① Daily card spending, captured through high-frequency datasets designed to monitor short-term consumption trends, varies substantially depending on both weather conditions and day of the week. Offline activities are limited by adverse weather conditions such as heat waves or heavy rainfall, resulting in a measurable reduction in consumption expenditure. Furthermore, since consumption patterns differ by day of the week, the impact of adverse weather also varies depending on when during the week these conditions occur.

This study examines the impact of weather on consumption by leveraging daily card spending data alongside temperature and precipitation variables while also explicitly considering interactions with the day of the week. Drawing on these analyses, we estimate the effects of major adverse weather events that have occurred this year on overall consumption.

② First, analysis of the relationship between weather and consumption revealed that (1) card spending declined by 7% during heat waves, 3% during cold waves, and 6% during periods of heavy rainfall—each a statistically significant reduction. These effects were most evident in offline activities, particularly in sectors such as offline shopping and dining out. In contrast, online shopping showed stable consumption patterns regardless of weather conditions. 

(2) Subsequent analysis of consumption patterns by day of the week revealed that total card spending was highest on Fridays. Offline consumption displayed a noticeable concentration on Saturdays compared to other weekdays. On weekdays (Monday through Friday), the share of online shopping was relatively high. Expenditures on automobiles, medical services, and education—which typically occur on business days—were also prominent on weekdays. 

(3) Furthermore, the interaction effect of weather deterioration on Fridays and Saturdays—when offline consumption is highest—was estimated. The results indicate that rainfall on these days led to a larger decline in card spending associated with offline consumption compared to other days of the week. When weather cleared following periods of restrained consumption due to rainfall, consumption rebounded to higher-than-usual levels—a phenomenon known as the pent-up effect. Meanwhile, the impact of heat and cold waves showed little variation across days of the week. This pattern appears to reflect heightened seasonal demand during summer and winter—such as vacations and purchases of cooling or heating equipment—which partially offsets the negative effects of extreme weather conditions. 

③ Building on these analyses, the impact of major weather events on consumer spending this year was estimated. Results indicate that cold waves during the first quarter and summer heat waves (June through August) contributed to a 0.18-percentage-point decline in annual consumption growth. However, below-average rainfall during the same period boosted consumption by approximately 0.09 percentage points. Consequently, the net impact of weather conditions on the private consumption growth rate for the year is estimated at approximately -0.09 percentage points.

④ This study provides valuable empirical evidence for the timely monitoring of consumer spending behavior using daily card spending and weather data. By quantifying temporary sources of variation in consumption, it is expected to enhance the accuracy of short-term consumption forecasts.