ENSO Atlas + Radar · El Niño & La Niña Tracker, Storm Outlooks and Live Radar

🔔 Alerts

Get told when something important changes. ENSO Atlas checks every time you open it, and on phones that support it, once or twice a day in the background.

El Niño or La Niña starts or ends A big jump in Pacific temperatures (0.5°C or more) My tornado or hurricane season outlook changes

El Niño / La Niña outlook

Where the Pacific is heading

Odds for each upcoming season

Each bar is one upcoming three-month season, split by how likely each state is. Hover or tap a bar for the exact numbers.

Show the numbers as a table

Season	Most likely	El Niño	Neutral	La Niña	Expected Pacific temperature

This is a statistical guide built from NOAA's records. For decisions that matter, check NOAA's official ENSO outlook, which also uses climate models and expert judgement.

The equatorial Pacific right now

Move over the ocean (or tap it) to read the temperature difference at any spot. The dashed box is the Niño 3.4 region.

The four regions forecasters watch

Average difference from normal inside each box today. Niño 3.4 is the one that officially decides El Niño and La Niña.

What you are looking at

The map shows ocean temperature compared with normal, not the temperature itself. Red means the water is warmer than it usually is on this date, blue means cooler, and pale means about normal.
A red tongue along the equator is El Niño. Warm water spreads east from the middle of the Pacific toward South America. The redder and wider it is, the stronger the event.
A blue tongue is La Niña. Cold water rises off South America and spreads west along the equator.
Why it matters here: that patch of ocean is big enough to shift the jet stream, which steers storms across North America months later. That is why the rest of this app starts with it.
Why today’s number can differ from the ENSO page: this map is a single day. The official El Niño / La Niña reading is a three-month average, so it moves more slowly and lags behind what you see here.
How fresh it is: NOAA builds a new map once a day from satellites and ocean buoys, usually a day behind. The app checks for a newer one automatically while you have it open.

Live radar and chase map

NEXRAD weather radar, the chase score and its ingredients, and the official severe thunderstorm outlook. Click anywhere on the map for the chase score there.

Chase map layer

Loading the forecast map…

Severe thunderstorm outlook

Official outlook (SPC)

Radar and imagery

Radar (NEXRAD)

Clean radar: hide clutter and faint echoes

Velocity, nearest radar

Lightning (strike density, last 15 minutes)

Satellite

Replay the radar for a past day

What do these numbers mean?

Chase score (0–100) is this app's own rule of thumb combining instability, shear, moisture, the cap and the chance storms form. It is not an official product.

CAPE (J/kg) is storm fuel: how buoyant the air is. Over 1,000 supports strong storms; over 2,500 is a lot.

CIN (J/kg) is the cap holding storms down. A little keeps storms isolated; over about 200 usually stops them.

Dewpoint (°F) is low-level moisture. Tornado setups usually want 60°F or more.

Shear (knots) is how much the wind changes with height. Over about 35–40 kt lets storms rotate; strong shear in the lowest 1 km favours tornadoes.

Helicity (SRH, m²/s²) measures how much the low-level wind would make an updraft spin. Over 100 in the lowest 1 km is notable; over 250 is a lot.

Cloud base (LCL) is how high storm bases would be. Tornadoes favour low bases, under about 1,000 m.

STP (Significant Tornado Parameter): 1 or more has historically gone with strong tornadoes. SCP (Supercell Composite): above 1 favours supercells.

Lifted index is another instability measure: the more negative, the more unstable.

STP, SCP and helicity are worked out here from forecast-model data, so treat them as estimates. For decisions that matter, go by the Storm Prediction Center outlook and National Weather Service warnings.

Forecast model data: NOAA GFS. Outlooks: NOAA Storm Prediction Center. Radar, satellite and velocity: Iowa Environmental Mesonet. Lightning: NOAA nowCOAST. The chase map and radar cover the United States.

How this app works

We look at your recent weather. The last few weeks of temperatures and rain or snow at the spot you picked.
We find look-alike years. Past years (back to 1981) whose weather on the same dates was most similar. Forecasters call these “analog years”.
We show what happened next. The weeks that followed in those years, averaged together, give a rough outlook for the weeks ahead.
We look up the tornado season that came after. For each look-alike year, how many tornadoes were recorded within your chase range in the following March–June, and whether that counted as an active, average or quiet season for the area.
We look up the hurricane season that came after. How many tropical storms and hurricanes formed in the Atlantic or the Eastern Pacific, how strong they were, and which ones passed within your chase range. El Niño years usually mean fewer Atlantic hurricanes and La Niña years more.

El Niño and La Niña are natural swings in tropical Pacific Ocean temperature that shift weather around the world. El Niño means the ocean is warmer than usual, La Niña means cooler than usual, and Neutral means neither. Everything on this page is built around it: the app starts with years in the same state as now, ranks them partly by how similar the strength of the event was, and shows what every El Niño, neutral and La Niña year on record did for comparison.

“Normal” means the average for these same dates across all the past years searched.

Not a warning service. ENSO Atlas looks months ahead using history. It cannot tell you about a storm happening today. For watches and warnings, follow the National Weather Service (weather.gov), local radio and TV, and the emergency alerts on your phone.

Questions or problems? Email ensoatlaswx@gmail.com. See also the Terms of Use and Privacy Policy.

Tornado counts only include tornadoes rated EF1 or stronger, because weaker ones often went unrecorded in older decades and would make early years look quieter than they were.

Which past years should we compare with?

Map:

Show:

Every hurricane season on record

Storm tracks in those seasons

🎯 How has it done here?

Year	Pacific then	Weather ahead	Tornado season	Hurricane season

Analog years

Click a year to pick it out in the charts and maps on the other pages. Match score: the lower the number, the more that year resembled this one.

Year	Pacific state	Match score
Year	Pacific state	Match score	Avg high	Avg low	Precip	Avg high	Avg low	Precip	High vs normal	Tornadoes	Tornado days	Season	Biggest day	Named storms	Hurricanes	Came within range

This is a rough guide based on history, not a precise forecast. Past look-alike years often disagree with each other, so check the agreement before relying on it. ENSO Atlas is not a warning service. For watches and warnings, follow the National Weather Service (weather.gov), local radio and TV, and emergency alerts on your phone. Weather data: NASA POWER daily history (MERRA-2 reanalysis, 1981 to present). ENSO index: NOAA Oceanic Niño Index. Tornado records: NOAA Storm Prediction Center (United States only). Hurricane records: NOAA National Hurricane Center (Atlantic and Eastern Pacific). Hail and wind reports: NOAA Storm Prediction Center. Radar, velocity and satellite: Iowa Environmental Mesonet; lightning: NOAA nowCOAST. Ocean temperature map: NOAA OISST via NOAA CoastWatch. Terms of use · Privacy policy.