Hurricane tracks

Tropical Disturbance Julio Model Accuracy: DeepMind vs GFS vs WeatherNext 3

Final advisory

NHC issued its final advisory at 2:00 PM ET Tue, Aug 25.

Tropical Disturbance Julio has 24 positions on the best track, which is where the storm actually went, from the operational NHC file. 4 official forecast tracks are drawn. At 12 hours, the average track miss is 56 miles across 3 forecasts. At 12 hours, the official wind forecast averaged 44 mph and where the storm actually went averaged 48 mph. Stored model tracks on these forecast tracks: GFS, GEFS mean, Canadian GEM, UKMET, HAFS-A, HAFS-B, HWRF, HMON, NAVGEM, Google DeepMind, WeatherNext 3.

EP102026 · 2026 · Aug 20-25, 2026. Score table. Damage reports.

How to read this. The solid line is where the storm went. A dashed line is where the official forecast said it would go. A smaller path miss is closer. Distances are statute miles. Wind speeds are miles per hour.

The technical details

Path miss on this page is the great-circle distance in statute miles, the same miles as the home card and the score table. The Earth radius is 3,958.7613 miles. The file also keeps that distance in nautical miles. One nautical mile is 1,852 meters, about 1.15 statute miles. A case counts when that forecast and the best track (BEST, lead 0) share the same valid time. Positions are not interpolated. A model track counts even when that cycle has no official forecast yet. Skill against the official forecast (OFCL) still requires the official forecast from the same issue time and lead.

Shown leads are 12, 24, 36, 48, 60, 72, 96, and 120 hours, once a paired fix exists. Sample size is the number of paired cases at that lead. Overall rank still uses 24, 48, 72, and 120 hours. The 96-hour lead is drawn when the deck has a paired fix, and it is not in that rank.

Wind on this page is miles per hour. The file stores maximum wind in knots. One knot is about 1.15 miles per hour. An advisory wind is rounded to the nearest 5 mph. A mean on this page is rounded to the nearest mile per hour. Wind miss is the absolute difference on the paired cases. There is no confidence interval on this map. The daily board’s interval is a 95% percentile bootstrap.

Overall rank is the average of the path rank and the wind rank on this storm. Each rank uses the graded leads at 24, 48, 72, and 120 hours, and each of those leads counts once, however many forecasts it holds. A lower miss is the better rank. A tie shares the average of the places those forecasts occupy. A source is ranked only with at least 3 graded forecasts for path and 3 for wind. Fewer than that says Not enough forecasts yet. A source with no graded path, or no graded wind, is left out of both ranks, and overall shows —.

The best track is the operational NHC b-deck. It is preliminary and revised after the season. HURDAT2 is not loaded. Model lines come from the public a-deck for the same forecast tracks, and only when that file stores them. Google DeepMind is the Weather Lab operational ensemble mean. WeatherNext 3 is that model’s ensemble mean from the same download. ECMWF AIFS, ECMWF HRES, and the ECMWF ENS mean are tropical-cyclone tracks from ECMWF open data. The ECMWF ENS mean is the average of the member centers in the IFS ensemble track file. AI GFS is NOAA’s AIGFS tracker when that file is still posted. The methodology page names the aids that are scored.

The methodology page is the full reference. How we grade says the same rules in plain English.

The best track is the operational NHC b-deck. It is preliminary and is revised after the season. The post-season HURDAT2 track is not loaded.

ECMWF AIFS, ECMWF HRES, ECMWF ENS mean, AI GFS: No graded forecasts yet.

Overall rank

Overall averages each forecast's rank on path and on wind strength. See the separate scores below.

Place on this list. 1 was closest to the weather that happened. A tie shares this number, and the next place skips ahead. Early read until the longer day count, then proven. The forecast source this row scores. Path and wind ranksOverall averages each forecast's rank on path and on wind strength. See the separate scores below. Track rankPlace on path miss. 1 was closest. On one storm this is that place. Across storms it is the average of those places. Each graded lead counts once. A tie shares the average place. Intensity rankPlace on wind miss. 1 was closest. On one storm this is that place. Across storms it is the average of those places. Each graded lead counts once. A tie shares the average place.
— GEFS mean Not enough forecasts yet — —
— GFS Not enough forecasts yet — —
— HAFS-A Not enough forecasts yet — —
— HAFS-B Not enough forecasts yet — —
— HMON Not enough forecasts yet — —
— HWRF Not enough forecasts yet — —
— NHC official Not enough forecasts yet — —

Track and intensity by model

Each row is one source at one lead that has already verified, including 12, 24, 36, and 48 hours. The count is how many forecasts shared a time with where the storm went. Path miss is statute miles. Wind miss is miles per hour. The rank number is that source's place in the table above, and it still uses 24, 48, 72, and 120 hours.

