Your daily forecasts from Boards.ie weather forum (NO CHAT)

Sunday, 3 May, 2020

Forecasts for Ireland


TRENDS for the week of 3 to 9 May, 2020

-- Temperatures will average close to normal values, possibly a bit above in some western and central counties.
-- Rainfall will average 25 to 50 per cent of normal values, generally rather dry, any higher amounts near south coast.
-- Sunshine will average near normal values.


FORECASTS

TODAY will be partly to mostly cloudy, with the slight chance of light showers in some parts of the south mainly. Highs 13 to 16 C.

TONIGHT will see some clear intervals further north, partly cloudy skies prevailing further south. Lows 2 to 7 C.

MONDAY will be rather cloudy also, with some brighter intervals, generally a dry day for most areas with a slight chance of showers towards late afternoon and then rain in the overnight hours for the south coast. Highs 14 to 17 C.

TUESDAY will see the occasional rain fragmenting to showers as it tends to pull away to the northwest, leaving behind a partly cloudy regime with highs 14 to 17 C.

WEDNESDAY and THURSDAY are looking rather similar too with partly cloudy skies and highs 14 to 17 C.

By FRIDAY into SATURDAY, some weak frontal systems are likely to be trying to bring a bit of rain but they have limited moisture and energy so it may be mostly a dry cloud with sprinkles of rain, with temperatures continuing in the normal range of about 14 to 17 C.

Nights through the week will likely be frost free in most places and average lows will be in the 5 to 10 C range.

There is still a strong chance of colder weather for some regions in the north and east by about SUNDAY 10th into the early part of the week following, and it still appears possible that this colder air will be held back from reaching some southern and western counties of Ireland so that the bland, near seasonal normals type of weather will continue for those regions. Where colder air does arrive it will drop the daytime temperatures a few degrees; a stronger change is likely for Britain with almost a wintry feel in some northern and eastern regions over that way. After a few days of this colder set-up it then looks rather unsettled with more frequent rain that may possibly become heavier than we've seen for some time now.

My local weather on Saturday was cloudy, rather warm and humid feeling with thundery buildups around but again no action locally, highs around 15 C. We got the work done on the upgrade of computer service here.

Tuesday, 5 May, 2020

Forecasts for Ireland


TRENDS for the week of 5 to 11 May, 2020

-- Temperatures will average near normal values; it will be slightly above normal to about Saturday then 1 to 3 deg below by Sunday onward.
-- Rainfall will average 25 to 50 per cent of normal values, the south may be somewhat favoured for the heavier amounts although no strong pattern is expected.
-- Sunshine will average near normal values.

FORECASTS

TODAY will be quite breezy (easterly 50 to 70 km/hr in many parts) with cloud near the south coast, and some risk of light rain at times there to early afternoon, but more sunny further north. The brisk winds will cool the east and south coasts with highs only 12 or 13 C there, while further inland near 15 C and possibly up to 17 C on the west coast.

TONIGHT will be clear except for some remnant cloud near south coast, and lows will be 4 to 7 C as the breeze will continue to some extent.

WEDNESDAY will see more cloud than sunshine in most areas and outbreaks of light rain, highs generally 13 to 16 C. There will be moderate southeast breezes.

THURSDAY and FRIDAY will be partly cloudy days with scattered outbreaks of light rain developing, a general trend for this rain to edge further north and then northeast over time, but not a very well-defined pattern, so a bit of a hit or miss situation with 3 to 7 mm rainfall potentials. Highs both days will be 15 to 18 C warmer well inland and towards north central counties in a southerly flow.

By SATURDAY this moisture will be driven back south by a developing cold front arriving later in the day in Ulster, but setting into motion a two-part cooling trend that will begin on Saturday with highs around 16 C south, 12 C north.

SUNDAY will be quite cool for time of year with brisk north to northeast winds and isolated showers, partly cloudy skies in general, and highs only around 10 to 13 C.

MONDAY and TUESDAY will continue cool but not as windy, with slight risks of frost developing for inland rural areas. Highs 12 to 15 C.

The longer-range outlook is then somewhat milder again as this cold outbreak modifies and repositions further east into central Europe, allowing high pressure to sink a bit to the south, so maximum temperatures would likely return to near normal values. Beyond that, a more unsettled theme emerges with potential for heavier rainfalls by second half of the month.

My local weather on Monday was cool but with the sun feeling quite warm, probably not much over 10 C in the shade, with a bit of a cool breeze.

Thursday, 7 May, 2020

Forecasts for Ireland


TRENDS for week of 7 to 13 May, 2020

-- Temperatures will average about 1 to 2 deg below normal values, starting a bit warmer than average now to Saturday, then turning about five degrees colder to reach 3 below average from Sunday on.
-- Rainfall will average only 25 per cent of normal, probably more now in the north than elsewhere, so a range from near zero in some places to perhaps half of normal at most.
-- Sunshine will average near or above normal values, as it will be quite sunny later in this interval after a more average start.


