SpotWx News

December 27, 2023
More new weather elements

Addition #1: The GFS now has individual cloud charts for low, middle, and high clouds. Cloud ceiling and visibility was also added.

Addition #2: Cloud ceiling was added to the HRRR and RAP models. The cloud graph was also modified to fix the misleading/inverse lines that previously occurred when either the base or top values were missing.

Addition #3: The 2.5 km HRDPS now has the Ventilation Index in the Planetary Boundary Layer graph.

Cloud Ceilling is the lowest level of broken cloud (at least 60% sky coverage). (The model data sometimes shows a ceiling at levels lower than a total 60% cloud coverage. It is not yet known why the NCEP does this.)

November 21, 2023
Addition of new weather elements

Addition #1: The Wet Bulb temperature has recently been added to most numerical weather models, with the current exeption of the GEPS and SREF. It's on the temperature graph, disabled in the legend by default. Wet Bulb temperature is not provided in the source data, so it's being calculated by SpotWx.

Addition #2: The GEPS graphs now have the control member for each element, plus there are new graphs for Total Rain, Total Snow, Total Freezing Rain, and Total Ice Pellets. Enjoy!

(FYI Given the renewed controversies at X (formerly known as Twitter), this news will not be posted there. Interesting times.)

April 23, 2023
Announcement on Accouncements

For several years SpotWx used Twitter and Facebook to distribute news, removing the link to this news page.

Use of those platforms dropped off in 2022, including deleting the SpotWx twitter account, in favour of simply posting banner messages on the home SpotWx page. However is it recognized that many weather followers use social media, especially twitter, so the SpotWx twitter account has been reborn as of today. Accouncements will still be posted to a banner on the main page as well.

This News page will be resevered to accounce major changes to SpotWx such as the addition of a new weather model or features, not temporary technical issues.

Thanks for using SpotWx!

March 8, 2017
RDPS data temporal frequency is now hourly!

Environment and Climate Change Canada updated the RDPS data temporal frequency from 3 hrs to 1 hr, available on SpotWx.

Nov 29, 2015
Unit customization added.

You can now customize your units on SpotWx, either on the top right options on the main page, or top right above the forecast graphs. (The tabular data charts are still in metric for the time being).

Oct 15, 2015
Low Level Wind graph added to HRDPS

The Low Level Wind graph was added for the HRDPS model domains.

June 23, 2015
New Time Zone tool

A new tool was added to the home page top header last week, allowing you to manually set your time zone.

May 18, 2015
New home page!

The home page has been updated to be more responsive for desktop, tablet and mobile use. Functionality remains basically the same.

The new design will make future improvements easier, such as the ability to change units (coming soon hopefully).

Jan 18, 2015
GFS Parallel now in production, replacing the previous GFS.

The NCEP moved the new 0.25 degree GFS to production on Jan 14, at which time the 0.5 degree GFS version was replaced on SpotWx with the new one.

Another small change: the 850 mb temperature has been added as an optional column to the tabular forecast pages.

Jan 6, 2015
GFS Parallel added...

The GFS Parallel has been added on SpotWx, which is a parallel run of the GFS with an improved resolution (0.25 degrees instead of 0.5 degrees) and extended forecast period. SpotWx is currently showing up to forecast hour 240. The model data is also available at 12 hour increments for hours 252 to 384, however these were purposefully omitted for the sake of efficiency and the questionable utility of a 16 day deterministic forecast.

The GFS Parallel was added last evening on SpotWx in preparation for the upcoming inclusion of this model in the normal NCEP production runs on Jan 14.

Other improvements in the last week: The RDPS now has vertical profile graphs, some changes were made to the precipitation graph axes to improve the ease of interpretation, plus some other little improvements and fixes.

Dec 26, 2014
Vertical Profile graphs added for HRDPS (GEM-LAM).

All the HRDPS domains, except the Continental domain, now have the vertical profile graph option.

Dec 24, 2014
Added a sneak preview of vertical profile graphs.

The GDPS (GEM Global) model forecast page now has an 'Open Profile version' link above, which goes to a new vertical profile time series display. It shows various weather elements (more to come) as a 'heatmap' with the pressure level on the y-axis from 1015mb to 250mb, and the time on the x-axis.

This display will undergo a few changes, and more models will be added, but it's being provided now as a little Christmas present.

