All maps are surface temperature anomalies based on the 1981-2010 normals (in degrees Fahrenheit).
A maximum of 20 analogs are plotted on each map. The analogs are from 1950-2011.
Scroll to the bottom of the page for the methodology.
Other anomaly maps and related links:
AO (CPC – 1000mb)
AO (CPC – monthly)
NAO (CPC – seasonal)
PNA (CPC – seasonal)
EP/NP (CPC – seasonal)
WP (CPC – seasonal)
MJO (CPC – seasonal)
MJO and GWO (ESRL)
MJO 500mb maps (RaleighWx)
ENSO (CPC – seasonal)
ESRL main teleconnections page
EPO (old version): http://www.wxmidwest.com/epo/
EPO (CPC/new version): http://www.esrl.noaa.gov/psd/data/correlation/epo.data
*NOTE: QBO 50mb data only goes back to 1979.
Type of Plot: Average Anomaly
Contour Interval: 1
Lowest Contour: -6
Highest Contour: 6
Scale Plot Size: 100%
Due to the limitations of the mapping site, a maximum of 20 analogs were allowed for each map. Any years that were excluded are displayed beneath each map. In the positive/negative cases, the weakest monthly values were discarded. In the neutral cases, those furthest from 0.0 were discarded. When two or more analogs had the same value and at least one needed to be taken out of the final analog list, the earlier year(s) were discarded. In the neutral cases, if two or more analog years of the same absolute value needed to be discarded, one analog from each side of zero was taken out (using the earliest years first).
I chose to use these particular maps because it allows me to use up to 20 analogs with the new 30-year normals in Fahrenheit, and I have not been able to find a better map-making site that offers the ability to use more than 20 analogs.
The AO, NAO, PNA, EPO, WPO and PDO thresholds are defined as the following:
Positive: >= +0.5
Neutral: -0.5 to +0.5 exclusive
Negative: <= -0.5
The AMO thresholds are defined as the following:
Positive: >= +0.1
Neutral: -0.1 to +0.1 exclusive
Negative: <= -0.1
The QBO thresholds are defined as the following:
Positive: > 0.0
Negative: < 0.0