METR 360 Fall, 2017

Final Exam

Directions: Answer questions in the blue books (or text file), except for the map drawing questions and question 7. You may instead write a text file which you e-mail to Jerome.Blechman@oneonta.edu. For calculations, show all work. You may use any source, including your notes, any textbook or the Internet. You may NOT talk during the exam, except to me. Raise your hand if you have a question.  

The following information may (or may not) be useful:   

1. The following is METAR code for Buffalo, NY (KBUF):

KBUF 062354Z 27018G25KT 9SM -SN BKN045 02/M02 RMK AO2 SLP109 58013 60021
 
 ( 7%) Plot the observations on a standard station model.  Please draw it on the question page.
 
 
2. For this question, use the GFS and NAM text guidance shown below. This is actual guidance initialized at 12Z. The location is Houston, TX. You have 48 hours of guidance spread out over 
three days, labeled day XXX (first), day YYY (second) and day ZZZ (third):
 
KHOU GFS MOS GUIDANCE 1200 UTC
DT /XXX /YYY  /ZZZ 
HR 18 21 00 03 06 09 12 15 18 21 00 03 06 09 12 
N/X 43 51 34 
TMP 41 40 41 43 46 46 47 45 45 46 44 43 42 39 36 
DPT 38 38 38 37 38 39 39 37 34 32 30 30 29 27 23 
CLD OV OV OV OV OV OV OV OV OV OV OV OV OV OV OV 
WDR 02 01 01 01 02 02 01 01 01 36 36 35 35 35 34 
WSP 13 13 14 14 13 14 14 14 14 15 12 12 13 11 10 
P06 82 70 100 100 50 41 28 
P12 100 100 46
Q06 3 1 3 3 1 1 0 
Q12 3 3 1 
T06 1/ 0 0/ 0 0/ 0 1/ 7 1/ 0 0/ 3 1/ 3 
T12 1/ 6 3/ 7 2/ 8 
POZ 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
POS 0 0 0 0 1 6 17 16 10 10 19 37 40 59 70 
TYP R R R R R R R R R R R R R S S 
CIG 5 5 6 6 6 6 6 6 6 7 7 7 7 7 8 
VIS 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 
OBV N N N N N N N N N N N N N N N 

Station: KHOU Lat: 29.63 Lon: -95.28 Elev: 36  GFS
Initialization Time: 1200 UTC
PARAMETER/TIME 000 006 012 018 024 030 036 042 048 
------------------- ------ ------ ------ ------ ------ ------ ------ ------ ------ 
 DAY / HOUR XX/12 XX/18 YY/00 YY/06 YY/12 YY/18 ZZ/00 ZZ/06 ZZ/12 
------------------- ------ ------ ------ ------ ------ ------ ------ ------ ------ 
TEMPS
 SFC (2 M) (F) 47 45 45 44 44 46 46 43 38 
 850 MB (C) 10 6 5 2 -1 -1 -3 -5 -3 
 700 MB (C) 3 2 1 0 -1 -3 -4 -7 -8 
 500 MB (C) -11 -11 -11 -11 -12 -14 -15 -17 -20 
 1000-500 THCK 558 557 555 553 550 548 545 541 538 
 
MOISTURE
 30 M AVG RH 79 83 83 84 81 76 64 55 41 
 850 MB DP/RH 9/94 5/95 3/89 2/95 -1/97 -2/91 -10/60 -8/75 -28/13 
 700 MB DP/RH 2/92 2/99 1/99 0/99 -2/99 -3/97 -4/99 -8/97 -14/62 
 500 MB DP/RH -12/96 -11/98 -12/92 -11/99 -12/99 -14/96 -16/92 -17/99 -22/82 
 CONV PRECIP (IN)
 TOTAL PRECIP (IN) 0.23 0.16 0.10 0.16 0.17 0.04  0.03 0.01 
 
WIND DD/FFF (Kts)
 30 M AVG 04/017 03/017 02/018 03/017 02/019 02/016 01/016 34/017 35/015 
 850 MB 02/011 05/012 04/011 06/016 05/024 03/025 02/027 36/015 34/024 
 700 MB 26/027 23/022 24/026 24/022 24/026 25/023 26/026 27/017 29/023 
 500 MB 25/049 26/058 26/063 25/063 25/068 25/064 25/063 24/063 25/076 
 250 MB 27/084 27/078 27/088 25/088 25/091 24/096 24/108 25/121 25/120 
 
VERTICAL VEL (uB/S)
 850 MB 2  -11 5 -6 -31 -2 -19 -13 
 700 MB 85 51 22 24 -8 19 4 -27 
 500 MB 34 -3 25 39 10 19 77 -15 
 
