) Now Online (September 29, 2015)
Grib Viewers — New Developments and Special Features (September 26, 2015)
Sides of a Tropical Cyclone, Part 2 Meteograms. (August 31, 2015)
Mariner’s Weather Checklist Before Departure (August 17, 2015)
High Seas Forecasts and Tropical Cyclone Alerts by Email Request (August 13, 2015)
Sides of a Tropical Storm (August 13, 2015)
New GRIB Viewer for Macs (August 2, 2015)
Direction of the Winds Aloft from Mare’s Tails — Time to Practice What we Preach (July 3, 2015)
Atlantic and Pacific Weather Briefings (June 19, 2015)
The National Digital Forecast Database (May 26, 2015)
Transpac Weather and Tactics by Stan Honey (May 17, 2015)
Weather Models for Transpac Sailors by Angeline Pendergrass (May 4, 2015)
TransPac Live Weather Resources (April 10, 2015)
Marine Weather Services Chart — How to Make Your Own. (March 19, 2015)
Reading and writing on weather maps (February 22, 2015)
Sydney-Hobart Climatic Winds (December 10, 2014)
Scatterometer Winds (December 2, 2014)
Taylor 1328PJ Sling Psychrometer — a Review (November 30, 2014)
Barometer for Wind Warning (November 7, 2014)
Barometric Pressure During Squall Passage (September 3, 2014)
Wind Near Clouds (March 5, 2014)
Model Predictions of World Winds (December 21, 2013)
Starpath Ship Reports Revised (December 17, 2013)
Local Pressure as a Squall Goes By (December 16, 2013)
Air Temperature Dependence of Sea Level Pressure Conversions (October 11, 2013)
"Point Four Four per Floor" –– QFE to QNH to QFF (August 3, 2013)
Mean Sea Level, Tides, and Barometers (July 29, 2013)
How to spell FitzRoy... or is it Fitzroy? (June 11, 2013)
Weather by Satellite Phone (May 5, 2013)
True Wind from Apparent Wind –– Revisited. (April 21, 2013)
Modern Barometry and its Important Role in Marine Navigation (April 19, 2013)
North Pacific Wind Statistics (April 16, 2013)
Revisiting the Secret Sources (April 14, 2013)
Weather Information for Voyages in the Australian Region by Kenn Batt, BOM (April 7, 2013)
New way to look at ASCAT data (April 4, 2013)
A Comparison of Ocean Current Models (March 22, 2013)
Final Word on Relative Humidity and Dew Point (February 23, 2013)
A Real OMG Omega Block over the E. Pacific (January 12, 2013)
It is Raining – What does that mean? Part 3 (January 3, 2013)
It's Raining, What Does That Mean – Part 2 (December 25, 2012)
First Pressure Check on Lacrosse C86234 (December 25, 2012)
Tactical Use of Scatterometer Data (December 6, 2012)
Track of HMS Bounty and the NHC Forecasts (November 2, 2012)
Gill Pressure Ports (October 21, 2012)
Dew Point and Temperature vs altitude (September 25, 2012)
Relative Humidity and Dew Point as a Function of Altitude -- A Way to Estimate Cloud Ceilings (September 25, 2012)
The Buys Ballot Law (July 31, 2012)
Predicting ASCAT Satellite Pass Times (July 23, 2012)
Timekeeping in Navigation and Weather (July 21, 2012)
Bermuda Race Satellite Winds (June 13, 2012)
A Nice Thermometer Dial—tiptoeing onto the metric scale (May 31, 2012)
How to overlay ASCAT Winds and Weather Maps on Google Earth (May 28, 2012)
ASCAT Notes and References (May 26, 2012)
It's Raining… What does that mean? (May 22, 2012)
How to learn the present winds offshore — West Coast of Vancouver Island, BC (April 19, 2012)
Str. of Georgia Wind Part 2 revised (April 5, 2012)
Southern Straits of Georgia Wind Forecast (April 4, 2012)


