The North Atlantic low north of Puerto Rico is likely to pass close to Lisbon on Wednesday afternoon

Quick answers

As of the Mon 9 Nov 18Z – Tue 10 Nov 12Z model runs · updated Tues., Nov. 10, 5:44 p.m. WET

Where is the North Atlantic low north of Puerto Rico going?

The centre is about 550 kilometres south of Ponta Delgada, moving east at about 75 km/h. The most likely path takes it about 220 kilometres northeast of Rome by Friday evening.

When will the North Atlantic low north of Puerto Rico be closest to Lisbon?

Most likely Wednesday, Nov. 11, around 4 p.m. WET. Across the forecasts the closest pass comes between Wed 2 p.m. and Wed 5 p.m. WET. Most forecasts pass the centre 20–500 kilometres from Lisbon.

What is the chance it passes within 160 kilometres of Lisbon?

83%: 8 in 10 forecasts bring the storm’s centre within 160 kilometres of Lisbon. Elsewhere: Genoa 74%, Marseille 69%, Madrid 52%, Rome 17%. Rain, wind and coastal flooding can reach well beyond 160 kilometres from the centre.

How much rain could Lisbon get while the North Atlantic low north of Puerto Rico passes?

From Tue 6 p.m. (when the forecast’s rain totals start) to Wed 6 p.m. WET, the end of the window when its centre is closest to Lisbon, the middle of NOAA’s 31 GEFS forecasts brings 54 mm of rain and melted snow to Lisbon; nearly all bring 13 mm or more and nearly all bring 25 mm or more; 6 in 10 bring 51 mm or more. By Wed noon, when that window opens, the middle forecast already has 37 mm. That is all the rain in that time, not only the North Atlantic low north of Puerto Rico’s, from one model (GEFS) on a coarse grid; local official forecasts can differ. Lisbon: rain and wind this week →

How sure is the forecast?

Path certainty: low. 184 of 185 ensemble forecasts show the storm, and they disagree on where it goes. Little has changed since the previous run.

Do the AI and physics models agree?

Largely, yes. Chance within 160 kilometres of Lisbon: AI ensembles (AIFS ENS, AIGEFS) 82%, physics ensembles (GEFS, ECMWF ENS, GEPS) 84%. By model: GEFS 97%, ECMWF ENS 76%, AIFS ENS 82%, AIGEFS 81%, GEPS 86%. By Thursday evening the AI ensembles’ middle track is about 80 kilometres northeast of the physics ensembles’. Both take it to about 982 mb at its deepest.

Will the North Atlantic low north of Puerto Rico become a bomb cyclone?

24% of forecasts (2 in 10) deepen it fast enough to count as a “bomb” (a pressure fall of roughly 24 millibars 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.