OTHER
 MSL PRES (MB) 1025 1027 1026 1026 1026 1026 1025 1027 1026 
 500 MB HGT (DM) 579 579 576 575 571 569 565 563 558 
 500 MB ABS VORT 0.5 7.5 5.4 6.4 9.7 18.5 -1.1 17.4 13.0 

KHOU NAM MOS GUIDANCE 1200 UTC
DT /XXX /YYY  /ZZZ 
HR 18 21 00 03 06 09 12 15 18 21 00 03 06 09 12 
N/X 41 50 34 
TMP 45 43 42 46 45 44 44 47 46 45 42 45 41 38 36 
DPT 42 43 42 42 41 40 41 41 38 36 34 28 27 24 22 
CLD OV OV OV OV OV OV OV OV OV OV OV OV OV OV OV 
WDR 01 02 36 02 02 02 01 01 35 36 36 36 35 35 35 
WSP 14 16 16 15 14 16 12 10 11 10 13 18 17 15 10 
P06 68 78 78 60 44 49 31  
P12 79 61 53 
Q06 3 2 3 1 1 1 1 
Q12 4 2 1 
T06 1/ 0 1/ 0 0/ 0 0/ 1 0/ 0 1/ 3 1/ 3 
T12 1/ 0 0/ 1  1/ 6 
POZ 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 
POS 0 0 0 0 1 6 4 9 18 21 22 43 51 58 51 
TYP R R R R R R R R R R R R S S S 
SNW 0 0 
CIG 3 3 3 3 3 4 4 5 7 6 6 6 6 5 7 
VIS 4 7 5 7 7 7 7 7 5 7 7 7 7 7 7 
OBV BR N BR N N N N N BR N N N N N N 

 
 
Station: KHOU Lat: 29.63 Lon: -95.28 Elev: 36 NAM
Initialization Time: 1200 UTC
PARAMETER/TIME 000 006 012 018 024 030 036 042 048
------------------- ------ ------ ------ ------ ------ ------ ------ ------ ------
 DAY / HOUR XX/12 XX/18 YY/00 YY/06 YY/12 YY/18 ZZ/00 ZZ/06 ZZ/12
------------------- ------ ------ ------ ------ ------ ------ ------ ------ ------
TEMPS
 2 M (F) 46 44 44 42 45 47 39 35
 850 MB (C) 6 5 3 0 -2 -5 -6 -5
 700 MB (C) 4 2 2 -1 -2 -5 -8 -9
 500 MB (C) -11 -11 -10 -11 -13 -14 -16 -18
 1000-500 THCK 558 557 555 551 548 546 540 537
 
MOISTURE
 2 M DEW POINT (F) 44 42 42 41 42 37 30 27
 850 MB DP(C)/RH 5/96 5/98 2/98 -1/97 -6/73 -8/76 -7/90 -16/43
 700 MB DP(C)/RH 4/98 2/99 2/98 -1/97 -3/97 -5/96 -9/94 -11/88
 500 MB DP(C)/RH -13/84 -12/95 -11/95 -12/92 -15/87 -16/89 -18/88 -21/79
 PRCPABLE WTR (IN) 1.32 1.29 1.21 1.06 0.91 0.75 0.65 0.48
 CONV PRECIP (IN) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
 TOTAL PRECIP (IN) 0.14 0.24 0.25 0.25 0.12 0.04 0.01 0.06
 
WIND DD/FFF (Kts)
 10 M 02/011 01/013 02/011 01/010 35/007 36/009 34/013 34/008
 850 MB 05/018 02/014 03/019 05/023 03/022 02/025 02/020 35/027
 700 MB 22/028 22/027 23/032 25/026 25/022 24/030 26/019 30/024
 500 MB 26/062 25/062 25/060 25/067 25/063 25/066 24/073 23/075
 250 MB 26/077 27/086 25/089 25/098 24/104 23/113 24/115 24/118
 
PRESS/HEIGHTS
 MSL PRESSURE 1025.8 1024.8 1025.1 1026.0 1026.4 1024.8 1027.7 1026.3
 850 MB HGT 153 152 152 151 152 151 151 149
 700 MB HGT 312 310 309 307 306 304 303 300
 500 MB HGT 579 577 575 572 569 566 562 558
 250 MB HGT 1076 1074 1071 1066 1062 1054 1047 1040
 
VERTICAL VEL (uB/S)
 850 MB 41 9 -3 -5 -26 -27 -25 -34
 700 MB 71 122 34 19 3 18 16 -14
 500 MB -11 1 17 39 37 62 43 78
 
  Here are your questions about the guidance:

a. ( 5%) Precipitation was similar in both models but the NAM concentrated most of it into the first 12 hours of day YY. There is one forecast parameter that shows you a good physical 

cause for this behavior. What is that parameter and how does the NAM forecast of that parameter differ from its GFS counterpart? Be quantitative (use numbers).

b. ( 5%) Forecast temperatures go down at all levels from day YYY to day ZZZ. What causes that to happen? You will need to visualize the weather map for this.

c. ( 4%) The GFS has performed better than the NAM this Fall. If you were forecasting for KHOU in the WxChallenge what are the four forecast numbers, based completely on the GFS 

initialized at 12Z on day XXX?

