2014年7月 Saint 云 天气 Summary

Drying Out 与 Actual Average 温度

St. 2014年7月云天气摘要

Drier July Allows Rivers and Lakes to Recede

For the first time since February, rainfall slowed down dramatically in St. 云. According to the statistics from the St. 云 Regional Airport, the total rainfall in July was 1.25英寸，2英寸.06 inches less than the 1981-2010 average. 那还剩下St。. 云6.93 inches above average for the April 1-7月31日 growing season 到目前为止 (20.实际是07英寸，13英寸.平均10英寸). That ranks as the 7th highest April-July rainfall in St. 云记录. 自今年年初以来，圣. 云已经找到了23.78英寸，还是7英寸.99 inches above average and the 5th rainiest year to date. The last time there was so much rain early in the year was in 1990. The most rainfall through the first 7 months of the year (31.78 inches) and for the April-July period (23.10英寸)是1897年.

There were only 8 days 与 measurable rainfall in July. While that's only one day less than the average (9.3 days), it's the fewest days 与 measurable precipitation since February. St. 云 did miss on some heavy rains in northern Minnesota during a couple of periods. There was some heavy rainfall in northwestern Minnesota (2-4 inches) on July 10 and another bout of heavy rainfall in northern Minnesota on 7月21日-22. 但是，圣. 云 was consistent 与 smaller rain amounts in most of the southern half of Minnesota. 在没有超过 连续三天没有雨 从4月11日到7月14日. 云 had 10 straight dry days between July 15 and July 24 and only one day 与 measurable rainfall in the last 17 days. 这 allowed much of Minnesota to catch up on good outdoor days.

这 finally allowed the very high water levels in many Minnesota lakes to drop a bit. Much of the southern half of Minnesota saw lake levels drop enough to see many wake restrictions eased and 看水流 drop back to normal (green) flow in much of the southern two-thirds of Minnesota 与 still some pockets of the top 25% in the Mississippi Basin between Brainerd and Minneapolis and in the Lower Minnesota River Basin from Redwood Falls to the Twin Cities. Note that most of central Minnesota was 在最高的10%的水流中 在六月底. Riverflow is still very high around the Red Lakes, 卡斯湖, 湖Winnibegoshish, 以及底特律湖区.

不像你想的那么酷

Temperature-wise, July continued the impression of this "cool summer.“这主要是由于 7月14-17日爆发感冒. St. 云确实设置了一个 创纪录的最高气温65华氏度 on the 14th and had three lows 与in a degree of 50. However, the 14th was the only day 与 a low cooler than 60 degrees (七月平均值) and there was only one low cooler than 50 degrees (less than the 七月平均2.1天). 如果算上六月，圣. 云 has fewer than average of these cool temperatures and is not near a record.

The atmosphere finally addressed the lack of 90 degree highs through mid-July. Highs of 90 on the 20th and 94 on the 21st 带来了七月的数字 90度高点 to 2. 这 was the latest 90-degree high since 1993, when the first one was set on 8月10日. We still are far below the average number of 90 degree days (通常11.4天的暑假). Both 2008 (3 days) and 2009 (2 days) had similar numbers of 90-degree days.

Overall, the July temperature ended up being 70.2度，差不多是平均值. 81年.7 degree average high was just short of a degree away from the average July high (82.3 degrees), so we have caught up substantially during the last half of July. The drier weather also allowed near average low temperature (58.7度). Warm lows from humid air was mainly responsible for the 比六月平均温度高. 这 七月是自2009年以来最酷的七月 and the second coolest of the past 10 years, so we have usually seen warmer Julys recently.

请注意St. 云 still had a 72 degree low on 7月21日, the second low of at least 70 degrees this summer 到目前为止. These warm lows are far more rare (3 per summer) than 90 degree highs (11.每温暖季节4个).

The dry out came because the hot high in the western third of the US grew larger and pushed further to the north. 这, 起初, pushed the cool Canadian air mass into the eastern two-thirds of the country during the middle of the month. After that, the cold lows parked themselves over Quebec and Ontario, so the eastern third of the country stayed cool and wet, but the Northern Plains had mostly near average temperatures on the back side of the cool air. 这 Canadian air was dry enough to make it hard for any warm fronts to squeeze a lot of moisture out of any weather systems. 春天和夏天的时候, the Northern Plains were mostly right on the boundary between the hot, 潮湿的空气和稍冷的空气, 但空气不那么干燥, so 雷雨频繁.

    2014年7月统计数据