Choosing the Best Sextant Sights (April 2024)
Special Uses of the Star Finder and Sight Reductio... (March 2024)
How to Remember the Equation of Time (December 2023)
Measure the Eye Relief of a Sextant Scope (October 2023)
Ocean Position Plotting Sheets (May 2022)
Compare Pub 249 and Pub 229 Using the Celestial To... (January 2022)
Checking Sight Reduction With CelestialTools.exe (December 2020)
Accuracy of Backup Cel Nav using a Mark 3 Sextant (April 2020)
Stargazing for Mariners: Northern Sky (April 2020)
Finding UTC of LAN using an Analemma (January 2020)
The Regiment of the North Star (January 2020)
A Modern Regiment of the North Star (January 2020)
Options for Missing USNO Cel Nav Data (December 2019)
Who Is Ahead in an Ocean Race? (December 2019)
The 2020 Air Almanac (December 2019)
Navigator's Library for Extended Ocean Voyaging (November 2019)
Sextant Sight Planning with the Air Almanac's Sky ...  (November 2019)
Air Almanac Compared to Nautical Almanac (October 2019)
Great Circle Sailing with the 2102-D Star Finder (August 2019)
Expanding Scales on Universal Plotting Sheets (June 2019)
Finding UTC of LAN with the Starpath Custom Sun Al... (April 2019)
Star Names (February 2019)
Check Assumed Positions After Plotting Cel Nav Fix... (February 2019)
Does Accurate DR Matter in Cel Nav—Verb vs. Noun (February 2019)
Brightness of Stars and Planets (February 2019)
Fit-Slope Method to Analyze Sextant Sights (November 2018)
Solar Index Correction Method for Sextant Sights (September 2018)
Finding Longitude From the Time of Sunset (September 2018)
USCG Deck Exam Questions at (July 2018)
Note on USCG Exam Questions (July 2018)
Finding Watch Rate (July 2018)
Dip Short, Distance Off, and Running Fix (June 2018)
Davis Mark 3 Sextant Part 1 — How to read the Angl... (June 2018)
Ways to Get Accurate GMT (UTC) (May 2018)
Pub. 249 Vol. 1, USNO, and OpenCPN (December 2017)
Why the Book "Hawaii by Sextant" is Unique (December 2017)
Analysis of a Celestial Navigation Sight Session (October 2017)
Celestial Navigators: Save Your Eclipse Viewing Glasses (August 2017) 
Refraction in Celestial Navigation–still an issue,... (February 2017)
Most Likely Position from 3 LOPs (July 2016)
Is the Moon Waning or Waxing? (May 5, 2016)
USCG Chronometer Time — Bless Their Hearts (December 9, 2015)
Latitude by Meridian Transit, Ex-meridians, and the USCG Cel Nav Exam (November 29, 2015)
The Navigation Triangle (November 29, 2015)
Ways to Get Accurate GMT (UTC) (April 1, 2015)
Telling Time by the Stars (March 2, 2015)
Nuts and Bolts of Successful Ocean Navigation (February 22, 2015)
Finding Longitude by Lunar Distance using the Stark Tables (June 3, 2014)
Hawaii by Sextant — An Overview of Celestial Navigation (May 9, 2014)
Fit-Slope Method — A Shortcut to the Manual Solution from 1856 (April 25, 2014)
The Navigator's Sun (March 25, 2014)
Molasses – The Eatable Artificial Horizon (February 7, 2014)
The Celestial Sphere. May It Rest in Peace. (February 6, 2014)
Checking your Compass with the Sun (October 14, 2013)
Why Study Celestial Navigation in the Age of GPS? (October 3, 2013)
Navigation Calculators Online (September 4, 2013)
Finding Longitude from Sunset (April 27, 2013)
Finding the North Star (March 2, 2013)
UTC by Lunar Altitudes (Celestial Navigation) (January 20, 2013)
Great Circle Sailing by Sight Reduction (December 13, 2012)
The direction of sunrise and sunset—the old fashioned way (October 31, 2012)
Timekeeping in Navigation and Weather (July 21, 2012)
Refraction in a sink (May 21, 2012)

