Today's Weather

[BlueHedgehog074]

Nice one, reef. Have a great birthday.

I'm actually quite amazed how high those temperatures are during the sleet and snow showers with 7.4*C and 9.1*C reported, even though the Dewpoint temperatures and 850 hPa upper temperatures are very supportive for the wintry weather.

Currently a little above 9*C with a Dewpoint temperature of -1*C. Partly cloudy, too, with the risk of some light - heavy showers.

@Thundery Wintry Showers: Good luck if you do receive some showers, but just in case, I will send you some of mine, especially any that become heavy and produce some possible hail/sleet. (though, I can only promise this if the slow moving showers just to the North reach here).

Or maybe I'll just travel a few miles North and steal other peoples showers and deviously give them to you...

[conor123]

Chilly and cloudy with showers all around but dry here at the moment, 9.7c

[reef]

Nice one, reef. Have a great birthday.

I'm actually quite amazed how high those temperatures are during the sleet and snow showers with 7.4*C and 9.1*C reported, even though the Dewpoint temperatures and 850 hPa upper temperatures are very supportive for the wintry weather.

Currently a little above 9*C with a Dewpoint temperature of -1*C. Partly cloudy, too, with the risk of some light - heavy showers.

@Thundery Wintry Showers: Good luck if you do receive some showers, but just in case, I will send you some of mine, especially any that become heavy and produce some possible hail/sleet. (though, I can only promise this if the slow moving showers just to the North reach here).

Or maybe I'll just travel a few miles North and steal other peoples showers and deviously give them to you...

Thank you

The temperature changes are what make Arctic northerlies particularly interesting at this time of the year to me. What you find is that its only the lowest layer of the atmosphere which is at such high temperatures due to solar heating, further up the temperatures are still supportive for wintriness and during the showers the freezing level readily drops and you can see sleet/snow reach the ground at remarkably high temperatures. You also then get sudden temperature drops due to downdraughts and the cutting off of the sunshine.

[BlueHedgehog074]

Cool.

I've always been curious by what causes these sharp temperature drops during showery activity.

[Thundery wintry showers]

There is an article on snow at above-freezing temperatures here, illustrating the dependence on dewpoints and by implication humidity:

http://www.sciencebits.com/SnowAboveFreezing

The red line on the graph in this link indicates how warm it has to be, given a particular humidity, before falling snowflakes start to melt. The red line also closely approximates the point at which the average of the temperature and dewpoint is zero, which is worth bearing in mind.

Given today's dewpoints the graph might imply a threshold of about 4 or 5C, but on a day like today, with a very shallow layer of relatively warm air near the surface, the time the snowflakes take to melt is also an important factor. It may well be that as a heavy shower gets underway, the shallowness of the warm layer, together with the factors Reef mentioned (downdraughts and the cutting off of sunshine) may result in some of the snowflakes only partially melting before they reach the ground, even though temperatures at the surface are in order of 7-9C. Then if the shower keeps going at a given location the temperatures fall away.

[BlueHedgehog074]

Wow, thanks. Will have a look at that.

(like the way the article starts with a question).

Temperature currently at 10*C.

Edited May 11, 2010 by Rainbow Snow

[Zenarcher]

Castlebay Isle Of Barra

Outdoor temp 7.2c

Outdoor humidity 69%

Pressure 1015.0mb

Wind direction North

Wind speed 15mph

Cloud Height 2119ft

Wet Bulb 5.2c

Total rainfall This Month 6.6mm

Dew Point 2.2c

Wind Chill -0.5c

Weather Partly cloudy sunny dry bright

[Wilxy]

Not a bad day here today sun has been coming out during the day feeling warmer in the sun.

[Spurry]

Just had a 5 min snow shower here in Buxton..!!!!!!!

We had one here in wigan this morning as well , didn't last long but i was still shocked to see it

[Stargazer]

Cool and cloudy with brighter intervals and a few spots of rain around 5.30 on the way home from Basingstoke. Currently cloudy, 10.0 deg C, wind moderate NE. Today's maximum 12.1, last night's minimum 3.3.

Edited May 11, 2010 by Stargazer

[SteveB]

Today’s weather

Pressure 1013.6hPa

Current Temp 11.9c

Highest Temp 14.0c

Lowest Temp 6.9c

Humidity 61%

Dewpoint 4.7c

Windchill 11.9c

Min Windchill 1.3c

Current Windspeed 0.0mph

Max Windspeed 8.9mph

Wind direction NW

Rain Total 0.5mm

Monthly Rain Total 9.8mm

[Terminal Moraine]

A clear and sunny start to the day after a cool night with long clear periods. Cumulus built steadily during the mornng and there were showers around by midday although here there was no more than a few spots of rain. The afternoon was also mainly dry with a few sunny intervals but at 1615 g.m.t a moderate shower moved in from the north west and turned to sleet by 1620. Since then it's been dry with a few more sunny intervals but also some large shower clouds in the vicinity.

