Forecasting and Operational Meteorology Flashcards
7 cards from real CCM practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Forecasting and Operational Meteorology flashcards as text
Which numerical weather prediction technique uses an ensemble of model runs with slightly perturbed initial conditions to estimate forecast uncertainty?
Answer: Ensemble forecasting
Ensemble forecasting runs multiple simulations with perturbed initial conditions to sample the range of possible outcomes and quantify forecast uncertainty.
A mesoscale convective system (MCS) is most likely to develop when which of the following conditions are present?
Answer: Strong wind shear and abundant low-level moisture with an initiating trigger
MCS development requires strong wind shear for organization, ample low-level moisture for fuel, and a triggering mechanism such as a boundary or front.
When issuing a forecast for a client requiring aviation weather information, which ceiling and visibility threshold defines IFR conditions?
Answer: Ceiling below 1,000 ft AGL and/or visibility less than 3 SM
IFR (Instrument Flight Rules) conditions are defined as ceiling below 1,000 feet AGL and/or visibility less than 3 statute miles.
The Q-G omega equation relates vertical motion to which two primary forcing terms?
Answer: Differential vorticity advection and temperature advection
The QG omega equation shows that upward vertical motion is forced by positive differential vorticity advection increasing with height and warm air advection.
Which phenomenon describes the deepening of a low-pressure system by 24 hPa or more within 24 hours, commonly called 'bombogenesis'?
Answer: Explosive cyclogenesis
Explosive cyclogenesis (bombogenesis) occurs when a low-pressure system deepens by 24 hPa or more in 24 hours, producing rapidly intensifying storm conditions.
A forecaster notes a strong temperature inversion at 850 hPa. What type of precipitation is most likely at the surface if temperatures below the inversion are below freezing?
Answer: Freezing rain or ice pellets depending on the depth of the sub-freezing layer
A warm layer aloft melts precipitation to rain, which then refreezes—as freezing rain if the sub-freezing layer is shallow, or as ice pellets if it is deep enough for re-freezing in the air.
In probabilistic forecast verification, the Brier Score measures the accuracy of which type of forecast?
Answer: Probability forecasts for binary events
The Brier Score is the mean squared error of probability forecasts for binary (yes/no) events, where a perfect score is 0.