Rain, Snow, and RF, What the Environment Does to Cellular Signals
Posted by Gordon Reed on 9th Dec 2025
Cellular antennas operate in an environment that is never static. Weather changes the atmosphere, and the atmosphere directly influences how RF energy travels between a device and a cell tower. LTE and 5G networks are designed to remain stable in most conditions, but certain weather events can cause temporary shifts in signal strength, noise levels, and overall performance.
Rain and Moisture, Why Wet Conditions Matter:
Rain Fade Basics
Rain absorbs and scatters RF energy. When the air fills with large water droplets, the link between your antenna and the tower becomes slightly less efficient.
- Low-frequency LTE bands feel only mild effects.
- Mid-band 5G can see a more noticeable drop in signal.
- mmWave bands are especially sensitive to heavy rainfall.
Your router may show lower RSRP or a drop in SINR during storms as the modem adjusts to compensate.
Fog and Condensation
Fog introduces very small droplets, which cause much less attenuation than rain. The bigger issue is condensation forming on the antenna radome. Moisture on the surface slightly changes how the antenna radiates, which can shift tuning and increase mismatch loss.
Snow and Ice, How Winter Conditions Influence RF:
Dry Snow vs Wet Snow
Dry snow contains very little water and causes minimal change to the signal.
Wet snow behaves more like rain and can weaken the link more noticeably.
Ice Buildup
Ice adds weight and changes the dielectric environment around the antenna. This can shift the resonant frequency and reduce efficiency. Directional antennas and MIMO arrays are more sensitive because their patterns and alignment are more precise.
Temperature Shifts and Their Effects:
Antenna and Material Changes
When materials expand or contract with temperature, the antenna’s tuning can shift slightly. Most wideband LTE and 5G antennas are designed to handle this gracefully, but extreme temperatures can still influence impedance and match quality.
Modem and RF Front End Components
Temperature also affects the electronics inside a router. Amplifiers, filters, and other RF components can gain or lose efficiency depending on heat or cold. Higher temperatures increase thermal noise, which may reduce SINR.
Wind and Mechanical Movement:
Directional Antennas and Alignment
Wind does not weaken RF energy itself, but it can move antennas. Directional antennas must stay aligned with the tower to deliver a strong signal. Even minor movement changes the link budget.
Cable Stress
Wind vibration places strain on coax cables and connectors. Over time, this can increase loss or create intermittent issues. Weather-rated coax and proper strain relief help prevent these problems.
Humidity and Pressure Changes:
Humidity
Higher humidity means more water vapor in the air, which slightly increases attenuation, especially at higher frequencies. While usually small, it can contribute to overall variation in performance.
Atmospheric Pressure
Pressure influences air density, which changes how RF signals bend as they travel. This can make coverage feel stronger one day and weaker the next, especially near coastlines or at high altitudes.
Storm-Related Electrical Noise
Lightning does not block RF signals, but it produces strong, wideband electrical noise. This noise raises the background interference level for a short period, which can cause momentary drops in SINR or throughput.
Weather Resilience, Building a Stable Outdoor Setup:
Antenna Construction and IP Ratings
Outdoor antennas use sealed radomes and weather-resistant materials so that moisture cannot reach the radiating elements. UV protection also prevents long-term detuning.
Using MIMO to Stabilize Performance
MIMO antennas help maintain stable connections during variable weather. By using multiple signal paths, the system can continue performing well even if one path experiences temporary fading.
Cables and Connectors
Low-loss, outdoor-rated coax such as AGA400 or AGA240 protects the link from weather exposure. Proper sealing at the connectors prevents corrosion and impedance changes.
Checking Performance During Weather Events
Most cellular routers display live RF metrics. Tracking RSRP, RSRQ, and SINR before, during, and after a storm can quickly reveal how the environment is affecting the link. Throughput tests and modem data rates show how the network adapts.
What This Means for You:
Weather does influence cellular antenna performance, but modern antenna designs and RF components minimize the impact. Rain, wet snow, and ice create the most noticeable changes, while temperature, humidity, and wind introduce smaller variations. A well-built outdoor setup using quality antennas, weather-rated cabling, and stable mounts ensures you get consistent performance throughout the year.
AntennaGear provides outdoor-rated antennas and AGA-series low-loss cables that help maintain strong, reliable connections even when conditions change.