Tuesday, 8 September, 2020
Forecasts for Ireland
TRENDS for the week of 8 to 14 Sept 2020
-- Temperatures will average 1 to 2 deg above normal.
-- Rainfall will average 50 to 75 per cent of normal.
-- Sunshine will average 75 per cent of normal but could reach closer to normal in a few parts of east and inland south.
TODAY will see the warm, humid regime continue with mostly cloudy skies but with a few brighter intervals, these more prevalent in the south and east, and also scattered outbreaks of light rain or drizzle more likely in the west and north (not much accumulation trace to 2 mm), and warm highs 19 to 22 C. It could reach 23 or 24 if any sustained sunny intervals were to develop anywhere, this air mass is actually capable of producing even higher temperatures but an inversion is keeping the potential warmth from mixing fully through the lower atmosphere.
TONIGHT a cold front will sweep through, there could be some brief heavy or squally showers, locally heavy rainfalls are possible although generally it will only be around 3 to 5 mm for most, then a fresher and less humid air mass will replace this current one, and temperatures will fall gradually to sunrise readings near 12 C. Winds will veer from southwest to west-northwest after midnight in the 40-60 km/hr range with some higher gusts possible especially over higher terrain near the Atlantic coasts.
WEDNESDAY will see cloudy skies gradually clearing through late morning and early afternoon and there could be clear skies at times by evening. Moderate west to northwest winds at times, highs 16 to 18 C. Fairly cool overnight with lows 3 to 6 C.
THURSDAY will be partly cloudy and warm with lows 3 to 6 C, and highs 17 to 21 C. Southwest winds will increase late in the day and rain will arrive.
FRIDAY will be cloudy with occasional light rain and somewhat cooler temperatures with highs around 16 C.
SATURDAY will be partly cloudy with isolated showers and highs near 18 C.
SUNDAY will be warm and humid with highs 19 to 22 C. Increasing cloud with rain at times in the west and north, becoming quite windy also.
MONDAY and possibly several following days will likely stay quite warm as the cold front pushing close to Ireland on Sunday evening may then ripple back north as a warm front and weaken, leaving Ireland in a warm southerly flow for several days ahead of slowly advancing frontal systems. Highs could be into the low 20s with isolated mid-20s.
This warm regime next week is likely to lead to a more active period but with rather unpredictable tropical systems on the move now (two new named storms in the southern and eastern Atlantic) their possible impact on eventual outcomes will be difficult for the models to work out (which is a nice way of saying they won't work it out, I suppose).
Now as to this tropical season which has just seen its 17th named storm ten days earlier than the previous record pace set in 2005, the eventual most active season with 28, it has to be noted that only five so far have been hurricanes which is not that impressive for any recent year let alone one with 17 named storms. And only one has been a major (Laura), which is no more than average for halfway through a season. The practice of naming storms includes omission of Q, U, X, Y and Z, so that after 21 storms we would reach the W name and then move on to the Greek alphabet as we did in 2005 (no other season made it that far, and the second most active year, 1933, was in an era before storms were named anyway, since naming began, 19 is second highest). The 2005 list was augmented after the year ended with an added storm called the "Azores hurricane" placed between Stan and Tammy. This year, we have reached the R storm (Rene) ten days earlier than 2005 produced Rita, but after our S storm, the T storm will be compared to the Azores hurricane for timing, and our V storm will be compared with Tammy of 2005. Then if we get to a W storm, that one will be compared to Vince of 2005, and if we need to use the Greek alphabet, the first storm (Alpha) will actually be comparable to Wilma of 2005 in terms of being the 22nd named storm. In late 2005 there were six more storms getting named from the Greek alphabet. I have to wonder if we will manage to equal that record, or what the plan is if they run out of Greek letters too.
My local weather on Monday (which was Labour Day here) was partly cloudy, breezy and considerably cooler at 18 C, and by this evening it was clear and calm with a frosty feel (granted we are up in the mountains here). All of this has led to the formation of a powerful storm system over Colorado which is rapidly developing tonight. There is already heavy wet snow in higher parts of Wyoming and this will spread into the Rockies of Colorado. It will likely be a cold rain around Denver but mixing with snow especially to the west of that city. Very strong northeast winds have caused numerous problems throughout the western U.S. and southern B.C. with power lines down in places, blowing dust closing highways, and any forest fires rapidly spreading. This regime has now spread into most of Nevada and Utah but heat-baked California will not get the colder northeast winds, instead this will lead to hot "Santa Ana" winds which is the last thing they need given the widespread forest and rangeland fires already underway there. I am fearful of a major disaster developing along the lines of the 2018 Paradise event somewhere with these stronger winds setting in. Not hearing much about wildfires in the Great Basin states or northern Arizona but if they have any those will also be accelerating with these winds (which have gusted to 100 km/hr in places).