An Overview of the AMS ChapterIowa Forecast Contest AFC

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An Overview of the AMS Chapter/Iowa Forecast
Contest (AFC)

• Jeremy Grams

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AMS/Iowa Forecast Contest

• An advanced forecast contest for ISU.
• Forecast different elements.
• Public Max/Min Temps, POPs, QPF, QSF
• Aviation Ceilings, Visibilities, and Winds.
• Forecast for various days (from day 1 to 7).
• Square the error scoring system.
• Forecast again all MOS and the NWS.
• Forecast across central Iowa.
• 4 days per week (Mon. - Thurs.)
• Must complete 12 of the 21, 2-week 1-week
  periods.
• Year-end tournament in late summer.

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Schedule

• Sep. 12th - Sep. 22nd Des Moines Day 1
  T/P/Q
• Sep. 26th - Oct. 6th Ames
  Day 2 T/P/Q
• Oct. 10th - Oct. 20th Ottumwa
  Day 2.5 T/P/Q
• Oct. 24th - Nov. 3rd Estherville Day
  7/6/5/4 T/P
• Nov. 7th - Nov. 17th Marshalltown Day 1
  T/P/Q/S
• Nov. 28th - Dec. 8th Waterloo Day 1
  W/C/V
• Dec. 19th - Dec. 22nd AMW DSM Day 2 T/P/Q/S
• Jan. 9th - Jan. 19th Mason City Day 1
  T/P/Q/S
• Jan. 23rd - Feb. 2nd Lamoni Day 5 T/P
• Feb. 6th - Feb. 16th Marshalltown Day
  4/3/2/1 T/P/Q/S
• Feb. 20th - Mar. 2nd Ottumwa Day 1 W/C/V

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Schedule

• Mar. 6th - Mar. 9th Mason City Day 1
  2 T/P/Q/S
• Mar. 20th - Mar. 30th Des Moines Day
  2 T/P/Q/S
• Apr. 3rd - Apr. 13th Marshalltown Day
  7/6/5/4 T/P
• Apr. 17th - Apr. 27th Estherville Day 1 T/P/Q
  
• May 8th - May 11th ALO OTM Day 1 T/P/Q
• May 15th - May 25th Lamoni Day 2.5 T/P/Q
• Jun. 5th - Jun. 15th Mason City Day 1 W/C/V
• Jun. 19th - Jun. 29th Ames Day 1 T/P/Q
• Jul. 10th - Jul. 20th Des Moines Day 4/3/2/1
  T/P/Q
• Jul. 24th - Aug. 3rd Waterloo Day 2 T/P/Q
• Aug. 7th - Aug. 17th Tournament

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Forecast Interval

• Forecast submitted by 2330z (630 pm CDT).
• Temperature
• Min between 01z to 14z.
• Max between 13z to 01z.
• Precipitation
• 00z to 12z and 12z to 00z.
• Wind Speed
• Highest sustained from 03z to 18z.
• Ceiling and Visibility
• Minimum prevailing between 03z to 18z.

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Forecast Elements

• All elements but temperature are categorized.
• POP Cat 0 to 10 (0-100).
• QPF QSF
• 0 -- 0.00" or trace 0 -- 0.0" or trace
  
• 1 -- 0.01 to 0.09 1 -- 0.1 to 1.9"
• 2 -- 0.10 to 0.24" 2 -- 2.0 to 3.9"
• 3 -- 0.25 to 0.49" 4 -- 4.0 to 5.9"
• 4 -- 0.50 to 0.99" 6 -- 6.0 to 7.9"
• 5 -- 1.00 to 1.99" 8 -- gt 8.0"
• 6 -- gt 2.00"

