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IF you think the weather was warmer and wetter than normal then you could be right.
The Bureau of Meteorology (BoM) has confirmed that humidity levels have recently been above the March average in many areas in WA.
It’s classified as muggy when the dew point temperature is above 15 or 16 degrees Celsius – which was the case last weekend and earlier this week.
In Geraldton, the average monthly dew point temperature is 15.6 °C.
From March 11, it began to exceed this and reached 18.7 °C on Friday.
For those further south, the average dew point of York in March is a low 12°C, but as of March 12 it reached 15.5°C and stood at 17.5°C on Sunday.
Fog has also increased, including in areas along the Great Northam Highway to Northam.
BoM Duty forecaster Jessica Lingard said this week has been wetter due to some unusual valley activity.
“Normally, if you look at a map, our troughs are sort of vertical,” Ms Lingard said.
“They are on the west coast, but the tail of this trough sits over the southwest of the state while the head of the trough, the north end of it, has moved east as usual.”
Ms Lingard said this meant air was circulating at the bottom of the trough, where dry air came from land and collected moisture from the ocean before returning to land.
This situation is commonly seen along the Pilbara coast resulting in fog and humidity.
With the higher moisture content in the air, it is no wonder that it also rained last weekend.
BoM recorded 22.6mm at Nyabing, while Jacup had 21.2mm, Mount Barnett 21mm and Ongerup 19.6mm.
In sustained afternoon monsoon thunderstorms in Kimberley, some locations received more than 10mm.
The falls in the southern half of WA are due to an upper trough moving through, which Ms Lingard said favored the development of thunderstorms.
“The upper trough started further west of the state around Friday and just as that trough moved east it took the thunderstorms with it,” she said.
“The thunderstorms that then swept through the Eucla District and southern interior on Monday, Tuesday — they’re still the same system that swept through the Southwest.”
A cold front is expected early in the weekend late Friday and early Saturday.
“The cold front might bring some precipitation to the southwestern parts of the agricultural areas, then the coast and south coast will also see a good decline,” Ms Lingard said.
“At this time of year, in the fall, we get a couple of hot days with the troughs along the west coast, then we get a couple of days with weak cold fronts.
“We’re alternating between the summer patterns and the winter patterns, hopefully we’ll see some more winter patterns and get some rainfall where needed.”
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