Types
-Watch this charming and extremely informative youtube video describing fronts
-A front is “narrow transition zone between two air masses”
Cold Front
-The leading edge of a cooler mass of air (airmass = uniform temperature, humidity, pressure..span hundreds or thousands of miles)
-Generally have steeper slopes
-“During the passage of a cold front warm air is lifted as colder air pushes under it.”
-Associated weather
-Watch this youtube video describing a cold front
Warm Front
–
-“Clouds form when moist warm air overruns cold air because the warm air cools as a result of expansion as it rises.”
-Generally have shallower slopes
-Associated weather with the passage of a warm front:
This sequence of clouds will be observed –> cirrus, altostratus, nimbostratus (CAN).
| Before | During (passage of) | After | |
| Wind | Veers and increases | ||
| Pressure | |||
| Temperature | |||
| Precipitation |
Position of a Frontal Surface
Question: You have a front. You know the surface position and it’s height. What is the distance to the frontal surface? (Where your airplane will touch the FS in the air)
Formula –> The slope of the frontal surface TIMES your vertical distance (nm)
-remember to convert to common units
| Flying towards | Passing through | Leaving | |
| Precipitation | Snow | Ice Pellets, Freezing Rain | Rain |
Questions
1. Why would it be useful for you to know the distance to a FS as a pilot? Who cares? Provide some scenario where it may be useful.
2. What would be the best source of weather to find out whether there will be fronts along your route of flight?
3. What is the formula that you can use to calculate the distance from a frontal surface?
Answers
1. I’m flying along and I know there is a nasty warm/cold front ahead of me. I’m trying to remain VFR. If I want to know whether or not I would fly into this front (and in how many miles) I could use this calculation.
2. Surface analysis chart
IFR Rating 