National Overview - October 2002


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Top of Page October Temperatures

National Temperature Time Series
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The graph to the left shows monthly mean temperature averaged across the contiguous United States based on long-term data from the U.S. Historical Climatology Network (USHCN). The value for 2002 is estimated from preliminary Climate Division data using the first difference approach. October 2002 ranked as the 14th coldest October in the 1895 to present record. The preliminary nationally averaged temperature was 52.6° F (11.4° C) which was 2.2° F (1.2° C) below the long-term mean.
Much below average warmth occurred in 12 contiguous states in October. No statewide mean temperature records were set for the month, though Minnesota and South Dakota had their third coldest October since 1895 and both states had their coldest October since 1925. Only one state (Florida) had much above average temperatures for the month while 6 other southeastern states had significantly above average temperatures and 9 states out of the lower 48 states had near average temperatures.

As can be seen in a map of divisional temperature (below right), significantly warmer than average temperatures were evident in all but one Gulf coast division, as well as along the southeastern and mid-Atlantic coastal areas. This is in sharp contrast to the entire mid-section of the country from the Canadian border south to central Texas which had much below average temperatures. The pattern of warmth and cold in the contiguous U.S. in October broadly corresponded with the mean 500mb height and anomalies chart. This shows that well below normal 500mb heights existed across the upper Midwest/ northern Great Plains, which was associated with the much lower than average temperatures in October. It was the first October in four years that temperatures in Alaska were well above normal (more than 7°F) relative to the period 1971-2000. This was a reflection of the much above average 500mb height anomalies over the state of Alaska extending well down the west coast of Canada. It was the warmest October in Alaska since 1938, and it is only the 8th time on record that Anchorage has had no snow in October. (See the October North America snow summary page for further details)
mean 500mb height and anomalies
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State Temperature Ranks Click here for animated image
Regional Temperature Ranks for the
Contiguous U.S., October 2002
Region Rank
Northeast 24th coldest / 85th warmest
East North Central 5th coldest / 104th warmest
Central 28th coldest / 81st warmest
Southeast 95th coldest / 14th warmest
West North Central 3rd coldest / 106th warmest
South 26th coldest / 83rd warmest
Southwest 19th coldest / 90th warmest
Northwest 12th coldest / 97th warmest
West 51st coldest / 58th warmest

Top of Page Temperature Departures

The map to the right, based on over 500 airport stations, shows departures from the 1971-2000 normal temperatures for October 2002. Some of the largest widespread negative departures (greater than 7.5°F [4.2°C]) occurred in the Upper Mississippi Valley and Northern Great Plains. A new cold temperature record was set in Williston, ND on October 30th with a low of -9°F, breaking the old record of -3°F set in 1895 and equalled in 1991. A new record low maximum daily temperature was also recorded in Denver at 18°F on the 30th, and Marquette, Michigan had its coldest October on record with an average of only 37.9°F. This just falls below the previous record of 38°F set in 1988. See NCDC's Monthly Extremes web-page for more records.

Widespread positive temperature anomalies were limited to the southeastern quadrant of the country and the Gulf Coast. An animated map of daily temperature anomalies shows temperature variability throughout the month of October.
National Temperature Departures
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Top of Page August-October 2002

National Temperature Time Series
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The graph to the left shows mean temperature averaged across the contiguous United States based on long-term data from the U.S. Historical Climatology Network (USHCN). The value for August-October 2002 is estimated from preliminary Climate Division data using the first difference approach. August-October 2002 ranked as the 36th warmest such period in the 1895 to present record. The preliminary nationally averaged temperature for August-October 2002 was 64.6° F (18.1° C) which was 0.3° F (0.2° C) above the long-term mean.



Despite the cooler than average October in many states, statewide mean temperatures for the August-October period were warmer than average in the east and the Southwest with 5 eastern states (New Hampshire, Rhode Island, New Jersey, Vermont and Florida) having much above average temperatures for the 3 months. A further 23 states have significantly above average temperatures.