FORECASTS

TODAY most of the sporadic outbreaks of rain have moved through the south and west to mount a campaign further north, into Ulster where some amounts of 10 to 20 mm are possible. There will be some further outbreaks developing back in the somewhat moist air mass streaming in across the south, west and central counties but these will be more hit or miss. Some local thunderstorms are possible, and the east coast may remain largely dry with longer sunny intervals compared to most places which will tend to be mostly cloudy through the day. Highs will reach about 18 C except for some cooler coastal areas in light southerly breezes becoming moderate in sea breeze areas.

TONIGHT will see partial clearing and lows of 5 to 9 C with haze or mist widespread.

FRIDAY will likely be a more settled and warm day with showers more isolated, still more likely in Ulster than elsewhere. Highs 16 to 20 C.

SATURDAY will be partly cloudy and warm with an outbreak of blustery showers across the inland north, spreading south late in the day. Temperatures will fall sharply when this front passes but until it does, highs will be around 19 or 20 C.

SUNDAY will become breezy and much cooler as the front accelerates and moves through the south in the early morning, leaving in its wake a partly cloudy sometimes overcast and chilly flow from the north to northeast, with winds of 40 to 60 km/hr likely, temperatures falling by morning to 6 or 7 C and then making only a limited recovery in Ulster and Leinster, probably near 10 C there for daytime highs, but possibly up to 13 C in Connacht and Munster as well as some parts of inland south Leinster.

MONDAY will continue quite cool, with morning lows near 3 C, a slight risk of isolated frost, then partly cloudy to sunny by day and highs about 12 to 15 C.

TUESDAY to THURSDAY of next week will be a moderating period with the cool high moving down across Ireland and bringing more sunshine but with clear skies at night and lighter winds, the risk of some frosts in prone areas (mostly lower lying rural valleys). If you're in a town of any size or near the coast, you will probably avoid these frosts with lows near 2 C.

Once things warm back up to near average by Thursday (highs recovering to 16 to 18 C) there will be an increasing chance of cloud and rain spreading in from the southwest, and some hints of heavier rainfall developing eventually about two weeks from now.

My local weather on Wednesday was rather unpleasant with low cloud over the hills, occasional light rain and a chilly high of only 7 C. It was around 11 or 12 C in the nearby valleys. We have about 20% leaf foliation at our elevation but the trees are basically out in leaf down just a few hundred metres of elevation into the valley, so we will probably get there in a week to ten days. Muted celebration of a proposed return to limited normalcy in this part of the world, one pub says they may rename themselves the "I See You" as that's what it may resemble.

Saturday, 9 May, 2020

Forecasts for Ireland


TRENDS for week of 9 to 15 May

-- Temperatures will average about 2 deg below normal values (after a warmer than average day today).
-- Rainfall will average only 10 to 30 per cent of normal values, most or all of that later today into Sunday morning, then largely dry.
-- Sunshine will average 50 to 80 per cent above normal values.

FORECASTS

TODAY will be sunny, hazy and warm with scattered showers and isolated thunderstorms developing during the afternoon and forming perhaps a partial squall line moving south this evening. An update is likely around 2 to 3 p.m. Highs today 18 to 22 C.

TONIGHT the squally showers or thunderstorms will move rapidly south with some gusty winds from the northwest to north and partial clearing will follow, lows reaching 4 to 7 C (possibly 10 C in south west Munster).

SUNDAY any remnant showers will be moving well to the south of Ireland by mid-morning and most areas will be sunny to partly cloudy but considerably cooler in a rather brisk north to northeast wind. There could be some bands of showers hitting the southeast coast at times, and other bands affecting northwest Mayo and possibly parts of Ulster. But most places will hold dry and see highs of 10 to 13 C with winds north to northeast 40 to 60 km/hr.

MONDAY will continue partly cloudy to sunny, and rather breezy and cool, morning lows near 3 C and afternoon highs 11 to 14 C.

TUESDAY and WEDNESDAY could have isolated morning frosts, but daytimes will feel warmer in part due to a reduced wind speed, and highs reaching 14 to 17 C. Lows -1 to +4 C both days. Skies should be mostly sunny with cloudy intervals in east Ulster and north Leinster.

THURSDAY to the weekend of 16th-17th will see high pressure lingering and gradually moderating back to normal May temperatures.

My local weather on Friday was sunny and warmer than recent days, with a high near 20 C (25 to 28 C recorded in lower elevations). The colder air now over eastern Canada and the northeast U.S. has led to snowfalls over the inland northeast and New England overnight, will report on anything noteworthy in that update later today.

Sunday, 10 May, 2020

Forecasts for Ireland


Format today will be somewhat informal, trends are similar to yesterday's report and will return tomorrow.

The colder air is going to make its entry in two stages, with the southward push already underway, but a stronger impulse held up somewhat further north. This will create a renewed but weak frontal zone across south-central counties today as the full strength of the cold air will only be realized over the northern half of the country by mid-day. A zone of scattered showers is likely to develop in roughly the same areas as yesterday's thunderstorms, but only one or two of these might turn thundery. Skies will be partly to mostly cloudy north of this feature, and may remain sunny for part of the day along the south coast before the weak disturbance moves in there. Highs will reach about 12 or 13 C in the north, near 14 C around the frontal zone and 16 C on the south coast. Winds will become brisk northeasterly 40 to 60 km/hr at times after this feature moves through, but will be somewhat light and variable in the frontal zone for part of the day. About 2-5 mm of rain may fall in some places but a considerable portion of the country will have a dry day or just traces of rain.

