Seasonal Summary – Winter 2011/12 (December 1st 2011- February 29th 2012) Weather Station: Sannox, Isle of Arran

When you think of winter most people with think of ice and snow. Not this winter, this winter will be remembered for rain and severe wind. This is the first Seasonal Summary for the weather station so any comments or criticisms are welcomed. At the bottom there is a table containing the data from the summary.

Rainfall

It rained every single day from the 1st of December to the 12th of January with the wettest single day being the 3rd Jan with a total of 81mm of rain falling that day at a maximum rate of 20.6mm/hr.

Total Saturation

Total Saturation - Ground couldnt absorb any more water

Looking at the 3 months as a whole there was a grand total of 914.4mm of rainfall and 75 days with rainfall of 0.3mm or more. In the UK the Met Office only counts a “rain day” if 0.3mm or more rain falls. This means that for the winter, in Sannox at least, there was only 16 dry days out of a possible 91.

Wind

This was probably the most impressive, or scary, feature of this winter. The area where the weather station is isn’t open to the full blast of the elements and managed to record a top gust of 94.2mph, again on the 3rd of January. The gust, just one of many 80+ mph occurred at 08:20am, safe to say, I don’t think the boat sailed that day? The total combined Wind Run for the winter season was 19,173.9 miles, sounds impressive! That works out at an average of 211 miles per day. The highest wind run in one day was 764.8 miles on the 28th December. There were 14 days with Gale Force winds.

Wind run is a meteorological term used to categorize or determine the total distance (or amount) of the traveled wind over a period of time. Wind run can help to determine the rate of evaporation of moisture over a particular area. It may also be useful in determining the height of waves that might be encountered on large bodies of water. Longer wind runs generate higher waves on open water.

The high winds caused a lot of damage and power cuts which lasted for days due to the sheer number of poles that had to be replaced in harsh conditions. The power of the wind was such that it could split trees in half vertically up the trunk. Mother Nature flexed a tiny bit of her power that day.

Replacing poles

Replacing poles

The highest 10 minute average wind speed was 68.9mph at 03:43am on the 22nd January. Thats a mighty Force 11 on the Beaufort Scale, classed as a Violent Storm, and this wasn’t during the famous Hurricane Bawbag.

Temperature

Probably quite a warm winter was had due to the consistent west winds coming of the Atlantic. The minimum was -1.9°C on the 1st February, and the maximum temperature was 15.8°C on the 25th February. The Highest minimum was 10.5°C on Christmas Day which left less than a snowball’s chance of a much hoped for White Christmas. The lowest maximum was 3.3°C on the 2nd February. Because it was relatively mild, frosts were few and far between with the weather station recording 3 Air Frosts.

Snowfall

What snow!? There was some nice accumulations up the hills, but here in Sannox 102ft above sea level, snow flakes were spotted on 5 different days, and it started to accumulate on the ground only during 3 of those flurries, which technically doesn’t count as a day with “lying snow”

Pressure

The highest pressure was 1041.2HPa during the Scandinavian High blocking pattern which gave England its proper cold snap, drawing in the cold air all the way from Siberia! We were just on the edge of that so we got the high pressure but sadly not the same Arctic Blast.

The lowest pressure of 965.9Hpa. Yet another seasonal weather extreme set on the 3rd of January, what a day that was!

tree trunk split

tree trunk split

Raw Weather Data Summary for period 01/12/2011 to 29/02/2012

Temperature (°C):
Mean (1 minute)  6.7
Mean (min+max)   6.7
Mean Minimum     4.4
Mean Maximum     9.1
Minimum          -1.9 on 01/02/2012
Maximum          15.8 on 28/02/2012
Highest Minimum  10.5 on 25/12/2011
Lowest Maximum   3.3 on 02/02/2012
Air frosts       3

Rainfall (mm):
Total for period 914.4
Wettest day      81.0 on 03/01/2012
High rain rate   20.6 day 03/01/2012
Rain days        75

Wind (mph):
Highest Gust     94.2 on 03/01/2012
Average Speed    8.9
Wind Run         19173.9 miles
Gale days        14

Pressure (mb):
Maximum          1041.2 on 08/02/2012
Minimum          965.9 on 03/01/2012

Days with snow falling         5
Days with snow lying at 0900   3

Originally posted 2012-03-02 16:40:47.