1. DAY 3 Winners Redux = SPC

2. DAY 4 - Forecast Verification time!
Perfect Forecast ?

3. The Dr. Titley residence
(one block from campus) 82 Y 9

4. 3.5 82 Y 9
3.5

5. DAY 4 Winners

6. CLIMATOLOGY TEMPS Avg./mean: 81 Median: Range: 82 90 - 68 Std. dev. 7
Let’s talk about those temps ….
CLIMATOLOGY
This week …
Monday: 77
Tuesday: 79
Wednesday: 71
Thursday: 82
TEMPS
Avg./mean: 81
Median:
Range: 82
Std. dev. 7

7. Let’s talk about the clouds = Sat imagery
Large-scale subsidence =
Cloud killer
500 mb analysis =
Thurs. evening
Convection
Conduction
Buoyancy
Daytime heating =
Cloud maker

8. RH Calculator Relative Humidity – How close the air is to saturation
- Varies between? (X and Y %)
- If in a cloud ….. RH = ?
Dew Point – Absolute humidity (how much H20 v)
T = 85
D = 65
RH = 51%
What do we need to do to T and/or D
to produce a cloud ?
RH Calculator

11. 500 mb analysis =
Thurs. evening

12. Tornado Climatology – Whisker plots

13. Air Mass
Large volume of air with certain Temp and Moisture Characteristics
Continental Tropical, Maritime Tropical,
Continental Polar, Maritime Polar

14. Continental Polar
Maritime
Polar
Continental Tropical
Maritime Tropical

15. Summer - Day Winter- Day T = 105 TD = 38 T = 15 TD = -5 T = 67 TD = 58
Maritime Tropical
Maritime Polar
Continental Tropical
Continental Polar

16. Let’s talk about the rain …. Our forecast period

18. CLIMATOLOGY

19. THIS EVENING – 500MB
SPC

20. 500 mb map- GFS model. Valid 8 p.m. TUESDAY
Z = EDT
12z=8 am
18z=2 pm
00z=8pm
06z=?

21. TUE EVENING – SURFACE MAPH
SPC

22. WED EVENING – SURFACE MAPH
SPC

23. Tuesday
Wednesday
Upp 60s – upp 70s
mid 70s – mid 80s
SPC

24. THIS EVENING – 500MB

25. THIS EVENING – SFC map L H

26. Penn State Weather Camps
Basic Weather Forecasting Guidelines
Sat I – Sat II – Sat III - NWS – SPC - NHC – Radar - Radar - Radar
E-WALL - sfc. map 1 - sfc. map 2 - ltg

28. DEW POINT TEMP TODAY ( 2PM – 8 PM EDT)
SPC

30. THIS EVENING – 700MB RH

31. ACCUM PRECIP – 18Z TO 00Z
(2 PM – 8 PM)

32. Joe Schmo 90 Y
3.50” PA

33. WHAT IS CLIMATOLOGY ? How the weather behaves over
a long period of time.
Weather – Behavior of the atmospheric over a much shorter
period of time

34. NORMAL? CLIMATOLOGY 81 TEMPS Avg./mean: Median: Range: 82 90 - 68
30 year period - common 81
NORMAL?
TEMPS
Avg./mean:
Conforming to a
regular pattern;
typical
Median:
Range: 82
Std. dev. 7
60’s =
70’s =
80’s =
90’s = 2 8 18
RAIN
Avg./Mean:
Range:
% time:
0.15”
0-1.79”
43%

35. ASSUMES NO CHANGE ! WHAT HAPPENED … WILL CONTINUE TO HAPPEN
WHAT IS PERSISTENCE ?
ASSUMES NO CHANGE !
WHAT HAPPENED …
WILL CONTINUE TO HAPPEN

36. Climatology Forecast
Persistence Forecast
Key West Chicago
CLI 6/ 6/ 6/ 6/ 6/ 6/ 6/
AVG ERR.
1.3 9
Key West Chicago 6/ 6/ 6/ 6/ 6/ 6/ 6/
AVG ERR.

37. PSU SNOWFALL

38. Penn State Weather Camps
Basic Weather Forecasting Guidelines
Sat I – Sat II – Sat III - NWS – SPC - NHC – Radar - Radar - Radar
E-WALL - sfc. map 1 - sfc. map 2 - ltg

39. Traditional 4-Panel Model Output
SLP map + THK
500 mb
700 mb
Accumulate Precip

40. Upper Level Map (i.e. 500mb)
Balance between 2 forces ….
Pressure Gradient + ??

41. SURFACE PRESSURE (SLP)? ? ?

42. Geostationary Satellite
22,000 miles above equator

43. De donde son ustedes?

44. JET STREAM This Afternoon
500 mb (~18,000 feet) L H

45. JET STREAM – LATER THIS WEEK

46. Basic Forecast Guidelines - TEMP
Cause of temperature to change:
Sunshine?
Wind direction?

47. Location – STATE COLLEGE TEMP – PRECIP – SKY COVER
WX CAMP - Forecasting
Location – STATE COLLEGE
TEMP – PRECIP – SKY COVER ?
90F
YES

48. Joe Smith 81
Yes 8

49. Basic Forecast Guidelines
What causes rain?
Need clouds!
Will any ole cloud do?
Moisture
Bodies of water – Moisture content of air

50. NORMAL
Conforming to a standard; usual, typical, or expected.

52. Basic Forecast Guidelines
What causes temperature to change?
How much sunshine?
How much precipitation?
Wind direction?