Even tomorrow, the full extent of the colder push may not be fully realized as a weak secondary front will develop in the northeast flow as a reinforcement of the colder trend, and this will tend to push into Ireland overnight into Tuesday morning then dissipate as high pressure swells up over the northwest parts of the country. That will keep skies a little more cloudy on Monday with perhaps an even mix of sunshine and cloud, morning lows near 5 C and afternoon highs near 13 C, but once again it could be a bit warmer in parts of west Munster.

By Tuesday and Wednesday the high pressure will be more in control, skies should be clear at night and sunny in the daytime hours, which may lead to isolated frosts each morning, lows -1 to +4 C, with highs in the range of 13 to 17 C.

Weak troughs may erode this high at times later in the week, allowing some increase in cloud cover and isolated showers in eastern counties, but the theme will be similar with mostly sunny skies for other areas, and still some chance of isolated frosts. Highs will continue in the same range of 13 to 17 C.

By about Friday and Saturday, it looks as though warmer air will seep north again and while it stays partly cloudy and dry, temperatures will rise back to around 18 to 20 C.

Beyond that, a slight cooling trend is indicated with a weaker version of this week's evolution reloading during the following week, but that will not lead to a dry spell, but rather a more unsettled interval as Atlantic fronts try to push the weak high that forms away to the east.

My local weather on Saturday was sunny and very warm, the high around 24 C (some readings near 30 in lower elevations of B.C.), while in Ontario they were having record cold weather and highs only around 5 C with passing snow showers, and in some areas, accumulations of snow from lake effect snow streamers. This is quite unusual for May although in my research I notice that it was more common in the colder climate that existed in the 19th century. Toronto set a record low at the downtown recording site, the first one in May since 1923 (the absence of them mainly due to the growing urban heat island effect). There have only been about ten daily records set there since 1970 (most of them date back to the 19th century and early 20th century). The weather looks like it may remain very cool in eastern North America for the rest of this week with a rain-snow mix developing late today and early tomorrow across the lower Great Lakes region.

Tuesday, 12 May, 2020

Forecasts for Ireland


TRENDS for the week of 12 to 18 May, 2020

-- Temperatures will average 2 deg below normal, despite a slow warming trend back to more average values.
-- Rainfall will amount to 10 per cent of normal amounts on average and some places will see no rain at all.
-- Sunshine will vary from 25-50 per cent above normal in the south, to near normal amounts further north with more frequent cloud.


FORECASTS

TODAY will be generally sunny although some patchy cloud will be present in Ulster and some parts of Connacht and Leinster. Cool again with highs only reaching 12 to 14 C. Light winds will perhaps make it feel warmer than yesterday however.

TONIGHT will see more patchy frost, mostly in south-central counties, as cloud increases somewhat further north. Lows -1 to +4 C.

WEDNESDAY will be somewhat more cloudy especially for northern, central and some eastern counties with patchy light drizzle in a few northern locales; there should still be some decent sunny intervals for the south and west. Highs 12 to 15 C.

THURSDAY will be partly cloudy with isolated showers in the north, lows 2 to 5 C and highs 13 to 16 C.

FRIDAY will be partly cloudy and a little warmer with highs 14 to 17 C.

The WEEKEND is looking quite pleasant with some hazy sunshine both days, perhaps a little lower cloud and drizzle brushing the west coast at times, but generally dry, highs 17 to 21 C.

MONDAY and the first half of the following week should continue dry and warm except where light rain brushes outer west and northwest coastal areas. It then begins to look more unsettled past the 20th of May with some heavier rainfalls possible by about the 25th.

My local weather on Monday was sunny with a high near 19 C.

Planning to give a summer outlook later this week.

Thursday, 14 May, 2020

Forecasts for Ireland


Trends have not changed since yesterday and will return tomorrow -- the forecast will be brief so I can post the summer outlook and keep the total length similar.

TODAY will be sunny with cloudy intervals, some isolated showers developing over northern counties, highs 14 to 17 C.

FRIDAY will be partly cloudy with isolated showers, morning lows 1 to 4 C and afternoon highs 15 to 18 C.

SATURDAY will be hazy, partly cloudy to sunny and warmer, with highs near 19 C.

SUNDAY will become rather cloudy with light rain at times in west and north, highs near 18 C.

MONDAY and TUESDAY will be sunny and warm with highs 19 to 22 C.

From WEDNESDAY on, a more unsettled theme develops, with more frequent showers and temperatures back down around mid-teens.

