Sunday, 18 October, 2020
Forecasts for Ireland
TRENDS for the week of 18 to 24 Oct 2020
-- Temperatures will average about 1.0 deg above normal, mostly due to very mild nights, daytime readings will not be unusually high for mid-October.
-- Rainfall will average 50 to 100 per cent above normal values, with local maxima of 150 per cent above (or 250 per cent of normal). Much of this rain is expected on Monday and Tuesday with flood risks rising.
-- Sunshine will be only 25 to 50 per cent of normal values.
TODAY will remain fairly dry although cloudy in most places with a few brief brighter intervals. Some pockets of moderate rain will graze the western coast of Connacht towards afternoon and evening, and elsewhere there could be isolated light showers. Moderate southeast breezes and highs 13 to 15 C.
TONIGHT will become wet in most of the south and west, and parts of Ulster, with 10-15 mm rainfalls in some of those areas, but it will be more of a drizzle in other areas, foggy at times with lows 7 to 10 C.
MONDAY will see rain becoming rather heavy and moving slowly through the midlands and southeast towards Leinster and east Ulster. Moderate east to southeast winds, highs near 13 C. Rainfalls 10-30 mm possible.
MONDAY NIGHT and TUESDAY a heavier rainfall is expected from a second low moving in on Monday night or early Tuesday, spreading 20-40 mm rainfalls through much of the country, with a risk of strong south to southwest winds on the south coast and spreading up the east coast, most likely between Cork and Wicklow (Dublin may or may not get into this windy regime briefly). The west and north of the country will have more moderate winds from east backing to northerly as the low tracks through the inland southeast. Rainfalls may be somewhat lower in parts of the northwest also. However, for many areas, significant flood risks may develop, monitor the relevant sources of flood information if you have concerns. Temperatures will be steady 12-14 C (near 10 C northwest).
By WEDNESDAY another low may develop closer to southwest England and place Ireland in a moist northeast flow for some of the day, then winds are likely to back to northwesterly and cooler air will arrive, temperatures falling to about 8-10 C, with potential for 10-20 mm further rainfalls.
THURSDAY should be a cooler day with northwest winds and passing showers or outbreaks of drizzle, winds 40 to 70 km/hr and lows near 5 C, highs near 9 C.
FRIDAY into early SATURDAY, a new disturbance from the Atlantic will push in with strong southwest winds and possibly more heavy rainfalls of 10-30 mm, temperatures rising to around 15 C.
The pattern after that storm passes looks very unsettled with most guidance developing a hurricane or strong low in the western Atlantic that will move towards Iceland during the last few days of October. The outcome for Ireland could be simply a mild spell without too much wind or rain, if the jet stream moves a bit to the north as some guidance suggests it will. But I wouldn't be too surprised given the energy shown by the jet all month if the actual outcome might be a strong wind event for coastal areas (some time after the 25th).
My local weather was overcast and cool with a high near 9 C, but we are into a gradual warming trend for the coming few days, so not much snow likely this week.
My winter forecast will be included in tomorrow's forecast package, the word "mild" does get a bit of a workout so be forewarned.