Here is a time-latitude plot of the air temperature measured over a north-south slice of Aotearoa/ NZ as it travelled through 2025.
MetBob. Bob McDavitt is the weather guru that uses //etBoB to provide meteorological information for cruising sailors, primarily for those in the South Pacific.
The land silhouette is provided to help relate the latitude axis to your place. It clearly shows temperature is cooler further south and during winter. This time section makes a “bar-code” graph which reveals the annual trend and the daily variation. It gives a rough indication of the extremes and provides a visual image for quick comparison with any another year to see seasonal variations.
Here below is what we had in 2024. Compared with 2024, 2025 was cooler with some blue getting to the far north in winter.
Looking at a similar diagram for the barometric air pressure provides a graph that combines all the daily weather maps into one image. This produces a more random looking barcode. The yellow and red lines correspond to passing HIGHS on the weather map, and the blues show the LOWS or depressions/storms. The scale is in Pascals, divide this by 100 to get hectoPascals/millibar.
This has more red in it than last year, with the months from April to August being mostly marked with passing Highs on the weather map.
The rain image below is probably the most interesting as it highlights the dry periods in Northland last February to April, wetness from May to October and dry from October to mid-December, then a wet Christmas/New year.
