SUBJECT: It was the hottest of Junes; it was the coldest of Junes. June 1999 St. Cloud weather summary An extremely schizophrenic June hit St. Cloud in the past month. There were periods of extremely hot and humid conditions and periods of incredibly cool weather. There were two major streaks of hot and sticky weather: during June 4-9 and June 21-26. During these 12 days, the average temperature was 74.8 degrees (avg high 86.3, avg low 63.3) with no high temperature cooler than 81 degrees. This period also included the first two 90-degree highs of the year (25th and 26th), which were the highest June temperatures recorded since 1997. Then, there were the cold periods. During June 13-20 and June 27-30, the average temperature was 59.4 degrees (avg high 69.4, avg low 49.5), which is typical of mid-May or mid-September. June had 8 days with a low temperature in either the 40's or 30's, the most since the chilly June of 1992. Finally, there was the arctic tundra of June 1 which had a high of only 47 degrees, tying the coldest ever high for the day with June 1, 1945 and tying the second coldest high in June history. The coldest high ever recorded in June was 45 degrees on June 4, 1935. Of course, the warm extremes and the cold extremes cancelled each other out, leaving the average temperature about a degree warmer than normal. What was the cause of the extremes? During the warmer periods, the jet stream was blowing from the central or southern Rockies right over or just to the north of Minnesota. This has put St. Cloud near the boundary between cooler air to the north and hot, sticky air to the south. The showers and thunderstorms which rumbled along this boundary kept the humidity, and therefore, the overnight temperatures, high. These thunderstorms also accounted for the 4.00 inches of rainfall during the month. Still, this was 0.6 inches below normal. Because the rain was produced by thunderstorms, rainfall did vary. The St. Cloud State University rain gauge received 5.08 inches of rain this month, which would have been above normal. During the cooler periods, we had an abrupt reversal of the jet stream, turning to blow out from Canada into the Southeastern U.S., allowing cooler drier air to move over us. The start of July has marked a return to the warm, sticky pattern. We'll see how long it lasts. JUNE STATISTICS JUNE 1999 NORMAL TEMPERATURE ( F) Average high temp 76.3 77.4 Average low temp 55.2 52.2 Average temp 65.7 64.8 Hottest high temp for the month 91 on the 25th Coolest high temp for the month 47 on the 1st (tied record; see below) Warmest low temp for the month 69 on the 22nd Coolest low temp for the month 39 on the 17th Records: Daily cold high: 47 on the 1st (tied record set in 1945) PRECIPITATION (IN) JUNE 1999 NORMAL Total for month 4.00 4.60 Maximum daily amount .91 on the 5th ============================================================================= Bob Weisman, Meteorology Professor SUPERVISOR: Shirley (age 7) Earth Sciences Department PHONE: (320) 255-3247 (V) MS 48 (800) 627-3529 (TTY via Saint Cloud State University Minnesota Relay Service) 720 4th Avenue South FAX: (320) 255-4262 Saint Cloud, Minnesota 56301-4498 EMAIL: scsweisman@tigger. stcloudstate.edu ===============================================================================
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