Place on this list. 1 was closest to the weather that happened. A tie shares this number, and the next place skips ahead. Early read until the longer day count, then proven. The forecast source this row scores. LeadHow many hours ahead this forecast was made. Scored leads are 24, 48, 72, and 120. The technical name is lead. CasesHow many past forecasts went into this average. A forecast counts only when the best track has a fix at that exact time. The technical name is cases. Track errorAverage how far the predicted storm path was from where it actually went, in miles. Lower is better. The technical name is track error. Track skillHow that path miss compares with the official hurricane forecast. Positive means better than the official forecast. Negative means worse. The technical name is track skill. Intensity errorAverage how far off the predicted wind speed was, in miles per hour. The file stores knots. Lower is better. The technical name is intensity error. Intensity skillHow that wind miss compares with the official hurricane forecast. Positive means better. Negative means worse. The technical name is intensity skill.
— Google DeepMind 12 h 2 57 mi Behind the official forecast by 48% 3 mph Beats the official forecast by 67%
— WeatherNext 3 12 h 2 35 mi Beats the official forecast by 8% 6 mph Beats the official forecast by 33%
— GFS 12 h 18 127 mi Behind the official forecast by 33% 5 mph Beats the official forecast by 5%
— GFS 24 h 16 223 mi Beats the official forecast by 25% 7 mph Beats the official forecast by 60%
— GFS 36 h 14 331 mi — 13 mph —
— GFS 48 h 12 358 mi — 16 mph —
— GFS 60 h 10 314 mi — 22 mph —
— GFS 72 h 8 256 mi — 26 mph —
— GFS 96 h 4 225 mi — 27 mph —
— UKMET 12 h 9 78 mi Behind the official forecast by 185% 6 mph Behind the official forecast by 50%
— UKMET 24 h 7 98 mi — 7 mph —
— UKMET 36 h 5 154 mi — 3 mph —
— UKMET 48 h 4 329 mi — 5 mph —
— UKMET 60 h 4 388 mi — 5 mph —
— UKMET 72 h 4 389 mi — 4 mph —
— UKMET 96 h 2 417 mi — 7 mph —
— Canadian GEM 12 h 9 116 mi Behind the official forecast by 109% 3 mph Beats the official forecast by 70%
— Canadian GEM 24 h 8 220 mi — 5 mph —
— Canadian GEM 36 h 7 285 mi — 6 mph —
— Canadian GEM 48 h 6 292 mi — 6 mph —
— Canadian GEM 60 h 5 310 mi — 11 mph —
— Canadian GEM 72 h 4 269 mi — 7 mph —
— Canadian GEM 96 h 2 219 mi — 9 mph —
— HAFS-A 12 h 18 111 mi Behind the official forecast by 23% 11 mph Ties the official forecast
— HAFS-A 24 h 16 172 mi Beats the official forecast by 18% 11 mph Behind the official forecast by 20%
— HAFS-A 36 h 13 275 mi — 17 mph —
— HAFS-A 48 h 11 297 mi — 19 mph —
— HAFS-A 60 h 8 288 mi — 17 mph —
— HAFS-A 72 h 7 219 mi — 19 mph —
— HAFS-A 96 h 3 241 mi — 28 mph —
— HAFS-B 12 h 18 109 mi Behind the official forecast by 25% 11 mph Beats the official forecast by 5%
— HAFS-B 24 h 16 178 mi Beats the official forecast by 76% 13 mph Behind the official forecast by 20%
— HAFS-B 36 h 13 279 mi — 14 mph —
— HAFS-B 48 h 11 392 mi — 22 mph —
— HAFS-B 60 h 8 336 mi — 23 mph —
— HAFS-B 72 h 6 272 mi — 25 mph —
— HAFS-B 96 h 4 239 mi — 21 mph —
— HWRF 12 h 7 55 mi Behind the official forecast by 5% 7 mph Beats the official forecast by 20%
— HWRF 24 h 6 129 mi Beats the official forecast by 8% 14 mph Beats the official forecast by 20%
— HWRF 36 h 5 278 mi — 14 mph —
— HWRF 48 h 5 329 mi — 19 mph —
— HWRF 60 h 5 314 mi — 26 mph —
— HWRF 72 h 5 277 mi — 32 mph —
— HWRF 96 h 4 260 mi — 22 mph —
— HMON 12 h 7 64 mi Beats the official forecast by 63% 8 mph Beats the official forecast by 13%
— HMON 24 h 6 83 mi Beats the official forecast by 76% 11 mph Behind the official forecast by 60%
— HMON 36 h 5 231 mi — 12 mph —
— HMON 48 h 5 267 mi — 13 mph —
— HMON 60 h 5 242 mi — 21 mph —
— HMON 72 h 5 221 mi — 23 mph —
— HMON 96 h 4 319 mi — 23 mph —
— NHC official 12 h 3 56 mi — 8 mph —
— NHC official 24 h 1 121 mi — 6 mph —
— GEFS mean 12 h 18 108 mi Behind the official forecast by 6% 3 mph Beats the official forecast by 20%
— NAVGEM 12 h 16 178 mi Behind the official forecast by 177% 6 mph Behind the official forecast by 7%
— GEFS mean 24 h 16 179 mi Beats the official forecast by 28% 6 mph Beats the official forecast by 80%
— NAVGEM 24 h 13 263 mi — 8 mph —
— GEFS mean 36 h 14 254 mi — 8 mph —
— NAVGEM 36 h 10 269 mi — 6 mph —
— GEFS mean 48 h 11 307 mi — 10 mph —
— NAVGEM 48 h 6 258 mi — 9 mph —
— GEFS mean 60 h 10 269 mi — 14 mph —
— NAVGEM 60 h 5 268 mi — 8 mph —
— GEFS mean 72 h 8 220 mi — 17 mph —
— NAVGEM 72 h 4 333 mi — 9 mph —
— GEFS mean 96 h 4 237 mi — 13 mph —