Summer Outlook for 2020 -- In general, expect a near average summer with perhaps a slight bias to warmth, and near average amounts of rainfall. There will probably be a few warm to hot spells mixed in, but not dominating the entire season. It may be somewhat more unsettled in June and early July than later in the summer. Warmth may persist well into September as there is a signal for a warm autumn in general. For those who like thunderstorms, I think the chances are about average but would note that sometimes a near normal pattern is good for the production of one or two good events. So in summary, a bit of everything can be expected and no dominant theme, but as I like to offer forecasts in probability terms, I would add that there is a bigger chance of this "busting" towards warm/dry than cool/wet, so would set the odds at one in five for a cool, wet theme, about 50% for near average and 30% for warm/dry. That might also be a guide to the relative frequency of these different patterns during the summer ahead.

The highlight of the summer nights will be this year's conjunction of Jupiter and Saturn. By July and August, these planets will be prominent and visible most of the evening and middle hours of the night, and culminating in a close pass by the autumn. They are still somewhat distant (as we see them) in the morning skies at present, late June will be the earliest that you can expect to get a good view at a reasonable hour as they will appear a few minutes earlier each night. Another thing you're likely to notice is that full moons this summer will appear lower than we've seen them in recent years, as the lunar declination cycle of 18.6 years reaches maximum range in 2024. What that means is that the summer full moon will also be quite a bit south of the ecliptic plane (where the Sun would be in winter in the same part of the sky) and that means it appears even lower than the mid-winter sun, especially the early July full moon. Mark these dates on your calendar: July 4 and 5 -- the full moon will be seen near Jupiter and Saturn on either evening, probably a bit closer to them on the 5th as it moves past. This will be repeated just before the August full moon on 1st and 2nd, and a few days before the September full moon at the end of August. The close approaches of the Moon in late September and October will involve the waxing "half moon". I will research whether or not there might be occultation events where the Moon passes in front of each planet and let you know if these are going to be visible at the right times for viewing. Meanwhile Venus will very soon end its appearance as a prominent evening star as it drops out of sight in June and early July then begins to appear in the morning skies by late summer. Mars is going to become more visible in the autumn months, rising later than Jupiter and Saturn all summer. Mars will continue to edge further away from those planets and will be on its own in the midnight skies by October and November, starting to approach the familiar winter constellations of Taurus and Orion. It will pass fairly close to Aldebaran (a similar looking object) between Orion and the Pleiades by this coming December.

Saturday, 16 May, 2020

Forecasts for Ireland


TRENDS for the week of 16 to 22 May 2020

-- Temperatures will average near normal, perhaps slightly above in a few eastern counties.
-- Rainfall will average rather close to average for a change, even in the southeast eventually although it will hold dry longest (to mid-week).
-- Sunshine will average close to normal in some parts of the southeast but probably about 25 per cent below average elsewhere, to 50 per cent below normal in the north and west.


FORECASTS

TODAY will be mostly cloudy with a few brighter intervals in eastern and central counties. There will be scattered outbreaks of drizzle or very light rain mostly in Ulster and Connacht although some may extend a slight distance into north Leinster and west Munster. These will not produce very much rainfall today, trace to 2 mm amounts. Highs 14 to 17 C mildest in the inland southeast.

TONIGHT will become more overcast with the patchy light drizzle turning to a steady light rain for most of the west and north. The patchy light drizzle will then be encountered further east and into parts of the inland south. Lows 7 to 10 C.

SUNDAY will be dull and rather damp at best, with some steady rainfalls of 5-10 mm possible in the west and north. It could hold off most of the day in the southeast at least in Waterford, south Kilkenny, Carlow, Wexford and Wicklow. Highs once again 14 to 17 C.

MONDAY will start out similar to the weekend but there should be a slow improving trend as the cloud and moisture slowly give way to partly cloudy skies and the occasional longer sunny interval. Morning lows 7 to 10 C and afternoon highs 15 to 18 C.

TUESDAY looks rather variable for cloud cover but only scattered showers are likely and not very much accumulation expected. Some longer dry and possibly sunny intervals will persist in the south and east. Lows near 8 C and highs near 19 C.

WEDNESDAY will start out quite warm with scattered showers developing, some may become thundery and rather heavy by late in the day as a weak and disorganized frontal system slowly approaches. Lows near 11 C and highs near 21 C.

THURSDAY will see some further showery rainfalls and these will be slowly drifting further south and east perhaps bringing an end to the dry spell in the southeast. Total rainfalls in the mid-week interval should be in the 10 to 20 mm range in most regions. Highs near 18 C.

By next FRIDAY and SATURDAY a more settled regime will build in behind the slow-moving fronts and there could be longer intervals of sunshine then with highs near seasonal normals of 16 to 18 C.

The OUTLOOK beyond that is more unsettled with a chance of some more significant but not excessive rainfalls, at the most it should return to a normal amount of rain rather than going to the other extreme, at least for the foreseeable future.

