DEPARTMENT OF GEOSCIENCES NAME _______________________

SAN FRANCISCO STATE UNIVERSITY

Metr 302.01

Fall 2009 Midterm #1

200 pts (4 pts each answer)

Part I. Surface Chart Interpretation. Questions 1 through 7 refer to the surface weather map below and the weather station data for the four weather stations shown on the map and expanded below.

Figure 1. Surface Chart for 1500Z 7 September 2007

1. Pressure System A on the chart is a

(a) an anticyclone.

(b) a low pressure area.

(d) a ridge.

(e) (b) and (c).

2. Pressure System B on the chart is a

(a) an anticyclone.

(b) a low pressure area.

(d) a ridge.

(e) (b) and (c).

3. Station 4 (see above) is reporting

(a) a thunderstorm

(b) heavy continuous rain

(c) moderate fog.

(d) heavy continuous snow.

(e) haze.

4. The station(s) with the highest relative humidity

(a) Station 1

(b) Station 2

(d) Station 4

(e) Stations 1, 2 and 3.

5. The station(s) with the lowest relative humidity

(a) Station 1

(b) Station 2

(c) Station 3

(d) Station 4

(e) Stations 1, 2 and 3.

6. The pressure at Station 4 is

(a) 952.0 mb

(b) 1005.2 mb

(d) 520 mb

(e) 1052 mb

7. The FRONT shown on the weather map is

(a) a stationary front

(b) a cold front

(d) an occluded front

Part II. Satellite and Radar Interpretation. Refer to Figs. 2 and 3. Questions 8 through 11 relate to these figures.

Fig. 2. Infrared Satellite Image, 1745 UTC 3 Oct 2007

Fig. 3. Radar Reflectivity, Charleston, South Carolina, 1803 UTC 3 Oct 2007

8. Fig. 2 shows areas of precipitation.

(a) T

(b) F

9. Fig. 3 shows areas of cloudiness.

(a) T

(b) F

10. Fig. 2 and Fig. 3 in combination would suggest to meteorologists that the dominant cloud form over

southeastern South Carolina

(a) is stratus.

(b) is fog.

(c) is cumulonimbus.

(d) is cirrus spissatus.

(e) is stratocumulus.

11. The radar network in the United States has somewhat limited utility in California because

(a) severe thunderstorms do not occur in California

(b) the radars in the California are offline at night.

(d) the mountainous areas of the state block the transmission of radar emissions (and reflections back).

(e) there are few radar sites in California.

Part III. Severe Thunderstorms (and Use of SPC Products)

Figure 4. Convective Oulook issued 1958Z 23 February 2007

12. The Convective Outlook is issued by

(a) the Storm Prediction Center

(b) the US Geological Survey

(d) the National Hurricane Center

(e) the local National Service Forecast Office

13. The Convective Outlook shown above (Fig. 4) indicates that

(a) no severe thunderstorms were expected over the United States.

(b) there is a moderate risk of thunderstorms over western Oklahoma..

(d) there is a slight chance of hurricanes forming over the Great Plains

(e) thunderstorms are expected over a large portion of the central and southern Great Plains,

and that there is a moderate risk that some of these thunderstorms will be severe over western Oklahoma, south central Kansas and NW Texas.

14. The following is the text of a Watch issued for a portion of the Great Plains. Read the text:

URGENT - IMMEDIATE BROADCAST REQUESTED

??????????????? NUMBER 761

???????????????? NORMAN OK

210 PM CDT TUE OCT 9 2001

THE ????????????? HAS ISSUED A

???????? WATCH FOR PORTIONS OF

WESTERN OKLAHOMA

NORTHWEST TEXAS

THE EXTREME EASTERN TEXAS AND OKLAHOMA PANHANDLES

EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 230 PM UNTIL 900

PM CDT.

TORNADOES...ALSO HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE WATCH AREA IS ALONG AND 55 STATUTE MILES EAST AND WEST

OF A LINE FROM 75 MILES SOUTH SOUTHEAST OF CHILDRESS TEXAS TO 55

MILES NORTH NORTHEAST OF GAGE OKLAHOMA.

REMEMBER...A ??????? WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES IN AND CLOSE TO THE WATCH AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE WARNINGS.

This text corresponds to:

(a) a Tornado Warning

(b) a Severe Thunderstorm Warning

(d) a Tropical Storm Watch

(e) a Tornado Watch

15. Which of the following is NOT included in the definition of a severe thunderstorm

(a) hail 1” or larger

(b) straight line winds 57 mph or greater

(c) frequent cloud-to-ground lightning

(d) tornadoes

(e) all of the above are part of the definition of severe thunderstorms

16. The definition for a Warning is

(a) the given weather event is not expected to occur.

