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
A consulting meteorologist is asked to evaluate wind conditions for a crane operation. Wind gusts to 35 mph are forecast. Which concept best describes the difference between sustained winds and gusts?
Answer: Gusts are brief, rapid increases in wind speed caused by turbulent eddies, lasting seconds rather than the 2-minute average defining sustained winds
Gusts are short-duration wind speed peaks caused by turbulent mixing, while sustained winds are averaged over a longer period (typically 2 minutes per NWS convention).
Which meteorological phenomenon is responsible for the Foehn effect, where air descending the lee side of a mountain range is anomalously warm and dry?
Answer: Orographic lift causes precipitation on the windward side, releasing latent heat; the drier descending air then warms dry adiabatically at a faster rate
On the windward side, moist adiabatic cooling allows latent heat release; on the leeward side, the now-drier air descends and warms dry adiabatically, arriving warmer and drier than when it started.
A Mean Absolute Error (MAE) of 3°F for a 24-hour temperature forecast indicates:
Answer: The forecast temperatures were, on average, 3°F away from observed temperatures
MAE is the average of the absolute differences between forecast and observed values, so 3°F MAE means forecasts deviated from observations by 3°F on average.
Sea breezes along the coast most commonly develop under which synoptic conditions?
Answer: Weak synoptic-scale pressure gradients and strong solar heating of the land surface
Sea breezes are thermally driven local circulations that develop when differential heating between land and sea is maximized under weak synoptic pressure gradients.
In NWS verification statistics, 'Equitable Threat Score' (ETS) differs from simple Threat Score (TS/CSI) because ETS:
Answer: Accounts for hits that would be expected by random chance, providing a fairer comparison across different event frequencies
The ETS subtracts the hits expected by chance from both the numerator and denominator, making it a more equitable measure across rare versus common events.
Which upper-air analysis tool best identifies regions of ageostrophic wind that act as forcing mechanisms for vertical motion in jet streak entrance and exit regions?
Answer: Divergence analysis of the 300 hPa isotach field
Divergence in jet streak entrance (left) and exit (right) regions at 300 hPa creates ageostrophic flow that drives upper-level divergence and upward vertical motion.
A client asks a CCM for the expected wind chill temperature when air temperature is -10°F and sustained winds are 30 mph. This value is calculated using the NWS wind chill formula, which primarily accounts for:
Answer: Increased convective heat loss from exposed skin in cold, windy conditions
The NWS wind chill index quantifies the enhanced convective heat loss from exposed human skin caused by cold wind, using a standard walking speed formula.