Merry Christmas and Happy Holidays!

Dec 18, 2014
Major move and upgrade! Making progress...

What's new?

  • SpotWx has moved to a professional data centre (still in Canada) for greater capacity and reliability.
  • All graphs have been updated to work on both desktop and mobile devices, using HTML5 and JavaScript.
  • The HRDPS (GEM LAM) options have been expanded to include the Arctic and Lancaster domains, and the new Prairie and Continental domains.
  • The American HRRR model has been added.
  • The are various additions to the displayed weather elements, such as low/middle/high clouds for the RAP model.
  • The GEPS (CMC Global Ensemble) graphs are changed to show the median, 25-75th percentile and the min/max values for easier interpretation.
  • The entire graphical forecast page can now be exported as an image.
  • The tabular data format now has precip type and individual totals for each precip type as optional elements.
  • Some models have a tabular option customized for the Prometheus fire growth modeling software, with more models being added.
  • All pages are now served over encrypted HTTPS for your privacy.
  • What's gone?

  • Unfortunately there are a few casualties of progress...temporarily. The old GEM Hybrid is gone (which showed the RDPS from hour 0-48, and the GDPS from hour 51-240). Likewise the hybrid options for the SCRIBE graphs are gone. Why? Future improvements will include the ability to compare models, allowing you to overlay these and other models on the same graph. It was just too much to tackle at this time with my do-it-yourself programming skills.

    What's yet to come in 2015?

  • As mentioned above, the ability to compare models on the same graph (yes, I've been saying that for a year or more, but it's closer), and comparing the forecast to actuals.
  • Vertical time-series weather profiles.
  • Selecting your time zone, and units, maybe even a French option.
  • More models, like the GFS Parallel (0.25 degree resolution), other NAM domains, etc., if the server can handle it.
  • Improvements to the main page design.
  • I've been running a basic data service API (in CSV format) at the request of a paying client. Solidifying and improving that service for additional users will be a priority in 2015. Contact me if you are interested.
  • ...more, weather maps? There's many more ideas...we'll see how much spare time 2015 brings.

  • Feb 9, 2014
    Tabular display added

    A tabular display option has been added to most numerical models (GEM LAM (HRDPS), GEM Regional (RDPS), GEM Global (GDPS), NAM, GFS and RAP). You'll find the option on the top-left above the charts. The page is still a beta version with more options yet to come, published early by user request. BONUS: It should work on all mobile devices (except for the data export options, which use Flash).

    Let me know if you have any problems.

    Jan 28, 2014
    More recent improvements

    #1. The 850 mb temperature was added to the GFS temperature graph.

    #2. The GEM LAM (HRDPS) forecast pages now have the model elevation and land proportion information at the bottom of the page.

    Dec 21, 2013
    Some recent improvements

    Some recent improvements:

    #1. An avalanche forecasting office requested upper winds to be added to the US models. So the NAM, GFS and RAP all now have 925, 850 and 700mb winds, which roughly corresponds to 2500ft, 5000ft, and 10000ft above sea level respectively.

    #2. A skier requested the freezing level on the NAM, so the 0C isotherm (dry bulb freezing level) has been added alongside the existing wet bulb freezing level.

    Other improvements are being developed as time & resources permit. The next addition should be a tabular/text data option.

    Merry Christmas, Happy New Year, Happy Hanukkah, Happy Holidays, etc, etc. to everyone.

    October 21, 2013
    Update on the future of SpotWx

    I was recently made aware that some of you haven't been reading the Twitter or Facebook updates, which is understandable as many (myself included) can't access those sites from work. So here's a little update on the future of SpotWx.

    SpotWx is now routinely accessed from Canada's largest public and private forecasting offices, the major media outlets, numerous federal and provincial government departments and crown corporations, universities, private meteoroligists, and a host of weather enthusiasts. To facilitate growing usage, the addition of new features, and to reduce the risk of outages from power or hardware failures, SpotWx will be moved to a professional dedicated server host this winter (likely before Christmas). A redundant site is also being developed on the Amazon Cloud, to be activated should the main site ever go down.

    For those who have requested additional features over the past several months, I apologize for not yet moving forward on most those requests. Research into better hosting solutions has taken more time than expected. Time has also been spent optimizing code to use less RAM, allowing for more affordable hosting options.

