Weather at NSC – 24-hour History

Welcome to the NSC Weather Station page. The data displayed on this page is collected by the NSC-owned Davis Vantage Pro2 Weather Station, mounted on the lighthouse at the harbour entrance. Read the Usage Notes.

Alternative modal view of lighhouse: lighthouse

Usage Notes


All times are recorded in Universal Time Coordinates (UTC) and converted to your device local time for display.

All wind directions are relative to True North.

The wind, temperature, pressure and humidity charts were developed using the Highcharts library. Features of Highcharts include the ability to display conditions at any given time by hovering your cursor over a chart, and the ability to highlight or de-select certain properties by clicking on that property on a chart's legend. Highcharts is a commercially-available charting library available at no charge for not-for-profit organizations like NSC.

Wind Data Accuracy and Reliability

The Weather Station is mounted on the lighthouse at the harbour entrance. Winds from the northwest to the northeast (a 90° sector) reach the weather station unimpeded, providing reliable wind direction and strength readings. However, winds from the northeast to the northwest (a 270° sector in a clockwise direction) are obstructed by land, trees and buildings, and thus both the wind strength and direction are more variable than on the lake, and the wind strength will generally under-report the winds on the lake. The weather station does accurately report the winds at the station, but that may not be a reliable indication of the winds on Lac DeschĂȘnes.

Note: When no new data is available, either because the Weather Station is down, the communication link is inoperative or the WeatherLink Cloud storage is offline, the last available values are used, resulting in constant-value (straight-line) plots.

Weather Station Data

The NSC's weather station uploads its sendors' data every 5 minutes to the Davis Weatherlink Cloud Storage through a small device connected to the internet via the office router. Every 10 minutes starting on the hour, the NSC web server downloads the latest block of "current" data from the WeatherLink Network and stores the time, wind, temperature, humidity and pressure values in a running 24-hour file. It takes 10-15 seconds for the new data to be available on the NSC server. When you open or reload this page, the 24-hour file is downloaded by your web client and processed to generate the charts below. To update the charts, reload the page.

The wind speeds and directions plotted in 10-minute increments, use "last 10-minute average" values. The wind gust is the maximum wind speed over the same 10-minute period. Note that this is different from the 5-minute increment plots in the Current & 6-hour History page which use "last 2-minutes average" values. Therefore, the hourly values displayed in this page and the Current & 6-hour History page will differ.

The data on the Weatherlink Network is also available to other weather websites, including Sailflow, Weatherlink, Weather Underground and CWOP.

Wind Direction

The wind direction polar plot is also known as a Radar Plot; it shows the most recent wind direction at the outside of the polar plot, similar to the depiction of the original NSC "Windicator". When the wind drops below 1.0 knot, the direction is frozen until the wind increases above 1.0 knot.

Wind Frequency

The wind frequency polar plot is also known as a Wind Rose. The average wind data points are grouped by speed and direction according to one of 7 speed ranges and 16 compass (cardinal) points. Groups are plotted as color-coded sectors.

Wind: Prevailing & Gusts

This chart presents prevailing wind strength and direction (based on True North) on an X-Y scale. When the wind drops below1.0 knot, the directional arrow is replaced by a small dot. The vertical axis adjusts its scale automatically to accommodate the winds over the previous days.

Temperature, Pressure & Humidity

Self-explanatory, similar to the chart, "Wind: Prevailing & Gusts".


NSC does not warrant the quality, accuracy, or completeness of any data presented in this page. The following weather information is provided on an "AS IS" basis without warranty or condition of any nature.

Suggestions? Errors?

Please contact the Weather Station Team.

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Graphics data updated at . Refresh.
A Current and 6-Hour History and a 7-day History are also available.

....Loading the Weatherlink data file.

Visit the main Weather page.

Page updated on 2023-08-28. Plot scripts updated on 2022-08-10.
Questions or Comments? Please email Weather.
Find out who contributed to this project in Credits.

Credits ×

Several volunteers contributed to the NSC Weather Station Project:

Data Manipulation and Presentation

Daniel Servranckx designed the data acquisition, conversion and handling from the Davis Weatherlink Live repository, created this page layout and content, and coded the Highcharts scripts that generate the embedded chart displays.

Note: development on the previous RBR Weather Station display by Yaro Shkvorets was used as a reference for the current design.

Weather Station Acquisition, Installation and Testing

Marek Dziedzic conducted the overall requirements analysis, liaised with potential vendors, created the purchasing specification document, created the Davis WeatherLink Live account, configured the network interfaces, ran hardware acceptance tests, calibrated the wind sensor, participated in the station mount design and in the overall web layout and application testing.

Hugh Morrin initiated acquisition process with the Fleet Captain, assisted Marek with the specifications document and mounting design, liaised with the Canadian Coast Guard for the authorization to mount the station on the harbour entrance lighthouse, participated in the overall web layout and application testing, and coordinated the physical mounting on the lighthouse with Gene Bruce, the Marine & Property Manager.

Maintenance and Operations

All the above individuals remain involved in the maintenance and operations of the Weather Station and display applications.


The Davis Weather Station and a 3-year subscription to the Weatherlink Pro Cloud Storage were funded through the NSC Fleet Captain's budget.