WET & WINDY WEEKEND AHEAD, KARL ADDS COMPLEXITY TO NEXT WEEK

Written by on September 22, 2016 in Rest of Europe, Summer 2016, United Kingdom & Ireland with 0 Comments

Today marks the autumn equinox when day and night are the same length. Beyond today, night will be longer than day and this becomes noticeable as warm air masses retreat and cold gains ground to the north.

Credit: Met Office

Credit: Met Office

With cold building and creeping southward, so the thermal gradient steps up, increasing the jet stream and therefore we say hello to the storm season once again.

Credit: BBC Weather

Credit: BBC Weather

However, warmth doesn’t give up too easily and when involving the tropics, unusually warm air can still get pretty far north still. We’re seeing this now and may see an even better example next week.

The weekend ahead is fairly straight forward, an Atlantic low pushing up towards Iceland will sweep it’s associated cold front east across Ireland and the British Isles. However, the slow eastward progression of this front may mean significant rain totals for western Scotland, perhaps into Cumbria, especially in upslope areas. Wind will also be a feature with gales or even severe gales on exposed western coasts.

Through the later half of Friday, the front departs Ireland and crosses the channel, making for a soggy, blustery end to the day in the west and through Saturday that front continues east. Sunday sees the front sink down over England with little rain left on it as it encounters the ridge. Blustery showers to follow behind.

[s2If current_user_can(access_s2member_level1)]

While it may feel like classic autumn weather in the cool, wet and windy west, further east it’s anything but with temps once again lifting into the low 20s in the hazy sun of eastern England.

Loading Maps...

Models suggest between 50-65mm over the next 72 hrs.

Credit: AccuWeather Pro

Credit: AccuWeather Pro

As for next week, Tropical Cyclone Karl drifts away from Bermuda and heads into the cooler, more hostile North Atlantic where it undergoes the routine transition into extra-tropical. When conditions are right, they can become stronger as a cold core system than a warm core, mature hurricane. Remember the Great Storm of ’87? These systems can maintain some of their tropical property and when baroclinicity is mixed with tropical, explosive re-cyclogenesis can occur.

Notice in the below GFS sea level pressure chart Karl and a developing low with a ridge of high pressure to the east, both Karl and the low may well merge  and lift the ridge to the east north with them.

Credit: chorleyweather.com

Credit: chorleyweather.com

Track is everything but it looks like the core of this system drifts WEST of Ireland up towards Iceland later next week and that would indicate the sub-tropical ridge and warmth lifts into the British Isles.

26 to 28C isn’t out of the question for Southeast England if that happens. However, the remnant low of Karl could become a major storm over the northeast Atlantic by next weekend producing storm-force winds close or over NW Scotland.

Warm Or Cold To Follow?

Interestingly the GFS pumps the ridge directly over the UK in the wake of the system rather than sending down a shot of autumn…

Credit: chorleyweather.com

Credit: chorleyweather.com

That’s followed by another low passing NORTHWEST of the UK and another ridge… The models have a tough time handling tropical heat distribution within the mid to high latitudes and so these solutions will change in the coming days.

Credit: chorleyweather.com

Credit: chorleyweather.com

 

It’s getting to that time! See this morning’s video.

[/s2If][s2If current_user_cannot(access_s2member_level1)][magicactionbox id=”18716″][/s2If]

Follow us

Connect with Mark Vogan on social media to get notified about new posts and for the latest weather updates.

Subscribe via RSS Feed Connect on YouTube

Leave a Reply

Top