Bass Pulse is a bass fishing forecast tool based on Buck Perry's cold front cycle, refined with research and wisdom from over a dozen bass fishing experts and fisheries scientists.
Visit /fish, type your location into the input bar, and click Analyze. The input accepts any of:
28115RenoMooresville, NC35.58, -80.81You can also link directly to a forecast with URL parameters:
/fish?zip=37211 Nashville, TN (by zip code) /fish?lat=28.54&lon=-81.38 Orlando, FL (by coordinates)
Bookmark a URL with your home zip and the page loads straight to your forecast.
Bass Pulse is not a generic weather forecast. It is a system specifically tuned to translate atmospheric conditions into bass behavior. Here is how, step by step.
For your location, Bass Pulse pulls hourly data from a curated list of 176 commercial-grade airport weather stations across the country, plus your nearest local station. Why multiple? Cold fronts span hundreds of miles, and any single station can miss a front or trigger a false alarm. By cross-referencing the five nearest major stations and requiring consensus among them, the system filters out station-specific noise and locks onto real, regional weather events.
Perry's cycle is anchored to one event: the passage of a cold front. Bass Pulse's detector scans seven days of hourly atmospheric data looking for the signature of a real front: a sharp wind shift to the northwest, a sudden drop in dew point, a barometric pressure swing, and a confirming temperature drop. Each candidate is scored, and only those passing a calibrated confidence threshold count.
How well does this work? We tested 540 different parameter combinations against 35,909 hourly observations and 234 ground-truth fronts at a single station over five years. After tuning, false positives dropped 87% while real fronts kept getting caught.
Once a front is locked in, the math is simple in concept and tricky in practice. Bass Pulse calculates how many hours have passed since the front and maps that onto Perry's seven-day cycle. But the cycle is not a stopwatch. It stretches in summer, compresses in spring, and changes character with the seasons. The system adjusts cycle length based on the calendar period (pre-spawn, summer peak, fall turnover, and so on) and bends the timing based on your latitude. A Maryland angler experiences the cycle differently from a Florida angler in any given month.
Cycle math gives a starting hypothesis, but the atmosphere does not always cooperate. Bass Pulse confirms its hypothesis against the conditions you would actually feel right now: the wind regime, the dew point classification, the pressure trend, the cloud cover, and overnight temperature behavior. If reality strongly disagrees with the cycle math, the system trusts reality and falls back to a trend-based classification.
The base rating from the cycle is then adjusted up or down by rules drawn directly from research:
These rules are not tuning knobs we made up. Each is documented in published research or decades of tournament-pro experience. See The Experts.
For the seven-day strip, Bass Pulse pulls forecast model data at hourly resolution and runs the same front detection and cycle assignment forward in time. Predicted fronts reset the cycle in the strip just like real ones do. Confidence decays with distance from today, which is why each forecast card shows its own confidence percentage.
Some signals are popular in the fishing world but unsupported by science. Bass Pulse does not use them as rating drivers:
A single rating, LOW, MODERATE, STRONG, or PEAK PULSE, that tells you what bass behavior to expect. Backed by multi-station weather data, calibrated against five years of historical fronts, modified by published research from twelve experts, and updated continuously. Every time you check the app, the algorithm runs fresh.
| Rating | Perry Day | What It Means |
|---|---|---|
| LOW PULSE | Day 1-2, 7 | Bass are deep, tight to cover, and feeding is minimal. Post-frontal conditions dominate. Go finesse: micro-jigs in heavy cover (Schramm) or deep stitching (Murphy). Any fish you catch are earned. |
| MODERATE PULSE | Day 3 | Activity building. Cold front effects fading. Short feeding windows at dawn/dusk and on windblown banks. Worth the trip with the right approach. |
| STRONG PULSE | Day 4 | Bass are moving and feeding. Return flow established with south winds and building moisture. Two movement periods: mid-morning and mid-afternoon. Prime conditions. |
| PEAK PULSE | Day 5-6 | Full migration to the shallows. Heavy cloud cover, falling pressure, muggy air. Fish are aggressive and feeding recklessly. Best window of the cycle. Get on the water. |
Buck Perry (1915-2005), the father of structure fishing, observed that bass behavior follows a repeating cycle driven by cold front passages. After a front clears, fish retreat to deep water and go inactive. Over the following days, as the atmosphere reloads with moisture and cloud cover builds, fish gradually move shallower and resume feeding, peaking just before the next front arrives.
Buck Perry described a clean seven-day cycle because it was the simplest way to teach the pattern. And he was right about the pattern. But weather does not run on a calendar, and Perry knew that.
In the real world, cold fronts don't show up every seven days like clockwork. In spring, they can roll through every four or five days, barely giving the cycle time to reach the good stuff before the next front slams the door shut. That's why spring fishing can feel so frustrating. You are living in Days 1 through 3 for most of the time.
