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Department of Commerce Logo Climate of 2001 - April
U.S. Regional and Statewide Analyses

National Climatic Data Center, 11 May 2001

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Global Analysis / Global Regional / U.S. National / U.S. Regional / U.S. Drought / Extreme Events
Use these links to access detailed analyses of the Global and U.S. climate of April 2001.
Standard Regions for Temperature and Precipitation See larger image

 

Contents of This Section:

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Top of Page April 2001 Statewide Ranks

April Statewide Ranking Map for Temperature
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April 2001 temperatures were below normal in California, Oregon and Washington and generally above normal elsewhere in the nation. Illinois had its record warmest April in the 1895 to present record. The ten other states that ranked in the top ten warmest Aprils were
  • Missouri - second warmest
  • Arkansas and Kentucky - fourth warmest
  • Indiana - fifth warmest
  • Oklahoma, Tennessee and Ohio - sixth warmest
  • Nebraska - seventh warmest
  • Iowa - eighth warmest
  • West Virginia - tenth warmest
Despite this record warmth, twenty-seven of the forty-eight contiguous states fell in the cool third portion of the historical distribution for the six month period ending in April 2001.

In Alaska, temperatures averaged across the state were above normal for the ninth consecutive April. April ranked twentieth warmest out of 84 years of record.


April precipitation was generally characterized by wetness in the north central and western states and dryness in the central, southern and eastern states. Minnesota and South Dakota had their second wettest April in 107 years. Michigan experienced its third wettest and Idaho its tenth wettest April. Eleven other states fell into the wet third portion of the historical distribution. Despite a wet April, the Northwestern region ranked third driest for the year long period ending April 2001.

In contrast, April was an extremely dry month for many states.
  • New York and Maine - record driest
  • Vermont , New Hampshire and South Carolina - third driest
  • Texas - fourth driest
  • Arkansas and Virginia - sixth driest
  • Oklahoma and Florida - seventh driest
  • North Carolina and Connecticut - seventh driest
  • Kentucky, Massachusettes and New Jersey - eighth driest
  • Delaware - ninth driest
  • Louisiana and Tennessee - tenth driest.
    Nine additional states fell within the dry third portion of the historical distribution.
April Statewide Ranking Map for Precipitation
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Top of Page April Regional Highlights

Based upon preliminary data, April 2001 was the thirty-fifth coolest such month in the 1895 to present record for the Northwest region. Only six of the last fifteen Aprils were below the long-term mean. April Time Series for Coolest Region
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April Time Series for Warmest Region
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It was the fourth warmest April in the 1895 to present record for the Central region. However, ten of the last fifteen Aprils were below the long-term mean.

April 2001 was the third driest such month in the 1895 to present record for the Northeast region. This contrasts sharply with last April which was seventh wettest. The South and Southeast regions had extremely dry Aprils as well, ranking fourth driest and ninth driest, respectively. April Time Series for Driest Region
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April Time Series for Wettest Region
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It was the second wettest April for the East North Central region in 107 years. Above normal precipitation has been recorded in seven of the last eleven Aprils. Rapidly melting snowcover and above normal precipitation in the Upper Mississippi River Basin caused severe flooding. Areas of Minnesota received more than 400% of their normal rainfall. Some record totals were:
  • St.Cloud8.42 inches
  • Duluth8.18 inches
  • Rochester7.3 inches
  • Minneapolis7.0 inches


View a temperature or precipitation time series for any region from the table below. Click on a region's precipitation or temperature rank to view the 1895-2001 time series.

Region Precipitation Temperature
Northeast 3 76
East North Central 106 94
Central 20 104
Southeast 9 81
West North Central 98 82
South 4 96
Southwest 79 86
Northwest 89 35
West 85 44

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March through April 2001 precipitation has averaged drier than normal over much of the Primary Corn and Soybean agricultural belt. Many areas in the belt had record dryness for April. The growing season for the Primary Corn and Soybean Belt runs from March through September. For further agricultural information visit the Weekly Weather and Crop Bulletin. Corn and Soybean Region Precipitation Map
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Top of Page April Precipitation and Temperature Ranks, Extremes and Normals

Table 1 shows precipitation and temperature ranks for each of the 9 regions and the nation for April 2001, the two months of March-April 2001, the six months of November 2000-April 2001, and the past 12 months, May 2000-April 2001.

