500 hpa and prog charts

Question 1

How long after observation time are the 500 vorticity and 500 thickness charts transmitted?

Answer 1

vorticity - 2 hrs

Thickness - 3.5 hrs

Question 2

what are the letters or symbols used to indicate a vorticity maxima and a minima?

Answer 2

Maxima - C or +

Minima - A or -

Question 3

Define Isopleth

Answer 3

Line of equal or constant value of a given quantity

Question 4

The smaller the quadrilateral, the ______ the advection

Answer 4

greater

Question 5

when isopleths are parallel to the contour lines, what is the advection value?

Answer 5

0

Question 6

Define positive vorticity advection

Answer 6

Advection of higher values of vorticity, which is often associated with upward motion of the air.

Question 7

What does negative vorticty advection represent?

Answer 7

Lower levels of vorticity moving towards higher levels of vorticity

Question 8

NVA is associated with _______ and PVA is associated with _________

Answer 8

NVA - Convergence

PVA - Divergence

Question 9

PVA is indicitive of:

Answer 9

Falling pressure, rising motion, and instability

Question 10

The thickness pattern on the 500hpa chart reflects the :

Answer 10

Mean temperature of the layer between 500hpa and 1000 hpa and is proportional to the mean temperature of the air below 18000ft

Question 11

Warm thickness advection supports:

Answer 11

Cyclogenesis

Question 12

Fronts are usually located on the _____ of the thickness field.

Answer 12

warm.

Question 13

the area between the 534 and 540 dashed lines is stippled to indicate ______ and is colored ______

Answer 13

change of phase state

yellow

Question 14

The low to mid sfc prog chart (sfc to 400mb) contains:

Answer 14

• Pressure centers, surface fronts
• Surface positions of tropical storms
• significant clouds
• turbulence, freezing lvl, and icing

Question 15

the comox sfc prog chart is issued for the period of __________

Answer 15

12, 24 and 36 hr

Question 16

the CMC sig wx prog (400mb to 700mb) is prepared ____ times daily and is transmitted _____ after the GFAs.

Answer 16

4 times

1 hr

Question 17

The mid level prog contains:

Answer 17

• surface presure centers, tropical storms, frontal positions
• Significant cloud, turbulence, freezing lvl and icing

Question 18

The forecast wind chart for FL240 contains winds and temps for FL ______ and is produced by:

Answer 18

FL 240, 340 and 450

WAFC in washington, DC

Question 19

List the steps necessary for interpolating conditions between 2 points on an analyzed weather chart

Answer 19

• Recognize the chart
• Understand the plotting model
• Proportional distance
• Topography/local effects
  RUPT

Question 20

Define local effect

Answer 20

Localized weather caused by the interaction between the atmosphere and the earth’s topography

Question 21

The significance of localized weather is:

Answer 21

the localized weather doesn’t fit the synoptic picture

Question 22

what scale is a local effect?

Answer 22

mesoscale

Question 23

List the significant factors that contribute to the formation of local effects

Answer 23

Moisture
Stability
Circulation

Question 24

List the local effects that occur near water bodies

Answer 24

Moisture source
Streamers
Thermal lows
Moderated temperature extremes
Land/Sea breezes
Convergence zones
Fog/stratus

Question 25

List the local effects that occur over higher terrain

Answer 25

Orographic clouds
Wind
Persistent radiation fog
Persistent freezing rain
Windshear

Question 26

List the local effects that occur near cities/industrial areas

Answer 26

Poor visibility

Ice fog

Question 27

List the steps required to address discrepancies between current and forecast weather, prior to calling the forecast office:

Answer 27

Identify discrepancies
Determine MANAIR requirements
Apply local procedures

Question 28

What are the shortcuts to pull up upper air plots on FWGS

Answer 28

TA - Temp, t-12
TB - temp, pressure, Td
AN - tephigram
PB - sig and mandatory winds
PA - sig winds only
UP - entire upper air plot