My local weather on Friday was partly cloudy with occasional heavy showers mid-day and a warmish feel with highs around 18 C combined with rather high humidity. Our trees have come all the way to full if a bit tender leaf foliation now. There is still snow visible on the higher peaks (about 2000 metres elevation) nearby, but it has melted from the lower hills that reach 1600 metres elevation close to the town. Apparently the snow pack in the province was 25 to 50 per cent above normal values and it's melting fast this week so that flood watches are in place on many river systems; that is not a problem locally as we are on dry slopes here and no running creeks nearby, while the Columbia River in the nearby valley is extensively dammed and flood-controlled these days (it used to flood severely in some spring runoff events before those were built). The larger rivers in southern B.C. tend to peak in their runoff around late May into June. The worst flooding in modern times occurred in 1948 and before that in 1894.

Monday, 18 May, 2020

Forecasts for Ireland


TRENDS for the week of 18 to 24 May, 2020

-- Temperatures will average 1 to 2 deg above normal values (which at this point are around 17 C daytime, 7 C for overnight lows).
-- Rainfall may approach normal values although it now looks somewhat less likely so have revised this down to 75% of normal.
-- Sunshine will probably be fairly close to normal by the end of the week, even if it starts out rather cloudy.


FORECASTS

TODAY will be rather cloudy to start with a few lingering areas of drizzle or light rain, but there should be some improvements by mid-day and sunny breaks inland at least by afternoon, south coast could remain socked in with some low cloud and sea fog locally, and it will become rather warm and humid with highs reaching 18 to 20 C (except for a few coastal and far northern locations around 15 C).

TONIGHT will be misty and quite mild with patchy drizzle and lows near 12 C.

TUESDAY will have a mixture of cloud and sunshine, with quite warm conditions likely over most inland counties, highs 19 to 22 C. Some coastal areas could remain under more cloud, some mist or sea fog and highs closer to 16 C.

WEDNESDAY will also start out warm and dry with highs reaching 20 or 21 C then with increasing cloud a band of showers will cross the country from west to east by the evening hours, expect perhaps 5 mm of rain from that, with moderate southerly winds veering to southwest overnight.

THURSDAY will be a somewhat fresher day with scattered showers and highs near 18 C.

FRIDAY there is now model consensus on the close approach of low pressure from the central Atlantic bringing a spell of rather windy and wet weather, in particular to the Atlantic coastal counties. This won't be remnants of Tropical Storm Arthur but a separate low that forms about a thousand miles northeast of that storm mid-week, however, it does seem to take a lot of the energy away from Arthur which goes on to meander around west of Bermuda as a remnant depression. The low affecting Ireland will briefly become intense northeast of the Azores by Thursday but should be in a more moderate condition by the time it passes offshore from Mayo and Donegal on Friday morning. The results will be southwest winds of 70 to 110 km/hr and some heavy bands of showers with 10-15 mm potential for western parts of Ireland, more like 5-10 mm further east. Highs on Friday will reach about 15 C.

The OUTLOOK is for gradual improvement of these blustery conditions through Saturday, then another fairly warm and dry interval lasting for several days to be followed by a more active and gradually cooling regime towards the end of May.

My local weather on Sunday was very foggy much of the day, I would imagine in nearby valleys this fog was a low cloud ceiling at our elevation, and we had a few intervals of rather heavy rainfall too, with temperatures around 14 C. Tropical Storm Arthur has formed southeast of the Carolinas and is currently a weak tropical storm with maximum winds around 35-40 knots, expected to strengthen a bit by late today near Cape Hatteras, then will move slowly eastward, as I mentioned in the forecast for Friday, losing most of its energy to a distant low that forms well to the southeast of Newfoundland, while what's left of Arthur drops southeast then stalls west of Bermuda. It is becoming fairly common in recent years for a named storm in May, I think we've had them in maybe four of the past twelve years (even once in April). It's a combination of a longer season and a better ability to detect weak tropical storms. For whatever reason the season does not seem to be getting longer at the autumn into early winter end, in fact the November champion remains 1887 in that regard.

Wednesday, 20 May, 2020

Forecasts for Ireland


TRENDS for the week of 19 to 25 May, 2020

-- Temperatures will average 1 to 2 deg above normal values.
-- Rainfall will average 50 to 80 per cent of normal, the higher values in the west and north. Friday will account for much of this.
-- Sunshine will average near normal to 25 per cent above normal values.


FORECASTS

TODAY will be mostly sunny apart from some coastal fog, with cloud already beginning to spread into western counties slowly increasing later in the day. Quite warm in most areas with highs 20 to 23 C. Some coastal sea breezes and low cloud may hold temperatures closer to 15 C locally near south coast in particular, and 17-19 C on other coasts.

TONIGHT ... A weak band of showers will drift through the country reaching the east coast by about 0300h to 0600h, about 2 to 5 mm rain is likely if even that much, and the skies will clear rapidly once the front passes. Lows 10 to 13 C.

THURSDAY will remain largely dry after the early morning remnants of the weak front clear east, and with some sunshine it's likely to be just about as warm as the previous two days at perhaps 18 to 20 C. Winds will pick up to become moderate southerly by late afternoon. A band of heavy showers or longer intervals of rain will roll in by late evening and persist overnight into Friday morning, lows 11 to 14 C.