           TABLE 1.  PRECIPITATION AND TEMPERATURE RANKS, BASED
                     ON THE PERIOD 1895-2001.  1 = DRIEST/COLDEST,
                     107 = WETTEST/WARMEST FOR APR 2001,
                     107 = WETTEST/WARMEST FOR MAR-APR 2001,
                     106 = WETTEST/WARMEST FOR NOV 2000-APR 2001,
                     106 = WETTEST/WARMEST FOR MAY 2000-APR 2001.

                                APR    MAR-APR   NOV 2000-  MAY 2000-
            REGION              2001     2001    APR 2001   APR 2001
            ------              ----  ---------  ---------  ---------

                      PRECIPITATION:

           NORTHEAST              3       43         12         40
           EAST NORTH CENTRAL   106       83        102         87
           CENTRAL               20        7         12         29

           SOUTHEAST              9       70         31          9
           WEST NORTH CENTRAL    98       83         97         52
           SOUTH                  4       35         88         48

           SOUTHWEST             79       75         65         64
           NORTHWEST             89       68          2          3
           WEST                  85       61         19         29

           NATIONAL              27       46         29         24

                      TEMPERATURE:

           NORTHEAST             76       48         44         31
           EAST NORTH CENTRAL    94       73         38         48
           CENTRAL              104       76         26         34

           SOUTHEAST             81       50         29         36
           WEST NORTH CENTRAL    82       83         27         52
           SOUTH                 96       61         12         49

           SOUTHWEST             86       92         56         95
           NORTHWEST             35       71         27         45
           WEST                  44       76         58         75

           NATIONAL              95       80         20         67

It should be emphasized that all of the temperature and precipitation ranks and values in Tables 1 through 3 are based on preliminary data. The ranks will change when the final data are processed. National ranks and values are based on a combination of USHCN and divisional data.


Top of Page Table 2 shows historical extremes for April, the 1961-1990 normal, and the April 2001 value for each of the 9 regions and the contiguous U.S. for precipitation and temperature.
                                     PRECIPITATION (INCHES)
                                   DRIEST     WETTEST   NORMAL  2001
               REGION            VALUE YEAR VALUE YEAR   PCPN   PCPN
               ------            ---------- ----------  ------ ------

              NORTHEAST           0.71 1915  6.56 1936   3.14   4.76
              EAST NORTH CENTRAL  0.21 1910  3.50 1977   1.89   0.82
              CENTRAL             0.55 1910  6.91 1897   3.92   2.12

              SOUTHEAST           1.54 1910  8.89 1980   4.75   7.11
              WEST NORTH CENTRAL  0.39 1994  2.10 1987   1.02   0.61
              SOUTH               0.89 1966  6.28 1973   2.83   3.46

              SOUTHWEST           0.20 1956  2.90 1905   1.02   1.14
              NORTHWEST           0.58 1965  5.46 1904   2.72   2.41
              WEST                0.09 1914  6.28 1907   2.23   1.70

              NATIONAL            0.91 1910  3.89 1973   2.47   2.52*

                                  * PRELIMINARY VALUE, CONFIDENCE
                                    INTERVAL + OR - 0.29 INCHES

                                     TEMPERATURE (DEGREES F)
                                   COLDEST    WARMEST   NORMAL  2001
               REGION            VALUE YEAR VALUE YEAR   TEMP   TEMP
               ------            ---------- ----------  ------ ------

              NORTHEAST           25.1 1916  42.5 1946   33.4   30.7
              EAST NORTH CENTRAL  18.8 1960  42.2 1910   29.9   28.0
              CENTRAL             29.0 1960  53.0 1946   43.0   39.6

              SOUTHEAST           44.9 1960  63.2 1945   54.7   52.8
              WEST NORTH CENTRAL  19.1 1965  43.4 1910   31.2   32.5
              SOUTH               43.7 1915  62.6 1907   53.6   50.5