Significantly below average statewide mean temperatures occurred in 10 states with Montana average temperatures falling into the much below average category. When broken down by climate division (see map to the right), there are scattered divisions which were significantly warmer than average during this period in most eastern states althouth no record warm or cold divisional temperatures averaged over the August-October period occurred.

State Temperature Ranks
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500mb height and anomalies larger image
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Top of Page January-October 2002 (year-to-date)

National Temperature Time Series
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The graph to the left shows mean temperature averaged across the contiguous United States based on long-term data from the U.S. Historical Climatology Network (USHCN). The value for January-October 2002 is estimated from preliminary Climate Division data using the first difference approach. January-October 2002 ranked as the 14th warmest such period in the 1895 to present record. The preliminary nationally averaged temperature for January-October 2002 was 56.8° F (13.8° C) which was 1.1° F (0.6° C) above the long-term mean.

Statewide mean temperature for the January-October period was much above average for 18 states, with Delaware having its record warmest January-October in 108 years. Connecticut, New Jersey and Maryland all had their second warmest January-October on record.


Significantly above average statewide mean temperatures also occurred in 22 out of the remaining 30 contiguous states with only Montana averaging below normal temperatures for the year-to-date. Seven states had near average temperatures for January-October. When broken down by climate division, divisions in Maryland, Virginia, Delaware, New York, and Massachusetts reached record warmth for the January-October period, while cooler than average divisional temperatures were limited to Montana, Idaho and one division each in Wyoming, South Dakota, Texas, Oklahoma and Arkansas.

State Temperature Ranks
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Top of Page National Temperatures - November 2001-October 2002

National Temperature Time Series
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The graph to the left shows mean temperature averaged across the contiguous United States based on long-term data from the U.S. Historical Climatology Network (USHCN). November 2001-October 2002 ranked as the 4th warmest such period in the 1895 to present record. The preliminary nationally averaged temperature was 54.4°F (12.4°C) which was 1.6°F (0.9°C) above the long-term mean.
Record warmth occurred in six states (RI, CT, NJ, DE, MD and OH) averaged over the last twelve months. The pattern of state-averaged monthly temperature can be seen in the map to the right. Twenty-one other states ranked in the top ten warmest such periods. Only three states had near-average temperatures for November-October (MT, ID and WY). State Temperature Ranks
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Top of Page October Precipitation

National Precipitation Time Series
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The graph to the left is a time series depicting precipitation averaged across the contiguous U.S. Based upon preliminary precipitation data, October 2002 was much wetter than average, ranking 7th wettest - the most anomalously wet month since January 1999. There has been no significant trend in mean national October precipitation over the last century.
There was considerable regional variability in precipitation across the country. Nine states in the eastern half of the country (Mississippi, Texas, Louisiana, Kansas, Kentucky, West Virginia, Maryland, Delaware, and New Jersey) received much above average rainfall in October, while four states (California, Oregon, Washington and Idaho) received much below average rainfall this month. Louisiana, Texas and Delaware were second wettest on record for the month of October. Substantial drought alleviation has occurred in many eastern states and though states such as Colorado also received above average precipitation this month, it will still take many months of above average or near average rainfall to alleviate the long-term drought in that state and others in the Southwest and West. Some of the above-average rainfall in the eastern half of the country was a result of Hurricane Lili as it moved inland off the Gulf of Mexico on the 3rd. More details on October hurricanes and tropical storms can be found on the hurricane season page. State Precipitation Rankslarger image

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In Corpus Christi, Texas, on October 24th, a major storm which spawned several tornadoes led to the death of at least one person and injuries to over a dozen others. One tornado touched down in Del Mar college campus in the town and the path stretched a further two to three miles west and north of the campus. This followed on the heels of severe storms the previous day and Texas was hit with further storms later in the month mostly in the Houston area. These latter storms also produced at least one tornado and dumped up to 9 inches of rain in parts of the Houston Metro region.


