First Half of November – Warm and Dry

First Half of November

The first half of November in Illinois has been warm and dry, according to preliminary data from November 1-15, 2010. The statewide average temperature was 47.3 degrees, 2.9 degrees above normal. The statewide average precipitation was only 0.21 inches, only 13 percent of normal for the first half of November.

Past November’s in Illinois

  • The driest November on record was 1904 with 0.28 inches.
  • November 2007 was the 25th driest with 1.75 inches.
  • November 2008 was the 20th driest with 1.48 inches.
  • November 2009 was near-normal with 2.47 inches.
  • Normal state-wide precipitation for November is 3.34 inches.

The term “normal” refers to the 1971-2000 average.

Precipitation percent of normal for first half of November 2010
Precipitation (Percent of Normal) for the First Half of November 2010.

October Is Warm and Dry

So far, October in Illinois has been both warmer and drier than normal. As of October 19, the statewide average temperature was 59.8 degrees, 1 degree warmer than normal. The statewide average rainfall was only 0.22 inches, 12 percent of normal. See table below.
If this were July, the dryness would be a major source of concern. However, the impacts are much less in fall. In fact, the warm, dry weather aided in the maturing and harvesting of corn and soybeans. At the moment, the impacts are mostly focused on:

  • winter wheat – farmers are waiting on rains for germination;
  • landscaping – trees and shrubs may need more water before winter arrives;
  • fall color – I’ve noticed that the fall colors on trees and shrubs this year are muted with lots of shades of brown and yellow.

The NWS forecast shows a weather system moving through Illinois over the weekend. The potential rainfall amounts from this system range from 0.25 inches along the Wabash River in south-eastern Illinois to 1.25 inches in north-central Illinois. Another system is expected to move into the region on Tuesday/Wednesday. So the current dry weather may be short-lived.

                                Illinois
                        10/01/2010 to 10/19/2010
Climate          <------Temperature----->   <---------Precipitation--------->
Division         Actual   Normal      Dev   Actual   Normal     Dev   Percent
-----------------------------------------------------------------------------
Northwest          55.2     53.4      1.9     0.09     1.82    -1.73        5
Northeast          55.8     53.7      2.0     0.27     1.82    -1.56       15
West               57.6     56.3      1.4     0.10     1.90    -1.80        5
Central            56.7     55.7      1.0     0.22     1.86    -1.64       12
East               56.0     55.4      0.6     0.38     1.86    -1.48       20
West-southwest     58.0     57.5      0.5     0.13     1.72    -1.60        7
East-southeast     58.4     57.8      0.6     0.28     1.92    -1.65       14
Southwest          58.9     58.9      0.0     0.23     1.85    -1.63       12
Southeast          59.8     59.2      0.6     0.35     1.84    -1.49       19
State              57.3     56.3      1.0     0.22     1.84    -1.62       12
Dev means Deviation From Normal, Percent means Percent of Normal