              SOUTHWEST           35.6 1917  49.0 1910   41.9   44.2
              NORTHWEST           31.0 1917  46.0 1934   38.6   40.6
              WEST                39.5 1897  55.0 1934   46.3   50.2

              NATIONAL            47.6 1920  56.2 1981   51.7   54.2

 
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Top of Page Water Year River Basin Statistics, October 2000-April 2001

Table 3 shows statistics for selected river basins: Precipitation rankings are for October 2000-April 2001, where 1 = driest, and 106 = wettest, based on the period 1895 to 2001. Also shown is the areal percent of the basin experiencing severe or extreme long-term (Palmer) drought, and areal percent of the basin experiencing severe or extreme long-term (Palmer) wet conditions, as of April 2001.
                                        PRECIPITATION  % AREA  % AREA
          RIVER BASIN                       RANK        DRY     WET
          -----------                   -------------  ------  ------

          MISSOURI BASIN                     93          8.9%    6.9%
          PACIFIC NORTHWEST BASIN             2         23.6%    1.8%
          CALIFORNIA RIVER BASIN             26          0.0%    0.0%

          GREAT BASIN                        78          0.0%    0.0%
          UPPER COLORADO BASIN               73          0.0%    0.0%
          LOWER COLORADO BASIN               89          0.0%   18.3%
          RIO GRANDE BASIN                   96          0.0%   11.2%

          ARKANSAS-WHITE-RED BASIN           97          0.0%    6.7%
          TEXAS GULF COAST BASIN             93          0.0%    0.0%
          SOURIS-RED-RAINY BASIN             99          0.0%   63.4%
          UPPER MISSISSIPPI BASIN            80          0.0%   15.3%

          LOWER MISSISSIPPI BASIN            57          6.6%    0.0%
          GREAT LAKES BASIN                  16          0.0%    0.0%
          OHIO RIVER BASIN                    3         20.6%    0.0%
          TENNESSEE RIVER BASIN              16          0.0%    0.0%

          NEW ENGLAND BASIN                  14          0.0%    0.0%
          MID-ATLANTIC BASIN                  5          0.0%    0.0%
          SOUTH ATLANTIC-GULF BASIN          24         25.3%    0.0%


The river basin regions are defined by the U.S. Water Resources Council.

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Top of Page For more information, refer to ...

References:

Thomas R. Karl and Albert J. Koscielny, 1982: "Drought in the United States: 1895-1981." Journal of Climatology, vol. 2, pp. 313-329.

Thomas R. Karl and Walter James Koss, 1984: "Regional and National Monthly, Seasonal, and Annual Temperature Weighted by Area, 1895-1983." Historical Climatology Series 4-3, National Climatic Data Center, Asheville, NC, 38 pp.

Historical precipitation and temperature ranking maps are also available on the Internet courtesy of the Climate Prediction Center.

NOAA works closely with the academic and scientific communities on climate-related research projects to increase the understanding of El Niño and improve forecasting techniques. NOAA's Climate Prediction Center monitors, analyzes and predicts climate events ranging from weeks to seasons for the nation. NOAA also operates the network of data buoys and satellites that provide vital information about the ocean waters, and initiates research projects to improve future climate forecasts. The long lead climate outlooks are available from the Climate Prediction Center.

Additional information about current climate anomalies can be found at the respective Web Pages of the Southern Regional Climate Center, Western Regional Climate Center, Midwest Regional Climate Center, Southeast Regional Climate Center, High Plains Regional Climate Center, and the Northeast Regional Climate Center.

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Top of Page For all climate questions other than questions concerning this report, please contact the National Climatic Data Center's Climate Services Division:

Climate Services Division
NOAA/National Climatic Data Center
151 Patton Avenue
Asheville, NC 28801-5001
fax: 828-271-4876
phone: 828-271-4800
email: questions@ncdc.noaa.gov
For further information on the historical climate perspective presented in this report, contact:

Jay Lawrimore
NOAA/National Climatic Data Center
151 Patton Avenue
Asheville, NC 28801-5001
fax: 828-271-4328
email: Jay.Lawrimore@noaa.gov

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