Summer is the opposite. High pressure systems park themselves over the Southeast for weeks. No front in sight. The cycle stretches out to ten, twelve, even fourteen days. When that happens, the fishing doesn't just stop at Day 7 and wait for a reset. You get an extended run of good conditions: south winds, warm dew points, building clouds. The bass stay active and some of the best fishing of the year happens during these long, stable summer patterns when the atmosphere just keeps reloading without a front ever arriving to shut things down.
Fall is its own animal. The first cold fronts of September actually help. They break up the thermal layers in the lake, push oxygen-rich water down to the fish, and trigger aggressive feeding. A Day 1 in September does not fish like a Day 1 in April.
Winter compresses everything differently. Fronts are stronger, the dead zone lasts longer, and recovery is slower. The cycle could stretch to nine or ten days, but the fish never fully ramp up to a Day 5 or 6 level because the water's too cold for aggressive shallow feeding. Break out the A-Rigs, jerkbaits, and pray for a bite.
The point is this: Perry's seven days are a framework, not a stopwatch. But the sequence is always the same: Dead water after the front, gradual recovery, peak fishing as the next system approaches. What changes is how fast or slow the atmosphere moves through those phases. Bass Pulse reads the actual conditions, the wind, the dew point, the clouds, the pressure, and figures out where you are in the cycle regardless of whether it's been 5 days since the last front or 15.
If you only look at one number on Bass Pulse, make it the wind. Wind direction tells you exactly where you are in the cold front cycle, and wind speed is probably the single biggest factor in whether bass are actually catchable.
After a cold front blows through, the wind always tells the same story. It starts from the northwest, cold and dry. Over the next several days it rotates clockwise through the compass. When it finally locks in from the south or southeast, that warm moist air is your green light. Here's what that looks like day by day:
This is not random. This is also where we all wished we'd paid closer attention to the weather module in 8th grade science class. After a cold front pushes through, a big high pressure cell settles in behind it to your northwest. Cold, dry air moves in on that NW wind and the fish absolutely hate it. They are somewhat in retreat mode. But that high doesn't stay put. Weather here in the US almost always moves west-to-east, so the high slowly drifts past you. As it slides to your east, the wind at your location rotates clockwise around it: from the northwest, to the north, to the northeast, to the east, to the southeast. By the time the high is well past you, warm air from the Gulf of America is flowing back in from the south. That's your return flow, and that's when the fishing really gets good.
In practice, this shift isn't always a smooth spin through every compass point, that would be way too easy. Some days the wind just goes from "cold and from the north" to "hey, it's suddenly from the south." The atmosphere skips steps sometimes. But the direction of the rotation is always the same: clockwise, NW to S, every. single. time. That's just how weather works on Earth, over this North American continent we live and fish in.
Bass Pulse classifies wind into three regimes: Post-Frontal (NW through NE, the bad days 😭), Transitional (the in-between 🫤), and Return Flow (SE through SW, the good days 🎣 ☀️ 🐟 🎉 🙌). When you see the wind card flip from Post-Frontal to Return Flow, the fishing is about to turn on.
Direction tells you where you are in the cycle. Speed tells you how catchable the fish are right now.
Josh Alwine analyzed over 40,000 bass catches, and found that catch rates more than doubled when wind exceeded 15 mph! It didn't even matter which direction the wind was blowing. A windy post-frontal day outfished a calm return-flow day. Wind was the single biggest catch rate multiplier in his entire dataset.
Why? Because of what wind does to the water's surface. Cue Buck Perry teaching us about LIGHT.
Al Lindner called wind "a mechanical canopy." Surface chop scatters and breaks up sunlight the same way cloud cover does, creating low-light conditions underneath. A windy, clear day can fish like an overcast one. Lindner taught that you should always be looking for windblown banks, points, and riprap, because those spots concentrate both baitfish and feeding bass.
Think about it this way: bass have no eyelids. In calm, clear water on a sunny day, they are squinting. They retreat to shade, deep water, or heavy cover to escape the light. But add 15 mph of wind and suddenly the surface is choppy, the light is scattered, and bass feel comfortable roaming and feeding in shallower water.
Bass Pulse upgrades your rating when wind is strong, even on otherwise tough post-frontal days. If you see wind over 15 mph on the app, pay attention. That is the single biggest "go anyway" signal in the system. Fishing in the wind usually sucks, unless you are catching 10lb bass. Go!
What is dew point? It's the temperature at which the air can't hold any more moisture and water starts condensing (fog, dew on your car, clouds forming). It is NOT the current air temperature. A dew point of 26°F doesn't mean it's freezing outside. It means the air is very dry. Think of it as a moisture meter for the atmosphere:
Dew point is more useful than humidity or "feels like" because those numbers shift with temperature throughout the day. Dew point stays stable. If the dew point is 26°F at dawn, it'll still be close to 26°F at noon even as the air temperature climbs 20+ degrees. That consistency makes it a reliable signal for tracking the atmosphere's recovery after a front.
