SF July 7 High Temp: Can 64-65°F Hold at Forty Percent?

San Francisco’s July weather follows one of the most predictable patterns in American meteorology. The marine layer rolls in from the Pacific, Karl the Fog suppresses afternoon heating, and downtown highs cluster in a narrow band between 62 and 66 degrees Fahrenheit almost every July week. The 64-65°F outcome currently holds a 39.5% implied probability in this multi-outcome market, making it the leading single bracket by a meaningful margin. That is not a commanding lead, but it reflects where the climatological center of gravity sits for this city in early July.

This market asks: what will San Francisco’s highest temperature be on July 7, 2026? The 64-65°F bracket trades at $0.40 YES and $0.61 NO. Resolution closes at noon on July 7. Total volume stands at $13,527, with $13,547 traded in the last 24 hours, suggesting nearly all activity is very recent.

How the 64-65°F Contract Works

The contract resolves YES if San Francisco’s official high temperature on July 7 falls between 64°F and 65°F inclusive. The National Weather Service measures the official daily high at its designated observation point for San Francisco. If the recorded high lands anywhere outside that two-degree window, the contract resolves NO regardless of how close the reading comes.

• YES ($0.40, 39.5% implied): San Francisco’s official high on July 7 lands at exactly 64°F or 65°F.
• NO ($0.61, 60.5% implied): The high falls in any other bracket: warmer, cooler, or adjacent ranges like 62-63°F or 66-67°F.

The NO side wins whenever the high drifts into any neighboring bracket. San Francisco’s marine layer is famously variable. A stronger onshore flow pushes the high into the 60-63°F range. A weaker or delayed fog pattern lets afternoon sun push readings toward 66-68°F. Either scenario pays NO, and both are plausible on any given July day. The 60.5% NO probability reflects exactly that spread-across-brackets risk.

Sponsored Partner

Momentum and Market Signals

The momentum composite here is flat. The one-hour price change is 0.0%, and the trend score sits at 40.51, which is below the midpoint of a neutral range. The sharp price drop of roughly 15% on July 5 drove this market from its opening level down to its current position. That move likely tracked an updated NWS forecast that nudged expected highs slightly, redistributing probability across adjacent brackets.

Total volume is $13,527, with nearly identical 24-hour volume of $13,547. That slight discrepancy reflects rounding, but the practical signal is clear: this market opened and filled almost entirely in a very short window. Liquidity sits at $44,479, which is healthy relative to the volume traded. Because total volume falls well below $1 million, any single meaningful forecast revision or last-minute weather update could move the price sharply before resolution.

• The one-hour and 24-hour price changes are both effectively flat, confirming the market is in a holding pattern ahead of the July 7 observation window.
• The July 5 price drop from $0.50 to the current $0.40 level is the dominant recent signal, reflecting downward revision in the probability of a 64-65°F outcome specifically.
• Liquidity at $44,479 is robust for a short-duration weather market, but thin overall volume means a credible forecast update could move YES price by several cents quickly.
• Trader sentiment leans bearish on this bracket: 60.5% of implied probability sits on NO, spread across ten competing temperature ranges.

Lines Analysis: Where the Forecast and the Market Agree

The National Weather Service’s July climatology for San Francisco places the median daily high in the 63-65°F range during the first two weeks of July. The 64-65°F bracket sits squarely in that median zone. When no anomalous pressure system disrupts the standard marine layer pattern, this bracket is simply where SF days land most often. The market’s 39.5% probability is reasonable given that it represents one two-degree slice of a ten-outcome distribution.

The risk to this bracket runs in both directions, but the downside case has a clear mechanism. A stronger-than-expected marine layer, which the NWS Bay Area office monitors through coastal buoy data and upper-level wind analysis, pushes afternoon highs into the 60-63°F range. San Francisco recorded highs below 62°F on multiple July days in recent years when fog persisted through the afternoon. That scenario dissolves this bracket’s value entirely. A warming scenario, where a weak thermal trough over the Central Valley draws warmer air into the Bay, could lift the high toward 67-70°F. Both tails have real probability mass.

Signals to Monitor

• The NWS Bay Area zone forecast for San Francisco through July 7 is the single most important input. Any revision toward cooler or warmer expected highs directly reprices this bracket.
• Coastal buoy sea surface temperatures off the Farallon Islands indicate marine layer strength. Cooler SSTs strengthen the fog machine and push highs down.
• 500-millibar ridge amplitude over the eastern Pacific determines how much the marine layer weakens. A stronger ridge equals warmer SF afternoons.
• The morning marine layer burn-off timing on July 7 itself will determine the actual high. Fog clearing before noon typically produces highs in the 64-67°F range.

At $13,527 in total volume, this market reflects genuine forecast uncertainty distributed across ten outcome brackets. The data favors the 64-65°F bracket as the single most likely outcome, but in a ten-way split, 39.5% still means this bracket misses more than six times out of ten. The adjacent 62-63°F and 66-67°F brackets each hold meaningful probability mass that collectively exceeds the leading bracket.

LINES VERDICT

Climatological Leader, Crowded Field

The 64-65°F bracket sits at the statistical center of San Francisco’s July temperature distribution. The marine layer makes any two-degree window genuinely uncertain, and the price drop on July 5 suggests the forecast already moved slightly against this bracket.

What the market says: At 39.5% implied probability, the market judges this the single most likely outcome in a ten-way field. With resolution arriving in less than 48 hours from this writing date, any forecast shift will reprice this contract fast.

Key unknown: The NWS Bay Area afternoon forecast update for July 7 is the decisive input. A revision of even two degrees in expected high temperature shifts probability mass into an adjacent bracket and could move the YES price by a meaningful margin before markets close.