Electronic Chart Navigation

ECS Without GPS (May 2023)
Rock Symbols in ENC (February 2023)
Adding an image to a PDF (November 2022)
AIS in qtVlm (May 2022)
Role of SCAMIN on ENC (September 2021)
Online ENC Object Catalogs (September 2021)
MHW on ENC (August 2021)
MHW on ENC (August 2020)
Free eChart Viewers (July 2020)
"Swirls" — An Introduction to ENCs, and Why We Lik... (July 2020)
Introduction to NMEA 2000, with a refresher on NMEA 0183 (February 2020)
Who Is Ahead in an Ocean Race? (December 2019)
How to Make an RNC eChart From a Chart Image (December 2019)
Where to Get Nautical Charts (November 2019)
Assigning O-SENC Charts to a Dongle (August 2019)—Revolutionizing Nautical Chart Distri... (August 2019)
Best International Chart Deal Ever! (June 2019)
Moving Files Around on an iPhone and iPad (February 2019)
How to Wirelessly Transfer Files Among Computers a... (February 2019)
Chart Symbols: Rock or Coral on RNCs and ENCs (August 2018)
Paper Charts vs. Electronic Charts — Some Thoughts... (May 2018)
OpenCPN, Quick Start, One Chart (April 15, 2018)
Introduction to Charts in OpenCPN (April, 2018)
Minor Light Symbols on ENC in OpenCPN (September 2017)
Forecasting Local Winds with Meteograms (August 2017) 
How to Add a Draw Style to LuckGrib (August 2017) 
How to Combine Grib Files (August 2017) 
Simulate Instrument Data with OpenCPN's NMEA ... (August 2017)
Converting a Google Earth Path to a GPX Route (April 2017)
Rock Talk 2: RNC to ENC (November 2016)
Rock Talk — Is it all awash, or not? (November 2016)
History of Electronic Charting (November 2016)
How to Master Electronic Chart Navigation with the... (October 2016)
Network Connections to Navigation Software (October 2016)
Great App Idea from UKHO (October 2016)
How to Buy, Register, and Download Canadian Echarts (March 12, 2016)
Naming and Boundary Conventions on ENC eCharts (March 6, 2016)
The Strange World of Electronic Chart Boundaries (February 26, 2016)
Viewing and Downloading Nautical Chart with Google Earth (December 14, 2015)
Commercial Echart Ad is Food for Thought (August 26, 2015)
Don't Blame eCharts for Anything (December 8, 2014)
ECS Without GPS (January 20, 2014)
Free or Demo eChart Viewers (September 1, 2013)
Canadian eCharts for Electronic Chart Systems (August 4, 2012)


Slow Water Rule (November 2022)
Danger Bearings (April 2022)
Where to Get Nautical Charts (November 2019)
How to Fold a Chart (March 2019)
Countercurrent Crossing Nav Problem Solutions (January 2019)
Florida Gulf Stream: An Exercise in Sources (January 2019)
Navigation Exercise: Crossing Currents (January 2019)
Race to Alaska (R2AK) Navigation (June 2018)
Weems & Plath Expanding Square SAR Course Identifi... (June 2018)
Paper Charts vs. Electronic Charts — Some Thoughts... (May 2018)
OpenCPN, Quick Start, One Chart (April 15, 2018)
Introduction to Charts in OpenCPN (April, 2018)
Compass Bearing Fix — An Overview (November 2017)
UW Soundings Generator (August 2017)
Light Lists—A Modern Look (July 206)
Navigation Lights—The R2AK Short Course (July 2016)
Chart Plotting Tutorials (May 28, 2016)
Introduction to AIS (February 20, 2016)
Geographic Range — Time to Get Trivial (October 1, 2015)
Boxing the Compass (February 27, 2015)
Rotary Currents (September 1, 2014)
Piloting Practice with Geocaching — You Can Do It Online (March 24, 2014)
Google Earth as an Aid to Chart Reading (December 27, 2013)
Print-on-Demand Charts and pdf Charts (October 26, 2013)
Checking your Compass with the Sun (October 14, 2013)
Tides in Puget Sound (August 8, 2013)
How to Plot with Triangles (April 25, 2013)
Small Craft Wave Danger as a Function of Wave Steepness (April 9, 2013)
High Definition (HD) and Broadband Radar by Larry Brandt (April 8, 2013)
How to make current stations into waypoints in a batch process (April 6, 2012)
Natural Ranges—How accurate are they? (April 4, 2012)
GPS Accuracy in Tight Quarters (April 12, 2012)
Route Planning and Sharing with gpx Files (March 31, 2012)

