Record Warmth for the First Week of October

The first week of October has been unseasonably warm across much of the east coast and Great Lakes regions.  A highly amplified upper-level ridge in the middle to upper portions of the atmosphere has allowed very warm air most common along the Gulf Coast and Tennessee River Valley for this time of year to move up into the Southern Great Lakes region.  While the East was baking in very warm temperatures, a digging trough across the West Coast led to mountain snows across the Rockies and Pacific Northwest.

In Chicago, the average daily temperature for the first week of October was 70.1 degrees, tying it for the 3rd warmest first week in October since records began in 1872.  The warmest first week of October was recorded in 1879 when the average temperature was 72.6 degrees.

In Rockford, the average daily temperature for the first week of October was 70.7 degrees, making this the warmest first week of October ever recorded since records began in 1951.  This breaks the previous record of 66.6 degrees which was recorded in 1997.

These warm temperatures will be a distant memory come Wednesday as a series of frontal boundaries pass through the region, filtering much cooler air into the western Great Lakes.  Highs by Wednesday will only climb into the upper 50s with lake effect rain showers being possible by Thursday as the cooler air overspreads the lake.

The top five warmest first weeks of October are...

In Rockford...

Rank              Average Temp              Year
1                              70.7                        2007      
2                              66.6                        1997
3                              65.8                        1969
4/5                           64.6                        2005 and 1982 (tie)

 
In Chicago...

Rank              Average Temp              Year
1                              72.6                        1879      
2                              71.9                        1922
3/4                           70.1                        2007 and 1884 (tie)
5                              69.9                        1900

 
$$
 
GITRO


Return to News Archive

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.