Max (Celsius)

Min (Celsius)

Rainfall (mm)

AIRHEAD

32.2

24.0

7.7

TRAVELLERS

32.2

25.1

27.9

RESIDENCY

28.0

20.6

51.3

GEORGETOWN

Not Available

Not Available

Not Available

ST. HELENA

24.6

18.8

44.6

FALKLANDS

15.2

0.8

0.5

UK (Brize Norton)

11.4

1.9

20.6

UK

It was unsettled through much of the start of the week with snow in Scotland, Northern Ireland and Wales and gales for many coastal areas.  However conditions gradually improved by Easter Sunday.

Falklands

Fairly settled and dry but with strong winds at times.  However there were light winds and patches of fog during Thursday morning.

Ascension

A few showers this week and yet another record breaking temperature, with the highest maximum for April at the Airhead since records began in 1984.

St. Helena

A fairly wet week on St Helena with gusty winds at times and some occasional low cloud giving hill fog.

Along with March, April is the most likely month for a thunderstorm on Ascension.  However these are rare here, but 3 out of the 7 storms that have occurred at the Airhead since 1984 have happened in April.  A few lightning strikes occurred around 20 miles away last Tuesday evening but did not reach any closer.  However we will probably expect to see a few more showers during the rest of this month as it is the wettest on average.

Last Tuesday saw the first day of more persistent rainfall this year. The Travellers Hill site recorded 27.9mm on this day alone.  However on this same day there was only 7.5mm at the Airhead.  The greater amount of rainfall at Travellers (and Two Boats) is due to the presence of Green Mountain.  As our winds are always south-easterly the moist air is forced up over it as it moves across.  As the air moves higher it cools and as the air reaches its dew point and becomes saturated and then falls as rain.  

Raindrops are, surprisingly, not the tear-drop shape as they are usually drawn.  Infact they are more or less spherical.  Larger drops tend to actually be flatter on the bottom part due to the pressure of the air as they fall through it and resemble more of a hamburger shape.  Interestingly if there was no air resistance at all, an average sized raindrop of 2mm falling from 500m (1650ft) would smash into the ground at a frightening speed of around 224mph, making rain showers highly dangerous!  Luckily the drag of the atmosphere slows it to around 6.5m/s (about 14mph) – phew.