Mountains can trigger rain.

Orographic Effect

Cloud Formation
Mountains pose a significant obstacle to stable air flow. As air approaches the mountain it is forced upwards. At higher altitudes, the temperatures drop, condensing water vapor. This process results in the formation of clouds. Mountains may also restrict or slow down air flow. This restriction may also result in lifting air to high altitudes and creating clouds prior to the air reaching the slopes of the mountain.
Orographic Effect
As the air is forced higher by the mountain, the clouds that were formed eventually release water in the form of precipitation. This so-called orographic effect occurs because the clouds' ability to hold moisture lessens as temperatures drop. The higher the mountain, the lower the temperatures at its peak. This forces the clouds to release the precipitation in the form of thunderstorms in the summer and severe snowstorms in the winter. The orographic effect occurs on the windward side -- the side that faces the wind. Sciencing,
How Do Mountains Affect Precipitation?, 2018

The upwind side of the mountain receives more rain while the downwind side receives sporadic rain or even dry conditions. However this was portrayed in the Quran 1400 years before it was discovered. The Quran says that higher grounds receive more rain while other grounds receive dew.

[Quran 2:265] And the parable of those who spend their wealth seeking Allah's approval, and to strengthen their souls, is that of a garden on a high ground, if heavy rain falls on it its produce is doubled and if no heavy rain falls then dew. Allah is seeing of everything you do

"Rabua رَبْوَةٍ" means high ground. In this verse the higher ground receive more rain while other grounds that didn't receive rain will receive dew. Today we know why higher ground receive more rain, this is the orographic effect.

How could an illiterate man who lived 1400 years ago have known that higher ground receive more rain?  

Miracles Of Quran

The Quran (Koran, the book of Islam) contains scientific knowledge that could not have been known 1400 years ago. It ranges from basic arithmetics to the most advanced topics in astrophysics. You are invited to go through those miracles and judge for yourself.

STUDY OF THE EARTH

Geology

Coal, Landslide, Weathering - Erosion, Porous Rocks, Mass Extinction, Steam Explosions, Mountains, Internal Waves, Earth, Pumice, Photic Zone, Tectonics, Dead Sea, Sinkhole, Volcano, Shorelines, Minerals, Hydrothermal Vents, Freshwater, Fire Whirl, Rocks Crack, Subduction, Fault Lines, Earthquake, Soil Expansion, Flash Flood.

SCIENCE OF LIVING ORGANISMS

Biology

Fetal Development, Honey, Cholesterol, Meiosis, Antioxidants, Fats, Hypoxia, Miscarriage, Gardens, Photosynthesis, White Hair, Pollination, Lightning Strike, Inner Ear, Cataracts, Vision, Bones, Milk, Brain Functions, Evolution, Honey Bees, Human Senses, Frost, Gender, Eye Pupil, Womb, Fingerprints, Skin Nerves, Fasting, Breastfeeding, Eardrum, Fetus, Fluorescence, Human Embryo, Bedsores, Perspiration, Bacteria, Plant Stress.

SCIENCE OF Quantity, SPACE, AND CHANGE

Mathematics

Distance, Prime Numbers, Pi, Arithmetics, Relational Algebra, Base-19.

study of the past

History

Paper Money, Hieroglyphs, Digital Books, Calendar, Moses, Pharaoh's Mummy, Haman, Karnak Temple, Pharaoh, Flight, Noah, Dead Sea, Pompeii, North, Petra, Water Dam.

ANIMAL SCIENCE

Zoology

Raptors, Spider Web, Ants, Honey Bees, Colonies, Animal Languages, Mosquito, Crow, Nocturnal Animals, Housefly.

STUDY OF THE ATMOSPHERE

Meteorology

Sea Breeze, Orographic Effect, Wind, Volcanic Gases, Mass Extinction, Microburst, Cloud Seeding Dew, Shorelines, Fire Whirl, Freshwater, Atmospheric Pressure, Flash Flood, Weight Of Clouds.

SCIENCE OF CELESTIAL OBJECTS

Astronomy

Sunlight, Full Moon, Meteorites, Exoplanets, Planetary Orbits, Magnetosphere, Moonlight, Day, Multi-Star System, Iron, Starlight.

SCIENCE OF ELEMENTS AND COMPOUNDS

Chemistry

Viscosity, Superionic Water, Photosynthesis, Volcanic Gases, Mass Extinction, Bones, Steam Explosions, Internal Waves, Pyramids, Hydrogen, Water Stratification, Cloud Seeding, Fluorescence, Pompeii, Rust.

SCIENCE OF MOTION AND BEHAVIOR THROUGH SPACE AND TIME

Physics

Work, Light, Atoms, Pairs, Speed Of Light, String Theory, Rayleigh Scattering, Terminal Velocity, Time Relative, Wormholes, Pulsars, Gravity, Spacetime, Armor Peircing, Gravitational Waves, Sonic Weapons, Mass, String Theory, Equivalence Principle, Red Shifting.

SCIENCE OF THE ORIGIN AND EVOLUTION OF THE UNIVERSE

Cosmology

Shape Of Universe, Age Of Universe, Seven Heavens, Big Bang, Expanding Universe, Sound Waves, Isotropy, Primordial Smoke, Dark Energy, Galaxy Filaments. Dark Energy

Please link to

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