Swear By The Barometer?

[jkroosz]

Sidenote: On moonphase, the most important full moon is right before spawn. It signals the end of pre spawn for most fish, and your approach and techniques may need to change.

[Hattrick7]

Just asked this question in my mind today. There's been a high pressure system that's moved in for the past few days and I've noticed that the bite has slowed down considerably. I'm fishing the same lake, throwing the identical baits and noticed that it's slowed down. Also fished a new lake and the bite has slowed to a crawl when they were pretty active prior to the high pressure.

The winds have also really picked up. (15+ knot gusts). The winds are also coming out of the east and I read on this forum I think that when that happens it does have an effect on bites.

Not too big a deal since I'm just fishing to fish but it does cross my mind as to why the bite has really slowed down considering that I'm using the same rigs and actually more plastics to try and get a bite whereas prior to the high pressure just a couple plastics got the job done. I did use a couple new plastics and then start second guessing them and switched back to old trusties and nothing. So it's not the bait.

If barometric pressure does play a bigger role pretty intersting phenomenon.

[gobig]

I do not let the weather dictate if I go fishing. What weather/barometric pressure does is give me a starting point. Just like the seasons attract fish in to certain locations the weather will position them in the water column. Moon phase, current and water level fluctuation will also have an effect.

[Sam]

Not really.

 

I do watch the weather and cold fronts moving through the area plus if the wind is from the east.

 

Otherwise, it is on the water to try my luck.

[Nitrofreak]

If your worried about the barometric pressure when you fish , your fishing too shallow !!!

[KritterGitter]

If your worried about the barometric pressure when you fish , your fishing too shallow !!!

Agreed.... I watch the pressure quite regulary, and yes it has a huge affect in my area, the deepest pond is around 14-15' with most areas around 5-10'. I would have to say that the pressure affects the ponds around here more than most being so shallow and realatively still current.

[Catt]

Lake: Toledo Bend Reservoir

Seasonal pattern: Early Pre-Spawn

Weather:3 days before a front, overcast skies, falling barometer, southwest winds light & variable

Water: slightly stained mid 50s

Yea I be watching the barometer

[WRB]

Would you prefer fishing during overcast days with chance of light rain and mild wind conditions or bright sunny days with strong winds? If that doesn't matter to you than ignor the barometric pressure or weather conditions.

Standard barometric pressure @ sea level is 29.92 inches of mercury. Variances to standard pressure (14.7 psig) of 0.5 inHg is a big change, 1 point would severe weather changes, lower indicating storm conditions, higher indicating high winds not related to a hurricane. When watching a barometer for change you are looking for slight rise or fall, not big changes.

Tom

[RoLo]

Facts Require Confirmation....Beliefs Thrive Without Confirmation

Barometric pressure is not without merit but its relationship to fish behavior is widely misconceived.

The association between atmospheric pressure and fish disposition is coincidental, it is not causal.

Additionally, barometric pressure is a lagging indicator, like driving your car while looking in the rear-view mirror.

 

Water Pressure versus Air Pressure

Air is a highly 'compressible' medium, whereas water is virtually 'incompressible'. Changes in barometric pressure

are barely perceptible to fish. As an example of Air versus Water, imagine pressing an air-filled balloon

against a rock and expecting a reaction from the rock. To further display the power of water pressure,

allow me relate a graphic but real-world example. In saltwater, we often fished for ling (red hake) and whiting (silver hake)

at the Ambrose Lightship where water depths exceed 100 feet. Fish that were hauled topside were subjected to

a lethal plunge in water pressure. Due to a dramatic reduction in water pressure their eyes were bulging

out of their sockets and their gullet was in their mouth and turned inside-out.

Needless to say, catch-and-release was not an option.

 

A Little Science Goes A Long Way

All matter has weight, even gaseous matter such as the earth's atmosphere. Air is extremely light

but the earth's atmosphere is several hundred miles high, so at sea level our atmosphere exerts 14.7 pounds

of pressure per square inch. Barometric pressure (atmospheric pressure) is usually quantified by the height

that a column of mercury rises in a standardized tube. At sea level, normal barometric pressure will force mercury

29.92 inches up the tube, which is expressed as 29.92 inHg or 'one atmosphere'. Okay, now we have

a Barometric Baseline, so let's add some meteorological events. During an average cold-front

(high-pressure clockwise cell) the barometric pressure will climb to around 30.32 InHg, a mean rise of 1-1/3%

on balance. During an average warm-front (low-pressure counterclockwise cell) the barometric pressure

usually falls to around 29.52 inHg, a drop averaging 1-1/3% below normal.

