- 0
Convergence lines
-
Latest Weather News
Fresher this weekend, but with thundery showers for northern and western areas
Low pressure close to the west brings fresher conditions off the Atlantic this weekend, but it will be windy, with thundery showers for northern and western areas. Continuing unsettled next week, with showers or longer spells of rain. Read the full update here
UK Storm and Severe Convective Forecast
UK Severe Convective & Storm Forecast - Issued 2022-06-25 08:19:26 Valid: 25/06/2022 0600 - 26/06/2022 0600 THUNDERSTORM WATCH - SAT 25 JUNE 2022 Click here for the full forecast
Turning cooler and windier over the weekend, with showers in the north and west
Another warm and humid day in the east, heavy thundery showers for northern England and Scotland. Turning cooler and fresher but windier over the weekend, as low pressure moves in close to the west, with showers in the north and west. Read the full update here
-
Our picks
-
Tour 5 - Day 2 Kansas Magic
Paul Sherman posted a topic in Storm Chase USA,
Tour 5 off to a flying start with an amazing tornado producing supercell in Kansas.
-
-
- 2 replies
-
-
Storm Chase - tour 4 day 9
Paul Sherman posted a topic in Storm Chase USA,
A mothership supercell and tennis ball sized hail - day 9 of tour 4 on the USA storm chase.-
-
- 0 replies
-
-
The colours of lightning
Thunderbolt_ posted a topic in Storms & Severe Weather,
The colours of lightning and what they can mean.-
-
- 37 replies
Picked By
Paul, -
-
Tour 4 - Day 2 (SD And Montana)
Paul Sherman posted a topic in Storm Chase USA,
A stunning supercell on Day 2 of tour 4 on the USA Storm Chase.
-
-
- 5 replies
-
-
Noctilucent Cloud season 2022
Arnie Pie posted a topic in Space, Science & nature,
The Noctilucent Cloud season for 2022 is underway.-
-
- 412 replies
Picked By
Paul, -
-
Question
Ben23
Hi all
Been lurking for a while but joined up to ask this question.
We've seen a lot of convergence lines on the surface pressure charts lately - culminating in 3 close together on the attached Met Office chart from yesterday. They are rarely marked at all on charts, and I'm guessing they're only being marked because they are potentially the most significant source of precipitation in the absence of any meaningful fronts.
The usual explanation of convergence lines I've found online tends to talk about onshore breezes in summer, acting in the opposite direction to the geostrophic wind. This forces air upwards, creating persistent cloud and, potentially, locally high precipitation. That's easy enough to understand.
But the recent convergence lines we've seen on the chart have all been parallel to isobars. The geostrophic wind implied by the pressure gradient would all be in one direction, so my question is, how can convergence lines form here? Where does the opposing wind come from? And how can you have 3 of them parallel to each other in such close proximity, which would imply 6 reversals of wind direction (3 of which must be against the pressure gradient) in the space of a couple of hundred miles?
Are they the remnants of fronts? Rolling air masses? What's actually going on to create them and make them persist?
Thanks
Link to comment
Share on other sites
Top Posters For This Question
1
Popular Days
Feb 9
1
Top Posters For This Question
Ben23 1 post
Popular Days
Feb 9 2021
1 post
Posted Images
0 answers to this question
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now