FRIDAY will become quite windy with some strong gusts near the Atlantic coasts, generally southwest 50 to 80 km/hr but locally 70 to 110 km/hr can be expected, with a total of about 10-20 mm of rain by Friday morning in all areas, possibly a bit more in parts of west Munster and Connemara. Then about 5 to 10 mm additional rain will occur mostly in western and later in northern counties from more localized bands of showers in blustery southwest winds, after the initial band moves through during the early morning hours, and there could be partial clearing later for the south and east. Highs falling back to around 16 C in the blustery Atlantic flow.

SATURDAY will see the after-effects of the passing low with moderate southwest winds and showers decreasing in coverage until skies become at least partly clear by late in the day, highs near 17 C.

SUNDAY and MONDAY of the following week will be sunny and warm with highs near 20 C on Sunday and 22 C on Monday.

OUTLOOK ... By Monday evening and overnight, another rather weak cold front will bring 3-5 mm rainfalls and then it will be a bit cooler for the next few days, with highs 16 to 18 C. Near the end of the week it may recover closer to 20 C, but stronger cold fronts are indicated for near the end of May into early June and a cooler northerly flow may drop temperatures below seasonal normals for a change.

My local weather on Tuesday was largely overcast, still rather warm, with slow-moving showers in the vicinity, looking like they were creating some heavy downpours a few miles away but just traces of rain fell locally, at about 18 C. Arthur is already "post tropical" and the other Atlantic low has taken away a considerable portion of its energy and begun to accelerate away to the northwest of the Azores. By about Friday 0600h this low will be around 250 miles west of Mayo then will end up near the Hebrides late Friday. What's left of Arthur will stay in the general area of Bermuda with a tendency to drift back to the south and southwest, eventually just dissipating completely.

Friday, 22 May, 2020

Forecasts for Ireland


TRENDS for the week of 22 to 28 May, 2020

-- Temperatures will average 1 to 2 deg above normal values.
-- Rainfall will average about 25 to 50 per cent of normal (with the qualifier that any rain that just fell today already is not part of that total, counting that more like 50 to 75 per cent).
-- Sunshine will average near normal values but it will tend to be somewhat reduced relative to normal further north.

FORECASTS

TODAY will be unseasonably windy especially in Connacht, some parts of Munster, and west Ulster, where strong gusts have been occurring for several hours and this will continue with a gradual easing by afternoon. Peak gusts so far include 120 km/hr at Newport. For most of the country winds in the range of 60 to 100 km/hr are likely, slightly stronger on exposed coasts and in hilly terrain. Some minor damage is likely but fortunately even stronger winds out to sea will remain out there (peak gusts to 140 km/hr may be encountered in the Atlantic marine areas). The skies will be largely overcast for most of the morning then a few breaks will appear, leading to some longer bright spells in the south and east. Some further rain is likely but there will be a lot of dry cloud scudding over with a few drizzle or light rain drops reaching the ground. For golfers, it's a four club wind, so bring the four wind club. Highs today near 17 C south and east, 14 C north and west.

TONIGHT will continue rather blustery with only a slight reduction in wind speeds to the 50-80 km/hr range in exposed areas, 30-60 km/hr inland. Skies will remain rather cloudy with passing showers in the west and north. Lows 9 to 12 C.

SATURDAY will be partly cloudy (to overcast in west and north) with some clearing late afternoon and evening when the persistent moderate southwest winds will drop off also, but most of the day will be rather gusty with winds in the 40 to 70 km/hr range. Highs 14 to 17 C.

SUNDAY will be partly cloudy to sunny from north to south, with only a slight risk of isolated showers in the north. Morning lows 6 to 9 C and afternoon highs 18 to 21 C.

MONDAY will be partly cloudy and warm with afternoon and evening showers or intervals of light rain, mostly affecting western and northern counties. This front will weaken later in the day moving inland and it could remain dry in parts of the southeast overnight as the remnants die out. Lows near 7 C and highs near 21 C.

TUESDAY will likely be a few degrees cooler in a partly cloudy westerly flow, but the temperature range will average the same as lows will be near 9 C and highs near 19 C.

WEDNESDAY will be partly cloudy with highs 18 to 21 C.

THURSDAY is currently looking a bit unsettled with a rather weak disturbance digging into the surface ridge and bringing a few showers along, highs 17 to 19 C.

The OUTLOOK beyond Thursday calls for a few more days of seasonably warm and dry weather around Friday-Saturday 29th-30th followed by a more unsettled and somewhat cooler interval where some colder air masses manage to get involved in a more variable pattern.

My local weather on Thursday was overcast with a few showers in the vicinity, not much rain actually fell and highs reached about 15 C. We have not seen much sunshine here all week. There are some heavier thunderstorms east of the Rockies near the U.S.-Canada border. I was just thinking today that storm chasing will be way down this season (the peak is approaching) and confined to people in their own vicinity but there will probably be some reports on weather forums.

Sunday, 24 May, 2020

Forecasts for Ireland


TRENDS for the week of 24 to 30 May, 2020

-- Temperatures will average 2 to 3 deg above normal values, with a warming trend through the interval.
-- Rainfall will average only about 10 per cent of normal values in the north, and near zero in the south.
-- Sunshine will average near normal in the north, to 25% above average in the south.


