Tide Calendar discrepencies

[rplarry]

Wondering if you guys can help me with a question I have had for a long time regarding the accuracy and discrepancies of various tide calendars.

I have noticed that depending on the tide chart/calendar, 2 different calendars can be off by and hour. My question is, how do we know which one is accurate?

For most, an hour is not that big of a deal. But, when fishing the tides from shore, and hour can make a huge difference. Especially when the tide swings are huge on a particular day.

So, here's me case in point. Here are two different tide calendars.

Low tide, on October 3rd, for this chart is at 4:47am.

http://predmar.cicese.mx/mensual/ptp/ptp1410.pdf


On this second chart, low tide on October 3rd is 3:43am

http://tbone.biol.sc.edu/tide/tideshow.cgi

And this one is different too, by not by a complete hour

http://www.tide-forecast.com/locations/Puerto-Penasco-Sonora-Mexico/tides/latest

Has anyone else ever questioned this ?

 

[Stuart]

Close, but no cigar? Yeah, they do vary a little bit. For the most part, I think it has to do with the location at which the calendar is predicting the tide. Some use general coordinates for an area that are probably not exactly where you're going to be fishing. Here's a helpful tip, though. Do you have a GPS? I have a couple - one on the boat and a handheld. They both have solar/lunar functions and tide predictions for the day. I've found those to be pretty darn accurate because it's basing the prediction on your current coordinates. For example, high tide at the 51 mile reef is obviously not the same time it is in Penasco or at San Felipe.

So, you can use the tide calendars for a general prediction (planning), then use your GPS for a specific prediction (execution). That's generally how I do it.

 

[rplarry]

Close, but no cigar? Yeah, they do vary a little bit. For the most part, I think it has to do with the location at which the calendar is predicting the tide. Some use general coordinates for an area that are probably not exactly where you're going to be fishing. Here's a helpful tip, though. Do you have a GPS? I have a couple - one on the boat and a handheld. They both have solar/lunar functions and tide predictions for the day. I've found those to be pretty darn accurate because it's basing the prediction on your current coordinates. For example, high tide at the 51 mile reef is obviously not the same time it is in Penasco or at San Felipe.

So, you can use the tide calendars for a general prediction (planning), then use your GPS for a specific prediction (execution). That's generally how I do it.

Makes sense Stuart. While my primary fishing in RP is limited to shore & kayak fishing, I still think I will pick up a GPS.

Thanks for the reply!

 

[Stuart]

They have really come down in price. You can't beat the Garmin handhelds. Make sure you get one that has basic marine features. I have an old one I'd give you, but the screen goes bonkers on it for no reason. Currently collecting dust.

 

[rplarry]

So Stuart, I'm sure you will get a kick out of this most scientific test of the different tide calendars.

Was down a week or so ago, and fished from shore, the Mirador, Las Conchas and a little in the estuary. The Mirador was most productive, although nothing to write home about. The bait in the water was so abundant that even casting into the middle of the MILLIONS of bait fish, rarely was there a hook-up. I truly think the fish and the birds were full to the gills.

But, on the hook-ups I did have, they were extremely strong strikes. After losing 2-3 fish, I finally landed what I thought was a big Corvina, but it turned out to be a moderate sized and hard fighting Sierra. Fought like crazy, especially on light gear.

So, for the tide experiment. For the brief time I was out at the estuary, I got out there at exactly "low tide". Low Tide per the Rocky Point Times tide calendar.

I put a shell in the water, right at water's edge. (this is the highly technical part of my scientific experiment). For the next hour, plus 10 minutes at LOW tide, the shell stood strong. The water's edge drifted DOWN about 3 inches, then about 50 minutes after RPT low tide chart, it started coming in.

So, either it takes a lot longer for the tide to begin its accent into the estuary than on the chart, or, this chart is an hour off like many of the discrepancies in different online tide charts ??

Who knows? Interesting though, because not exactly sure when the tide will start moving in for certain ?

 

[Stuart]

SCIENCE!!! Larry blinded me with SCIENCE!!!

Are you talking the annually published tide calendar with the pretty pictures and all? I usually buy one every year because as said earlier, it's great for planning purposes. Where they really estimate (the coordinates of) the tidal movement, well, I have no idea. But based on your scientifically sound experiment for where you fish, you now know you can sleep an hour later than what the calendar shows!