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Forecast Elements

• HWS LRC
• 1 -- 0 to 3 kts 1 -- lt 200 feet
• 2 -- 4 to 7 kts 2 -- 200 to 400 feet
• 3 -- 8 to 11 kts 3 -- 500 to 900 feet
• 4 -- 12 to 15 kts 4 -- 1000 to 1900 feet
• 5 -- 16 to 19 kts 5 -- 2000 to 3000 feet
• 6 -- 20 to 23 kts 6 -- 3100 to 6500 feet
• 7 -- 24 to 27 kts 7 -- 6600 to 12000 feet
• 8 -- gt 28.0 kts 8 -- gt 12000 feet or no
  ceiling
• LRV
• 1 -- lt 0.5 miles 5 -- 3.0 to 5.4 miles
• 2 -- 0.5 to 0.9 miles 6 -- 5.5 to 6.4 miles
• 3 -- 1.0 to 1.9 miles 7 -- gt 6.5 miles
• 4 -- 2.0 to 2.9 miles

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Verification

• All sites verified at airports with NWS/FAA ASOS.
• POP
• Verified as 0 for no precip or trace.
• Verified as 100 for 0.01 or greater.
• Snowfall will be at the official NWS coop site
  for that city.
• Anytime snow or sleet is reported by ASOS.
• NWS coop sites will be used.

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Verification

• Highest wind speed
• Highest sustained speed reported at any hourly or
  special observation.
• Gusts are not verified.
• Lowest ceiling and visibility
• Any observation (hourly or special)
• If variable, will use only prevailing.

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Scoring

• Squaring the errors for differentiation.
• Divide by normalization factor.
• Temperature
• 1 degF 1 errors divide by 5 0.2
• 5 degF 25 errors divide by 5 5.0
• 15 degF 225 errors divide by 5 45.0
• POP
• 10 1 errors divide by 2.5 0.4
• 50 25 errors divide by 2.5 10.0
• 100 100 errors divide by 2.5 40.0

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Scoring

• QPF/QSF
• 1 cat 1 errors divide by 0.5 2.0
• 3 cat 9 errors divide by 0.5 18.0
• 5 cat 25 errors divide by 0.5 50.0
• HWS/LRC/LRV
• 1 cat 1 errors divide by 1 1.0
• 3 cat 9 errors divide by 1 9.0
• 6 cat 36 errors divide by 1 36.0

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Normalized Scores

• All scores are normalized at the end of the
  period.
• Since not all forecasters will attempt the same
  cities.
• Normalized score
• (raw score -mean)10/S 80.
• Mean is average of all forecasts.
• S is standard deviation of all forecasts.
• The lower your score is, the more accurate you
  are relative to other forecasters.

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Absences

• Must forecast 6 of the 8 days in a period.
• Miss a forecast
• Assigned consensus MOS.
• If you know you will be absent.
• You can email me with the specific MOS or combo
  you want.

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MOS

• GFS
• MAV short-term
• MEX long-term
• MEC long-term ensemble
• Eta
• MET short-term
• NGM
• FWC short-term
• CMO MAVMET
• Consensus of above models.

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NWS

• Their forecasts through 2340z.
• Point Forecast Matrix (PFM).
• For Temperature, POP, QPF, QSF, and HWS.
• Terminal Aerodrome Forecast (TAF).
• For HWS, LRC, and LRV.

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Year-End Tournament

• Head-to-head battles between forecasters.
• Will play only against another forecaster.
• Winners move on to play other winners, while
  losers play other losers.
• Seeding based on regular season scores.

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How to Sign Up

• Will need to register with username and password.
• http//www.meteor.iastate.edu/miraje/AFC/
• Click the Add Yourself link on the top of the
  page.
• http//www.weatherforecastforyou.com/AFC/add.php
• Please keep your username to 8 characters and all
  lower-case.
• Your password will be encrypted in a database, so
  if you forget your password send me an email.

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Questions

• Web Site
• http//www.meteor.iastate.edu/ams/
• Click on AMS Forecast Contest link
• Email
• Jeremy Grams (jgrams_at_iastate.edu)