San Francisco's Heat Wave Forecast Defies Phone Apps

National Weather Service predicts record-breaking temperatures, but Google and Apple show milder forecasts.

Mar. 14, 2026 at 12:05am by Ben Kaplan

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The National Weather Service is forecasting a historic heat wave in California next week, with temperatures in San Francisco expected to reach the mid-80s or even near 90 degrees on Monday and Tuesday. However, weather forecasts from Google and Apple are showing much milder temperatures for the city during that time period, leading to confusion about the severity of the upcoming heat.

Why it matters

The discrepancy between official forecasts and the information provided by popular weather apps highlights the challenges of accurately predicting the weather, especially in microclimates like San Francisco. This can have implications for how residents prepare for and respond to extreme weather events.

The details

The National Weather Service's forecast discussion notes that an "unusually strong ridge" will bring "late summer-like weather" to the region, with the potential to break numerous daily and all-time high temperature records for March. The San Francisco Chronicle's forecast aligns with the Weather Service, calling for mid-80s temperatures on Monday and Tuesday. In contrast, Google's forecast shows a "lovely stretch of early spring time weather," while Apple's weather app indicates warmer but still not extremely hot temperatures. Meteorologists explain that the phone apps' forecasts are likely based on automated global models that struggle to capture the nuances of San Francisco's microclimate, which can be heavily influenced by factors like offshore wind direction and the marine layer.

  • On Monday, March 18, 2026, temperatures are expected to reach the mid-80s.
  • On Tuesday, March 19, 2026, temperatures are expected to reach the mid-80s or possibly approach 90 degrees.

The players

National Weather Service

The federal agency responsible for weather forecasting and issuing warnings about severe weather events.

San Francisco Chronicle

A major daily newspaper serving the San Francisco Bay Area.

Google

The technology company that provides weather forecasts through its various products and services.

Apple

The technology company that provides weather forecasts through its iOS Weather app.

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What they’re saying

“'An unusually strong ridge is bringing us late summer-like weather. ...This has the potential to break numerous daily high temperature records and even some all time high temperature records for March.'”

— National Weather Service (National Weather Service)

“We've covered peculiarities such as the marine layer and terrain differences that weather apps routinely miss in the notoriously tricky weather patterns of the Bay Area.”

— San Francisco Chronicle (San Francisco Chronicle)

What’s next

The National Weather Service and local meteorologists will continue to monitor the situation and provide updated forecasts as the heat wave approaches. Residents should closely follow official weather advisories and be prepared to take appropriate measures to stay safe during the extreme temperatures.

The takeaway

This discrepancy between official forecasts and popular weather apps highlights the challenges of accurately predicting the weather, especially in complex microclimates like San Francisco. It underscores the importance of relying on authoritative sources and professional meteorologists when preparing for extreme weather events.