Preliminary
Wyoming Monthly Climatology
April 2004

Statewide Summary

For parts of Wyoming, April 2004 was a complete reversal from record warmth and driest just a month earlier. Average temperatures ranged from 5 degrees F above normal over portions of extreme western and northeast Wyoming to near normal temperatures over a large portion of central Wyoming. Precipitation was normal or above normal across all but the NE part of the state where hardly any precipitation fell on Niobrara County. Statewide, Snow Water Equivalent (SWE) was about 54 percent of average. Last year by this time it was 76 percent. Snow cover based on remote satellite sensing, revealed some lower elevation snows as a result of the last week of April snowstorm. Soil moisture in early May showed some dryness over the western, northern, and eastern borders of Wyoming, with excess moisture over Fremont County.

Weather Summary: For the week ending Friday, April 9, temperatures averaged well above normal. This was the fourth consecutive week of above normal temperatures. Average temperatures ranged from 3.1 degrees above normal in Lander to 11 degrees above normal in Jackson. The highest temperature reported was 83 degrees in Newcastle while the lowest temperature was 22 degrees in Kaycee. Weekly highs ranged from the mid 60's to low 80's. Weekly lows ranged from the low 20's to low 30's. Precipitation fell across the entire State except for the Northeast and East Central. Most stations reported above normal precipitation and most received more than a quarter of an inch for the week. The most precipitation fell in Lander with 1.40 inch, Riverton with 1.35 inch, and Big Piney with 0.95 inch.

Weather Summary: For the week ending Friday, April 16, temperatures were mostly above normal. Average temperatures ranged from 4 degrees below normal in Archer to 6.4 degrees above normal in Jackson. The highest temperature reported was 76 degrees in Sheridan, Newcastle, and Redbird while the lowest temperature was 3 degrees in Laramie. Almost all stations reported below normal precipitation and received less than a tenth of an inch for the week. The most precipitation fell in Chugwater with 0.62 inch, Archer with 0.43 inch, and Lander with 0.34 inch.

Weather Summary: For the week ending Friday, April 23, temperatures were near normal. Average temperatures ranged from 3.1 degrees below normal in Evanston to 2.3 degrees above normal in Redbird. The highest temperature reported was 78 degrees in Torrington while the lowest temperature was 17 degrees in Big Piney. Weekly highs ranged from the mid 50's to high 70's. Weekly lows ranged from the high teens to low 30's. Most areas of the State received some precipitation during the week with most receiving below normal amounts. Most stations received from 0.10 to 0.30 inch for the week. The most precipitation fell in Sundance with 0.81 inch, Torrington with 0.54 inch, and Kaycee with 0.45 inch.

For the week ending Friday, April 30, temperatures were mostly below normal. Average temperatures ranged from 5.1 degrees below normal in Deaver to 3.4 degrees above normal in Jackson. The highest temperature reported was 82 degrees in Greybull, Sheridan, and Torrington while the lowest temperature was 16 degrees in Deaver. Weekly highs ranged from the mid 60's to low 80's. Weekly lows ranged from the mid teens to high 20's. Most areas of the State received some precipitation during the week with most receiving below normal amounts. Most stations received less than 0.30 inch for the week. The most precipitation fell in Lander with 1.18 inch, Sundance with 0.68 inch, and Riverton with 0.62 inch. Snow in western mountains helped replenish mountain snowpack.

Cheyenne

The average temperature in April was 44.3°F. This is 2.7°F above normal for the month. The maximum temperature for the month was 74°F on the 1st and the minimum of 15°F occurred on the 12th. Precipitation total of 1.24 inches is 80 percent of normal. Snowfall totaled 7.9 inches and is 81 percent of the long term mean.

  • past 30-days precipitation
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    Laramie

    The average temperature in April was 39.2°F. This is 2.0°F warmer than normal. The maximum temperature for the month was 68°F on the 1st, 17th, and 28th and the minimum for the month was 3°F occurring on the 12th. Precipitation total of 1.32 inches is 125 percent of normal. Snowfall totaled 7.5 inches and is 104 percent of the long term mean.

    Rawlins

    The average temperature in April was 41.9°F. This is 0.3°F warmer than normal. The maximum temperature for the month was 70°F on the 27th and the minimum for the month was 17°F occurring on the 11th. Precipitation total of 1.48 inches is 140 percent of normal. Snowfall totaled 8.6 inches and is 121 percent of the long term average.