FORECASTS

TODAY will gradually brighten as cloud remaining over the north begins to break up slowly. Any lingering drizzle in Ulster or nearby north Leinster should end by mid-day at the latest. Highs near 15 C north and near west coast, with some mist or sea fog possible there. Warming to highs near 19 or 20 C in the inland south, central and eastern counties, near 17 C on the south coast.

TONIGHT will bring some clear skies in many areas, and lows 6 to 9 C. Mist and fog patches may form in some valleys.

MONDAY will start out sunny, and cloud will increase faster in the west and north than elsewhere, leading to sporadic outbreaks of light rain by late afternoon and evening, 1-4 mm expected in west and north, dry to 2 mm elsewhere and that mostly after dark. Highs 18 to 22 C.

TUESDAY will be rather cloudy at times in the north with patchy drizzle, hazy sunshine should return in the south if any cloud lingers from the weak front that will be turning around and drifting back north now as a warm front. Morning lows near 10 C and afternoon highs near 19 C.

WEDNESDAY will be hazy and warm, still with some risk of low cloud and drizzle in some northern counties. Highs generally 19 to 22 C, could be held down in the north or some coastal areas by low cloud or sea breezes locally.

THURSDAY to SUNDAY is looking quite warm now with the high pressure area swelling up right over Ireland and bringing ideal weather conditions with light winds, warm temperatures and considerable sunshine. Highs may reach values in the mid 20s in many areas and at least the high teens to low 20s near coasts too. This spell will break down somewhat beyond the end of the month and the first week of June (which starts on Monday 1st of June) but the warm, dry influence will be in the mix despite some weak frontal systems and plodding areas of low pressure trying to break down the block, the net result will probably be almost as warm and dry as this coming week but with some light rainfalls and temperatures a bit closer to normal values by then.

My local weather on Saturday was mostly cloudy with passing showers and a cool high of only 14 C. Seems like we are in phase because the forecast I just worked out for Ireland is very similar to the local forecast too in most details. We will also be seeing some early summer heat by late this coming week. This is a concern in the region because an above normal snowpack remains to be fully melted on higher terrain and rivers are generally running just below flood stage now.

Tuesday, 26 May, 2020

Forecasts for Ireland


TRENDS remain similar, 2-3 deg above normal, largely dry and with at least average sunshine if not a little more (south, east).

FORECASTS

TODAY will start out rather cloudy with some lingering mist or drizzle, but it should steadily improve in many areas with sunshine at times by mid-day and longer spells of sunshine by afternoon. This will warm temperatures up to around 19-22 C, with a few coastal areas that may stay cloudy also remaining closer to 17 C.

TONIGHT will be hazy and somewhat misty with mild lows of 8 to 12 C.

WEDNESDAY will bring hazy sunshine except for some low cloud and drizzle remaining near some northwestern coastal areas, generally quite warm with highs 19 to 23 C.

THURSDAY and FRIDAY will be very warm with at least some hazy sunshine despite a bit of cloud here and there, and a slight risk of isolated showers breaking out inland southwest. Lows near 12 C and highs 22 to 25 C, somewhat cooler in a few coastal areas.

The WEEKEND is looking somewhat cloudier with a slight chance of light rain in parts of the west and inland south, but still some sunny spells and relatively warm temperatures in the 20 to 23 C range.

OUTLOOK ... An easterly breeze may bring in slightly cooler air around Monday 1st of June, but temperatures are only expected to drop slightly and that mostly due to the stronger breeze bringing in cooler marine layers from the Irish Sea into Leinster. Western counties may not see much if any cooling, then this easterly will tend to die out as high pressure rebuilds, but it probably won't be quite as warm as this coming week, more like 19-22 C on average, still a bit above seasonal normals in many cases. Not much rain is likely to fall with these rather subtle changes, but if any does it would most likely be 1-3 mm amounts in some parts of the west and inland south.

My local weather on Monday was partly cloudy with passing showers and highs near 15 C.

Thursday, 28 May, 2020

Forecasts for Ireland


TRENDS for the week of 28 May to 3 June 2020

-- Temperatures will average 3 to 5 deg above normal values, with a slight cooling trend after a very warm start.
-- Rainfall will average 10 to 30 per cent of normal in scattered isolated showers, some places near southeast coast remaining dry.
-- Sunshine will average near normal values but cloud will be high based at times still allowing some filtered sunshine through.

FORECASTS

TODAY will be hazy and very warm, locally feeling hot, in a slight southeast flow. Ventilation may be a problem in warmer areas. Highs could reach 25 to 28 C except for somewhat cooler east and south coasts and in the far north, all of these areas closer to 20 C. Sunshine will be filtered through patchy but sometimes dense layers of higher cloud, but some places could get direct sun and this will lead to high sunburn potential (the more filtered sunshine has to be watched for this too, but you have a bit longer safe exposure using appropriate sunscreen).