ECMWF AIFS, ECMWF HRES, ECMWF ENS mean, AI GFS: No graded forecasts yet.

Track map

The solid line is the best track. Dashed lines are official forecast tracks from a few advisories, from the issue position out through the leads stored in that advisory. Thinner lines are model tracks from NHC’s public a-deck for those same advisories, and only when that file actually contains them. Google DeepMind and WeatherNext 3 are ensemble-mean tracks from Weather Lab, drawn on those same advisories. ECMWF AIFS, ECMWF HRES, and the ECMWF ENS mean are open-data cyclone tracks, drawn the same way. AI GFS is NOAA’s AIGFS tracker, drawn when that file is still posted.

6°N 14°N 23°N 32°N 154°W 138°W 121°W 105°W
Map of Tropical Disturbance Julio. The best track, where the storm actually went, has 24 positions. 4 official forecast tracks are drawn. Model lines: GFS, GEFS mean, Canadian GEM, UKMET, HAFS-A, HAFS-B, HWRF, HMON, NAVGEM, Google DeepMind, WeatherNext 3. Latitude and longitude, scaled by the cosine of the mid-latitude so a degree of longitude is not stretched.
  • Actual track (24 positions)
  • NHC official Aug 24, 18:00 UTC
  • NHC official Aug 25, 00:00 UTC
  • NHC official Aug 25, 12:00 UTC
  • NHC official Aug 25, 18:00 UTC
  • GFS
  • GEFS mean
  • Canadian GEM
  • UKMET
  • HAFS-A
  • HAFS-B
  • HWRF
  • HMON
  • NAVGEM
  • Google DeepMind
  • WeatherNext 3

The chart measures how far the track was off in statute miles, the same miles as the home card. It includes 12, 24, 36, 48, 60, 72, 96, and 120 hours when a paired fix exists. The overall rank uses 24, 48, 72, and 120 hours. Positions are not interpolated.

How far the track was off

56 mi 12 h 121 mi 24 h
Average official track miss in miles by how far ahead. 12 hours 56 miles over 3 forecasts. 24 hours 121 miles over 1 forecast.
LeadHow many hours ahead this forecast was made. This map shows 12, 24, 36, 48, 60, 72, 96, and 120 when a paired fix exists. Overall rank uses 24, 48, 72, and 120. The technical name is lead. CasesHow many past forecasts went into this average. A forecast counts only when the best track has a fix at that exact time. The technical name is cases. Track errorAverage how far the predicted storm path was from where it actually went, in statute miles. Lower is better. The technical name is track error. Intensity errorAverage how far off the predicted wind speed was, in miles per hour, on this page. Lower is better. The file stores knots. The technical name is intensity error. Forecast max windAverage top wind in the official forecast, in miles per hour, on the paired cases. The file stores knots. The technical name is forecast maximum wind. Best-track windAverage top wind where the storm actually went, in miles per hour, at the same times. The file stores knots. The technical name is best-track wind.
12 h 3 56 mi 8 mph 44 mph 48 mph
24 h 1 121 mi 6 mph 40 mph 46 mph

Miles are statute miles. Wind is miles per hour. The National Hurricane Center file stores wind in knots. One knot is about 1.15 miles per hour. Nautical miles are in the technical details.

Top wind

12 h 24 h
Top wind, official forecast versus where the storm went. At 12 hours the forecast averaged 44 mph and where the storm actually went averaged 48 mph. At 24 hours the forecast averaged 40 mph and where the storm actually went averaged 46 mph.
  • Official forecast maximum wind
  • Best-track maximum wind

Source: National Hurricane Center / NOAA. The operational b-deck and the public a-deck are U.S. government works in the public domain. Google DeepMind and WeatherNext 3 ensemble means are experimental forecasts from Google DeepMind Weather Lab. Forecasts older than 48 hours are used under CC BY 4.0. ECMWF AIFS, ECMWF HRES, and ECMWF ENS tracks are ECMWF open data, used under CC BY 4.0. AI GFS tracks are a NOAA AIGFS product. Forecast Scoreboard is not affiliated with NHC, NOAA, Google, or ECMWF.