Module: NOAA

Defined in:
lib/noaa.rb,
lib/noaa/station.rb,
lib/noaa/version.rb,
lib/noaa/forecast.rb,
lib/noaa/forecast_day.rb,
lib/noaa/http_service.rb,
lib/noaa/station_writer.rb,
lib/noaa/current_conditions.rb

Overview

The NOAA singleton provides methods to conveniently access information from the NOAA weather feed. For the most part, NOAA.current_conditions and NOAA.forecast will be the only entry point into the NOAA API you will need; one exception is discussed below.

Defined Under Namespace

Classes: CurrentConditions, Forecast, ForecastDay, HttpService, Station, StationWriter

Constant Summary collapse

VERSION = 
'0.2.4'

Class Method Summary collapse

Class Method Details

.current_conditions(lat, lng) ⇒ Object

Retrieve the current weather conditions for a given latitude and longitude. Returns an instance of NOAA::CurrentConditions.

NOAA.current_conditions(37.989, -77.507)  #=> NOAA::CurrentConditions encapsulating current conditions at this point

Note: This method parses the stored list of all weather stations in the US and then finds the closest one to the given coordinates, as the NOAA XML API only takes a weather station ID as input. Clearly, this is an expensive operation; if your application needs to repeatedly request conditions for the same point, you will be much better off determining the current station once using NOAA::Station.closest_to, storing the station ID, and then passing it into NOAA.current_conditions_at_station when you need to get the latest conditions.



34
35
36
 
# File 'lib/noaa.rb', line 34

def current_conditions(lat, lng)
  current_conditions_at_station(Station.closest_to(lat, lng).id)
end

.current_conditions_at_station(station_id) ⇒ Object

Retrieve the current weather conditions for a given weather station ID. Returns an instance of NOAA::CurrentConditions.

NOAA.current_conditions_at_station('KNYC')  #=> NOAA::CurrentConditions encapsulating current conditions in Central Park

See discussion above regarding why this method is often preferable to simply calling #current_conditions.



46
47
48
 
# File 'lib/noaa.rb', line 46

def current_conditions_at_station(station_id)
  CurrentConditions.from_xml(HttpService.new.get_current_conditions(station_id))
end

.forecast(num_days, lat, lng) ⇒ Object

Retrieve daily forecast information for a given latitude and longitude. Returns an instance of NOAA::Forecast.

NOAA.forecast(4, 37.989, -77.507)  #=> NOAA::Forecast containing next four days of forecast data for given coordinates

Note: The NOAA updates this data no more than once an hour, and asks that users of the API not request the forecast for a given location more frequently than that. For more information, please see www.nws.noaa.gov/xml/#frequency



59
60
61
 
# File 'lib/noaa.rb', line 59

def forecast(num_days, lat, lng)
  Forecast.from_xml(HttpService.new.get_forecast(num_days, lat, lng))
end