One of the smallest snooks of the eastern Pacific: silvery, with yellow anal and pelvic fins and a very thick second anal spine. Lives in estuaries and climbs rivers up to about 50 m of elevation; rarely exceeds 37 cm.
Also called: robalo-de-nadadeira-amarela, robalito, róbalo aleta amarilla, Yellowfin snook, Little snook
Choose the place and the species. The index, from 0 to 100, combines weather, sun, moon and tide with each fish's habits. Up to 28 days, with each day's confidence.
location
Sample location: choose yours to see the forecast for where you fish.
period
Reading the weather across 3 global models and 31 simulations…
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index Score from 0 to 100 for the fishing conditions of each hour. It reads weather, sun, moon, tide and the species' habits. It doesn't promise fish: it tells you when the water is on your side. 0–24 poor · 25–44 fair · 45–64 good · 65–84 very good · 85–100 excellent.
today
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confidence —
confidence How much you can trust the weather forecast for the day. It drops with distance and when the models disagree. It is not the chance of catching fish.
models and trend Up to 16 days, three global weather models (the European ECMWF, the American GFS and a high-resolution blend) read hour by hour; when they disagree, the light band on the chart widens. Beyond that it's a trend: 31 runs of the American GEFS model. Confirm when it's 1 week out.
window Consecutive hours with the index near the day's peak and no danger alert. It is the time to have the bait in the water.
hour by hour
slide your finger or mouse over the chart to see each hour
see hour-by-hour table
why this index at —?
next 7 days
choose the day
chart: bar height = day's index · line = variation between models · striped = trend · fainter = less confidence
Each card shows the day's index (0 to 100) and, below it, a strip with the index for each hour, from 0h to 23h. from poor to excellent.
4-week calendar
the fishing month at a glance
plan a trip
what's the best window for the crew?
Choose how many fishing days. We compare each stretch by its average index, discount days with a warning or closed season, and show the 3 best.
trend for the coming weeks
Line: the middle value of 31 simulations of the American GEFS model. Band: where 8 out of 10 fall. Narrow, firm trend; wide, high uncertainty.
the species
everything about the yellowfin snook
overview
who is the yellowfin snook
Small snook of the eastern Pacific, from the southern Gulf of California to Ecuador and Peru. Lives mostly in estuaries and enters fresh water up to about 50 m of elevation; STRI places it at 0 to 25 m. Eats fish, crustaceans and mollusks. It reaches 37.4 cm (standard length) and 626 g, with a common length of about 25 cm. It is one of the smallest snooks in the region and has little sport importance: the Mexican guide consulted describes it as very rare, with specimens taken with cast nets at the mouth of the San José River and at the Loreto marina dock, and more abundant in the southern part of its range.
fun facts
In English it is called yellowfin snook or little snook, for its yellow fins and its size.
The Mexican guide says the thick, long second anal spine is enough to identify it, but the armed snook has a similar spine: also check the yellow of the fins.
how to recognize it
identification
Elongated, flattened body, silvery, with a blue-gray back and a pale lateral line; the head profile is straight to slightly concave. The anal and pelvic fins are yellow, and the base of the pectoral fin is dark. The second anal spine is very thick and long and, bent back, reaches the base of the tail or passes it; the anal fin has 6 rays (rarely 7). The membranes between the dorsal and anal spines are pale. The armed snook (Centropomus armatus) looks similar, but has a very concave head and fins without yellow.
Not found in Brazil. Eastern Pacific, from the southern Gulf of California (Mexico) to Colombia, Ecuador and Peru. In Mexico, the guide consulted places it from Loreto to southern Baja California and along the mainland coast to Guatemala. FishBase lists Mexico, Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica, Panama, Colombia, Ecuador and Peru.
Habitat: Estuaries, bays and lower stretches of coastal rivers; enters fresh water up to about 50 m of elevation.
calendar and clock
when to fish
best season
time of yearbest: Jun–Oct
JanFebSeaAprMayJunJulAugSepOctNovDec
No seasonal study for this species. The app gives more weight to warmer water and to rivers with higher flow, from June to October, when fresh water reaches the river mouths.
best time of day
Dawn and dusk. No dedicated study. The app's estimate follows the snooks: more activity at dawn, dusk and at night, during tide changes.
weather, water and behavior
what affects the yellowfin snook
sensitivity The little bars show how much each factor affects this species. Five full: it feels it a lot.
cold and cold fronts
Cold winter water reduces activity in the bays and at river mouths.
atmospheric pressure
Stable pressure helps; a front with strong wind shuts down fishing.
moon
Full-moon and new-moon tides move water at the mouths and in the channels.
rain
A rising, muddy river scatters the fish; clearing water afterwards is good.
water level
Falling river concentrates snook at mouths and channels.
noise
Sensitive to noise and to shadow on the water; arrive by oar or electric motor.
wind
Strong wind makes precise casting near roots and logs difficult.
tide
Ebb tide at river and lagoon mouths is usually the best.
depth
From 0.5 to 5 m, near logs, roots and current breaks.
single hook no. 2 to 1/0; circle hook 1/0 to 2/0 on live bait
lures
mid-water jerkbait, 7 to 10 cm
silicone shad on a light jig head
small stickbait at dawn
streamer for fly fishing
natural baits
live shrimp
small live or dead baitfish
accessories
alicate
small boga-grip
polarized glasses
tip from an angler
Cast tight to the roots and along the edge of the channel and retrieve with pauses: the snook hits the bait that comes out of the shade carried by the current.
what the law says
rules for the yellowfin snook
Summary of the regulations we found, with the source for each. Rules change; before keeping or transporting fish, check with the state environmental agency. Conservation: Of least concern globally. Not listed in Mexico's NOM-059-SEMARNAT-2010. According to the 2021 fisheries management plan for Nayarit and southern Sinaloa, the snooks of the Mexican Pacific have no closed season or minimum size of their own.
