3 replies to this topic

[H2Otown_WX]

A lot of times there are convective blow-ups after the sun sets which seems counter-intuitive. Obviously the approach of a strong cold front could trigger these storms even at night. A basic meteorology book I have had this as an explanation: "Towering clouds that owe their growth to surface heating lose that source of energy at sunset. After sunset, however, radiation cooling at their tops steepens the lapse rate near the top of the cloud and can lead to additional upward flow of warmer parcels from below. This process is believed to be responsible for producing nocturnal thunderstorms from clouds whose growth prematurely ceased at sunset."

Just wanted to see if anyone could expand upon this further.

[weatherwiz]

Remember parcels of air will continue to rise so long as they are cooler than the air surrounding them. With the radiation cooling of the upper portion of the storm this actually allows for parcels of air to be further accelerated upward which would then in turn lead to an increase in storm intensity as well as the development of newer storms.

You can also have several other factors at play such as the increase of the LLJ during the evening hours...increasing jet energy provides extra lift which will also give parcels an upward acceleration boost.

[H2Otown_WX]

Remember parcels of air will continue to rise so long as they are cooler than the air surrounding them. With the radiation cooling of the upper portion of the storm this actually allows for parcels of air to be further accelerated upward which would then in turn lead to an increase in storm intensity as well as the development of newer storms.

You can also have several other factors at play such as the increase of the LLJ during the evening hours...increasing jet energy provides extra lift which will also give parcels an upward acceleration boost.

Thanks for the input Wiz! Do you think localized land-sea breeze convergence could come into play as well?

[CoastalWx]

Thanks for the input Wiz! Do you think localized land-sea breeze convergence could come into play as well?

At night, it would be the land breeze blowing offshore and causing convection. You see that many times off the srn coast of FL. You don't get strong convection like you would during the day since you don't have day time heating, but you can get shwrs and even some thunder.