Unseasonal warmth but watch for ‘haar’, says Wick weather watcher
Caithness basked in “unseasonal warmth” for the time of the year yesterday (September 17), says a local weather pundit.
In Wick, lengthy sunny periods coupled with a pleasant force 3 south-south-westerly breeze lifted the mercury to a remarkable 22.3C (72.1F) just after 4pm, reports weather columnist Keith Banks.
“The 'Foehn effect' was responsible for the exceptional warmth experienced in Wick and other favoured locations in the east of the county on Tuesday. The average maximum temperature for the town in September is 14.7C (58.5F).”
He says that, in comparison, the highest temperature recorded in Wick last Tuesday was a “decidedly cool” 11.0C (51.8F).
“The current spell of fine weather is the result of a large area of high pressure that developed over the British Isles on Monday. Subsequently, this feature continued to build as it drifted eastwards to be over the southern North Sea, deflecting the disturbed weather associated with the jet stream far to the west and north of Scotland.
“Consequently, a very broad south-to-south-westerly airflow has become established and this has gradually sourced increasingly warm air from the Azores and Iberia.
“The current spell of summery weather will continue on Wednesday, with cloud cover dissipating to give prolonged sunshine during the day. However, with the wind likely to back into the south-south-east, Wick and other locations on the east coast, will be less favoured for the best weather because the risk of 'haar' or low status will increase.
“Therefore, temperatures are likely to be significantly cooler than Tuesday, perhaps peaking at a more modest but still warm 18C-19C.”
He says that hot spots on Wednesday are likely to be Thurso, Halkirk, and inland locations such as Kinbrace where the temperatures could reach highs of 22C-24C.
“Thereafter, temperatures will return to values close to the seasonal average.
“This corresponds with the likelihood of low cloud or 'haar' increasing as the high relocates to north of the British Isles, allowing an easterly airflow to become established. Nevertheless, it will remain dry.”
