1996 Weather Report

Malheur Experiment Station

Information for Sustainable Agriculture

1996 WEATHER REPORT

Erik Feibert, J. Mike Barnum, and Clint Shock
Malheur Experiment Station
Oregon State University
Ontario, Oregon

Introduction

Daily observations of air temperature and precipitation have been recorded at the Malheur Experiment Station since July 20, 1942. Installation of additional equipment in 1948 allowed for evaporation and wind measurements. Evaporation is measured as inches of water evaporated from a standard 10-Inch deep by 47.5- inch diameter pan over 24 hours. Wind run is measured as total wind movement in miles over a 24 hour period measured at 24 inches above ground level. A soil thermometer was added in 1967. A biophenometer to monitor degree days, and pyranometers, to monitor solar and photosynthetically active radiation, were added in 1985.

Since 1962. daily readings from the station have been reported to the U.S. Department of Commerce. Environmental Science Service Administration, and the National Weather Service. Each day the 6:00 a.m. air temperature, preceding 24-hour air and soil temperature extremes, and 24-hour accumulated precipitation are recorded and transmitted to radio station KSRV in Ontario. KSRV then conveys this information, along with their own daily readings. to the U.S. Weather Station in Boise, Idaho. During the irrigation season (April -October), evaporation, wind, and water temperature are also monitored and reported.

On June 1. 1992. in cooperation with the U.S. Bureau of Reclamation, a fully automated weather station, connected by satellite to the Northwest Cooperative Agricultural Weather Network (AgriMet) computer in Boise. Idaho, began transmuting data from the Malheur Experiment Station. The automated station monitors air temperature, relative humidity, dew point temperature, precipitation, wind run, wind speed, wind direction. Solar radiation, and soil temperature at 8-inch and 20-inch depths. Stored date is transmitted via satellite to the Boise computer every 4 hours. The database may be accessed via computer modem. Daily Malheur County crop water-use estimates, which are based on data from this automated weather station, are also available by modem.

1996 Weather

Total precipitation was 12.69 inches for the year. exceeding the 10-year and 54-year station averages by 30 percent and 20.3 percent, respectively (Table 1). The months of March, April, and May had precipitation totals above both the 10-year and 54-year means (Table 1. Figure 1).
Total snowfall for 1996 was 14.5 inches, 27.5 and 26.1 percent below the 10-year and 54-year means, respectively (Table 2). Mean monthly maximum air temperatures for July and August were 94 and 91 °F, above the long term station means (Table 3, Figure 2). The total accumulated growing degree days (50-86 °F) was slightly lower than the 10-year mean (Table 4, Figure 3). The total number of degree days in the 86-104 °F range for July was 42 percent above the 70-year mean (Table 5).

The mean monthly maximum and minimum 4-inch soil temperatures were close to the 10-year and 54-year means (Table 6).

Total pan-evaporation for April through October was 56.77 inches, below the 10-year mean and above the 48-year mean (Table 7).

April, May, June, August, September, and October were windier than the 10-year and 54-year means (Table 8).

The last spring frost (<32 'F) occurred on May 6, 10 days later than the 20-year mean date of April 26; the first fall frost occurred on September 23, 11 days earlier than normal (Table 9).

The weather in 1996 did not exceed any record weather events recorded over the
54-year history for the Malheur Experiment Station (Table 10).