TONIGHT will be quite a warm and still night with lows eventually dropping to 12 C but it will remain quite warm to midnight or beyond.

FRIDAY will be just about a carbon copy of today except that there could be isolated showers developing near the sea breeze boundaries inland from some coasts. Highs 24 to 28 C. Also the wind from the south-southeast will pick up slightly leading to stronger sea breezes that make a bit more penetration inland although would not count on much relief from this.

SATURDAY will be partly cloudy and very warm with isolated showers and thunderstorms again near sea breeze boundaries, lows near 14 C and highs near 25 C.

SUNDAY and MONDAY will become just slightly cooler with a bit more cloud around, more active shower or thunderstorm developments possible (inland west in particular), and highs near 22 C, but nights may remain just as warm (13-15 C).

The OUTLOOK has the main change in the forecast, a greater chance now of this warm and dry spell ending during next week instead of being delayed to end of that week. Here again, this may be just the latest in a never ending series of model "flip flops" as the computers struggle to assess when a nearly stationary and strong blocking pattern actually does break down, not always a strength of the models even in this day and age. Probably climatology gives just as reliable an indicator and these spells often last a week to ten days, not so often two or three weeks (as one did in June-July 1976 or perhaps in 1995 or 2006, but those were extraordinary for this climate). We should note also, our ancestors regarded summer as being 21st of June to 21st of September for a reason, whatever other periods we hear mentioned, the actual warmest 92 days of the year statistically is something like 14 June to 13 September. A warm spell breaking down this early in the summer or more properly late spring can get back to quite chilly readings that you wouldn't see in a mid-summer breakdown (at least not since the colder 19th century perhaps).

We also enjoyed a very warm day with perfectly clear skies for a while, now this evening higher cloud from the south has spread in and dimmed our view of stars and planets, but I expect that to burn off during the morning leading to an even warmer day than today's 25 C. Meanwhile, a second tropical storm formed briefly off the South Carolina coast and is moving inland now, quite unusual for two named storms to develop in May. Many think this will be a much more active season (the past few have produced some intense storms but overall have not been particularly active in terms of the storm count).

Saturday, 30 May, 2020

Forecasts for Ireland


TRENDS for the week of 30 May to 5 June 2020

-- Temperatures will average 2 to 3 deg above normal, with a gradual slide down towards normal near the end of the interval.
-- Rainfall may average 25 per cent of normal or slightly more in a few places, eventually; most of that will tend to come towards end of the interval too.
-- Sunshine will average near normal -- this is about the sunniest part of the year on average with 5 to 6 hours a day, which looks similar to what is expected with some variations. Some parts of the southeast get a bit more sunshine in July than in May, but otherwise May is the sunniest month of the year in most parts of Ireland.

FORECASTS

TODAY will be somewhat more cloudy than previous days but some hazy sunshine will occur at times, and it will stay very warm, with highs in the 22 to 26 C range except for a few cooler coastal locations. There is a slight chance of light shower activity near the west coast.

TONIGHT will be mainly clear and hazy with lows gradually dropping back to the 12-15 C range but the evening to at least midnight will remain very warm.

SUNDAY will bring a mixture of cloud and sunshine, with isolated showers possible in some western counties, highs 21 to 25 C.

MONDAY will be similar with the very gradual decrease in temperatures continuing, lows near 14 C and highs 20 to 24 C.

TUESDAY will be a transitional day between this warm spell and somewhat cooler air heading in from the north-northeast. It will be rather cloudy especially in the north with showers breaking out, more isolated or dry conditions in the south. Lows near 12 C and highs near 20 C.

WEDNESDAY will become partly cloudy with showers and a brisk northeast wind, considerably cooler with lows near 8 C and highs near 17 C.

THURSDAY will recover slightly ahead of a stronger cold air mass, partly cloudy to sunny with highs near 19 C.

From FRIDAY on, it may be quite cool but there will be times where it warms back up to the high teens. The average highs in the week following will be around 16 C. There will be some rain at times but no indications of any complete break in the drought (where applicable), just an easing of it perhaps would be the best description. I think it's inevitable if the temperatures stay at or below average for several weeks that some heavier rain would develop although it's no guarantee.

I don't have really old weather records at hand for Ireland, but the two driest Mays in the long UK history occurred in 1844 and 1896, this month looks like it will settle in between them as new second driest May for England and Wales (they missed most of that rain a week ago that is basically most of the rain Ireland has seen all month and so we've reached 40% of normal whereas in southern Britain it's more like ten percent. Anyway, the weather in both of those years in the past saw a gradual return to normal amounts of rainfall and neither summer was particularly hot, although in this climate I don't hold that up as much of a predictive sign. I think it does show that the most protracted spring dry spells are often followed by normal rainfall later in the season, and sometimes by quite cool weather conditions too.

My local weather on Friday was sunny and hot, the highs reached 27 C here and over 30 C in some nearby lower valley elevations. We are expecting this to break down into thundery and heavy rainfalls later Saturday and this has prompted flood warnings with snow melt nowhere near complete from the highest elevations yet.