The Sonrisa Net is a friendly and relaxed HAM net that meets daily on 3968khz LSB at 13:30z to support cruisers in the Sea of Cortez and Pacific Mexico. For many years Geary Ritchie, WB6PKH, would wake up every morning at 4am to collect data and prepare a daily weather report. He would then deliver his report at 15 minutes ’til the hour to boaters and land-based stations up and down the Sea. He also founded the sonrisanet.org web site to help deliver his information.

Sadly, Geary is no longer with us. The new sonrisanet.org is a small attempt to fill the gap. No, I’m not going to wake up every morning at 4am to collect data. The goal is to create a tool to automatically collect weather data relevant to sailors in the area and present it in a format that is easy for the net controller to read over the air.

The secondary goal, fortunately highly compatible with the first, is to make this information available to low bandwidth connections, such as WinLink or SailMail over the HF airwaves, or satellite internet connections. We plan to make the data available through Saildocs or something like it in the near future. There are plenty of graphical sites available to those with solid internet connections, and we have no intention to duplicate that, although we may provide convenient links.

Basically, we download GRIB-like data files from various weather models for the area we cover, extract information for spots of interest, summarize it by day, and present it.

To accomplish this, we download the GRIB-like files for the Global Forecast System (GFS) for primary wind forecasts, the North American Mesoscale Model (NAM) for short term high resolution wind forecasts, and the WAVEWATCH III for sea state forecasts, at regular intervals. While we aim to have the most current model run available, we are unsure of the exact time new data becomes available. The GFS model, for example, runs 4 times a day, or every 6 hours, at 0z 6z 12z 18z. Those are the times that they collect all the initialization data and begin the model run. But it takes several hours to run the program and then distribute the output to the servers, so currently we cheat a little and download new data for all three models every 3 hours. The models contain a parameter labeled “Forecast Reference Time” which we believe is the time of the initial conditions. We publish this time from the GFS at the top of the spot forecast table, along with a calculation of its age. Since it can take up to six hours to run the model and publish the results, the age may exceed six hours.

We take the wind data from the GFS and compute the mean wind speed and direction for each day, splitting the days at midnight local time. Since the GFS provides values every three hours, we have eight values in the average. There may be a more statistically appropriate method to summarize the values, such as median or some weighted average. In the future we hope to use the data from the NAM for the first 2 days and compute the averages over both day and night, probably splitting at 7am and 7pm local time. The NAM data is currently used for the hourly wind graph.

Determining the average wind speed and direction poses an intriguing challenge. Unlike other quantities, wind direction cannot be averaged by simply adding and dividing, as it is a 360° circle. To illustrate, consider the wind blowing at a consistent speed from 350° for half of the day and from 10° for the other half. While many might assume the average wind direction to be from the north (0°), the arithmetic mean is actually 180° (south). This issue is resolved by averaging the north/south vector and the east/west vector separately, and then combining them to produce a speed and direction. This also gives greater weight to the directions with the stronger winds. However, there are cases where this method fails. For instance, winds blowing at 10kts from the east for half of the day and from the west for the other half would result in a vector average of wind speed 0kts, with an undefined direction. In this situation, people would typically consider the average wind speed to be 10kts. Consequently, we determine the wind speed by averaging only the magnitudes and the wind direction by averaging the vectors.

The GFS and NAM models provide a wind gust parameter. Sailors are usually concerned with extreme conditions, so we report the maximum gust value expected over the period. Therefore, it is safe to assume that the maximum gust will be near the highest wind speed expected for the day. If the average wind speed is close to the maximum gust value, then it is likely that the wind will be blowing consistently throughout the day. However, if there is a greater spread between the average and maximum gust, it is safer to assume that there will be lighter winds for part of the day.

The sea state, obtained from the WW3 model, is treated similarly. The primary wave direction is determined by vector averaging, like the wind. Since wave height typically does not vary significantly within a day, we report the only minimum and maximum values of the significant height of combined wind waves and swell. However, if the difference between the minimum and maximum values is less than 1 foot, we report only one value. Typically, the wave period varies by only a few seconds unless the sea state changes from a long to a short period, or vice versa. Therefore, we report the mean of the primary wave period. If the difference between the minimum and maximum wave periods is greater than 4 seconds, we report the actual range.

We have not yet optimized our code for speed, so response times may be slow, especially if requesting everything everywhere all at once. We hope to pre-process or cache some of this data to improve speed in the future. Maybe we need to hire more programmers.

Overall, we hope this explanation helps you understand the presented data, its usefulness, and limitations. Following is an incomplete list of things we hope to improve, in no particular order.

• Determine or find a test for when fresh model data becomes available, so that the most current data can be presented.
• Use the NAM data for the first 2 days, and average over day and night, or maybe even morning, afternoon, and night.
• Investigate the usefulness of other models, such as the HRRR and NDFD, as compared to the NAM
• Determine the most appropriate method to aggregate the data, especially for wind speed, such as mean, median, weighted average, or other?
• Optimize the code for faster response times.
• Locate and fix potential bugs which might cause server errors if the data files do not contain expected parameters.

We value your feedback greatly! We know we can’t think of everything ourselves, so please don't hesitate to make suggestions. Whether you like or dislike something, or have ideas on what we can add, we want to hear from you. While we hope to add a comments section someday, for now, you can send an email to , or simply talk to N6OLY on the air.

If you have meteorology experience, we would greatly appreciate your expertise. We are open to suggestions on data sources and how to best summarize and present the data.

If you have web development or programming experience, we welcome your involvement! Feel free to get in touch with us to discuss how you can help.

And lastly, if you're feeling generous, you can always make a donation or buy us a beer. We do have costs involved in maintaining the server, and every little bit helps!

Our goal is to present weather forecast data from various sources in a way that is friendly to sailors and cruisers on the Pacific coast of Mexico.

However, please note that weather forecasts are inherently unreliable and can change rapidly. They should not be used as the sole source of information for making critical decisions, especially when safety is involved. Always exercise caution and consult multiple sources before making any decisions. In addition, the Sea of Cortez is known for its unique weather patterns, which can be affected by local land effects that are difficult to predict. Therefore, any forecast for this area should be considered with caution.

Furthermore, our website is an amateur, non-commercial project and is not designed by a meteorologist. While we strive to provide accurate and up-to-date information, we cannot guarantee its accuracy or reliability.

In short, please use the information on our website at your own risk. We are not liable for any damages or losses that may result from the use of our website or the information presented on it. For a better understanding of how we obtain and present the forecast data, see How does it work?

Remember, even the best meteorologists can't predict the weather with 100% accuracy. So if our website's forecast turns out to be a little off, just be glad that you’re not sailing in the Bermuda Triangle. Thank you for using our website, and happy sailing!