Cold start to AprilMany observers reported very cold temperatures for the first few days of April. In the central and northern counties overnight lows dipped into the single digits F. Embarrass, Kabetogama, Orr, International Falls, Tower, and Crane Lake reported overnight lows below 0 degrees F, with a -6 degrees F at Crane Lake on April 3rd. During the daytime hours on Wednesday (April 3)the winds shifted from the north to the south raising the temperature at Canby from a morning low of 25 degrees F to an afternoon high of 63 degrees F under sunny skies. Similarly Madison, MN (Lac Qui Parle County) rose from a morning low of 23 degrees F to an afternoon high of 61 degrees F.
Red River Valley flood risk pushed back on the calendarWith the cool start to April and expected cooler than normal temperatures into next week, the NWS-Grand Forks office issued an updated hydrological outlook this week for the Red River of the North which projected the flood risk on that watershed not to materialize until after April 16th. Further the northern end of the Red River Valley may not see flood volume flow until the last week of the month. The actual flow volume on this watershed will be highly dependent on how fast the thaw of the snow pack occurs and how much precipitation falls during the second half of the month. For those interested in following the day to day volume flow along the main stem of the Red River and its tributaries you can see the hydrographs for gage points on these watersheds at the "Puddles" section of our web site.
Weekly Weather potpourriHeavy rains brought flooding to many parts of Argentina this week. Up to 16 inches of rainfall occurred near La Plata and Buenos Aires reported some of its worst flooding in a century. Thousands of people were displaced from their homes, and many more were without power. At least 31 deaths were blamed on the storms and flooding.
The United Kingdom Meteorological Office announced this week that their WOW program (Weather Observations Website) has now received over 100 million weather reports from enthusiasts all over the world since its beginnings in 2011. The site shares measurement data, comments, and photos about the weather from all parts of the world. You can view this web site here.
The latest national drought assessment from Brad Rippey of the USDA:
-Overall U.S. drought coverage increased slightly (0.28%) to 51.92% of the contiguous U.S. Despite the slight weekly increase, drought coverage is down 9.17% since the beginning of 2013 and down 13.53% from the record-high of 65.45% on September 25, 2012.
- The portion of the contiguous U.S. in the worst category – D4, or exceptional drought – increased one-tenth of a percentage point 5.20%. D4 coverage has ranged from 5 to 7% for 34 consecutive weeks (August 14, 2012 – April 2, 2013).
- Once again, there were no changes in hay in drought (51%), cattle in drought (62%), and winter wheat in drought (56%). Those numbers have remained unchanged since March 12.
Ohio State University researchers have retrieved ice cores from the Peruvian Andes that provide a high resolution of year to year climate for nearly 1800 years. In this record they can see from the signature of chemical composition within the ice layers an indication of El Nino activity in the equatorial Pacific Ocean, providing the longest known record of El Nino. These ice cores are being preserved to study other indicators of ancient climate fluctuations as well. You can read more about this here.
MPR listener questionHow deep is the frost right now and will much of the rain in the next couple of days soak into the ground?
Answer: With the loss of snow cover the soil is beginning to thaw from the surface downward more rapidly. In southern Minnesota and the Twin Cities area the top 5 to 8 inches of soil has thawed out, however there is still a frost layer between 8 and 20 inches in most places. Further west and north in the Red River Valley frost still extends down to 30-40 inches deep and there is relatively little surface thawing so far. The rainy pattern we expect to see develop for the weekend and extend into next week will help accelerate the thaw, and indeed some of the rainfall will go into the dry soil (at least in southern MN), but not too much depth. In the north the additional precipitation will likely add to the snow pack before it melts later this month.
Twin Cities Almanac for April 5thThe average MSP high temperature for this date is 45 degrees F (plus or minus 12 degrees F standard deviation), while the average low is 28 degrees F (plus or minus 10 degrees F standard deviation).
MSP Local Records for April 5thMSP weather records for this date include: highest daily maximum temperature of 80 degrees F in 1991; lowest daily maximum temperature of 29 degrees F in 1982; lowest daily minimum temperature of 12 F in 1979; highest daily minimum temperature of 60 F in 1921; and record precipitation of 0.91 inches in 1999; Record snowfall is 1.5 inches in 1964.
Average dew point for April 5th is 27 degrees F, with a maximum of 60 degrees F in 1929 and a minimum of -2 degrees F in 1979.
All-time state records for April 5thThe state record high temperature for this date is 88 degrees F at Madison (Lac Qui Parle County) in 1991. The state record low temperature for this date is -18 degrees F at Warroad (Roseau County) in 1936. State record precipitation for this date is 2.95 inches at Pigeon River Bridge (Cook County) in 1933; and the state record snowfall for this date is 28.0 inches also at Pigeon River Bridge (Cook County) in 1936.
Past Weather Features:Between 5:30 pm and 7:00 pm on April 5, 1929 an F-4 tornado (winds 207-260 mph) crossed portions of Hennepin, Anoka, Ramsey, Washington, and Chisago Counties and into western Wisconsin with an estimated path length of nearly 80 miles. It injured 40 people and killed two farm residents near Forest Lake. Many farm homes and farm buildings were destroyed by this storm.
The first week of April in 1979 continued a winter-long cold and snowy weather pattern in the Red River Valley. Several nights brought temperatures that were below 0 degrees F and measurable snowfalls occurred on the 4th and 5th. Many observers still reported over a foot of snow on the ground. Heavy rains combined with warm temperatures brought spring snow melt flooding to the Red River Valley during the third week of the month.
April 5-7, 1991 brought mid-summer heat to Minnesota, with over 40 communities reporting daytime high temperatures of 80 degrees F or higher. Temperatures even reached the low 90s F in some western counties and farmers were out planting small grain crops.
April 5-6, 1997 brought a late season blizzard to the Red River Valley, depositing 4-7 inches of fresh snowfall on top of an already snow laden landscape. Many communities along the Red River of the North were already sandbagging in the middle of a spring flood fight. The blizzard conditions brought heavy, wet snow, along with winds up to 65 mph, and dangerous windchill conditions. The snow melt flood that followed was the worst of the 20th Century for many points along the Red River watershed.