Nav Rules
Introduction to Vessel Running Lights (Navigation ... (June 2020)
Social Distancing and the Navigation Rules (April 2020)
USCG Deck Exam Questions at (July 2018)
Note on USCG Exam Questions (July 2018)
Showing the Right Day Shape (August 2017)
Can exceptional behavior be considered ordinary? (June 13, 2016)
Right of Way in the Traffic Lanes (March 14, 2016)
Quick Way to Know if you are in the Traffic Lanes (February 12, 2016)
The New Inland Navigation Rules (July 28, 2015)
Lobster foot. (July 29, 2014)

How to Delete Browser Cookies (May 2020)
Navigator's Library for Extended Ocean Voyaging (November 2019)
Lat-Lon from Street Address (July 2019)
Compact Day of the Year Calendar (May 2019)
USCG Deck Exam Questions at (July 2018)
Note on USCG Exam Questions (July 2018)
Christopher Columbus and the Spherical Earth (May 2018)
Ocean Rowboat Polar Diagram (May 2018)
Effect of Leeway on Knotmeter Speed (April 18, 2018)
Shortcut to NGA Publications (January 2018)
Magnetic Dip and Zone Balancing (October 2017)
Viewing Eclipse by Boat May Bring Surprises (August 2017)
UW Soundings Generator (August 2017)
Adobe Digital Editions (ADE) User's Guide (March 2017)
NPR lets slip poor reporting of the El Faro case s... (December 2016)
Network Connections to Navigation Software (October 2016)
Using Polarized Sun Glasses as a Viking Sunstone (July 2016)
How to Verify Computer File Integrity (January 30, 2016)
AP Release on Tragic Loss of El Faro is Misleading. (October 5, 2015)
Ways to Get Accurate GMT (UTC) (April 1, 2015)
Telling Time by the Stars (March 2, 2015)
How a big, well-run, high-tech race boat, can go aground... almost (December 4, 2014)
Tricky Terms in Navigation (May 20, 2014)
Worldwide Shipping Lanes (December 6, 2013)
One Rombe Wrong, and What Do You Get? (November 22, 2013)
Notes on Loran (November 10, 2013)
Open Letter to the America's Cup Rules Committee (August 27, 2013)
Answers to Geocaching Exercise (July 14, 2013)
New Starpath Kindle and iBooks now online (July 3, 2013)
Ebooks Onboard (June 8, 2013)
A Few Nuts and Bolts of Iridium SatPhone Usage (May 4, 2013)
Two New Books from Starpath (April 2, 2013)
Course Boxes - Still Valuable in Modern Sailing (March 12, 2013)
More mainstream media on Viking sunstones (March 7, 2013)
Obtaining Ocean Current Data Underway (February 10, 2013)
State of the Art Ocean Current Presentation (January 31, 2013)
Atlantic Ocean Current Data and 6-day Forecasts (January 12, 2013)
Ocean Currents (January 8, 2013)
A Local Mini Surge (December 17, 2012)
NOAA Chief Misspeaks on Sandy Surge (December 14, 2012)
OPC maps for Google Earth (November 2, 2012)
Leif Karlsen's work on Viking Sunstones (August 23, 2012)
How to Print a Degree Symbol (June 11, 2012)
Robin Hood Complex in Book Publishing (March 22, 2012)


Anonymous said...

For every mariner, amateur and professional alike, this is a valuable resource. Many thanks for gathering and presenting and making it all available for ex- sailors like me. Well done!

abaig said...

I am a layman. Regarding Celestial Navigation, i want to ask that if the 'knowledge of celestial navigation' is specific to oceans only or is it applicable to desert navigation as well? Or there are different methods and procedures regarding desert navigation? Kindly address my confusion. I'll be grateful.

David Burch said...

Yes, this works well in the desert... and indeed in the jungle. Stanley used it to find Livingston, for example. But you need a view of a good horizon often available in some deserts or use an artificial horizon. I think we have an article on that in this blog, but we certainly cover the use of cel nav on land in our text Celestial Navigation textbook There are also bubble horizons that will do the job on land, but they are expensive. Occasionally you see WWII aircraft bubble sextants for sale at ebay that work as is or can be made to work. Generally not as accurate as a marine sextant.

Keith Fawcett said...


Please contact me. I am working on an article on Arctic Weather and the peril to marine transportation.


Keith Fawcett

David Burch said...

You can reach Starpath at