Buck Perry described the ideal pre-frontal conditions as "muggy, overcast, with a south wind." Dew point is the best single number for measuring that mugginess. When dew points are high, cloud cover is usually building, and fish are moving shallow.
Bass Pulse classifies dew point as Dry, Moderate, or Moist and uses it to confirm where you are in the cycle. A rising dew point on Day 3 can signal the fish are about to turn on earlier than expected.
Light penetration is the single most important factor controlling bass feeding behavior. This is Buck Perry's core insight, and modern science has confirmed it over the last 50 years from multiple different angles.
Ralph Manns ran a multi-year field study on Lake Travis and found that 42% of bass were actively feeding under overcast skies, compared to just 28% under clear skies. That's a 50% increase in feeding activity when light is filtered!
Dr. Loren Hill discovered that on clear, sunny days, photosynthesis in shallow water strips out CO2 and spikes pH levels. This creates a zone of respiratory distress for bass from roughly 11:30 AM to 6 PM. Fish avoid it by going deep or tucking into heavy shade. This is why you don't catch many fish during this window.
Dr. Keith Jones, a fisheries biologist, measured how fast bass can adjust their eyes to changing light. Bass need about 20 minutes to adapt their pupils. Their prey (mostly bluegill and shad) need even longer. When light changes suddenly, like at dawn, dusk, or when a cloud bank rolls in, bass have a temporary visual advantage and feed aggressively.
Bass Pulse shows the current light intensity (Low, Transitional, Filtered, Moderate, High, Intense) by combining time of day, cloud cover, and wind chop. Lower light means more active fish.
Barometric pressure is the most misunderstood factor in fishing. Many anglers believe falling pressure triggers feeding and rising pressure shuts it down. The science says otherwise.
Dr. Hal Schramm, a fisheries scientist at Mississippi State, calculated that a bass swimming down just 3 feet experiences a greater pressure change on its body than a Category 5 hurricane creates at the surface. Fish live in a world of constant, massive pressure changes every time they move up or down in the water column. Atmospheric pressure swings are biologically irrelevant to them.
So why does fishing seem to change with pressure? Because pressure is correlated with weather patterns. Falling pressure means clouds are building and a front is approaching (good fishing). Rising pressure means a front just passed and skies are clearing (bad fishing). It is not the pressure itself. It is the cloud cover, wind, and the light conditions that come along with it. (We're starting to understand, Buck!)
Doug Hannon, known as "The Bass Professor," documented that trophy bass (10 lbs and over) fed most reliably during extended periods of pressure stability, 48 hours or more of steady readings. His theory: big bass are creatures of routine, and stable conditions let them settle into predictable feeding patterns.
Bass Pulse tracks pressure trends and displays a "TROPHY WINDOW" when pressure has been stable for 48 or more hours. The pressure reading itself is shown for reference, but it does not drive the rating.
Moon phase is one of the most debated topics in fishing. Some anglers swear by it. Let's just say the research is mixed here.
Doug Hannon claimed that 75% of IGFA world record bass were caught within 3 days of a full or new moon. This statistic has been widely repeated in fishing media for decades.
Josh Alwine reanalyzed Hannon's data using real statistical methods, and found the correlation largely disappears when you correct for sample size and methodology. In his own 40,000-catch dataset, moon phase had no statistically significant effect on catch rates.
Bass Pulse displays moon phase for your reference (or for pure entertainment) but does not use it to change the rating. Many experienced anglers still plan trips around lunar cycles, and it's easy to show the information, as the moon is HIGHLY predictable. Just know that the cold front cycle and light conditions have far stronger scientific backing. But we show it because sometimes superstition supercedes science, and we get it. This is fishing after all.
The same cold front hits differently depending on the time of year. Bass Pulse adjusts the cycle based on the seasonal calendar.
Kevin VanDam (aka KVD), the most successful tournament bass angler in history, considers photoperiod (the day length) the master clock for bass behavior. Day length tells bass when to spawn, when to feed heavily for winter, and when to transition between seasonal patterns. VanDam says photoperiod trumps water temperature as the primary seasonal trigger. And KVD is right. We all know fishing is better in the summer, but why?
Al Lindner developed the "Calendar Periods" framework that divides the fishing year into distinct phases: pre-spawn, spawn, post-spawn, summer peak, fall turnover, and cold water. Each period changes how bass respond to weather.
Key seasonal effects on the cold front cycle:
Bass Pulse shows the current seasonal period, total daylight hours, and whether days are getting longer or shorter. This helps you understand the bigger picture beyond just the current front cycle.
Bass Pulse incorporates documented research from these 12 anglers, biologists, and researchers. Dig in.