A map showing the average number of thunderstorm days each year in the U.S. (2010). A dewpoint of less than this is unfavorable for thunderstorms … METEOROLOGIST JEFF HABY There are three ingredients that must be present for a thunderstorm to occur. If the conditions above are met sufficiently, showers and storms will start to gain organization as low level winds converge toward the center of the low pressure area. Several conditions are required for the development of tornadoes and the thunderstorm clouds with which most tornadoes are associated. All thunderstorms can produce severe … As a general rule, the surface dewpoint needs to be 55 degrees Fahrenheit of greater for a surface based thunderstorm to occur. Some strains of bacteria, however, can live in more acidic or more alkaline conditions. As a pilot, however, thunderstorms are one of the most hazardous conditions you can encounter. The cluster of convection will start to form bands. Thunderstorms can occur at all times of the year, and at all hours of the day (not … As it cools the water vapor condenses. They are moisture, instability and lift. This can allow the storm to persist for many hours. The pH of an environment -- a measure of its acidity or alkalinity -- is important for bacterial growth. Thunderstorm Formation and Aviation Hazards By Ken Harding, Meteorologist in Charge, WFO Topeka, KS Thunderstorms are one of the most beautiful atmospheric phenomenon. But don't be fooled! The result is a strong, persistent updraft of warm moist air. In a supercell, a moist, unstable body of warm air may be forced to rise by an approaching cold front. NOAA National Weather Service. A Tropical Storm Watch is issued when Tropical Storm conditions, including winds of 39-73 mph, pose a POSSIBLE threat to a specified coastal area within 48 hours. Most thunderstorms form with three stages: the cumulus stage when storm clouds form, the mature stage when the storm is fully formed, and then the dissipating stage when the storm weakens and breaks apart.. A severe thunderstorm watch means that general weather conditions are favorable for severe thunderstorms to form. In severe thunderstorms, this cycle is extended because of differences in the inflow of warm, moist air into the thunderstorm. In the spring and summer months, thunderstorms seem to occur like clockwork. Supercell thunderstorms occur when very strong updrafts are balanced by downdrafts. The key to sustaining multicell thunderstorms is the "restrained" gust front initiating new storms, which requires stronger low-level wind flow relative to the movement of the storms compared to what occurs when single-cell thunderstorms form. Most strains of disease-causing bacteria prefer to grow in conditions with a near neutral pH, similar to the pH of the human body. Abundant low level moisture is necessary to contribute to the development of a thunderstorm, and a "trigger" (perhaps a cold front or other low level zone of converging winds) is … Thunderstorm, a violent short-lived weather disturbance that is almost always associated with lightning, thunder, dense clouds, heavy rain or hail, and strong gusty winds.Thunderstorms arise when layers of warm, moist air rise in a large, swift updraft to cooler regions of the atmosphere.There the moisture contained in the updraft condenses to form … As the convection increases, the warm air near the surface rises and cools. Tropical Storm Warning A Tropical Storm Warning is issued when Tropical Storm conditions, including winds of 39-73 mph, are EXPECTED in a specified coastal … If the updraft is slanted, then the rain that falls out of the cloud will not cut off the inflow of the moist air that is the thunderstorm's fuel, allowing it to continue for a much longer time period. When warm, moist air moves upward in an updraft, puffy cumulus clouds may form in the … The Cumulus Stage.