(b) the given weather event is expected to occur sometime in the future, but no one can say when.

(c) the given weather event is occuring, or is observed, and is about to move into the area mentioned in the statement. Take appropriate action immediately.

(d) conditions are favorable for the given weather event to occur in the time interval and for the area specificed in the statement, although the weather event has not yet formed. Persons living in the area should listen for further statements and should take precautions in case the event occurs.

(e) is an advisory statement not meant to be taken literally.

17. The definition for a Watch is

(a) the given weather event is not expected to occur.

(b) the given weather event is expected to occur sometime in the future, but no one can say when.

(c) the given weather event is occuring, or is observed, and is about to move into the area mentioned in the statement. Take appropriate action immediately.

(e) is an advisory statement not meant to be taken literally.

18. Thunderstorms are associated with

(a) cirrus clouds

(b) status clouds

(d) cumulonimbus clouds

(e) altocumulus clouds

19. The following is the text of a statement issued by the National Weather Service:

BULLETIN - EAS ACTIVATION REQUESTED

NATIONAL WEATHER SERVICE MIDLAND/ODESSA TX

1000 PM MST WED MAR 7 2001

THE MIDLAND/ODESSA NATIONAL WEATHER SERVICE OFFICE HAS ISSUED A

* ???????????????????????????????? FOR...

CENTRAL EDDY COUNTY IN NEW MEXICO

* UNTIL 1045 PM MST

* AT 955 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR DETECTED A

TORNADO 7 MILES WEST OF WHITES CITY...MOVING NORTHEAST

AT 20 MPH.

* SOME LOCATIONS IN THE PATH OF THIS STORM INCLUDE...

AVALON...OTIS...MALAGA...WHITES CITY...CARLSBAD CAVERNS NATIONAL

PARK...LOVING...AND CARLSBAD.

TORNADOES, HAIL TO THE SIZE OF DIMES AND WIND GUSTS NEAR 60 MPH CAN BE EXPECTED IN THE WARNED AREA.

THIS THUNDERSTORM WILL ALSO PRODUCE HEAVY RAINFALL WHICH MAY CAUSE

FLOODING OF LOW SPOTS...UNDERPASSES...AND LOW WATER CROSSINGS. IF YOU

ENCOUNTER A FLOODED STRETCH OF ROADWAY...DO NOT ATTEMPT TO CROSS IT.

THE WATER MAY BE DEEPER THAN IT APPEARS.

This text corresponds to:

(a) a Tornado Warning

(b) a Severe Thunderstorm Warning

(d) a Tropical Storm Watch

(e) a TornadoWatch

20. Severe thunderstorm forecasters often look at surface dew point temperatures to make a first guess of the region expected to get strong to severe thunderstorms. The minimum summertime surface dew point temperature they look for is

(a) 30^oF

(b) 40^oF

(d) 60^oF

(e) 70^oF

21. Cumulonimbus clouds show up very well on infrared satellite images because

(a) their tops are very cold, and usually are evidenced in the primary colors on color infrared satellite images.

(b) their tops are very warm, and usually are evidenced in the primary colors on color infrared satellite images.

(d) lightning is easily detected by the infrared satellite sensor.

(e) infrared satellite images only show cumulonimbus clouds.

Part IV. Scientific Method

22. The first step in the study of a scientific problem involves collecting data (or making a set of

observations)

(a) True

(b) False

23. Once the observations are made, or the data is collected, and the scientist observes some sort of

systematic organization or pattern to the data, he or she develops an educated explanation for the pattern. This educated explanation is known as

(a) A guess

(b) An opinion

(d) A flip of the coin.

(e) A hypothesis

24. Once a theory is formulated it is tested. If the theory bears out statistically, it becomes a

hypothesis.

(a) True

(b) False

25. If the hypothesis is not borne out by experimentation, the scientist must formulate a different

hypothesis or adjust the initial hypothesis to explain the discrepancies

(a) True

(b) False

26. The fundamental underpinning of the scientific method is the principal of determinism (cause and

effect).

(a) True

(b) False

27. It is the responsibility of the scientist doing the research that he or she knows exactly what has

been done already or has been found about the problem in question.

(a) True

(b) False

28. If the research guided by the scientific method is valid, the conclusions will hold irrespective of

the state of mind, or the religious persuasion, or the state of consciousness of the investigator and/or the subject of the investigation.

(a) True

(b) False

29. The example that Zebrowski and we have used (in class) to illustrate how to use a PRINCIPLE to explain a pattern of observations of wind is that gases tend to move from high to low pressure areas.

