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Where the models disagree today

Sunday's widest spread is in Boston, where seven models put the high anywhere from 48° to 59° in two camps; every city's spread is on the map, and the day's written read follows it.

How this page is built

Every number here is computed from The Spread's own archive of what each model actually published, run by run. The written discussion narrates those numbers and is not allowed to add any — no fronts, no systems, no forecast. It describes what the models are doing, which is what this archive measures.

Sample is 26 archived US cities, so "everywhere" means those cities. The map draws markers only: interpolating between them would show a pattern nobody measured.

26 archived cities · daily high temperature · day 3 (2026-10-18) · guidance as of 2026-10-15T12:51Z

Where they're fighting

One marker per archived city, labelled with its coolest and warmest model forecast for day 3; bigger and deeper in colour is a wider spread, and a dashed ring means three or more camps.

Reading the map

Each marker is one archived city, placed geographically. The label gives the coolest and warmest model forecast for day 3 — so a wide pair is a city the models disagree about — and marker size and colour are the spread between them. The coastline, lakes and state lines are there to place them; no value is drawn between the cities, because we know these 26 points and not the country between them.

A dashed ring means the models fractured into three or more distinct camps there — not just a wide range, but several competing answers at once. Most cities carry two camps at this lead; these are the ones telling more stories than that.

On a phone the map is drawn at the screen's width and names only the five widest; the list under it has every city.

Seattle 54–59° Minneapolis 59–67° Minneapolis Boston 48–59° Boston Buffalo 56–59° New York 53–61° New York Chicago 57–63° Philadelphia 55–61° San Francisco 62–73° San Francisco Washington 57–62° Denver 69–71° St. Louis 62–69° Los Angeles 84–91° Charlotte 59–63° Oklahoma City 58–65° San Diego 83–91° San Diego Phoenix 81–86° Atlanta 61–66° Dallas 66–72° New Orleans 68–71° Houston 69–75° San Antonio 68–75° Orlando 72–80° Tampa 74–82° Miami 79–82°

The widest spreads

  1. Boston48–59°11° spreadtwo camps
  2. San Francisco62–73°11° spreadtwo camps
  3. Minneapolis59–67°8° spread
  4. San Diego83–91°8° spread
  5. New York53–61°8° spread
  6. Orlando72–80°8° spreadtwo camps
  7. Tampa74–82°8° spreadtwo camps
  8. Salt Lake City64–71°7° spread
All 26 cities
  1. St. Louis62–69°7° spreadtwo camps
  2. Los Angeles84–91°7° spread
  3. San Antonio68–75°7° spread
  4. Oklahoma City58–65°7° spreadtwo camps
  5. Detroit56–63°7° spreadtwo camps
  6. Chicago57–63°6° spreadtwo camps
  7. Dallas66–72°6° spread
  8. Philadelphia55–61°6° spread
  9. Houston69–75°6° spread
  10. Phoenix81–86°5° spread
  11. Seattle54–59°5° spread
  12. Washington57–62°5° spread
  13. Atlanta61–66°5° spread
  14. Charlotte59–63°4° spread
  15. Buffalo56–59°3° spread
  16. New Orleans68–71°3° spread
  17. Miami79–82°3° spreadtwo camps
  18. Denver69–71°2° spread

These are day 3. For today's spread in each of these cities, see every location we archive.

Today's discussion

Boston is where the models disagree most about Sunday. Seven forecast models put the city's high anywhere from 48 to 59, and they split into two separate camps. The European ECMWF model is coolest at 48. The warmest, at 59, is NOAA's AI version of the American GFS, called AIGFS. Their maps put an area of high pressure in very different places. ECMWF has it about 40 miles northeast of Boston, near Salem, Massachusetts, at 1035 hPa. AIGFS puts it about 370 miles southwest, near Annapolis, Maryland, moving east. ECMWF's colder number appears tied to placing that high right beside the city.

San Francisco is close behind, at 62 to 73, also split into two camps. The American GFS is coolest at 62, and its map has an area of low pressure about 240 miles north, near Mt. Shasta, California. The Canadian GEM model draws no such low, and its high is 66. GFS's cooler forecast looks tied to that low. Minneapolis runs from 59 to 67. GEM is coolest there and puts an area of low pressure about 720 miles west-southwest, near Colorado Springs, Colorado. GFS is warmest and places its version only about 360 miles away, near Pierre, South Dakota.

Across the 26 cities tracked, most disagreements are smaller. Denver is the tightest, with every model between 69 and 71. When the models agree that closely, a forecast three days out deserves more trust. When they split into camps, as in Boston, treat any single number as a guess within a range. Plenty is still shifting, with 104 changes recorded across all 26 cities in the past day. The way the models grouped changed in the same way across Minneapolis, St. Louis, Chicago, Detroit, Buffalo, Philadelphia, New York and Boston, and again across Tampa, Orlando and Miami.

The models also have habits worth knowing. GFS runs about a degree warm on average and has come in at least 3 degrees above the middle forecast 14 times, never below it. GEM leans the other way, running cool 15 times.

Issued 2026-10-15T12:53Z from 26 cities' archived model runs. Written from the numbers on this page — no forecast of its own.

Maps that draw every model

Unique maps which illustrate the spread: each one draws multiple models at once. All 24 maps

Which models run warm

How far each model's highs sit from the median of all of them, averaged over every archived city and lead; positive runs warm. This is not accuracy: the median can be wrong too. Warm and Cool count model-days at least 3° off the median, out of 52 to 78 each. Consensus products are left out — they are averages of the rows below, not competitors.

Modelvs median WarmCool Model-days
GFS +1.13° 14 0 78
ICON -0.09° 1 1 52
UKMO -0.09° 4 4 52
AIFS -0.11° 6 7 78
ECMWF -0.22° 7 11 78
AIGFS -0.27° 7 11 78
GEM -0.83° 3 15 78