Weather Observations Spring 2016 Kyle Imhoff

Weather Observations There are many ways in which atmospheric scientists observe the weather, both at the surface and in the upper levels of the atmosphere Surface weather stations Automated reporting and human-recorded Radar Satellite Weather balloons (radiosondes) Aircraft (dropsondes) Mobile weather stations (trucks, aircraft, etc.)

Surface Weather Stations Two primary observational networks for surface weather conditions Automated network – regulated by the Federal Aviation Administration (FAA) and National Weather Service (NWS) Volunteer observer network – regulated by NWS solely Known as the Cooperative Observer Network (COOP)

Hourly Weather Reports (FAA) Over 1300 airports take weather observations each hour (or more frequently) Below is an example of automated output, known as a METAR (Meteorological Terminal Aviation Routine Weather Report): METAR KABC 121755Z AUTO 21016G24KT 180V240 1SM -RA BR BKN015 0VC025 06/04 A2990 RMK A02 PK WND 20032/25 WSHFT 1715 VIS 3/4V1 1/2 RAB07 POOO3 6OOO9 T00640036 10066 21012 58033

Weather Observer Network (COOP) Report once a day (at 12z or 7am/8am EST) Almost all report 24-hr precipitation amount Most report max/min temp and snowfall Some locations have historical records for 100 years+ Backbone of nation’s climate records

Network of “Best” COOP Sites USHCN (US Historical Climate Network) Pick COOP stations that have consistent records over many decades

Other Surface Weather Networks Numerous additional automated/weather observer networks CoCoRaHS (like COOP, but just precip/snow) DOT DoD USDA EPA Etc., etc.

Observations Satellite Radar Two types: Polar Orbiting Geostationary very high resolution only twice a day Geostationary lower resolution nearly continuous 3 basic channels VIS (visible) IR (infrared) WV (H2O) Radar Surface based uses microwave energy sent in rapid pulses to detect wind & precip Network across USA WSR88D located at 125 sites including Alaska, Hawaii, Guam and PR Displays returns of precip & wind in a 250 mile radius of site refreshed every 6 min. Can now aid in determining precipitation type

Weather Balloons (Radiosondes) Released twice a day at NWS offices across the country Crucial to understanding atmospheric conditions at higher levels in the atmosphere Very important for data ingest to computer weather models

Aircraft (Dropsondes) Provides an additional observational tool for upper-level atmospheric conditions One of the primary uses for this information is supplementary observations from upper levels within a tropical storm/hurricane

Mobile Platforms Not a reference to mobile-phone applications Relatively new technology Provides a unique perspective in weather observations – cross-sections over geographical regions for one variable (e.g. temp) Map showing trucking routes containing weather data

Time Series from Vehicle