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Fair Isle Weather - February 1999
A cold (-0.9°C), wet (163.0%) and windy month with
sunshine (102.3%) close to normal. The 13 days with snow cover at 0900 UTC equalled the
highest February (1979) total, but fell somewhat short of the 1981 December value of 18
days with snow lying.
The month began with high pressure centred close to
the southwest of the British Isles with a mild but showery SW airflow across Shetland. A
deep depression, tracking northeast across Iceland on the 2nd, moved on into
the Norwegian Sea on the 3rd bringing spells of heavy rain and very mild gale
force SW to Wly winds, with the months highest temperature occuring late in
the evening. Winds increased to storm force on the 4th, with gusts to 85 kt
Low pressure then became established across Scandinavia veering the gale force winds across Shetland from Wly to NNWly. The strong to gale force winds persisted for the next week, bringing cold Arctic air with heavy snow showers and drifting of the lying snow. High pressure, developing to the south of Iceland on the 8th, maintained the cold Nly winds for the next couple of days. As the high drifted south on the 10th, the winds backed Wly cutting off the supply of cold arctic air. The high then slipped away towards Portugal with mild SWlies becoming established across the north bringing a rapid thaw of the lying snow on the 11th. The thaw continued during the next few days as strong SWly winds brought further periods of rain and drizzle. A deep depression, tracking quickly east across Iceland into the Norwegian Sea on the 15th, brought cooler Wly winds to the north. As the low moved on into Scandinavia the strong to gale force winds veered NNWly on the 16th bringing colder air and heavy snow showers south across Shetland. Low pressure over Scandinavia maintained a strong to gale force Nly airflow with snow showers for the next few days. A developing Atlantic low, tracking north towards Iceland on the 18th, drove its associated fronts east across Scotland bringing strong to gale force SWly winds with rain and drizzle and a rapid thaw of the lying snow. This low then drifted southeast over the weekend, maintaining a strong W to NWly airflow across the area with frequent and occasionally heavy and thundery wintry showers. Low pressure, moving east into the Baltic, brought fresh to strong Nly winds and further wintry showers by the 22nd. High pressure then built across Shetland to give a brief settled spell. The high quickly declined on the 24th, as a developing low near Iceland pushed fronts east across Fair Isle on the 25th with strong SWly winds and spells of heavy rain and drizzle. The low became slow-moving in the Norwegian Sea, leaving Shetland in a bright and showery SW to Wly airflow to the end of the month.
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