At 1800 g.m.t;

Temp', 5.4c

Max' today, 8.8c

Min' last night, 1.5c

Grass min', -1.2c

Rainfall in 24 hrs to 0800 g.m.t, 0.2 mm

Rainfall from 0800-1800 g.m.t, 1.1mm

Sunshine today, 6.51 hrs

Mean wind speed, 6 mph W

Highest gust today, 24 mph NW at 1206 g.m.t

4 oktas cu, cb and alcu

Vis', 12 km.

Shower falling to north of station

[Kent Snow]

7.4C, clear skies, wind light, 1012mb.

[Stormyking]

Hey all, havent posted a report for 2 days which am disapointed in my self :lol:

But anyway Today has been a rather chilly day despite there being a bit more sunshine but been breezy in that N/NE wind. About 4 - 6pm there was suprising some small convective looking skies to my N/ NW and a bit to my NE which I thought was nice to see and the clouds had an Interesting structure too to them.

Now it is going quite cold out there but with a nice sunset poking threw the cloud and shining a nice orangy pinky colour on the church.

Temperatures around the Island starting from Highest to lowest:

1. Freshwater: 9.1c

2. Newport: 9.1c

3. Wroxall 8.3c

4. Bleaktown 7.9c

Todays Maximum Temperatures around the IOW starting from Highest again:

1. Newport: 12.5c

2. Freshwater: 12.3c

3. Wroxall: 11.8c

4. Bleaktown: 10.8c.

Todays Mininum Temperatures around the IOW starting from Lowest this time:

1. Bleaktown: 3.2c

2. Wroxall: 3.3c

3. Freshwater: 4.8c

4. Newport 4.9c

Will be Interesting to see how low the temperatures get tonight

[Zenarcher]

Castlebay Isle Of Barra

Outdoor temp 5.8c

Outdoor humidity 67%

Pressure 1015.5mb

Wind direction North

Wind speed 15mph

Cloud Height 2344ft

Wet Bulb 3.6c

Total rainfall This Month 6.6mm

Dew Point 0.1c

Wind Chill -3c

Weather Partly cloudy dry dark

Over The Last 24hours averages and extra details,

Temperature dropped 0.6c

Pressure dropped 1.8c

Humidity dropped 2%

Average wind speed 16mph

Dewpoint dropped 1.0c

Average wind direction North

Moon age 27 days 6%

Sunrise and Sunset 5:25am - 9:30pm

Moonrise and Moonset 4:05am - 6:46pm

[Nights King]

Might get a slight air frost tonight looking at how the temp is falling away.

Current temperature 3.6c

[TonyH]

Clear intervals last night.

Rather cloudy , sunny intervals this morning. Sunny periods pm. Cool, moderate north breeze.

Min: 3.8c @ 0530

Max: 12.1c @ 1600

Rain yesterday: 0.2mm

Rain since 10am today: Nil

Currently: Clear, very cool, seemingly on the way to an air frost.

Temp: 5.2c

Pressure: 1015mbar, rising slowly.

[Osbourne One-Nil]

Windows had to be opened earlier to help cope with the heady heights of 9.8º. Now dropped to a non-descript 3.5º.

[damianslaw]

Another cold May day after a very cold start with mins of -2 degrees. Temps climbed to 9.5 degrees. We saw some showery sleety rain early afternoon, not heavy enough for any snowflakes, but had it been heavy then I think we will have seen some given the upper temps and low dewpoints.

We are now at 3 degrees similiar to this time last night, another -2 degrees is likely tonight, some local frost hollows could get down to -3 degrees it looks like a predominantly clear night.

Have to say I do love this clear arctic pure air, great outdoor weather.

[Osbourne One-Nil]

Have to say I do love this clear arctic pure air, great outdoor weather.

Try telling that to my lawn - still haven't had to cut it this year.

[damianslaw]

0.8 degrees now, sharp fall in the last hour again just like yesterday.

[Osbourne One-Nil]

Sub zero here for the 91st time since October. Currently -0.4º and dropping quite fast, so could beat last night's -2.7º.

As interesting as I'm finding the North East Regional Spatial Strategy, I might just have to go home and make sure the fire's in for the night.

[TonyH]

4c drop over past 2 hours.

Currently +1c and frosty!

Quite a notably cold and frosty May night ahead, if it stays clear and calm should reach -3c here.

[Nights King]

Getting quite chilly outside now with a ground frost already forming!

1.1c

[Optimus Prime]

Currently 2.7c on an airborne temperature measurer to cable extender (work that one out) But still 4.9c at ground level.

Shap is already down to -2.1c at 11:00!

Edited May 11, 2010 by Optimus Prime