 

In contrast to air, water has a far greater specific gravity. At a depth of 34 feet, water exerts the same

pressure per square inch (lb PSI) as several hundred miles of atmosphere. So at 34 ft deep, the sum

of air pressure and water pressure is 29.4 lb PSI or 'two atmospheres'. Due to water's high specific weight,

when a fish swims just 5.4 inches downward in the water column, the rise in pressure is identical to an average

high-pressure system (cold front). Inversely, when the same fish swims 5.4 inches higher in the water column,

the drop in pressure is equivalent to an average low-pressure cell (warm front). For anyone interested in calculating

their own formulas & results, I've included two useful constants:

=>  1-foot column of water = 0.433 lb / sq. in.

=>  1-foot cube of water = 62.35 lb 

 

COINCIDENTAL FACTORS

In and of itself, barometric pressure exerts no influence on fish behavior, however it frequently accompanies

meteorological conditions that do. In any case, there's no advantage to monitoring a proxy like atmospheric pressure,

when the direct causes are more obvious and more timely. Atmospheric pressure is not only a symptomatic indicator

but often a laggard indicator. Listed below are easily recognized weather conditions that directly affect the behavior

and disposition of fish, regardless of barometric pressure:

 

APPROACHING COLD FRONT

> Falling Barometer  

            Until the cold front is actually upon you, the barometer will likely continue to creep lower

> Building Cloud Cover

            Reduced light level is positive for fishing, with or without a falling barometer

> Increasing Winds

            Wind creates surface refraction that reduces luminosity and also aggregates plankton

            which are both positive conditions, with or without a falling barometer

> Steady Air Temperatures

            Stable weather over the long-term is very positive to fishing.

            but over the short-term, steady air temperatures have no appreciable effect

 

PASSING COLD FRONT

> Rising Barometer  

            By this time, increased winds & falling air temperatures have spilled the beans

> Clearing Cloud Cover

            Increased light levels are negative for fishing, with or without a rising barometer

> Gusty Winds

            Early on, gusty winds are not negative, but persistent cold northwest air mixed into the epilimnion

            eventually becomes negative. Barometric pressure offers no input as to the pivot point in timing. 

> Falling Air Temperatures

            Falling air temperatures is one of the most negative events in bass fishing,

            especially for Florida-strain bass. Once again, barometric pressure offers no useful input

==============================================================================================================

 

APPROACHING WARM FRONT

The four conditions noted above under 'Approaching Cold Front' also apply to an 'Approaching Warm Front'.

In other words, the barometer cannot differentiate between an approaching warm front and an approaching

cold front (ouch). On the other hand, 'wind direction' quickly and accurately distinguishes an approaching

warm-front from an approaching cold-front. 

 

Roger

[Catt]

Merci Beaucoup Roger!

[SirSnookalot]

If I waited for the perfect barometric pressure, I would have missed so many wonderful fish.  I do pay a lot of attention to certain weather factors, none of which keep me from fishing, but has bearing on target species and the areas I'm going to fish.

[Nitrofreak]

Facts Require Confirmation....But Beliefs Thrive Without Confirmation

Barometric pressure is not without merit but its relationship to fish behavior is widely misconceived.

The association between atmospheric pressure and fish disposition is coincidental, it is not causal.

Additionally, barometric pressure is a lagging indicator, like driving your car while looking in the rear-view mirror.

 

Water Pressure versus Air Pressure

Air is a highly 'compressible' medium, whereas water is virtually 'incompressible'. Changes in barometric pressure

are barely perceptible to fish. As an example of Air versus Water, imagine pressing an air-filled balloon

against a rock and expecting a reaction from the rock. To further display the power of water pressure,

allow me relate a graphic but real-world example. In saltwater, we often fished for ling (red hake) and whiting (silver hake)

at the Ambrose Lightship where water depths exceed 100 feet. Fish that were hauled topside were subjected to

a lethal plunge in water pressure. Due to a dramatic reduction in water pressure their eyes were bulging

out of their sockets and their gullet was in their mouth and turned inside-out.

Needless to say, catch-and-release was not an option.

