Designed and Managed by Prof. Alan C. Czarnetzki
Department of Earth Science
University of Northern Iowa
Welcome!
This contest is intended to help you experience the process of
constructing a weather forecast. Carefully read each strategy and use the
links to obtain products that will provide guidance as you construct your
forecast.
Enter your forecast of the surface temperature advection that will be observed over ALO at 12 UTC tomorrow morning and 00 UTC tomorrow evening.
Guidance Links:
NGM Eta AVN Many Models NCEP Model Analyses and Forecasts
HPC Model Diagnostics,
Biases, Verification Model Comparison from UW CAPS
Verification: Forecasts will be verified by examining the relation
between the geostrophic wind as revealed by the mean sea level isobars and the
1000 mb to 500 mb thickness field at the valid times of your forecast.
Your forecast of temperature advection:
A) I predict that _____ advection will occur at 12 UTC tomorrow morning. (Choose one of the following.)
warm air
cold air no significant
B) I predict that _____ advection will occur
at 00 UTC tomorrow evening. (Choose one of the following.)
warm air cold air no significant
Enter your forecast for a frontal passage over ALO between 12 UTC tomorrow morning and 00 UTC tomorrow evening.
Guidance Links:
Analyzed Surface Maps Forecast Surface Maps NCEP Model Analyses and Forecasts
Verification: Your forecasts will be verified against the standard surface analyses for the valid period.
Your forecast for frontal passage:
I predict that __________ will pass over ALO between 12 UTC tomorrow morning and 00 UTC tomorrow evening.
no front a cold front a warm front an occluded front
Enter your forecast of cloud cover in ALO for 12 UTC tomorrow morning and 00 UTC tomorrow evening. Your choices are SKC/CLR (clear; no clouds), FEW (few clouds; 1 to 2 eighths of the sky is covered), SCT (scattered; 3 to 4 eighths cloud cover), BKN (broken; 5 to 7 eighths cloud cover), and OVC (overcast; all the sky is covered).
Guidance Links:
Current NWS MOS Products RAP Models Page
Verification: Your forecasts will be verified against observed sky conditions at the valid times.
Your forecast of sky conditions at:
A) 12 UTC tomorrow morning:
SKC/CLR FEW SCT BKN OVC
B) 00 UTC tomorrow evening:
SKC/CLR FEW SCT BKN OVC
Several factors favor the occurrence of precipitation. These include adequate moisture, a lifting mechanism, and instability. Determine which of these three factors you feel will favor precipitation in ALO at 12 UTC tomorrow morning and 00 UTC tomorrow evening.
Guidance Links for Moisture:
NGM Eta AVN Many Models NCEP Model Analyses and Forecasts
Verification: Your forecast will be verified against the NGM's analysis of the average relative humidity in the layer between 850 mb and 500 mb at the valid times. If this value is at least 70%, it will be assumed that moisture favors precipitation.
Your forecast:
A) Moisture will favor precipitation at 12 UTC tomorrow morning.
Yes No
B) Moisture will favor precipitation at 00 UTC tomorrow evening.
Yes No
B) Lift
Guidance Links for Large-Scale Lift:
NGM Eta AVN Many Models NCEP Model Analyses and Forecasts
Verification: Your forecasts will be verified against the ETA's analysis of 700 mb vertical velocity at the valid times. If the vertical velocity is positive, it will be assumed that large-scale lift favors precipitation.
Your forecast:
A) Large-scale lift will favor precipitation at 12 UTC tomorrow morning.
Yes No
B) Large-scale lift will favor precipitation at 00 UTC tomorrow evening.
Yes No
C) Instability
Guidance Link for Instability:
Verification: Your forecast will be verified against the observed temperature decrease between 850 mb and 500 mb at the valid times. If the temperature decrease is at least 25oC, it will be assumed that instability favors precipitation.
Your forecast:
A) Instability will favor precipitation at 12 UTC tomorrow morning.
Yes No
B) Instability will favor precipitation at 00 UTC tomorrow evening.
Yes No
Assuming that precipitation will occur in ALO, enter your forecast of the form it will take at 12 UTC tomorrow morning and 00 UTC tomorrow evening.
Guidance Links:
NGM Eta AVN Current NWS MOS Products
Many Models NCEP Model Analyses and Forecasts
Verification: If precipitation occurs in ALO, your forecast will be verified against the precipitation type actually observed. If no precipitation occurs, this section of the contest will not be graded.
Your forecast of precipitation type at:
A) 12 UTC tomorrow morning:
rain/freezing rain snow/frozen precip.
B) 00 UTC tomorrow evening:
rain/freezing rain snow/frozen precip.
Enter your forecast of the surface wind direction and speed for ALO at 12 UTC tomorrow morning and 00 UTC tomorrow evening.
Guidance Links:
RAP Models Page Current NWS MOS Products
Verification: Your forecast will be verified against the wind direction and speed observed in ALO at the valid times. Refer to the Strategy link to convert expected wind direction in degrees to a compass direction.
Your forecast of wind direction and speed (knots):
A) at 12 UTC tomorrow morning:
Direction:
light and variable N NE E SE S SW W NW
Speed:
lt. and var. (0-4) 5-9 10-14 15-19 20-24 25 and above
B) at 00 UTC tomorrow evening:
Direction:
light and variable N NE E SE S SW W NW
Speed:
lt. and var. (0-4) 5-9 10-14 15-19 20-24 25 and above
Enter your forecast of the maximum and minimum temperatures that will occur between midnight tonight and midnight tomorrow night at ALO.
Guidance Links:
ALO Climo. Current NWS MOS Products Iowa RAP Surface Data Univ. of Wyoming
Verification: Your forecasts will be verified against the actual 24-hour high and low temperatures reported for ALO.
Your forecasts of high and low temperatures:
A) High:
B) Low:
Enter your forecast of the probability that precipitation of some kind measuring at least a TRACE" will be observed in ALO "tonight" (here defined as the period from 00 UTC this evening to 12 UTC tomorrow morning) and "tomorrow" (here defined as the period from 12 UTC tomorrow morning to 00 UTC tomorrow evening).
Guidance Links:
Current NWS MOS Products Iowa RAP Surface Data RAP Radar Data
Verification: Your forecasts of POP for ALO will be verified against observations of precipitation during the forecast periods.
Your forecasts for the probability of precipitation:
A) POP valid for 00 to 12 UTC ("tonight"):
B) POP valid for 12 to 00 UTC ("tomorrow"):
The End!