    Rock Springs

    The average temperature in April was 43.5°F. This is 3.8°F warmer than normal. The maximum temperature for the month was 71°F on the 27th and the minimum for the month was 21°F occurring on the 11th. Precipitation total of 0.97 inch is 95 percent of normal. Snowfall totaled 5.8 inches and is 100 percent of the long term average.

    Evanston

    The average temperature in April was 41.4°F. This is 2.5°F warmer than normal. The maximum temperature for the month was 66°F on the 26th and the minimum for the month was 24°F occurring on the 20th. Precipitation total of 0.78 inch is 69 percent of normal. Snowfall totaled 8.8 inches and is 173 percent of the long term average.

    Big Piney

    The average temperature in April was 39.5°F. This is 3.1°F warmer than normal. The maximum temperature for the month was 69°F on the 26th the minimum for the month was 12°F occurring on the 11th. Precipitation total of 1.32 inches is 254 percent of normal. Snowfall totaled 8.2 inches and is 228 percent of the long term average.

    Lander

    The average temperature in April was 44.5°F. This is 0.6°F warmer than normal. The maximum temperature for the month was 74°F on the 27th and the minimum for the month was 23°F occurring on the 10th. A record high temperature was broken on the 1st (72 °F). Precipitation total of 3.48 inches is 168 percent of normal and represents the 14th wettest April since 1892. Snowfall totaled 17.4 and is 86 percent of the long term average.

  • past 30-days precipitation
  • past 30-days temperature
  • past 90-days precipitation
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    Riverton

    The average temperature in April was 45.7°F. This is 1.6°F warmer than normal. The maximum temperature for the month was 76°F on the 27th and the minimum for the month of 20°F occurred on the 10th. A record high temperature occurred on the 1st (72°F). Precipitation total of 2.32 inches is 230 percent of normal and ties with April 1945 as the 7th wettest April since 1918. Snowfall totaled 10.1 inches and is 187 percent of the long term average.

    Worland

    The average temperature in April was 48.8°F. This is 1.4°F warmer than normal. The maximum temperature for the month was 80°F on the 27th and the minimum for the month of 26°F occurred on the 10th. Precipitation total of 0.98 inch is 120 percent of normal. Snowfall totaled 6.6 inches and is 213 percent of the long term average.

    Sheridan

    The average temperature in April was 46.7°F. This is 2.8°F warmer than normal. The maximum temperature for the month was 82°F on the 27th and the minimum for the month of 16°F occurred on the 12th. Precipitation total of 0.67 inch is 38 percent of normal. Snowfall totaled 0.1 inch and is just 1 percent of the long term average.

  • past 30-days precipitation
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    Casper

    The average temperature in April was 44.4°F. This is 1.4°F warmer than normal. The maximum temperature for the month was 75°F on the 1st (daily record) and on the 27th and the minimum for the month of 15°F occurred on the 10th. Precipitation total of 1.16 inches is 76 percent of normal. Snowfall totaled 6.1 inches and is 50 percent of the long term average.

  • past 30-days precipitation
  • past 30-days temperature
  • past 90-days precipitation
  • past 90-days temperature
  • past 365-days precipitation
  • past 365-days temperature

    Torrington

    The average temperature in April was 48.5°F. This is 2.5°F warmer than normal. The maximum temperature for the month was 83°F on the 1st (daily record) and the minimum for the month of 17°F occurred on the 12th. Precipitation total of 0.88 inch is 52 percent of normal. Snowfall totaled 1.0 inch and is 30 percent of the long term average.

    Additional Stations:

    Buffalo
    Douglas
    Gillette
    Greybull

    This information was compiled by the Wyoming State Climatologist, University of Wyoming. For more information, contact Jan Curtis at (307) 766-6659. For periodic updates, visit http://www.wrds.uwyo.edu This site includes a searchable database for Wyoming climate and water. For additional daily and hourly climatology, click on historical at the bottom of the daily summary statistics. For Casper, Lander, and Riverton's Monthly F6 reports, see here and at the bottom of this webpage. Record daily temperatures are based on the period since 1948-9 for all cities unless otherwise noted.

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    Wyoming State Climatologist The Wyoming State Climatologist Office is funded by the Wyoming Water Development Commission

    WEBMASTER: stateclim@wrds.uwyo.edu
    Last reviewed or update: May 4, 2004

    		 Water Resources Data System