METEOROLOGY 361                                                                                                                                                                           Spring, 2008       

FINAL EXAM

 

 

Directions: This is an Open-notes exam.  Use anything you want, including the Internet.  You can’t ask each other questions but you can ask me for clarifications (no guarantee that I’ll be able to answer). Answer all parts of the questions in the blue books unless otherwise directed. You have 2 1/2 hours.

 

 

     Sign the release  on the paper copy and include an e-mail address if you wish to have your grade sent to you.  There is no penalty for not signing.

 


 

1. For this question, refer to the plotted surface observations for 1343 May 7, 2008

            a. ( 4%)  Identify one station showing a questionable observation by its three-letter code.  Also identify the particular observation you think is incorrect.

            b. ( 4%) Explain why you think the observation you picked in part a is questionable.

 

2. For this question you should review the NAM forecast loops of 48 hour MSLP, 48 hour 300 hPa, 850 hPa, and 500 hPa.

            (24%)   Write a detailed forecast for New York City for the period from 12Z on March 16, 2007 to 12Z on March 18, 2007.  Include temperatures (lows, highs), precipitation type, precipitation amount (if snow, do not melt it – give the inches of snow), and wind direction and speed.  Your forecast does not have to verify exactly as to what happened, but it must be consistent with the guidance given.

 

3. For this question, you must evaluate the risk of severe weather for the period from 06Z May 3 to 12Z May 3.  Use the forecast maps as follows:  the NAM MSLP forecast, 850 mb forecast, 700 mb forecast, 500 mb forecast, 300 mb forecast, and 200 mb forecast.

 

            a. ( 6%) On the blank U.S. map provided, draw a convective outlook for that period using the standard format for the SPC.

            b. ( 24%) Explain your reasoning for your map in part a, based on the forecast maps provided above.  You must address all factors which are favorable or unfavorable for severe weather.

 

4. For this question you need to know where Lexington, KY is.  Refer to the map of Kentucky.  Lexington (LEX) is marked with the red box. Note: on the map of Kentucky, the observations for  LEX are NOT for Feb 16, 2003 which is the verification date for this question. This map is just for location.

 

You also have the 24-hour MSLP Eta model forecast, the 24-hour 300 mb Eta forecast, and Eta model forecast loops for 500 mb and 850 mb.  The radar loop is NOT a forecast.  That is what actually happened.

 

            a. ( 6%)  What will be the precipitation type at Lexington, KY at 00Z on Feb 16, 2003?  Explain your reasoning using the guidance maps and loops.

            b. ( 5%) Run BUFKIT with the Lexington file, eta_lex.buf, initialized 00Z Feb 15, 2003.  How does the BUFKIT forecast improve your assessment of the precipitation type at Lexington for this event?    Be specific about these BUFKIT results.

 

5. This question concerns a local situation for the mid-Atlantic region at 00Z on May 5, 2007.  The 48 hour NAM verifying at that time showed heavy 6-hour precipitation (in excess of 1.5”) over coastal areas of Virginia, including Chesapeake Bay and the southern DelMarVa peninsula.  Instead, the 24-hour precipitation amounts were modest (0.81” maximum) in that area.  However, heavy rainfall occurred near Cape Hatteras (2.47” reported). 

            a. ( 5%) Using the concept of a convective parameterization scheme in the NAM (not the details of the scheme!), explain how the NAM is able to forecast such heavy rainfall.

            b. ( 6%) In this particular case, give a plausible explanation why the parameterization caused heavy rain to fall in the wrong place. You must refer to the surface map verifying at 00Z on May 5, 2007.  Also, here’s a plot of surface observations obtained from the excellent archive at Plymouth State University.  The answer lies with these two maps.

 

 

6. On December 10, 2006 the NAM 24 hour MSLP forecast showed a storm developing in the Rocky Mountain states.

            a. ( 6%) Using the 24 hour MSLP forecast, the 24 hour 300 mb forecast, the 850 mb forecast loop, and the 500 mb forecast loop, assess this storm’s potential impact on the city of Denver, Colorado (you have a small reference map of Colorado for your convenience).   Your assessment should take into account any storm-related weather events expected for the whole day on December 11, NOT JUST 12Z.  Briefly explain your reasoning.

            b. ( 5%) Using the 48 hour NAM MSLP forecast, as well as the 850 mb and 500 mb loops, what other cities will be affected by this extratropical cyclone? (Here's a map of cities)

            c. ( 5%) How will the cities in the northeast U.S. be affected? (this may be indirect but must be related)

 

 

When you are done, please turn in everything:  the question sheet, the U.S. base map for question 3, and the blue book.