(a) True

(b) False

Part V. Radar.

Figure 5. National Weather Service Doppler Radar Sites

30. Figure 5 above shows the location of the National Weather Service satellite reception offices.

(a) True

(b) False

31. Radar data is used directly

(a) to show areas of precipitation

(b) to infer locations of thunderstorms

(c) (a) and (b)

(d) to find cloudiness

(e) to find areas experiencing high water vapor.

32. Radar can detect precipitation up to

(a) about 1 miles from the radar site.

(b) about 10 miles from the radar site.

(c) about 100 miles from the radar site.

(d) about 500 miles from the radar site.

(e) about 1000 miles from the radar site.

33. There is dense coverage of the national radar network except

(a) in tornado alley.

(b) in the Midwest.

(d) in the Great Plains.

(e) in the intermountain West.

Figure 6a. National Radar Summary at 20:49Z 03/02/04

Figure 6b: Frederick Oklahoma Radar at 2147 UTC 03/02/04

34. The gray areas on Fig. 6a. indicate regions with no radar coverage.

(a) T

(b) F

35. Figure 6a. shows regions of the U.S. experiencing precipitation at the time of the radar plot.

(a) T

(b) F

36. The yellow and orange colors on Fig. 6b probably indicate the location of

(a) Very heavy precipitation

(b) Thunderstorms

(c) (a) and (b)

(d) Light winds.

(e) High water vapor.

37. Fig. 6b suggests that Oklahoma City was experiencing

(a) Light or Moderate rain

(b) Thunderstorms

(d) Blowing dust.

(e) Haze.

38 The time and date of Fig. 6a is

(a) 1:49 PM PDT 03/02/04

(b) 1:49 AM PDT 03/02/04

(d) 2:47 PM PDT 03/02/04

(e) 2:47 AM PDT 03/02/04

39 The time and date of Fig. 6b is

(a) 1:49 PM PDT 03/02/04

(b) 1:49 AM PDT 03/02/04

(d) 2:47 PM PDT 03/02/04

(e) 2:47 AM PDT 03/02/04

40. Besides detecting precipitation, the radar can be used to monitor

(a) motion of rainfall/storm areas.

(b) dew points.

(d) temperatures.

(e) jet streams.

41. A significant problem in the western portion of the US, is that in certain storm patterns the local radar “overshoots” the top of the precipitation or is blocked by mountains.

(a) T

(b) F

Part VI. 500 mb chart. (Questions 42 and 43 refer to Fig. 7 below)

Figure 7. 500 mb chart With Possible Polar Jet Stream Positions, 12 UTC 3 October 2007

42. On Fig. 7, the correct location of the Polar Jet Stream is indicated by the arrow labeled.

(a) A

(b) B

(d) D

(e) E

43. The conditions shown on Figure 8 are occurring roughly at an elevation of

a. 180 feet

b. 1800 feet

c. 18000 feet

d. 180000 feet

e. 30000 feet

Part VII. Dew Point Temperature. Questions 44, 45 and 46, refer to figure 8 below.

Figure 8. (Synthesis) Dew point temperatures expected at 12 UTC 5 March 2004

Note the locations A, B, and C. Assume that the actual temperature will be 67F everywhere.

44. Of the three locations shown on Figure 8, the place with the greatest amount of water vapor is at

(a) A

(b) B

45. Of the three locations shown on Figure 8, the place with the least amount of water vapor is at

((a) A

(b) B

46. Of the three locations shown on Figure 8, the place with 100% Relative Humidity is at

(a) A

(b) B

47. The dew point temperature is used by meteorologists in many ways. Which of the following is

NOT one of those ways?

(a) The dew point temperatures can be used as a rough indication of how much water vapor is present.

(b) The difference between the actual temperature and the dew point temperature is related to the relative humidity.

(c) Meteorologists can use the dew point temperature to determine how much cooling is needed to produce clouds at the observation site..

(d) Meteorologists use the dew point temperature to assess the strength of cyclones.

(e) The surface dew point temperature can be used as a very rough indicator of how prone the atmosphere is for thunderstorm formation.

48. When the temperature is cooled to the dew point temperature at the ground

(a) condensation begins, often evidenced by the formation of fog.

(b) there is much water vapor in the air.

(d) evaporation begins.

(e) rain occurs.

49. If cloud cover is observed at a weather station (indicated by the filled in station circle), then the relative humidity at that station must be 100%

(a) T

(b) F

50. The relative amount of water vapor present at a sealevel station can be estimated by the

(a) temperature

(b) dew point temperature

(d) present weather symbol

(e) wind speed