Best days of the summer this weekWeatherwise, we are experiencing perhaps one of the best starts to July in recent years. Low temperatures have been in the 50s and 60s F with daytime highs in the upper 70s to low 80s F and plenty of sunshine. Little rainfall so far this month following a generally wet June and wet spring. Thankfully dewpoints have remained in the comfortable 50s F providing near perfect weather for outdoor activities. Even at Embarrass, MN overnight lows have not dropped below 41 degrees F, while daytime highs have risen to 82 degrees F.
The July 4th weekend will bring some warmer than normal temperatures that will linger through Monday. On July 4th MSP, Wheaton, Fergus Falls, Browns Valley, Montevideo, Milan, Wheaton, Moorhead, and Ortonville all reached 90 degrees F. This marked the 22nd time the Twin Cities has recorded at least 90 degrees F on Independence Day since 1871.
New ice-in data set for Minnesota lakesThe DNR-State Climatology Office has developed a web-based climatology for ice-in dates on Minnesota lakes to match the popular and widely utilized ice-out data set that has been in play for years. The period of record varies by lake but users can look at average dates in the fall when lakes freeze up, as well as what the historical extreme dates (early and late) have been. For access and further information you can go to the web site.
Global Upper Air StationsUnder the jurisdiction of the World Meteorological Organization (WMO) and the Global Observing Systems Information Center (GCOS) a worldwide network of upper air observations provides government weather services and the atmospheric and climate science research communities with profile measurements (temp, dewpoint, pressure, wind speed and direction) of the Earth's atmosphere. Many of these measurements are done on a 12 hourly basis to initialize numerical forecast models. The instrumented balloons, called radiosondes, are launched from a variety of land-based and ship-based stations. The Twin Cities radiosonde data are depicted graphically at the following web site.
The WMO has a list of over 1700 such stations worldwide, with most of them located in the countries of the northern hemisphere. There is great disparity in data coverage, with North America and Europe having a relatively large number of radiosondes launched each day, and Africa having very few. There is a good article on the NOAA web site this week highlighting the value of these measurement systems, both in weather forecasting and in atmospheric research. You can find it here.
Weekly Weather potpourriWeatherwise magazine features an article by Sean Potter about July, 1776 in Philadelphia, PA where Thomas Jefferson was taking part in deliberations that eventually produced the Declaration of Independence. During that month he kept daily weather records and observers. It was somewhat hot and humid outside and even more stifling in the chamber where the 2nd Continental Congress was meeting. You can read more about this article here.
Hurricane Dalila was churning in the Eastern Pacific Ocean southwest of Puerto Vallarta, Mexico this week. It was expected to slowly dissipate out to sea and not be a threat to Mexico. Maximum winds were ranging from 85 to 95 mph producing sea wave heights of 30-35 feet. Tropical Storm Erick was spinning off the west coast of Mexico further south. It was expected to strengthen over the weekend.
For southeastern Minnesota crop producers many acres remain unplanted due to the wet spring conditions. Weeds are prolific and large in these fields and pose a long term concern due to the amount of their seed production. According to Dr. Jeff Gunsolus, weed specialist with Extension control of these weeds by mowing or tillage would be a good strategy to deploy at this time. You can read more on this topic in the Crop Newsletter.
Well-known Japanese water scientist Masaru Emoto will be in the Twin Cities to give two programs this month on the unique properties of water relative to wave and sound. You can read more about him and these events at the following web site:
MPR listener questionHaving started July so sunny and dry here in the Twin Cities we were wondering what the monthly rainfall extremes are for the month? Also what is the historical range in the number of rainy days during the month?
Answer: For the Twin Cities climate record, 1871-2012, the driest July was in 1894 when only 0.20 inches of rain fell. The wettest was in 1987 when 17.90 inches fell (10 inches fell on July 23rd in six hours that year). The fewest days with rain occurred in 1895 with just 3 days, while the most rainy days were recorded in 1972 and 1987 with 16 days.
Twin Cities Almanac for July 5thThe average MSP high temperature for this date is 83 degrees F (plus or minus 7 degrees F standard deviation), while the average low is 62 degrees F (plus or minus 6 degrees F standard deviation).
MSP Local Records for July 5thMSP weather records for this date include: highest daily maximum temperature of 100 degrees F in 1982; lowest daily maximum temperature of 66 degrees F in 1905; lowest daily minimum temperature of 45 F in 1967 and 1972; highest daily minimum temperature of 78 F in 1982; and record precipitation of 1.62 inches in 1994; No snow has been recorded on this date.
Average dew point for July 5th is 59 degrees F, with a maximum of 77 degrees F in 1949 and a minimum of 40 degrees F in 1972.
All-time state records for July 5thThe state record high temperature for this date is 108 degrees F at Pipestone (Pipestone County) in 1936. The state record low temperature for this date is 27 degrees F at Tower and Embarrass (St Louis County) in 2001. State record precipitation for this date is 6.25 inches at Albert Lea (Freeborn County) in 1943; and no snow has fallen on this date.
Past Weather Features:Baseball size hailstones fell overnight on July 5, 1966 at Detroit Lakes (Becker), MN. These were some of the largest hailstones every observed in the area, one was nearly a foot in circumference. Strong winds up to 48 mph damaged some buildings in the area and thunderstorms brought nearly 2 inches of rain.
July 5-6, 1978 brought heavy thunderstorms to southeast Minnesota from Dodge to Winona Counties. The heaviest band of 6-7" occurred just south and east of the Rochester area. The Zumbro River and it's tributaries (Bear Creek, Silver Creek, Cascade Creek) went into flood through Rochester causing extensive damage. The July 6 crest at the Rochester river gage established an all-time record of 23.36 ft and 30,500 cfs. This flood and yet another in September prompted the construction of a major flood control project by the U.S. Army Corps of Engineers and the Natural Resources Conservation Service in and around Rochester. The project was completed in 1995, at a cost amounting to $92 million and protects the city against a 200-year recurrence interval flood event.
July 5, 1988 was arguably the warmest in state history with nearly every observer in the state reporting a daytime high in the 90s F. Even International Falls reached a high of 96 degrees that day. Over 20 communities reported afternoon temperatures of 100 degrees F or higher.
July 4-5, 1999 brought a destructive "derecho" to northern counties, especially across the BWCA where millions of trees were blown down by 70-90 mph straight-line winds. Heavy thunderstorms brought 4 to 8 inches of rainfall to parts of St Louis, Lake, and Cook Counties. Some roads were closed for a time due to flooding and washouts. The Hibbing Airport reported 7.81 inches of rainfall, a record amount there.
July 5, 2001 brought a rare July frost to northern Minnesota communities. Hibbing, Embarrass, Tower, Brimson, and Kelliher, reported morning low temperatures that ranged from 27 to 32 degrees F. After starting the day at 28 degrees F Kelliher warmed all the way up to 73 degrees F by mid-afternoon.