>
Worst of winter is over, but scenes like this may not be over just yet
VIEW FROM MY OFFICE LAST SUMMER: Warm days and lots of greenery and life to look forward to!Daytime temperatures are starting to reflect the stregthening February sun and the increase in hours of daylight, but there’s plenty more frosty nights and potentially cold days with still a decent likihood of more snow, the good news is, the worst of our winter is in our rear view mirror.
After a week or so worth of mild and sunny days and even a 4 consecutive day stretch in the 50s (F) under brilliant sunshine and a real hint at things to come, the dry air, light winds and clear skies, though warming us nicely by day is continuing to allow nights to still get well below freezing and thus producing hard to even severe frosts. The 5-10 degree above normal days are actually getting defeated by cold nights in the mid to low 20s which are making this month though, feeling pleasantly mild, still below normal… It also may surprise you how we’re still a little cooler than we could be for the month of February but that is simply down to the fact that our bodies have adjusted the the colder weather of the past couple ofmonths and therefore the still chilly days “feel” less cold.
Atlantic air having a greater push across Britain than back in December and early January when the Arctic air was too strong to penerate, this brings me to say that these two conflicting air sources leave us with a continued chance for more snow, even accummulating snow, not only for the rest of this month but even during March. I say that because of what’s happening across the world and the availability of the cold and where it’s stationed which is closer than one would like if they don’t want more chilly air or snow.
The cold and snow I had predicted for February does hold merit as the closing days of January and opening days of February did bring another two more rounds of snow with the second wave producing 2-3 inch accummulations and a repeat to travel snarling that had been experienced throughout the three-week cold blast. We also experienced yet another day which stayed at 32 degrees, making tat the 15th day for my site at or below freezing for the high. Most nights have dropped into the mid to low 20s despite mild to near warm late winter afternoons but thanks to dry air and clear calm skies, any warmth collected by day is rapidly released back to space once the sun drops below the horizon.
It’s been south of the border that has stayed colder and endured colder, east winds off the North Sea which has connected with Atlantic moisture to produce snows.
I expected the chillier air and snows to have impacted us more, but the very fact that other nearby areas of Britain have seen the cold and snow I had seen back in mid-January proves that the pattern that has brought us into the final month of meteorological winter was forecasted correctly and the fact that we’ve seen cold nights and snow to start and flurries mixed with rain throughout the month which is only half way there, means I am correct by as much as 70%.
I expected the chillier air and snows to have impacted us more, but the very fact that other nearby areas of Britain have seen the cold and snow I had seen back in mid-January proves that the pattern that has brought us into the final month of meteorological winter was forecasted correctly and the fact that we’ve seen cold nights and snow to start and flurries mixed with rain throughout the month which is only half way there, means I am correct by as much as 70%.
Atlantic or sub-tropical High’s beginning to heat up as the sun grows higher and stronger in the sky but they have a long way to go till their max in summer…. something to look forward to…
I still believe the rest of this month still has more winter in it. The big difference now that we’re into mid-Feb is when the suns rays reach earth’s surface and warms us to balmy late winter levels that make us think of spring, but days are still short enough and high pressure cells though warming still don’t have the ability or solar intensity to heat like they will a month from now. Therefore nights remain long enough to still get cold even under “mild” high pressure cells, the exact cells that bring us warm, dry weather in the heart of summer.
I still believe the rest of this month still has more winter in it. The big difference now that we’re into mid-Feb is when the suns rays reach earth’s surface and warms us to balmy late winter levels that make us think of spring, but days are still short enough and high pressure cells though warming still don’t have the ability or solar intensity to heat like they will a month from now. Therefore nights remain long enough to still get cold even under “mild” high pressure cells, the exact cells that bring us warm, dry weather in the heart of summer.
“northbound sub-tropical high pressure cells build north as the sun grows higher in the northern sky, but they also weaken once they get to a certain latitude where solar energy is still too low nearer the pole.
southbound arctic high pressure cells build south in late winter but weaken faster as the higher, stronger sun as well as less snow coverage on the ground, erodes their power more. Remember, the further south you go from the pole, the stronger the sun’s energy is. The reason why winter leaves earlier further south first…”
southbound arctic high pressure cells build south in late winter but weaken faster as the higher, stronger sun as well as less snow coverage on the ground, erodes their power more. Remember, the further south you go from the pole, the stronger the sun’s energy is. The reason why winter leaves earlier further south first…”
The Atlantic high (warm pools) is warming (because it’s from a sub-tropical source) as the sun grows higher in the sky each day we get closer and closer to spring but they haven’t the same energy that stops the dark of night and absense of sun from releasing all the warmth generated by day from bring released back to space at night and bringing still cold late winter nights that produce severe frosts and very chilly mornings.
But like in deep winter when the Arctic high pressure cell was in control, nights can only get truely cold and they certainly can still bring the most severe cold that can be generated during the deepest part of the winter in mid-February. There’s still enough darkness and such vast expanse of snow and ice for these cold air masses to still bring brutal conditions, they tend to weaken more at this point of the season as when these Arctic air massses drift south into the lower latitudes and away from the longer hours of darkness into longer hours of daylight, they weaken faster than they did when the sun was weak enough even down over Great Britain.
February can and does often bring the very worst weather but for us, it just so happens that we saw the true core of Arctic air strike us during the late December through early January period and makes these “Chilly” days of February seem warm.
February can and does often bring the very worst weather but for us, it just so happens that we saw the true core of Arctic air strike us during the late December through early January period and makes these “Chilly” days of February seem warm.
What I do believe is possible, is that are get another westward drift of Arctic air across the North Sea and into Scotland. England has seen Arctic air as well as the north of Scotland, but here is central lowland Scotland, we have enjoyed an Atlantic high pressure system which has brought, though cool nights and frost, days are warmer because the sun is now doing work it could not achieve during the earlier part of winter when the energy availible now was not present before.
During the mid-point or heart of winter, cold and snow is so expansive that is tougher to see mild air than cold. This winter saw such vast converage of snow and ice cover that this literally expanded the reservoir of cold, Arctic air, therefore dominating the playing field. But now that the days are growing longer and and and ice coverage is shrinking, this means Arctic air weakens when it doesn’t have the cold-air preservatives that snow brings, therefore you really need to be either in the Arctic regions or in the right place at the right time in order to see very cold conditions at the later of a winter season. This is because the vast ocean of Arctic air soon shrinks to become lakes and eventually puddle of cold Arctic air. Not enough cold air, means snow melts and once your snow melts, it’s tougher to get cold.
During the mid-point or heart of winter, cold and snow is so expansive that is tougher to see mild air than cold. This winter saw such vast converage of snow and ice cover that this literally expanded the reservoir of cold, Arctic air, therefore dominating the playing field. But now that the days are growing longer and and and ice coverage is shrinking, this means Arctic air weakens when it doesn’t have the cold-air preservatives that snow brings, therefore you really need to be either in the Arctic regions or in the right place at the right time in order to see very cold conditions at the later of a winter season. This is because the vast ocean of Arctic air soon shrinks to become lakes and eventually puddle of cold Arctic air. Not enough cold air, means snow melts and once your snow melts, it’s tougher to get cold.
Winter Weather not done with us yet…. Reason, there’s still too much cold and snow close by
The Arctic is still brutally cold and has still too much atmospheric dominance and coverage across the hemisphere to not still have influence on our weather, without many realising, a sneeky stream of Arctic air across the North Sea and into the north-central Highlands of Scotland and across portions of England has constantly been altering eastward moving Atlantic sourced moisture into Britain and colliding with eastward streaming Arctic air and has been producing snowfall, albeit generally light for the most part and also generally at slightly higher levels but it’s presence has never fully left us, now and again, it’s presence has been made clearer with snowfalls down at low levels.
The Arctic is still brutally cold and has still too much atmospheric dominance and coverage across the hemisphere to not still have influence on our weather, without many realising, a sneeky stream of Arctic air across the North Sea and into the north-central Highlands of Scotland and across portions of England has constantly been altering eastward moving Atlantic sourced moisture into Britain and colliding with eastward streaming Arctic air and has been producing snowfall, albeit generally light for the most part and also generally at slightly higher levels but it’s presence has never fully left us, now and again, it’s presence has been made clearer with snowfalls down at low levels.
Our best chance at seeing more days that fail to hit the freezing mark is when cold lowlying air can get in and clouds remain overhead. But even when the Arctic air is in place and the sun is shining, the sun is simply becoming too strong and tends to warm even cold air at these farther south latitudes than perhaps further north in northern Scandinavia where the sun angle is still weak enough that it doesn’t have the ability to warm the surface as much.
More snow and cold is still very possible.
The pattern is likely to grow ever more dominated by milder Atlantic weather as the Arctic air and snow and ice shrinkage is forcing the retreat of Arctic air, HOWEVER The vast pool of Arctic air is still very large and dominant across much of Europe, parts of Asia and most of North America, combine this with forecasts of negative AO and NAO’s throughout late February and March (the very upper air signals that produced such cold in Dec and Jan) means more snow and cold is on the cards, the difference will be the late season version which means we don’t see the same depth of cold nor longivity of the cold pattern. There’s too much solar energy now.
Therefore a continuation of chillier air getting shipped across the North Sea and into the UK is still more likely than not and this air albeit is nowhere near as cold as earlier in the season, will still have a higher than normal chance at meeting moist Atlantic air and could still bring us a chance of sticking snow. Push cold air across perhaps a short lived snow cover (24-28 hours) and we can squeeze out another sub-freezing day or two and another 1-2 nights that plummet into the teens.
Therefore a continuation of chillier air getting shipped across the North Sea and into the UK is still more likely than not and this air albeit is nowhere near as cold as earlier in the season, will still have a higher than normal chance at meeting moist Atlantic air and could still bring us a chance of sticking snow. Push cold air across perhaps a short lived snow cover (24-28 hours) and we can squeeze out another sub-freezing day or two and another 1-2 nights that plummet into the teens.
Frigid nights are still possible if snow is covering the ground and Arctic air is in control. Cold rather than frigid nights are the more likely bet which usually constitutes in my mind lows, clear, calm nights and absence of snow on the ground with lows falling into the low 20s like we’ve seen over recent nights. These cold nights only start to become less cold when nights become ever shorter which aren’t usually until late March, I say, because even nights well into March can hit levels of 20 below normal. 18-20 degree nights aren’t out of the question until around March 15th but snow cover is really when those cold levels can be achieved at this late point in the winter season.
Mark Vogan’s Cold Weather Glossary:
Mark’s definition of differing a Cold night from a Frigid night?
Frigid night: 15 degrees or less and usually with snow on the ground. (15-20 is Very Cold)
Cold night: between 20-25 degrees,
Cool night: between 25-32 degrees.
Frigid nights rarer here and are usually always with snow on the ground, cold nights are more common and occur at more times throughout winter and are achievable without snowcover…
This scale can be adjusted however with time of year. For example. A night in the low 20s in April could be considered frigid and a night in May in the upper 20s could be considered “cold”… This is because as one heads further away from the coldest part of winter, the colder the temperature, the later in winter, will mean the greater departure from normal…
This scale can be adjusted however with time of year. For example. A night in the low 20s in April could be considered frigid and a night in May in the upper 20s could be considered “cold”… This is because as one heads further away from the coldest part of winter, the colder the temperature, the later in winter, will mean the greater departure from normal…
Days can still be cold but what may have produced a high of 25 in early January may produce a high of 35 degrees simply because the energy released to the ground is much stronger, more direct and is present for a longer part of the day therefore it’s tougher to sustain colder highs.
With snow and a cold high, we may still see highs which only warm to around 35 degrees and nights that are still long enough and snow cover which is a great reflectant and can force daytime warmth back to space and bring very cold nights still, even well into March.
With snow and a cold high, we may still see highs which only warm to around 35 degrees and nights that are still long enough and snow cover which is a great reflectant and can force daytime warmth back to space and bring very cold nights still, even well into March.
More snow and more chilly days and cold nights is still expected, but we are simply not going to see sustained cold but more in-out blasts with inbetween mild periods.
Over the next few days we appear to have a greater chance at seeing some flurry action, perhaps even a dusting with below freezing nights. Baring in mind that the average high is pushing the mid-40s and lows are now into the mid-30s. I wouldn’t be surprised if we managed to squeeze out another day or two with highs barely topping freezing and some nights in the next 2-3 weeks which bottom out in the 18-22 degree range…
I do expect our first 60 degree high during the month of March and I am beginning to look at what our summer may have in store…
I shall be releasing a preliminary summer forecast on March 31st, so hang in there..
Thanks for reading.
-Mark
Email me at [email protected]
Recent Comments