    Some of you have specifically requested access to the source numerical data. An HTTP POST service was created, returning the data in CSV format, to meet the automation requirements of some users. A simpler manual CSV access method is also being developed for others. If you are interested in a similar option, please contact me so future products can be developed with your needs in mind.

    Thanks for all of your support, emails, ideas and suggestions. Keep in touch.


    May 13, 2013
    GEM Global (GDPS) now uses the new 25km version.

    The CMC GEM Global model is now using the recently released 25km version, and extends out to 240 hours. It replaces the old 30 km version which covered North America, and the 0.6 degree version which covered the globe, both of which extended to 140 hours. Old links to previous version of the GDPS will automatically redirect to use the new model data.

    More information about the GDPS can be found here:

    April 27, 2013
    Hourly UV Index added, global coverage. Sneak preview of new charts.

    A new UV Index product has been added. It's produced once daily, based on the 12Z GFS run. The forecast has hourly increments, starting at hour 01 (1300Z) and extending out 120 hours. It's currently a separate option at the bottom of the Numerical Models list. For more information, consult

    You will notice the UV chart looks different (hopefully better). It's the first product on SpotWx using new HTML5 charting code, called Highcharts. As there's no Flash involved, they'll work on any mobile device. I also added a button allowing you to save the chart as a JPEG image. All SpotWx charts will be converted to this new HTML5 version within the coming months.

    March 25, 2013
    Environment Canada's Global Ensemble Prediction System (GEPS) data added.

    The CMC Global Ensemble forecast data (one half of the North American Ensemble Forecast System, NAEFS), is now available on SpotWx. The CMC Global control member is shown as a thick red line, while all 20 "perturbed" members are shown as thinner coloured lines. Click on a line to see which member it is. The Ensemble median/mean have purposely been omitted for now.

    The model resolution is 1 degree, there are two model runs daily (00Z and 12Z), and the forecast extends out 16 days (ensemble data is generally used for long-range forecasting, starting around days 4-6).

    Specific information on CMC's Ensemble can be found here:, and more generic info on ensemble forecasting can be found on Wikipedia.

    March 10, 2013
    Lake Huron and Arctic Ocean wave models added.

    The wave models for Lake Huron and the Arctic Ocean have both been added (Lake Huron domain map, Arctic Ocean domain map). Both models are updated 4x daily (00/06/12/18Z model runs). All of Environment Canada's wave models are now available on SpotWx.

    Refer to this site,, for more information on the wave models. I'll add more documentation under the FAQ as soon as able.

    March 8, 2013
    Lake Erie wave model added.

    Environment Canada's Wave Model for the Lake Erie domain has been added (coverage map). The model is updated 4x daily (00/06/12/18Z model runs). Most of Lake Erie is frozen at the moment, so forecasts won't exist for those areas.

    Refer to this site,, for more information on the wave models.

    March 7, 2013
    Lake Superior wave model added.

    Environment Canada's Wave Model for the Lake Superior domain has been added (coverage map). The model is updated 4x daily (00/06/12/18Z model runs).

    Refer to this site,, for more information on the wave models.

    February 23, 2013
    Lake Ontario wave model added.

    Environment Canada's Wave Model for the Lake Ontario domain has been added (coverage map). The model is updated 4x daily (00/06/12/18Z model runs).

    Refer to this site,, for more information on the wave models.

    February 15, 2013
    Gulf of St. Lawrence wave model added.

    Environment Canada's Gulf of St. Lawrence Wave Model has been added (coverage map). The model is updated 4x daily (00/06/12/18Z model runs), and has a spatial resolution of 0.05 degrees. It overlaps the North Atlantic domain around Nova Scotia and up to Newfoundland, so both wave models will be available in those areas. Refer to this site,, for more information on the model.

    February 13, 2013
    North Pacific Ocean wave model added.

    Environment Canada's North Pacific Wave Model has been added (coverage map). The model is updated 2x daily (00/12Z model runs), and has a spatial resolution of 0.5 degrees. Refer to this site,, for more information on the model.

    February 10, 2013
    North Atlantic Ocean wave model added.

    Environment Canada's Wave Model has been added for the North Atlantic domain (map). The model will appear if you select a location off-shore, showing in blue text under the Numerical Weather Models list. The model is updated 4x daily (00/06/12/18Z model runs), and has a spatial resolution of 0.15 degrees. Refer to this site,, for more information on the model.

