Expedition Navigation Software 
1 of 1- Roma
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Offline - Registered: 8/02/2024
- Posts: 3
Tidetech time is early by 1 hour in Expedition
I used Expedition with Tidetech a few times for Narrangasett, RI, USA and I noticed a strange thing:
1. time of current predictions displayed in Expedition are 1 hour earlier then same predictions displayed on Tidetech website. I checked that with slack time for the tidal current.
2. I compared the time of slack with tidal predictions from CMap and CMap is 1 hour later then Tidetech in Expedition.
3. Observations confirmed that the slack was 1 hour later than displayed by Tidetech in Expedition (thus confirming the time in CMap and Tidetech website was correct)
3. The PC with Expedition works in UTC-4 with daylight saving enabled mode.
I'm curious if anybody had a similar experience? is it something wrong with my settings or possibly a bug in software? if so, which one - Expedition or Tidetech API?
- Nick
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- Registered: 9/16/2015
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Re: Tidetech time is early by 1 hour in Expedition
Exp just uses the times in the Tidetech grib file, so, if there is an error, it will be in the model or grib file creation.
I think this has been seen before with Tidetech data.
The C-Map arrows are probably the same as the NOAA tidal currents in Exp.
Have you seen The Current Lab? Link on the Exp weather web page.
- Roma
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- Registered: 8/02/2024
- Posts: 3
Re: Tidetech time is early by 1 hour in Expedition
Thank you, Nick. I will check out the Current Lab. Is there a way to download their grib files in an easy way as with Tidetech and other weather data?
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Thread Starter- Nick
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Re: Tidetech time is early by 1 hour in Expedition
You have to get it from their web site, but it is probably the go-to model for for your site.
I don't know why OFS doesn't have models for LIS and Rhode Island.