 

A Little Science Goes A Long Way

All matter has weight, even gaseous matter such as the earth's atmosphere. Air is extremely light

but the earth's atmosphere is several hundred miles high, so at sea level our atmosphere exerts 14.7 pounds

of pressure per square inch. Barometric pressure (atmospheric pressure) is usually quantified by the height

that a column of mercury rises in a standardized tube. At sea level, normal barometric pressure will force mercury

29.92 inches up the tube, which is expressed as 29.92 inHg or 'one atmosphere'. Okay, now we have

a Barometric Baseline, so let's add some meteorological events. During an average cold-front

(high-pressure clockwise cell) the barometric pressure climbs to around 30.32 InHg, a mean rise of 1-1/3%

on balance. During an average warm-front (low-pressure counterclockwise cell) the barometric pressure

usually falls to around 29.52 inHg, a drop averaging 1-1/3% below normal.

 

In contrast to air, water has a far greater specific gravity. At a depth of 34 feet, water exerts the same

pressure per square inch (lb PSI) as several hundred miles of atmosphere. So at 34 ft deep, the sum

of air pressure and water pressure is 29.4 lb PSI or 'two atmospheres'. Due to water's high specific weight,

when a fish swims just 5.4 inches downward in the water column, the rise in pressure is identical to an average

high-pressure system (cold front). Inversely, when the same fish swims 5.4 inches higher in the water column,

the drop in pressure is equivalent to an average low-pressure cell (warm front). For anyone interested in calculating

their own formulas & results, I've included two useful constants:

=>  1-foot column of water = 0.433 lb / sq. in.

=>  1-foot cube of water = 62.35 lb 

 

COINCIDENTAL FACTORS

In and of itself, barometric pressure exerts no influence on fish behavior, however it frequently accompanies

meteorological conditions that do. In any case, there's no advantage to monitoring a proxy like atmospheric pressure,

when the direct causes are more obvious and more timely. Atmospheric pressure is not only a symptomatic indicator

but often a laggard indicator. Listed below are easily recognized weather conditions that directly affect the behavior

and disposition of fish, regardless of barometric pressure:

 

APPROACHING COLD FRONT

> Falling Barometer  

            Until the cold front is actually upon you, the barometer will likely continue to creep lower

> Building Cloud Cover

            Reduced light level is positive for fishing, with or without a falling barometer

> Increasing Winds

            Wind creates surface refraction that reduces luminosity and also aggregates plankton

            which are both positive conditions, with or without a falling barometer

> Steady Air Temperatures

            Stable weather over the long-term is very positive to fishing.

            but over the short-term, steady air temperatures have no appreciable effect

 

PASSING COLD FRONT

> Rising Barometer  

            By this time, increased winds & falling air temperatures have spilled the beans

> Clearing Cloud Cover

            Increased light levels are negative for fishing, with or without a rising barometer

> Gusty Winds

            Early on, gusty winds are not negative, but persistent cold northwest air mixed into the epilimnion

            eventually becomes negative. Barometric pressure offers no input as to the pivot point in timing. 

> Falling Air Temperatures

            Falling air temperatures is one of the most negative events in bass fishing,

            especially for Florida-strain bass. Once again, barometric pressure offers no useful input

==============================================================================================================

 

APPROACHING WARM FRONT

The four conditions noted above under 'Approaching Cold Front' also apply to an 'Approaching Warm Front'.

In other words, the barometer cannot differentiate between an approaching warm front and an approaching

cold front (ouch). On the other hand, 'wind direction' quickly and accurately distinguishes an approaching

warm-front from an approaching cold-front. 

 

Roger

 

Thanks for a great post RoLo  !!

 

I have a question if I may , what about diffusion of oxygen ? I will try to explain my question , if the air in the in the atmosphere has a higher concentration of oxygen than water , can the atmospheric pressure play a part in the diffusion of oxygen to shallow waters ? or the surface of waters ?

 

If so , wouldn't the more turbulent waters have a more concentrated level of oxygen from this diffusion ?

[RoLo]

Thanks for a great post RoLo  !!

 

I have a question if I may , what about diffusion of oxygen ? I will try to explain my question , if the air in the in the atmosphere has a higher concentration of oxygen than water , can the atmospheric pressure play a part in the diffusion of oxygen to shallow waters ? or the surface of waters ?

If so , wouldn't the more turbulent waters have a more concentrated level of oxygen from this diffusion ?

 

Thank you Nitro.

 

My answer would be an unqualified, No.

I seriously doubt that atmospheric pressure has any bearing at all on oxygen dissolution.

Surface turbulence certainly does, but that's a different phenomenon.

