Fishing Anglers are known to watched barometric (atmosphere) pressures to help predict fish movement and feeding patterns for many years.
Two important things to note which can help you understand how oxygen levels impact the barometric levels and its relation to the fish’s behavior:
- High atmosphere pressure and water current forces more oxygen into the water. Fish are more likely to feed under these conditions.
- Fish are cold blooded species and are more likely to feast more in cold water than warm since cold water holds more oxygen than warm.
According to reference.com, normal barometric pressure is about 29.6 in-Hg. Historically, all-time low has reached 25.9 and all-time high of 32.01. Dramatic changes to barometric pressure correspond to extreme weather events.
Note: Barometric pressure is generally measured in inches of mercury (in-hg)
Falling Barometric pressure typically indicates a stormy weather and/or heat wave is coming.
Rising Barometric pressure typically indicates dry, colder weather.
While there are plenty to understand when discussing barometric pressure and its relation to fish behavior, there are 5 key times when barometric changes are important for fishing.
Note: the readings are subjective to your living vicinity will differ
In very cold water, fish digest food much slower and their enzymes are slower acting. This causes the fish to be less active but become more active as the water and oxygen levels are right. Low pressure means the water is a bit warmer with oxygen levels dropping making fish less active.
Low pressure readings can be around 29.7 to 30.4/Cloudy/Rainy weather.
Tip: There’s a phrase to remember which is “Low is slow” and fish tends to go deep into the water to conserve energy, so try casting out further and slow down and downsize the lures can increase your chance of success.
When barometric pressure is high, this is when the skies are clear allowing the sun and moon to illuminate the waters creating lots of underwater visibility. Fish are likely to find cover and move further away from the banks and into deeper parts of the water.
During high pressure, you can expect the water to be cooler than normal accompanied with higher level of oxygen. In this condition, it’s a bit too cold for any real feeding action.
High pressure readings are typically above 30.5+/Clear Skies.
Tip: Fish are likely to be congregated in the water columns during this time. Try to locate them and work with baiting technique such as vibrating ones to irritate them to strike.
Fish will feed more actively right as they sense the pressure will drop. This affects their feeding behavior. This is usually the case when weather conditions are getting worse, such as an incoming storm. Fish will prepare by feasting and this is the perfect time to go fishing.
Fish will react to rising barometer by being a bit more active. These are days where the weather conditions are improving from bad weather.
Fish will have return to their normal feeding activities and anglers will find other elements to assess to increase their chance of success such as moon phases or wind direction.
Stable pressure readings are typically 29.6 in-hg
My favorite time to fish based on the barometric pressure is when it’s moving. I have found falling barometric pressure tends to be favorable for fishing. Fish tends to be frantic and feed heavily right before the storm. Either way, the best time is to catch when the barometric pressure is either rising or falling.
For local water and barometric readings including tide levels and water temperature. I have found these sites helpful: