Over the last couple of days I’ve been keeping a close eye on the weather forecast models because there are indications that suggest we could see some wintry showers along the Eastern side of the country sometime between the 12-18th October.

Todays 06z GFS shows the possibly wintry spell along the East slightly earlier, around the 13-15th. Although high pressure is still being forecasted too close to the UK so the -5c @ 850hPa just gets pushed to the East of us, and with high pressure that close the chance of precipitation is decreased anyway.

Still time for things to change, I haven’t given up hope that we could see some wintry showers down the Eastern side of the country. Although at the moment it does look like high pressure will be too close for anything wintry. The ECM is in strong agreement with the GFS with the placing of high pressure.

Interesting to note is that the AO is being forecasted a steep dive into a strong negative phase between the 10th and 16th October. NAO is forecasted to remain in a weak negative although past the 15th it becomes somewhat uncertain with little agreement.

So still quite uncertain at this stage, although the mostly likely outcome I think is that high pressure will be close/over the UK and the colder 850hPa air will stay to the East of us although there will definitely be a cooler feel to things, with perhaps some widespread frosts developing during clear spells at night. Things will become more certain in the coming few days.

A friend of mine has asked me to do a quick introduction in forecasting snowfall (yes, I hear you calling me a weather geek, but I really don’t care )

This is a more advanced chart, and if you don’t understand what the 500hPa etc.. charts are, then you’ll find this very hard to understand. This guide is really for people who have an understanding of basic weather charts/terms.

There are two major models we have to look at when it comes to forecasting snow. Firstly you take a look at the GFS, and then you look at the ECM – When these two are both showing the same with (ie colder air) then the chances of it coming off are higher than say if just once of these charts were forecasting colder weather.

When looking at the GFS charts, the ideal ones to be looking at are the 500hPa and the 850hPa charts. Obviously at this stage you’re going to know all about high pressure and low pressure systems, how to read isobars etc.. so the next bit shouldn’t be too difficult for you to understand.

500hPa must be at least -27c for snow to pass through this layer of the atmosphere without melting. As it gets lower, 850hPa temperatures must be between -5c and -7c, although -5c is slightly boarder line and could end up falling as sleet depending on other factors which we’ll discuss a little later. So just a quick review

500hPa –     -27c or lower                                     850hPa -         -5c or lower, but preferably lower than -5c

Example of 500hPa at -27c or lower (Northerly Blast)

Example of 850hPa -5c or lower

As you can see on the 850hPa chart. The temperatures at -5c or lower over much of England and Wales, and -10c across Scotland. This would easily be cold enough to support snowfall. All we need to do now is look at the dew points, as long as they are at 0c or below then snowfall is certainly possible as long as the precipitation is there. There are many other factors involved but these are the basics and all you really need to know at the moment. I might add more about predicting colder patterns, but it does turn slightly more complicated on this bit. If you have any questions then just email me.

Well the winds are hitting at this time(6:58pm). Not bad but just a start…We had a few drops of the wet stuff earlier but hey, the grass needed watering. My boxer has decided that the best place to ride it out would be MY bed. So much for fresh, clean sheets. He’s only equal to 2 of my granddaughter! And HE snores. More later if the lights stay on. Wish me luck! Peace

Videographer Doug Kiesling says he risks his life for the shot “so you don’t have to,” and he fucking well means it. Kiesling videotaped a wedge tornado in Kansas earlier this week, and in the process got some of the most awesome storm footage I’ve seen in a while. Wedge tornadoes are either very large twisters (can be up to a mile wide) or a nest of funnels — meteorologists just don’t always seem too sure. Whatever the case, once you watch Kiesling tape this monster you will also be in awe of either his stupidity or his big, brass balls.