Geography 217: Weather    

Geography 217: Weather                                                                              Name:

Doppler Radar Exercise: Using Weather Underground      Date:

Part 2: Birmingham, AL Doppler Radar:

Go to  Understanding Radar – Weather Underground

Composite Reflectivity – 124 NMI range

6. Weather Underground’s Composite Reflectivity (echo intensity) figure merges the highest reflectivity from all scans. From this image, how would you explain the structure and intensity of this storm?  (Use directions relative to Montgomery AL and Columbus GA)

Storm Total Surface Rainfall Accumulation – 124 NMI Range

7. Refer to “Understanding Radar” (Weather Underground). How could this type of image be useful for cities like Birmingham or Columbus?  How would the impacts of a 3 to 5 inch rainfall event differ in Columbus and Montgomery versus a rural area?

Echo Tops – 124 NMI Range

8. What type of clouds are present here based on the maximum echo value?

Velocity Azimuth Display Wind Profile – 124 NMI Range

9. Examine the 23:43 column for Birmingham AL.  When the plane takes off, what in the wind direction and velocity?  At what altitude(s) does the wind shift?  Describe this shift in direction and velocity.

How would you describe the trend of this profile over time at 12,000 feet (youngest to the left, oldest to the right)? Incorporate direction, speed, and altitude into your answer (note KFT = altitude in thousands of feet).

NOAA: 250 MB Chart

10.  Examine the 250 mb chart (approx. 36,000 ft) above taken at 8 am CDT 10/4/21. What are the wind speeds and direction of winds over Birmingham, AL? Do they coincide with the Velocity Azimuth Display Wind Profile figure? {Compare the 250 mb Chart to the 23:37 (6:37 pm) data from the Velocity Azimuth Display Wind Profile}

NEXRAD Part 3:  Bethel AK 10/4/21 at 3:26 pm ADT

11. Using your FAA Guide to ppt. intensity handout, Describe the precipitation intensity that is occurring in Southwestern Alaska using Bethel as a base point.

12. After checking the rain/snow icon, describe the two types of precipitation occurring.  Use the FAA Guide To describe intensity.  Which mode of ppt is the most dangerous for flying and where is it occurring?

13. Based on the data above (including the two previous images), what type of cloud dominates this storm? Justify your answer.

14. How many inches of snow have fallen at Bethel’s airport? (Use a ratio of 10” of snow = 1” of rainfall)?

15. Assume that you are taking off at 23:32 in a Boeing 737 (Bethel’s airport handles commercial jets), describe the wind velocity and direction at take-off and at what altitudes does it change? Notice that from 9 KFT to 30 KFT the direction remains constant.  What is this direction?  What is the velocity at 18 KFT (approx. 500 mb) and 30 KFT (approx. 300 mb)?

Part 4: How do I Access radar images at weather underground?

  2. Click the maps and radar heading
  3. Scroll to radar maps and click
  4. Map of USA appears. Find an area with weather
  5. Click US regions and scroll to an appropriate region and click [WA-Tacoma (ATX) for example]
  6. Regional image appears and select a doppler radar [Portland OR (RTX)]
  7. Base reflectivity scan at .5° 248 NM  appears
  8. Scroll on icon Base reflectivity scan at .5° 248 NM appears for additional images

16. Find a region of the USA that is having some “weather.”  Describe what you are seeing based on a 124 NM Composite scan (attach the image).