Friday, April 16, 2021

Re: {Tidal Potomac Fly Rodders} I don't know much about tides...

It is the larger bodies of water, i.e. the Chesapeake Bay and ultimately the Atlantic Ocean, that are driving the tides in our rivers. The water wants to be at the same level in all connected bodies, so as the tide pulls water from the Chesapeake to the Atlantic, the water levels in the Chesapeake drop and the local tidal rivers also drop to meet the equilibrium. The effects aren't immediate, so it takes time for the water to move.

There are other factors at play that I don't understand or remember from Oceanography 101 nearly 15 years ago, but I think the primary driver in the difference of those tidal times is the distance from those places to the Chesapeake Bay and the inlet to the Atlantic.

There are also other factors not included in those tide charts, primarily the wind, that will effect the tides too. For instance, a shift from an West to East wind can lower levels in the Chesapeake and affect the tides in the Potomac but the chart is just based on Sun/Moon.

Dalton
On Thursday, April 15, 2021 at 5:13:08 PM UTC-4 brian....@gmail.com wrote:
This was probably obvious to most, but it took me a few years to figure out that at Fletchers, a high and incoming tide makes for a more gentle river, and a lower outgoing tide means faster flow.  

My mind kept connecting with higher tide = more water = faster river...but of course, the tide and the river are separate things at Fletchers.  The incoming high tide meets the outgoing river flow and they mix together and the opposing forces calm things down - which is why you can sometimes float up river when the tide is high.  During a low/outgoing tide, everything is flowing the same direction - towards the bay - so the river at low tide can be very fast and hard to paddle upstream.

On Thu, Apr 15, 2021 at 1:51 PM Kevin Brugman <klb...@gmail.com> wrote:
I find it interesting to compare Tidal charts.  Following are 3 different sites for the Potomac in Washington DC and the Rappahannock in Fredericksburg.  All for morning High tide on 15 April

Tideschart.com
Washington DC - 10:57am
Fredericksburg VA -11:45am

Tide-Forcast.com
Washington DC - 11:22am
Fredericksburg VA -10:09am

Tideanddate.com
Washington DC - 11:00am
Fredericksburg VA -10:24am

Granted, these were slightly different locations, for example in DC one was Fletchers Boathouse, one was in Arlington and the other at Key Bridge.  I double checked the times, dates and locations for all three sites. 

I was surprised to see the large fluctuations as well as the difference in time between the Potomac and the Rappahannock.  I would have thought that they would have been closer.

Kevin

On 4/15/2021 12:45 PM, namfos wrote:
This site might help out when it counts when fishing...anywhere. 

This one's for Fletchers:

Mark
--
http://www.tpfr.org
---
You received this message because you are subscribed to the Google Groups "Tidal Potomac Fly Rodders" group.
To unsubscribe from this group and stop receiving emails from it, send an email to tidal-potomac-fly-...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/tidal-potomac-fly-rodders/6c8e27cf-7c98-4cbd-94aa-13842c91998en%40googlegroups.com.


--
http://www.tpfr.org
---
You received this message because you are subscribed to the Google Groups "Tidal Potomac Fly Rodders" group.
To unsubscribe from this group and stop receiving emails from it, send an email to tidal-potomac-fly-...@googlegroups.com.

--
http://www.tpfr.org
---
You received this message because you are subscribed to the Google Groups "Tidal Potomac Fly Rodders" group.
To unsubscribe from this group and stop receiving emails from it, send an email to tidal-potomac-fly-rodders+unsubscribe@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/tidal-potomac-fly-rodders/d87b3ada-dc9a-43cc-aab4-57aae67587b5n%40googlegroups.com.

No comments:

Post a Comment