0. Overview
Start with a large-scale overview of current conditions, using visible and infrared satellite images, a composite surface weather map, one for conditions aloft, and perhaps others (such as jet stream maps).
Then address selected items of the forecasting assignment.
1. Forecast location: KSFO
2. 12Z Temperature
Links:
· Meteogram ending 00Z Feb 26, 2010
· NWS Point Forecast issued 2:38 pm PST Feb 25, 2010:
Tonight: A 20 percent chance of rain after 10pm. Cloudy, with a low around 51. South wind between 6 and 9 mph.
· Computer model (NAM) forecast of winds and temperature for12Z Feb. 26, 2010 in the S.F. Bay area
Discussion: [Enter a description of how you determined your forecast. It should be detailed enough for someone else to reproduce it if necessary.]
Forecast: 52°F
3. Will cloudiness affect the 12Z temperature tomorrow?
Links:
· NWS Point Forecast issued 2:38 pm PST Feb 25, 2010:
Tonight: A 20 percent chance of rain after 10pm. Cloudy, with a low around 51. South wind between 6 and 9 mph.
· wunderWiki: “Educational: Partly Cloudy” (an attempt to interpret the languages used in NWS cloudiness forecasts)
Discussion: [Enter a description of how you determined your forecast. It should be detailed enough for someone else to reproduce it if necessary.]
Forecast: Yes
4. Will a front affect the 12Z temperature tomorrow?
Links:
· NWS Hydrometeorological Prediction Center Short Range Forecasts
· Verification area for fronts affecting KSFO
Discussion: [Enter a description of how you determined your forecast. It should be detailed enough for someone else to reproduce it if necessary.]
Forecast: Almost, but not quite, a cold front!
5. Will temperature advection be significant at 12Z tomorrow?
Links:
· Computer model (NAM) forecast of winds and temperature for 12Z Feb. 26, 2010 in S.F. Bay area
Discussion: [Enter a description of how you determined your forecast. It should be detailed enough for someone else to reproduce it if necessary.]
Forecast: No
6. 18Z Temperature
Links:
· Meteogram ending 00Z Feb 26, 2010
· NWS Point Forecast issued 2:38 pm PST Feb 25, 2010:
Tonight: A 20 percent chance of rain after 10pm. Cloudy, with a low around 51. South wind between 6 and 9 mph.
Friday: Rain. High near 59. Breezy, with a south wind between 16 and 24 mph, with gusts as high as 32 mph. Chance of precipitation is 90%.
· Computer model (NAM) forecast of winds and temperature for 18Z Feb. 26, 2010 in the S.F. Bay area
Discussion: [Enter a description of how you determined your forecast. It should be detailed enough for someone else to reproduce it if necessary.]
Forecast: 55°F
7. Will cloudiness affect the 18Z temperature tomorrow?
Links:
· NWS Point Forecast issued 2:38 pm PST Feb 25, 2010:
Friday: Rain. High near 59. Breezy, with a south wind between 16 and 24 mph, with gusts as high as 32 mph. Chance of precipitation is 90%.
· wunderWiki: “Educational: Partly Cloudy” (an attempt to interpret the languages used in NWS cloudiness forecasts)
Discussion: [Enter a description of how you determined your forecast. It should be detailed enough for someone else to reproduce it if necessary.]
Forecast: Yes
8. Will a front affect the 18Z temperature tomorrow?
Links:
· NWS Hydrometeorological Prediction Center Short Range Forecasts
· Verification area for fronts affecting KSFO
Discussion: [Enter a description of how you determined your forecast. It should be detailed enough for someone else to reproduce it if necessary.]
Forecast: Maybe a cold front, but it’s a very close call!
9. Will temperature advection be significant at 18Z tomorrow?
Links:
· Computer model (NAM) forecast of winds and temperature at 18Z tomorrow in S.F. Bay area
Discussion: [Enter a description of how you determined your forecast. It should be detailed enough for someone else to reproduce it if necessary.]
Forecast: No
10. What will the wind speed be at 18Z tomorrow?
Links:
· NWS Point Forecast issued 2:38 pm PST Feb 25, 2010:
Friday: Rain. High near 59. Breezy, with a south wind between 16 and 24 mph, with gusts as high as 32 mph. Chance of precipitation is 90%.
· Computer model (NAM) forecast of winds and temperature at 18Z Feb. 26, 2010 for S.F. Bay area
Discussion: [Enter a description of how you determined your forecast. It should be detailed enough for someone else to reproduce it if necessary.]
Forecast: 17 knots
11. What will the wind direction be at 18Z tomorrow?
Links:
· NWS Point Forecast issued 2:38 pm PST Feb 25, 2010:
Friday: Rain. High near 59. Breezy, with a south wind between 16 and 24 mph, with gusts as high as 32 mph. Chance of precipitation is 90%.
· Computer model (NAM) forecast of winds and temperature at 18Z Feb. 26, 2010 for S.F. Bay area
Discussion: [Enter a description of how you determined your forecast. It should be detailed enough for someone else to reproduce it if necessary.]
Forecast: South
12. Will there be precipitation between 12Z tomorrow and 12Z the next day?
Links:
· NWS Hydrometeorological Prediction Center Short Range Forecasts:
o 12Z Feb. 26, 2010
o 18Z Feb. 26
o 00Z Feb. 27
o 12Z Feb. 27
· NWS Point Forecast issued 2:38 pm PST Feb 25, 2010:
Tonight: A 20 percent chance of rain after 10pm. Cloudy, with a low around 51. South wind between 6 and 9 mph.
Friday: Rain. High near 59. Breezy, with a south wind between 16 and 24 mph, with gusts as high as 32 mph. Chance of precipitation is 90%.
Friday Night: Showers and possibly a thunderstorm. Low around 50. Breezy, with a south southwest wind 22 to 25 mph decreasing to between 11 and 14 mph. Winds could gust as high as 33 mph. Chance of precipitation is 90%.
Discussion: [Enter a description of how you determined your forecast. It should be detailed enough for someone else to reproduce it if necessary.]
Forecast: Yes
13. Which of the following factors (if any) will favor precipitation between 12Z tomorrow and 12Z the next day?
· Moisture content
· Frontal position
· Atmospheric instability
Links:
· Computer model (NAM) forecasts of relatively humidity at the 850 mb level
o 12Z Feb. 26, 2010
o 00Z Feb. 27
o 12Z, Feb. 27
· NWS Hydrometeorological Prediction Center Short Range Forecasts
o 12Z Feb. 26, 2010
o 18Z Feb. 26
o 00Z Feb. 27
o 12Z Feb. 27
· Computer model (MNAM) forecasts of temperature and dew-point soundings
o 12Z Feb. 26, 2010
o 00Z Feb. 27
o 12Z Feb. 27
· Computer model (NAM) forecasts of temperatures at the 850 mb and 500 mb levels
12Z Feb. 26 at 850 mb / 12Z Feb. 26 at 500 mb00Z Feb. 27 at 850 mb / 00Z Feb. 27 at 500 mb
12Z Feb. 27 at 850 mb / 02Z Feb. 27 at 850 mb
Discussion: [Enter a description of how you determined your forecast. It should be detailed enough for someone else to reproduce it if necessary.]
Forecast:
Moisture supply: Yes (though it’s surprisingly close)
Frontal position: Yes
Atmospheric instability: Yes (though it’s a pretty close call)