53. Basic Forecast Guidelines
Extrapolation= Look upstream to see what’s coming!
Sat IR - Sat II - Sat VIS - Radar - sfc. map 1 - sfc. map 2 – sfc map 3

54. Basic Forecast Guidelines
The “Models”
What are they?
Lower Res. (GFS)
Higher Res. (GFS)
Higher Res. (NAM)
Higher Res. (HRRR)
MOS - Statistical guidance

55. TROF AVIS PA
TROF AVIS

56. Cyclogenesis

62. RH at 700 mb 18z WED
MOS - clouds
E-WALL - clouds

63. SFC Temperature Forecasting Techniques Climatology Persistence
Modified Persistence
Models
2 meter temp output
MOS (statistical)

64. Basic Forecast Guidelines
Climatology Forecast = averages for today
Persistence Forecast = yesterday’s values
Modified Persistence = Persistence + Any changes

65. Nighttime infrared satellite imagery suggests that the circulation associated with the low pressure area in the Gulf of Mexico is
gradually becoming better defined. However, the system is struggling to maintain organized convection near the center, and
the radius of maximum winds remains large. Based on this, the system is still maintained as a potential tropical cyclone.

66. The low is moving erratically northwestward around the southwestern portion of a deep-layer ridge located over the western Atlantic and Florida. The large-scale models suggest this ridge will strengthen some during the next 36 hours or so and cause the low to turn a little more westward. This would be followed by a northward turn around the western end of the ridge and eventual recurvature into the westerlies. Overall, there has been a left shift of the track guidance models since the previous advisory. The new forecast track is also shifted left, but it is to the right of the model consensus, especially at h. Given the nature of the circulation, though, and the fact that the wind and rain hazards extend well north and east of the center, users are encouraged to not focus on the details of the track forecast.

67. The initial intensity remains 35 kt based on partial scatterometer overpasses and continuity from the previous advisory. Significant strengthening is unlikely due to strong vertical shear caused by an upper-level trough over the northwestern Gulf of Mexico and entrainment of dry air into the system. However, the large-scale models suggest slight strengthening before landfall, and thus the intensity forecast is unchanged from the previous advisory. One change from the previous advisory is that it now appears more likely that the system would become a subtropical cyclone rather than a tropical cyclone due to the current structure of the low and interaction with the aforementioned trough. That being said, development into a tropical cyclone remains possible. The primary hazard from this disturbance is expected to be heavy rainfall over portions of the central and eastern Gulf Coast.

68. FORECAST POSITIONS AND MAX WINDS
INIT 20/0900Z 24.8N 90.1W 35 KT 40 MPH...POTENTIAL TROP CYCLONE
12H 20/1800Z 25.7N 91.0W 35 KT 40 MPH...SUBTROPICAL CYCLONE
24H 21/0600Z 26.6N 92.1W 40 KT 45 MPH
36H 21/1800Z 27.5N 93.0W 40 KT 45 MPH
48H 22/0600Z 28.9N 93.5W 40 KT 45 MPH
72H 23/0600Z 32.5N 93.5W 25 KT 30 MPH...INLAND
96H 24/0600Z 36.5N 88.0W 20 KT 25 MPH...POST- TROP/INLAND

69. Our friends …. Storms Prediction Center

70. NAM MODEL – 4 panel map
Valid at 8 a.m. (12z) YESTERDAY

71. L H H NAM MODEL – 500 mb. map Valid 8 a.m. (12z) YESTERDAY Ridge
Trough

72. NAM MODEL – SFC map
Valid 8 a.m. (12z) YESTERDAY

73. NAM MODEL – SFC map
Valid 8 P.M. (00z) YESTERDAY

74. LIFTED INDEX
Valid 2 P.M. (18z) YESTERDAY

75. 5 a.m. (09z)

76. NAM MODEL – 4 panel map
Valid at 2 p.m. (18z)

77. NAM MODEL – sfc map
Valid at 2 p.m. (18z)

78. NAM MODEL – 500 mb
Valid at 2 p.m. (18z) L
Trough
axis

79. LIFTED INDEX
Valid 2 P.M. (18z) TODAY

80. Penn State Weather Camps
Basic Weather Forecasting Guidelines
Sat I – Sat II – Sat III – Sat WV - NWS - NHC – Radar - Radar
sfc. map 1 - sfc. map 2 – sfc map 3

81. NAM MODEL – Precip. map
Totals (2 pm – 8 pm)
(18z – 00z)
GFS MODEL – Precip. map
Totals (2 pm – 8 pm)
(18z – 00z)

82. NAM MODEL – Precip. map
Totals (2 pm – 8 pm)
(18z – 00z)
GFS MODEL – Precip. map
Totals (2 pm – 8 pm)
(18z – 00z)

83. SURFACE PRESSURE ? ? ? ? ?

84. SURFACE PRESSURE

85. Warm Sector vs. Cool Sector

88. MOS – Model Output S …
Accu Friends
Wx Channel Friends
NWS Friends

89. Know what to expect! = Climo.NH RH NL RL
Know what to expect! = Climo.

91. Big Picture …. Then details 
Soundings ?
Model soundings
Other fun output
Meteograms

92. Big Picture …. Then details 
Temps + Clouds
Soundings – What are these?
Model soundings
Other fun output
Meteograms