3. Examine the surface map for 12Z on an Autumn day in 2017. This map is not analyzed but does have stations plotted from various states in the Great Plains. Dodge City, KS is marked on the

map as DDC. Dodge City is a radiosonde station and the 12Z sounding link is also provided to you for parts c and d.

a. ( 8%) On the paper map provided, draw isotherms in red ink using a 10°F contour interval, including 50°F. Do not draw isotherms that are not supported by the station data on this map. 

Watch out for local effects which aren’t part of the synoptic-scale system.

b. ( 4%) Based on your isotherm analysis and the station data shown, draw a cold front in blue in the proper geographical location. Use the standard cold front symbols.

c. ( 6%) If you only had the KDDC sounding, what two features shown on that sounding would tell you that a strong cold front was represented? Briefly explain how each of your features show 

you there is a cold front.

d. ( 9%) Looking at the sounding for KDDC, consider the stability of the 825-875 mb layer, the 650-825 mb layer, and the 400-550 mb layer. Identify the stability of each of those three layers 

and write a short explanation of why each layer has that stability. Do not simply list stability types.

4. For this question, refer to the NAM forecast maps or PowerPoint loops: 1000-500 mb thickness, MSLP/10 m wind/2 m temperature, 850 mb, 500 mb. You also have the Great Lakes surface 

water temperature map. A lake effect band was forecast to develop in central New York, from Lake Ontario to Oneonta by 12Z on Nov 20, 2017 and it did.

( 6%) Of the factors we learned about, which ones were favorable for lake effect snow bands in central New York?

5. Click here for a 500 hPa map on an unspecified day in 2017. 
 ( 6%) Calculate the speed of the wave pattern shown in the U.S. and southern Canada. Estimate everything you need to make your calculation from the map and specify what those 
parameters are. Include units. Show all the steps in your calculations.  Here is a possibly useful link for DaftLogic.
 
 
6. For this question, view the 500 mb map of station plots for 12Z on some January day. You also have a paper copy of this map.
 a. ( 5%) On the paper map, draw the isotachs for 50 kt, 70 kt, and 90 kt. Label your isotachs. 
 b. ( 2%) At which station is the jet streak? Give me the station ID (3-letter code to the southeast of each wind flag).
 c. ( 4%) Also on the paper map, mark the location of the maximum vorticity with the letter “X”. Mark the location of the minimum vorticity with the letter “N”. Make them large and readable.
 d. ( 8%) Also on the paper map, mark the areas of PVA and NVA. (Remember there are four of these)
 e. ( 6%) Just based on this 500 mb map, where would be the most favorable places (refer to states and/or the station IDs) for surface Low pressure centers at the time of this map? Why did you
pick the places that you did?

 
7. ( 15%) Suppose you are working in a weather office and you must prepare a briefing of the meteorological situation in central New York for your boss (me). I have limited time to read your 
assessment before I need to go to my boss and brief her. Don’t make me look bad! Base your briefing on the GFS forecast initialization and maps linked below. You are writing this for a meteorologist 
to read. Be as specific or as general as you think appropriate for this job.
 
You must type your briefing into a text file. Use Microsoft Word if you are using a PC, Pages or Word if you are on a Mac, and Open Office Writer if you are on a Linux computer. Write a maximum 
of 5000 characters, including spaces. That’s about one page of text. Each of these programs can count characters and usually, if you click the word count it will show the character count. In MS Word 
the word count is in the lower left corner. In Pages, click on the View menu and select word count. In Writer, click on the Tools menu and select word count. You will lose points if you are over 5000 
characters so choose carefully what you write. You may not need to include anything from some of the maps if they are not important to the situation.  Send the file to Jerome.Blechman@oneonta.edu. 
 
Grading: I want to see if you can identify what is important on these maps and if you understand how these important features affect the weather. I also want to assess how you integrate the various 
weather features into the big picture of what is happening in the atmosphere. I want to see if you can write about the weather efficiently (hence the character limit). I will take points off if you write 
something that is incorrect. So be careful.
 
Here are your map links:
00Z CONUS
12 hour surface prog
Loop of IR satellite images
Loop of Northeast radar images
Loop of GFS 1000-500 mb thickness forecast maps at 1-hour intervals
Loop of GFS forecast maps at 3-hour intervals
Loop of GFS 850 mb forecast maps at 3-hour intervals
Loop of GFS 500 mb forecast maps at 3-hour intervals 
Loop of GFS 250 mb forecast maps at 3-hour intervals