    Other wave model domains will be added in the coming weeks.

    January 4, 2013
    Working on improvements to graphs, and more....

    I'm working on major modifications to all the graph products to work on any device, including iPads, iPhones, Blackberry and Android devices. Hopefully this will be completed before spring. Other improvements will include the ability to compare models on the same graphs, to view previous model runs, and compare the forecast against actuals from the nearest weather station(s).

    The addition of wave models will also be coming this month (waiting for something beyond my control), followed possibly by the DGEX (downscaled GFS to 12km resolution).

    November 24, 2012
    SpotWx running greener than ever.

    Okay, it wasn't all about being green, but the entire site is finally running from a single, extremely efficient server. The original Windows XP box has been retired.

    SpotWx now only uses about 85 watts under normal load, and about 110 watts while processing new model data (including network devices). No more than your typical incandescent bulb! Plus it's hosted in Manitoba which operates exclusively on hydro electric.

    Now that's green!

    November 10, 2012
    Snow Depth (cm) has been added to the NAM model graphs.

    Check out the last NAM graph for snow depth. It represents anticipated snow on ground. As most stations only report the observed value once per day (and locations in-between stations are interpolated), it's a best estimate based on the most recent reported snow depth, the forecast snow, and local conditions (accounts for melting, compaction, etc.).

    November 6, 2012
    The GEM Regional (RDPS) model now has an improved 10 km resolution.

    The GEM Regional (RDPS) model has been upgraded to use the recently released 10 km version, replacing the previous 15 km version. The model domain also extends further south than before, all the way into southern Cuba.

    Sept 13, 2012
    All Numerical Models now have individual totals for all precip types.

    The precipitation graphs for all numerical models now have individual totals for rain, snow, ice pellets and freezing rain. The hourly precip icon is determined by the majority type for the period.

    Sept 9, 2012
    All GEM models (Regional, Global and LAM) now have precip types.

    Four precipitation types are now being displayed on all GEM model graphs; rain, snow, ice pellets and freezing rain. They each have a separate cumulative total, while the hourly precip icon is based on the majority (mouse-over the icon to view individual precip totals in the case of mixed precip). GEM LAM model users - you may have to clear your browser cache before the precip graphs display properly.

    The precip graphs for the NAM and GFS models will also be modified in the near future.

    Sept 2, 2012
    Improvements made for registered users.

    SpotWx will now keep you logged in until you sign out (or delete your cookies).

    The Favorites page was improved, adding links to your Spot locations which take you to that Spot on the map with the forecast options already displayed in the table.

    August 21, 2012
    RAP model (13 km resolution) added.

    The RAP (Rapid Refresh Products) model has been added. It's an hourly model, with hourly increments going ahead 18 hours. The RAP is often used for forecasting severe weather, since it runs hourly allowing it to keep up with changing conditions.

    SpotWx is currently displaying the 13 km resolution version, which covers the US and much of Canada, however missing all of northern Canada and also Cape Breton and Newfoundland (see the solid line on this domain map). However, a coarser 32 km version is also available covering all of North America, and will be added to SpotWx sometime in the future.

    August 12, 2012
    Extended-range Meteocode added.

    The extended-range Meteocode forecast data has been added to SpotWx.

    August 1, 2012
    Short-term Meteocode added.

    The short term Meteocode forecast data has been added to SpotWx (finally!). Meteocode is the detailed hour-by-hour numeric version of Environment Canada's public text forecast. It's also known by some as the corrected/adjusted SCRIBE.

    Environment Canada derives the short term Meteocode for each region by taking the forecast data from one or more representative SCRIBE points with the region, and adjusting it based on expert opinion. The public text forecast products you typically read are automatically produced by a computer based on these numeric values. As such, certain forecast elements are fashioned to make the text read as desired (i.e. winds are unusually steady over many hours and only occur in increments of 5 or 10 km/h, or the probability of precipitation is high for many hours but there is no precipitation amount). So keep this in mind when comparing the Meteocode to other products.

    Is the Meteocode any 'better' than other products? That depends, and is a subject for a much longer discussion.

    The extended Meteocode will be also coming soon.

    June 23, 2012
    GEM LAM (HRDPS) added for West, East and Maritime domains.