 

Based on textbook data, oxygen is dissolved in water via 3 processes:

 §  Diffusion

 §  Aeration

 §  Vegetative Output

I think that number can be reduced to two. Oxygen diffusion & Vegetative output.

To mind mind, 'aeration' as simply a violent form of diffusion that occurs for instance

at aerator stations, water fountains and in whitewater rapids. In any case, I don't imagine

that atmospheric pressure has any influence on O2 diffusion (i.e. air-balloon vs. rock analogy).  

 

It's true that oxygen diffusion is only possible when air contains more oxygen than water,

but in the angler's world, that is always the case. Our troposphere is comprised of 21% oxygen

a ratio that isn't altered by wind velocity, relative humidity, air temperature or barometric pressure.

On the other hand, a waterbody that contains 10 ppm dissolved oxygen would be considered

oxygen-rich, though it's only 1/1000 of one percent, a mere pittance compared to 21% oxygen in air

 

As an aside, rainwater contains no oxygen but it would be a mistake to think that rainwater

doesn't oxygenate a lake. The surface turbulence produced by rainfall does aerate the water.

 

Roger

[AK-Jax86]

My buddy use to fish tournaments and he swears by it me I could care less lol. I have this app on my phone and I go by that for my weekend and Monday trips.  All other days I get out when I can but still go by the app. It uses a 4 fish scale so if I see it in the 1 or 2 range I stay close to home and if its 3 or 4 I will venture out to big fish spots.  I believe that app uses the barometer as well but it doesn't hold true in all cases. For instance past few days have been 1 or 2 and me and two of my fishing buddies set our PB.

 

I usually go by the if the fish are hungry they will bite meter

[Nitrofreak]

Thank you Nitro.

 

My answer would be an unqualified, No.

I seriously doubt that atmospheric pressure has any bearing at all on oxygen dissolution.

Surface turbulence certainly does, but that's a different phenomenon.

 

Based on textbook data, oxygen is dissolved in water via 3 processes:

 §  Diffusion

 §  Aeration

 §  Vegetative Output

I think that number can be reduced to two. Oxygen diffusion & Vegetative output.

To mind mind, 'aeration' as simply a violent form of diffusion that occurs for instance

at aerator stations, water fountains and in whitewater rapids. In any case, I don't imagine

that atmospheric pressure has any influence on O2 diffusion (i.e. air-balloon vs. rock analogy).  

 

It's true that oxygen diffusion is only possible when air contains more oxygen than water,

but in the angler's world, that is always the case. Our troposphere is comprised of 21% oxygen

a ratio that isn't altered by wind velocity, relative humidity, air temperature or barometric pressure.

On the other hand, a waterbody that contains 10 ppm dissolved oxygen would be considered

oxygen-rich, though it's only 1/1000 of one percent, a mere pittance compared to 21% oxygen in air

 

As an aside, rainwater contains no oxygen but it would be a mistake to think that rainwater

doesn't oxygenate a lake. The surface turbulence produced by rainfall does aerate the water.

 

Roger

 

BEAUTIFUL !! Thanks RoLo !!!

[Teal]

Dang, yall are some smarter people than me. That high science right there

[A-Jay]

Good Stuff.

 

This is the type of information that you just don't find  on other sites.

 

A-Jay

[senile1]

Nice post, Roger.  When I saw this thread had arisen again, I remembered posts from quite a few years back where the same subject was broached and you responded with similar facts.  I haven't forgotten that lesson.  Barometric pressure changes are accompanied by temperature changes.  After a strong cold front passes, the temperature drops.  Considering the extraordinarily minute effect of barometric pressure, cooler temperatures and the other factors mentioned by Roger are the most likely culprits in poor fishing during the high pressure days after a front. 

 

As for the winds from the east/northeast idea mentioned earlier in this thread, that is also related to the passing of a cold front.  Air circulates in a counterclockwise direction around a low pressure system.  After the low passes, if you are located in the upper northwest quadrant of that low pressure system you will see winds circulating from a northeasterly direction.  Locations directly on the upper side of the low receive east winds.

[Fish'N Impossible]

the barometer has a small effect on bass but there are definately more important factors. I usually approach the water according to a preset attack plan, if that plan doesn't work then I think about pressure systems. During those low pressure times fish a generally very active So alot of moving lures and reaction baits. During those high pressures they tend to be lazier. During high pressures I slow war down jigs dragging the bottom, jerkbaits, and top water. For the most part during higher pressures LMB are deeper/ on bottom and looking up. More due to the bright blue sky's that go with that high pressure.