Mexico: up to 5 per species and 10 saltwater fish per day
5 specimens of the species per angler per day, within the limit of 10 saltwater fish
In recreational sport fishing in Mexican federal waters, each angler may keep up to 10 marine fish per day, no more than 5 of the same species. The yellowfin snook is not among the species reserved for sport fishing (marlin, sailfish, swordfish, "sábalo o chiro," roosterfish and dorado, up to 50 nautical miles from shore, item 0.3 of the standard) and has no quota of its own. Fish over the limit go back alive (item 4.9.5), and sport-caught fish may not be sold. Anglers fishing from a boat need the permits of the Federal Duties Law; anglers fishing from shore do not (item 4.3).
Personal Incopesca license, for people over 16confirm with the agency
In the regulation of the Fisheries and Aquaculture Law (Decree 36782, of May 24, 2011), art. 69, sport fishing is authorized only for natural persons over 16, with a license issued by Incopesca; tourists, whether national or foreign, also need the license. Art. 68 limits the landing of large pelagics to 5 per trip, and art. 66 promotes catch and release, but the rule sets no quota for this species. The decree was later amended (Decree 39458), so confirm the current rule with Incopesca.
Panama: new sport fishing decree in force from Dec 10, 2026
Executive Decree No. 9 (Jun 10, 2026), in force from Dec 10, 2026confirm with the agency
ARAP published Executive Decrees No. 9 and No. 10, of Jun 10, 2026, in the Official Gazette. The first regulates sport fishing throughout the territory; the second protects billfish (sailfish and marlins). Both take effect on Dec 10, 2026, after six months of adaptation. We did not verify the text: the press report gives no catch limits, sizes or license requirements. Before fishing in Panama, check with ARAP.
Colombia: AUNAP license and catch-and-release in sport fishing
Individual AUNAP license; catch-and-release guidanceconfirm with the agency
AUNAP Resolution 0549 of 2022 sets the guidelines for sport fishing for recreational purposes in Colombia. Anyone fishing needs a permit: for a natural person, Colombian or foreign, it is a personal, non-transferable license (art. 6). The rule uses "capture and release" as guidance. We did not verify the daily limit or the minimum sizes by species: check with AUNAP before keeping any fish.
catch and release Releasing the fish alive, quickly and with a wet hand. During a closed season it isn't always allowed: what the regulation says applies.
Hold it by the mouth with a wet hand, support the belly, and watch the sharp edge of the gill cover and the anal spines. Release it facing the current, only once it swims on its own.
in the kitchen
White flesh, considered excellent when it is for sale; yields little fillet because it is small.
calculator
how much it weighs without taking it out of the water
Length-weight relationship W = a·Lb (a = 0.00759, b = 3.05; FishBase (relação peso-comprimento bayesiana, estimativa da própria espécie)). It's an average: a fat or lean fish can vary by 10% to 20%.
estimated weight
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sources and references
The season weights (months), time of day and sensitivities (cold, pressure, moon, wind, rain, tide, strong light, murky water and noise) are the app's editorial estimates, based on the literature below and on field experience of anglers and guides. They are not official data or measurements made for this species, and may vary by region and year. Closed seasons and legal rules appear in the rules section, with the standard and a link. The common size starts from FishBase's common length (25 cm), and the common weight is calculated from the length-weight relationship.
technicalMexican Fish (mexican-fish.com): ficha do Yellowfin Snook (Centropomus robalito)Independent guide to Mexican Pacific fishes, with photos of catches and the author's observations; not an official source. Page checked on 13/10/2026. It gives the distribution in Mexico, the specimens from Loreto and the mouth of the San José River, and how to tell it apart from the other snooks.
The weather comes from three independent global models, cross-checked hour by hour: when they agree, confidence goes up; when they diverge, the band between them shows on the chart. Beyond 16 days, we use the GEFS ensemble of 31 simulations: if 20 of the 31 predict rain, the chance of rain is 65%. Sun and moon are calculated astronomically, with no uncertainty.
The index adds up, weighted for each species: time of day (species curve anchored to real sunrise and sunset), moon (transits, rise and set, phase), pressure (3 h trend and 24 h swing), water temperature (in rivers, estimated from air temperature; at sea, estimated by an ocean model), wind, rain, clouds, tide and the month in the species' cycle.
Accuracy measured in the reference project (4 regions, 93 days, forecast vs. observed): maximum temperature is off by 0.6 °C on average the next day and 1.7 °C at 7 days; rain of 5 mm or more is detected 76% of the time the next day and 57% at 7 days. Detection isn't everything: the false alarm rate isn't published here yet, and 93 days in 4 regions is still a small sample. We now also measure every day, at the app's destinations:
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Your location is saved only on this device and feeds the forecast, the map and the "today" on the home page.
