Weather Terminologies
Cloud Description
Clear or Sunny Skies
  • State of the sky when it is cloudless, totally clear or with a few small light clouds visible.
  • Has a total cloud cover of less than one okta.
Partly Cloudy
  • State of the sky is within 2-5 oktas total cloud cover or has between 30% to 70% cover of the celestial dome.
Partly Cloudy to at Times Cloudy
  • Mostly partly cloudy but there are times when more than 70% of the celestial dome is covered with clouds.
Mostly or Mainly Cloudy
  • The sky is mostly covered with clouds but with possible brief periods of sunshine.
  • The total cloud cover is between 6 to 8 oktas.
  • The sky is covered with clouds between 6 to 8 oktas or has more than 70% cloud cover.
  • Predominantly more clouds than clear sky.
  • For a longer period during the day, the sun is obscured by clouds.
  • The sky is totally or completely covered with thick and opaque clouds, 8 oktas or around 100% cloud cover.

Wind Description (Based from the Beaufort Wind Scale and the Saffir-Simpson Scale)
Light Winds 19 or less 10 or less
  • Wind felt on face.
  • Ordinary wind vanes moved by wind.
  • Leaves rustle.
Moderate Winds 20-29 11-16
  • Wind raises dust and loose paper.
  • Small branches are moved.
Moderate to Occasionally Strong    
  • Moderate winds mostly persist but there are instances during the forecast period that it reaches strong wind force.
Fresh Winds* 30-39 17-21
  • Small trees in leaf begin to sway.
  • Crested wavelets appear on inland waters.
Strong Winds 40-50 22-27
  • Large branches in motion.
  • Whistling heard in telephone wires.
  • Umbrellas used with difficulty.


1 Near Gale*

2 Gale

3 Strong Gale*







  • Whole trees in motion.
  • Inconvenience felt when walking against wind.
  • Twigs break off road.
  • Cars veer on road.
  • Larger branches break off.
  • Slight structural damade occurs-roofing dislodged.


1 Storm

2 Violent Storm*

3 Typhoon*



118 or more



64 or more

  • Trees uprooted.
  • Considerable structural damage.
  • Widespread damage.

*Terms that are not normally used by meteorological centers in forecasts formulation and communication

Gust - any sudden brief increase of wind speed usually less than 20 seconds followed by a lull or slackening in wind speed

Precipitation (Rain & Rainshowers) Description

I. Rains

  • Overcast sky with continuous or steady precipitation that may last several hours.
  • Has a water droplets of 0.5 mm or greater in size but if widely scattered the drops may be smaller.
  • Associated with meso-scale (synoptic) system or macro-scale (large scale) system like TC's, Easterly Waves, Monsoons, Fronts and ITCZ.

Very Light Rains
  • Scattered drops that do not completely wet an exposed surface regardless of duration.
Light Rains
  • The rate of fall is from trace to 2.5 mm per hour.
  • Individual drops easily identified and puddles(small muddy pools) form slowly.
  • Small streams may flow in gutters.
Moderate Rains
  • The rate of fall is between 2.5 mm to 7.5 mm per hour.
  • Puddles rapidly forming and down pipes flowing freely.
Heavy Rains
  • The rate of fall is greater than 7.5 mm per hour.
  • The sky is overcast, there is a continuous precipitation.
  • Falls in sheets, misty spray over hard surfaces.
  • May cause roaring noise on roofs.
Monsoon Rains Other Descriptions:
  • Heavy and continuous precipitation attributed to either the Southwest or Northeast Monsoon.
Occasional Rains
  • Not frequent but is recurrent precipitation.
Widespread Rains
  • Precipitation occuring extensively throughout an area.
Frequent Rains
  • Precipitation occuring regularly and often throughout the time duration.
Intermittent Rains
  • Precipitation which ceases at times and re-occur again.

II. Rainshowers

  • Precipitation of short duration but usually of greater intensity from convective clouds(primarily cumulus or cumulonimbus)
  • Characterized by sudden start and sudden end of precipitation, rapid change in intensity.

Scattered Rainshowers
  • The rain-bearing clouds is distributed spatially resulting to rainshowers occuring to the bigger part of the forecasted area.
Isolated Rainshowers
  • The rain-bearing clouds is small and isolated resulting to rainshowers occuring only to a small part of the forecasted area.
Occasional Rainshowers
  • There is a large amount of convective clouds and precipitation occur in most parts of the forecasted area occasionally, and varying in rainfall amount.
Squally Rainshowers
  • Showers accompanied by brief but sudden strong or gale force winds.

Sea Condition as affected by Wind Force (Based from the Beaufort Wind Scale)
Calm 0-1.5 0-3.0 0.1
  • Ripples with the appearance of scales are formed but without foam crests.
Smooth 1.5-4.0 3.0-8.0 0.1-0.5
  • Small wavelets, still short but more pronounced.
  • Crest have glassy appearance and do not break.
Slight 4.0-8.0 8.0-16.0 0.5-1.25
  • Small waves, becoming longer.
  • Fairly frequent white horses.
Moderate 8.0-11.0 16.0-22.0 1.25-2.5
  • Moderate waves taking a more pronounced long form.
  • Many white horses are formed-a change of some spray.
Rough 11.0-16.0 22.0-32.0 2.5-4.0
  • Large waves begin to form.
  • Sea heaps up and white foam from breaking waves begin to be blown in streaks along the direction of wind.
Very Rough 16.0-20.0 32.0-40.0 4.0-6.0
  • Moderately high waves of greater length.
  • Edges of crest begin to break into spindrift.
  • Foam is blown in well-mark streaks along the direction of the wind.
High 20.0-26.0 40.0-52.0 6.0-9.0
  • High to very high waves with long overhanging crests.
  • The surface of the sea takes on white appearance.
  • The thumbling of the sea becomes heavy with visibility affected.
Very High 26.0-34.0 52.0-68.0 9.0-14.0
  • Exeptionally high waves.
  • Small and medium size ships occasionally lost from view behind waves.
  • The sea is completely covered with long white patches of foam.
  • The edges of wave crest are blown into froth.
Phenomenal >34.0 >68.0 >14.0
  • The air is completely filled with foam and spray.
  • Sea completely white with driving spray.
  • Visibility very seriously affected.