|
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.
|
Larger Map
|
 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.
|
larger image
|
larger image
|
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.
|
larger image
|
larger image
|
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.
| 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.
|
larger image
|
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.
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
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.
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.
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
 NCDC / Climate Monitoring / Climate of 2001 / April / Search / Help
http://lwf.ncdc.noaa.gov/oa/climate/research/2001/apr/us_regional.html
Downloaded Saturday, 05-Jul-2008 20:32:37 EDT
Last Updated Tuesday, 12-Jul-2005 09:59:19 EDT by Dimitri.H.Chappas@noaa.gov
Please see the NCDC Contact Page if you have questions or comments.
|
See larger image