    The GEM Local Area Model (LAM), aka the High Resolution Deterministic Prediction System (HRDPS) has been added for the West (much of BC and Alberta), East (much of Ontario and southern Quebec), and the Maritimes. The model is 2.5 km resolution, valid for a 24 hour period, updated once a day.

    More info will be added regarding this model asap.

    June 14, 2012
    Vertical Velocity and Absolute Vorticity have been removed.

    OK, so they aren't too useful at the scale of a spot forecast, and people aren't used to looking at the actual numbers either.

    June 13, 2012
    Vertical Velocity and Absolute Vorticity added to the NAM model.

    Vertical Velocity and Absolute Vorticity at levels 850, 700, 500 and 250 mb have been added to the NAM model products.

    June 13, 2012
    Vertical Velocity and Absolute Vorticity added to all GEM models.

    Vertical Velocity and Absolute Vorticity at levels 850, 700, 500 and 250 mb have been added to all GEM numerical model products.

    June 7, 2012
    Canadian GEM Regional (RDPS) model now has 40, 80 and 120 meter AGL winds.

    The GEM Regional (RDPS) numerical model graphs now include winds at 40, 80, and 120 meters above ground level, which were recently made available by Environment Canada.

    June 7, 2012
    Canadian GEM (RDPS & GDPS) models available 30 minutes sooner.

    Processing of the Canadian GEM numerical model data has been moved to a new server, and is now available about 30 minutes earlier than before.

    May 6, 2012
    GFS model added.

    NOAA's GFS (Global Forecast System) model has been added. The resolution is 0.5 degrees, covering the globe. The model is updated every 6 hours, and has a 3 hour temporal resolution going out to 192 hours.

    April 23, 2012
    NAM precip graph upgraded.

    The NAM precipitation graph has been upgraded to indicate the type of precipitation, including rain, showers, thundershowers, snow, snow showers, freezing rain, and ice pellets. The accumulation of solid and liquid precipitation are summed independently (liquid precipitation includes freezing rain and ice pellets, for the purpose of showing accumulation). All snow amounts are assumed to have a 10:1 snow to water volume (i.e. 1 mm of water equivalent is shown as 1 cm of snow).

    April 7, 2012
    NAM model added.

    The North American Mesoscale (NAM) model has been added to SpotWx. The resolution is 12 km, covering much of North America down into Mexico and up to around the 60th parallel. The forecasts are issued every 6 hours. The forecast extends to 84 hours, with a 1 hr resolution out to 36 hours, and a 3 hour resolution past 36 hours.

    Some further improvements will be made, specifically to the precipitation graph to indicate the type of precipitation. Further information about the NAM will be added to the FAQ page as soon as possible.

    March 2, 2012
    'Where am I?' button added.

    A new 'Where am I?' button has been added on the home page. If your browser supports HTML5, it uses your browser's geolocation service (after receiving your permission). If not, it uses a location service provided by MaxMind based on your IP address.

    The 'Where am I?' button is intended to make SpotWx easier to use. Your location is not being tracked.

    March 2, 2012
    SCRIBE thickness graph added.

    A new thickness graph has been added to the SCRIBE forecast. It includes the 1000-500 mb (same as hPa), 1000-850 mb, and 850-700 mb thickness in decameters (dam). The data is used by forecasters to help determine temperature trends and the phase of precipitation.

    February 26, 2012
    New eta level 0.97 (approx. 1000 ft AGL) SCRIBE Temperature & Dewpoint graphs.

    A new SCRIBE graph has been added showing the eta level 0.97 data (which is approx. 1000 feet above ground) for temperature and dewpoint.

    The data is useful for evaluating low level cloud, inversions, fog, etc.

    February 26, 2012
    1000-500 mb thickness added to the SCRIBE Temperature graphs.

    The SCRIBE temperature graphs now have a line for 1000-500 mb thickness (units are in decameters, symbol dam). It is turned off by default (turn it on by clicking on the appropriate box in the legend).

    The 1000-500 mb thickness is a proxy for the 'bulk' airmass mean temperature, and is a very good indicator of the general temperature trend. Thicker/higher values (thicker atmosphere) indicate higher temperatures, and thinner/lower values indicate lower temperatures.

    Here is a detailed discussion of thickness values.

    *If you can't see the legend entry, your screen size is too small. Try zooming in on your browser window (ctrl++) to temporarily see the entry. This has been identified as a bug and will be fixed before summer 2012.