StormlinesStorm tracks, explained
Nerd mode: every forecast, readouts, filters and range & bearing for weather enthusiasts

Sections

View
Nerd mode: every forecast, readouts, filters and range & bearing for weather enthusiasts

StormSouth Pacific

The South Pacific low south of French Polynesia could deepen rapidly into a “bomb” by Friday

South Pacific — Deep low bottoming out near 974 mb Fri afternoon, in the South Pacific; all 185 ensemble forecasts show it.

Updated Wed., Nov. 11, 9:41 p.m. UTC · 185 forecast tracks from NOAA, ECMWF and Environment Canada: high

South Pacific — Deep low bottoming out near 974 mb Fri afternoon, in the South Pacific; all 185 ensemble forecasts show it.

Quick answers

As of the Wed 11 Nov 12Z model run · updated Wed., Nov. 11, 9:41 p.m. UTC

Where is the South Pacific low south of French Polynesia going?
The centre is near 33°S 128°W, moving southeast at about 70 km/h. The most likely path takes it in the South Pacific by Saturday evening.
How sure is the forecast?
Path certainty: high. All 185 show the storm, and they closely on its path. Little has changed since the previous run.
Do the AI and physics models agree?
Largely, yes. By Friday night their middle tracks are almost on top of each other. Both take it to about 974 at its deepest.
Will the South Pacific low south of French Polynesia become a bomb cyclone?
95% of forecasts (9 in 10) deepen it fast enough to count as a (a pressure fall of roughly 24 in 24 hours, adjusted for latitude).

New to these maps? Read how to read a spaghetti map, or see the week’s rain and wind around the world on the globe.

What we know

Where it is. At 10 p.m. Wednesday, the centre was near 33°S 128°W, with a central pressure near 1,000 .

How sure. All 185 show the storm, and they closely on its path. Little has changed since the previous run.1

How strong. It is still strengthening: forecasts deepen it to about 974 by Friday afternoon. Nine in 10 forecasts make it a , deepening about 24 millibars or more in a day.

What’s uncertain

Later on. The forecasts fan out after Saturday. By Saturday evening, the is about 800 kilometres across.2

When it arrives

No town we track is within reach of this storm; it stays near 33°S 128°W.

What the forecasts said vs what happened

Collecting: so far at most 3 runs of any one model made 1 day ahead can be checked. We show how the forecasts did once a model has 4. How good are the forecasts this season?

DetailsStrength, sources and the fine print

How strong it gets

Central pressure over time. The line is the middle forecast; the band holds 8 in 10 of them.

(lower is stronger)

Times are shown in

Where the forecasts come from

ModelTracksStatus
NOAA
31 of 3112Z
arrived 4 h 10 min ago
Latest run
ECMWF
51 of 5112Z
arrived 17 min ago
Latest run
ECMWF
51 of 5112Z
arrived 3 h ago
Latest run
NOAA
31 of 3112Z
arrived 1 h 25 min ago
Latest run
Environment Canada
21 of 2112Z
arrived 4 h 27 min ago
Latest run

Also tracking

  1. North Pacific low west of British ColumbiaLikely to pass 20–210 km S of Anchorage Wed night; 7 in 10 forecasts bring it within 160 km
  2. North Atlantic lowLikely to pass 15–130 km from A Coruña Fri night; 9 in 10 forecasts bring it within 160 km
  3. Southern Ocean lowVery deep low bottoming out near 950 mb Wed night, in the Southern Hemisphere; all 185 forecasts show it
  4. Southern Ocean lowVery deep low bottoming out near 954 mb Wed night, in the Southern Hemisphere; all 185 forecasts show it
  5. South Atlantic lowVery deep low in the Southern Hemisphere, near 958 mb now and filling; all 185 forecasts show it
  6. See all 24 storms →

Notes

  1. Forecast tracks from the 12Z model run: GEFS (31), ECMWF ENS (51), AIFS ENS (51), AIGEFS (31), GEPS (21). A single run is one high-resolution forecast; ensemble forecasts are the same model run many times with small changes.
  2. The cone encloses where the centre is expected to be about two times in three at each hour, from the spread of the forecasts, widened by 20 percent; not yet calibrated against past storms. It shows uncertainty in the track, not the size of the storm.
  3. Shading shows the share of forecasts that bring the centre within 160 kilometres of a spot at any time in the next 9 days. Rain, wind and surge can reach much farther.
  4. Times are in your time zone. Arrival windows run from the earliest to the latest closest approach across forecasts that bring the centre within about 300 miles (500 km).
  5. NOAA/NCEP.
  6. Data Source: Environment and Climate Change Canada.
  7. This service is based on data and products of the European Centre for Medium-Range Weather Forecasts (ECMWF). Source: www.ecmwf.int. Licence: CC BY 4.0.
  8. Cyclone tracks computed by Stormlines from the model fields.
  9. Reading these maps: , or the illustrated guide to spaghetti models. The week’s rain, wind and temperature everywhere: the Stormlines globe.
  10. How often these forecasts turn out right: the season’s forecast check, AI vs physics.
  11. Stormlines storm ID: L-2026-2582.

Stormlines draws every storm the world’s ensemble forecasts can see: tracks from NOAA (GEFS and the AI ensemble AIGEFS), ECMWF (ENS and the AI ensemble AIFS) and Environment Canada (GEPS), updated as each model run lands. Coastlines and place names from Natural Earth; sea areas from IHO Sea Areas, version 3 (Flanders Marine Institute, marineregions.org, CC BY 4.0; modified: simplified, some islands removed, names edited).

Not an official forecast. For warnings and decisions, follow your national weather service.

Made by 1F2T LLC

Loading 185 tracks…

Stormlines Tracks: NOAA, ECMWF, Environment Canada

Full forecast
Through Sat 6 p.m. UTC