Earlier in the month, on October 3rd, Hurricane Lili came ashore in western Louisiana bringing additional rain to areas already affected by Tropical Storm Isidore in September. More rainfall later in October led to a rank of second wettest October on record for Louisiana and Texas. Further details on flooding and rainfall in the Southeast and parts of the Gulf Coast are given on the Atlantic hurricane page, as they relate to landfalling tropical storms in October.

As the North American snow season got underway in October, some precipitation fell as snow, especially in the Northern Great Plains and the upper Midwest. More details of snowfall in October can be found on the snow season page

Regional Precipitation Ranks for the
Contiguous U.S., October 2002
Region Rank
Northeast 88th driest/ 21st wettest
East North Central 89th driest/ 20th wettest
Central 85th driest/ 24th wettest
Southeast 93rd driest/ 16th wettest
West North Central 55th driest/ 54th wettest
South 105th driest/ 4th wettest
Southwest 74th driest/ 35th wettest
Northwest 7th driest/ 102nd wettest
West 11th driest/ 98th wettest
National Precipitation Time Series
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The graph to the left is a time series depicting precipitation averaged across the primary hard red winter wheat belt. The growing season runs from October to February for the hard red winter wheat and preliminary data indicate that precipitation was much above average for the first month of the growing season in 2002.

Top of Page Precipitation Departures

The map to the right, based on more than 500 airport stations, shows October 2002 total precipitation as a percent of the 1971-2000 station normals. Above normal precipitation generally occurred in the South through the Mississippi Valley, the Tennessee/Ohio Valley regions, and much of the east coast with more than 190% of normal precipitation falling in some areas. A record wet month was recorded at several stations in Louisiana for example. A monthly total of 21.44 inches at Lake Charles, LA, broke the old record set in 1970 by 4.16 inches. Lafayette, LA also received 2.62 inches more than the previous old record, totalling 18.27 inches for October 2002.

Dryness extended across most of the West and Northwest where as little as 25% of normal precipitation was recorded. The northern Great Plains were also dry this month, with less precipitation than normal also occurring in the lower peninsula of Michigan and Florida. At Miami International Airport, a new monthly minimum rainfall record was set for October at 0.71 inches, breaking the previous record of 1.12 inches, set in 1925. More city and state extremes for the month can be found at NCDC's Extremes Page.
National Precipitation Departures
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Top of Page Last 3 months (August-October)

National Precipitation Time Series
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The graph to the left is a time series depicting precipitation averaged across the contiguous U.S. Based upon preliminary precipitation data, August-October 2002 was wetter than average, ranking 11th wettest in the last 108 years. This contrasts sharply with October of 2000 and 1999 and belies considerable regional variability as can be seen from the maps below.
State Precipitation Ranks larger image State Precipitation Ranks
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Much below average precipitation, over August-October, occurred in 5 western states (CA, NV, ID, OR, and WA) in 2002. Four other states (AZ, WY, NH, and ME) also received siginificantly below average precipitation. Six states received much above average rainfall with Mississippi having a record wet three months. Some of the rainfall over the three month period came in September from Tropical Storm Isidore and is discussed further on the Atlantic hurricane season web-page.
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Top of Page National Precipitation - January-October 2002 (year-to-date)

National Precipitation Time Series
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The graph to the left is a time series depicting precipitation averaged across the contiguous U.S. Based upon preliminary precipitation data, January-October 2002 was drier than average, ranking 28th driest in the last 108 such periods. The last 3 January-October periods have averaged below the long term mean precipitation.
The long term dryness becomes more apparent when looking at an average of the last 10 months. Record dryness occurred in 3 states (CO, CA and AZ) from January to October. The pattern of state-averaged year-to-date precipitation can be seen in the map to the right. Six other states ranked in the top ten driest such periods. More information on drought analysis for these states and others can be found on NCDC's Drought Pages. Two states (MN and WI) received much above average rainfall averaged over the last 10 months, with a third wettest January-October occurring in Wisconsin. State Precipitation Ranks
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Citing This Report

NOAA National Climatic Data Center, State of the Climate: National Overview for October 2002, published online November 2002, retrieved on October 24, 2014 from http://www.ncdc.noaa.gov/sotc/national/2002/10.