The region which has always the temperature 65 degree F or above is a tropical region. Whereas in temperate region, there is variation in temperature but not extreme of cold or hot. The region lies between the equator and pole.

54 degrees Fahrenheit

Despite warm air temperatures, the River Thames can cause cold water shock all year round. Its average temperature is 12C (54F) but water shock can occur at any temperature below 15C (59F).

Modern London has the equable climate of South East England, with mild winters and temperate summers. The average daytime air temperature is 52 °F (11 °C), with 42 °F (5.5 °C) in January and 65 °F (18 °C) in July.

68°F

The maritime Tropical (mT) is the most important moisture-bearing and rain-producing air mass throughout the year. In winter it moves poleward and is cooled by the ground surface. Consequently, it is characterized by fog or low stratus or stratocumulus clouds, with drizzle and poor visibility.

Gulf of Mexico

Maritime tropical air masses originate over the warm waters of the tropics and Gulf of Mexico, where heat and moisture are transferred to the overlying air from the waters below. The northward movement of tropical air masses transports warm moist air into the United States, increasing the potential for precipitation.

Tropical maritime air is warm and moist in its lowest layers and, although unstable over its source region, during its passage over cooler waters becomes stable and the air becomes saturated.

TROPICAL air masses will bring warm weather and POLAR / ARCTIC will bring cold. CONTINENTAL air masses have travelled over land, and will therefore bring dry weather (as they haven’t picked up much water on the way). MARITIME air masses have travelled over the sea, so will bring wet weather.

A stationary front is represented on a map by triangles pointing in one direction and semicircles pointed in the other direction. A stationary front forms when a cold front or warm front stops moving. This happens when two masses of air are pushing against each other, but neither is powerful enough to move the other.

Cold fronts form when a cooler air mass moves into an area of warmer air in the wake of a developing extratropical cyclone. The warmer air interacts with the cooler air mass along the boundary, and usually produces precipitation. Cold fronts often follow a warm front or squall line.

Cold, dense air squeezes its way through the warmer, less-dense air, and lifts the warm air. Because air is lifted instead of being pressed down, the movement of a cold front through a warm front is usually called a low-pressure system.

Cold fronts are notoriously known for their bad weather such as thunderstorms, tornadoes and heavy rain. Many of our severe weather events during the winter months are caused by cold fronts. These fronts can produce tornadoes over Florida during the winter.

The air mass behind a cold front is likely to be cooler and drier than the one before the front. If a cold front is approaching, precipitation is possible just before and while the front passes. Behind the front, expect clearing skies, cooler temperatures, and lower relative humdities.

On a weather map, a cold front is usually drawn using a solid blue line with triangles pointing in the direction of the warm air that will be replaced. Cold fronts typically move from northwest to southeast. A cold front can bring cold temperatures, torrential rains and high wind speeds.

Cold fronts generally advance at average speeds of 20 to 25 mph. toward the east — faster in the winter than summer — and are usually oriented along a northeast to southwest line.

Cold fronts can cause dramatic temperature changes and can create severe weather. A cold front is an area of cold or cooler air that moves towards warm air. When a cold front moves into an area, it will change temperatures and usually the current weather based on the strength of the cold front.