Current Hourly Comparison Map

Click to switch map above to read in F or C

The map above shows all stations in the United States for two temperature monitoring networks - The state of the art climate Reference Network in cyan, and the older GHCN/USHCN METAR based network in yellow, using the closest matched stations. The average for the USA for that hour for each network is shown on the right.

How to use this website

This website is useful for comparing absolute temperatures between the old climate monitoring networks (USCHN/GHCN) and the new modern state-of-the-art Climate Reference Network commissioned by NOAA in 2002 and finished in 2008. Press releases from NOAA don't make use of this new network when reporting "hottest or coldest ever" type claims when it comes to heat waves, high temperature records, low temperature records, monthly average temperatures, and yearly average temperatures. When claims are made about temperature, this website can give you an accurate report of hourly, daily, monthly, and annual temperature that is not biased by UHI and station siting issues of the old networks. For example, when a heat wave occurs, new records are often set. You can find the closest CRN station temperature and compare it to the station that set the record, to see if they are close.


Almost everyone is familiar with the daily high and low temperatures that are reported on the evening television news and given in the newspaper. The source of this data comes from NOAA's network of surface weather stations in the USA, known as the Cooperative Observer Network or COOP network. This network of stations consists of hourly and daily reporting stations that have records going  back to the formation of the US Weather Bureau in 1890. However, as shown in the peer reviewed paper Fall et all 2011, from the project of station surveys conducted by, the majority of these stations (~90%)have been compromised by urban encroachments, which can affect the high and low temperature records. To counter that, NOAA's National Climatic Data Center (NCDC) commissioned a new Climate Reference Network (CRN) in 2002, completed in late 2008, placing stations in pristine locations with optimal measurement environments, utilizing state of the art triple redundancy sensor systems.  The data this new network produces is of the highest quality, and perfect for scientific studies, but is not presented in way that lends itself to be as easily seen and understood as temperature data presented in newspapers and on the evening TV news. For the hourly map comparisons, the hourly METAR reporting network is used (

Therefore, the purpose of this website is to present numeric temperature data from both the old and new networks in easy to understand graphical form, side by side, which has never been done before. This is presented as a free public service, and is entirely privately funded and privately operated.


  • Hourly plotted data on US Maps of both the CRN and the COOP network, individually and side by side nearest station
  • Meteograms of both the CRN and the COOP network data for the current 24 hour period
  • Gradient based images showing warmest and coolest regions as described by both networks
  • Difference maps using gradients
  • Daily High and Low comparisons between networks  (coming in phase 2 - mid to late 2013)
  • Links to station metadata (coming in phase 2 - late 2013)
  • Google Earth integration (coming in phase 2  - late 2013)

Data Sources

All data presented on this website is from NOAA and NCDC data feeds for METAR and CRN data, delivered via satellite link using the NOAAport satellite data service. The base data values are not modified nor adjusted in any way, and are presented as is in graphic presentations. Unlike METAR hourly reporting data which is updated at the top of the hour for aviation purposes, due to quality control and other delays, the CRN data may be aged by NCDC up to three hours from the time they are viewed on this website. We have no control over this aging process, but we do attempt to ensure that all data presented on maps is synchronous in time. Please note the timestamps on all data products, given in UTC (Zulu) time.

Maps quick links:

Data acquisition times

Fixed Gradient Temps in F

Variable Gradient Temps in F

Difference Gradient Temps in F

Graphical Station Data:



Links of Interest: