When it comes to days with rain, all months (on average) have more wet days than dry days. Though April to July have far less rain days on average than October to January.

Around one third of days that record rainfall actually see less than 1mm of rain. This is quite steady throughout the year.

The average daily precipitation in Wishaw is around 2.4mm. This follows the trend of the monthly precipitation totals, but there is a sharp drop in April. I think this is primarily because the humidity tends to be around it's lowest in April and this favours light showers over prolonged spells of rain.

Again there is a marked drop in April of days where more than 5mm is recorded. But note a double peak in October and January.

When it comes to days with 10mm or more, these happen (on averege) less that twice per month from March to July. Notice the steep jump in August, due to rising humidities and the highest risk of thunderstorms.

Finally the occurance of very wet days (20mm+) is surprisingly unusual in Wishaw. In April it's less than once per decade and only in October is it more likely than not in any given year - thanks largely to the ocean temperatures peaking at this time of year.



From the above we can say that the most likely time for rain in Wishaw is at 6pm in mid November. And the best chance of dry weather is at 2am in late April. If only things were so simple!


Dry County

 

Yes, seriously!  Well, some of Lanarkshire at least ...The reasons behind this are fairly complex but two words sum it perfectly; rain shadow.

The centre of this rain shadow is around the towns of Lanark and Carluke. The southern boundary of this rain shadow is basically the river Clyde and it extends as far west as Uddingston, as far north as Airdrie & Shotts and as far east as Biggar. Once you move south of the Clyde annual rainfall totals increase markedly over surprisingly short distances.

Location

Average annual rainfall (approx.)

% of Wishaw

Wishaw

875mm

 

Uddingston

950mm

109%

Airdrie

900mm

102%

Cumbernauld

1150mm

133%

East Kilbride

1300mm

150%

Hamilton

1050mm

120%

Strathaven

1500mm

170%

Douglas

1100mm

128%

Lanark

800mm

90%

Shotts

950mm

109%

Bathgate

1050mm

121%

Biggar

900mm

102%

Glasgow

1050mm

120%

 

Why?

The northern slopes of the Clyde valley are sheltered from many wind directions, particularly the prevailing directions of the southwest quadrant. The higher ground that runs from south of Glasgow, through Eaglesham towards Strathaven and beyond to Tinto Hill acts as a sponge and soaks up a lot of the precipitation that otherwise would fall in North Lanarkshire if the terrain was all flat.

Ok, so it's not that dry really. But, the next time you think the weather in our county is crap - just remember - if you lived in Larkhall, East Kilbride or anywhere on the south side of the Clyde valley - it's usually raining a bit harder and for a while longer.


Click on an icon or chart for further analysis of that weather type