Current    Charts    Radar/Satellite    History   30-day   90-day
Your observations   Warnings   Floods   WeatherLIVE
Sailing     Aviation     Farming     Astronomy     Walking
Weather School     Personal forecasts     Books by Simon
Contact us    Wxweb for business     Who's Who

>> Simon's Weather Musings <<

Best to stick with old faithful
Follow the jet in 7-10 days time

By Simon Keeling in Wombourne, Staffs 11:00hrs  17/1/2012
Temperature: -1.8C    Weather: Cloudy & frosty

Almost every day I show you the 7-10 day mean of the 500mb flow from the PSU ewall site. Many of you have asked questions about the charts, so here's a quick run down as to what they show (and today is a good example to use).

1. Solid black lines are the height of the 500mb standard pressure surface. This is about 18,000ft up.

2. The actual height 9in metres or feet) of the 500mb surface varies on a day to day basis, becoming lower down when the air is colder, higher when it is warmer; hence higher heights indicate warm air, lower heights, colder air.

3. Where the solid black lines are closer together, the winds are stronger.

4. Winds flow along the height lines.

5. 500mb is chosen because is gives a good indication as to where the jet stream is (black lines close together), and also nicely shows troughs (u-shapes in the black lines) and ridges (n-shapes in the clack lines).

6. The PSU Ewall charts also show height anomalies - red where air is warmer than normal, blue where it is colder than normal.

7. The chart of the left of the PSU chart is the ECMWF, the one on the right is the GFS operational.

Okay hopefully that helps? As far as today is concerned above normal heights are shown southwest of the UK, below normal to the northwest. The result of this (between next Tuesday and Friday 27th) is a weak jet stream indicated across the Atlantic and into the UK. Follow the black lines back and note they originate in the eastern States and Canada, so conditions are likely to be chilly.

But with a relatively weak jet stream conditions are likely to be fairly unsettled in Scotland, perhaps more settled further south.

Both models are in good agreement, so that builds confidence in the forecast. More on the video.

>> More of Simon's Weather Musings <<

5 Weather-Week things you need to know
By Simon Keeling in Wombourne, Staffs 08:00 01/09/2014
Quick fix of the weeks weather

5 Weekend Weather Facts you need to know
By Simon Keeling in Wombourne, Staffs 12:00 29/08/2014
A pleasant weekend ahead

Weather presents retailers sales chance
By Simon Keeling in Wombourne, Staffs 09:00 28/08/2014
The warmth of this weekend is being missed by many shops

[click here for a full list of Simon's Musings]

>> Garry's Notebook <<

Surfin\' USA
By Garry Nicholson in Darley Dale, Derbys 16:30 27/08/2014
Latest on Hurricanes Cristobal and Marie

Next Atlantic tropical storm developing
By Garry Nicholson in Darley Dale, Derbys 19:00 23/08/2014
USA & Pacific round-up

Heavy rain on way for Australia
By Garry Nicholson in Darley Dale, Derbys 18:20 15/08/2014
Snow and rough seas in New Zealand

[click here for a full list of Garry's Notebook's]

>> Captain Bob's Dispatches <<

Seasonal Outlook
By Captain Bob in Kingswinford 20:00 26/07/2014
Frosty mid October

Month Ahead
By Captain Bob in Kingswindford 20:00 26/07/2014
Mixed start but better later

Month Ahead
By Captain Bob in Kingswinford 18:00 12/07/2014
Turning more unsettled in August

[click here for a full list of Captain Bob's Dispatches]

>> Around the webcams <<
Latest webcam pics (add yours)

>> Learning channel <<
Cirrus over Cumulus - Rain ahead?

>> Forecast channel videos <<
Monday's Look Ahead - Do you believe in the high?
Saturdays Look Ahead 30/8/14
Fridays Look Ahead - Japanese Month Ahead
Thursdays Look Ahead
Tuesdays Look Ahead - CFS Update