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Extension > Mark Seeley's WeatherTalk > September 2013

Friday, September 27, 2013

Preliminary Climate Summary for September

Preliminary Climate Summary for September

Average September temperatures reported by observers around the state ranged from 2 to 5 degrees F above normal. Several days early in the month hit 90 degrees F or higher, with high dewpoints (70 F) pushing the Heat Index Values between 98 F and 102 F on September 9th. The highest temperature for the month was 97 degrees F at Preston on the 7th, while the lowest was 26 degrees F at Embarrass on the 17th and at Brimson on the 22nd. Numerous frosts occurred in northeastern and north-central counties, while the rest of the state escaped a September frost, which was good for crop maturation and drying. Corn harvesting had begun in some areas of the state.

Precipitation for September was below normal for most observers, especially the northwestern and southern counties which reported just 5 or less days with rainfall. Most observers reported between 1 and 2 inches. Some of the driest spots in the state were Argyle (Marshall County) with just 0.11 inches (their driest September ever surpassing 0.16 inches in 1948), Roseau with 0.18 inches (2nd driest September to 0.07 inches in 2012), Blue Earth (Faribault County) with 0.58 inches (2nd driest September to 0.55 inches in 2000), Winnebago (Blue Earth County) with 0.76 inches (4th driest September), and Austin with 0.82 inches (9th driest September). Thanks to some widely scattered but intense thunderstorms a few spots reported above normal rainfall for the month including 4.44 inches at Grand Portage, 4.04 inches at Kabetogama, 5.03 inches at Ottertail, 5.65 inches at Fergus Falls, 4.67 inches at Pelican Rapids, 5.14 inches at Long Prairie, and 4.49 inches at Big Lake. Thunderstorms brought large hail and strong winds (50-75 mph) to parts of central Minnesota on the 19th.

With September being the 3rd consecutive drier than normal month for the state, many more counties returned to the drought status of earlier in the year, with over half the state landscape designated to be in moderate to severe drought by month's end.

September 1807 in Minnesota

Alexander Henry was an explorer and trapper for the old Northwest Fur Trade Company at the beginning of the 19th Century. He explored and lived in the Red River Valley of Minnesota and North Dakota from 1800 to 1808, establishing camps and building temporary forts in many places along the river, including near Pembina and Drayton, ND as well as Warren, Oslo, and Red Lake Falls, MN. Thanks to his daily weather journal, one of the oldest in our region, we have a daily written record of the weather in northwestern Minnesota for the period from September 1807 to June 1808.. September, 1807 according to Henry was highly variable. Very sunny and warm early in the month with several days in the 80s F. Then it turned cool and showery by mid-month with a number of frosts and a hard freeze on the 16th (28 F). Fall coloration and leaf drop came about mid-month, and he observed the migration of geese and swans heading south. September 18th brought every kind of weather according to Henry's journal...."strong winds, heavy rain, hail, and even two inches of snow!" This was followed by another hard freeze on the 20th (27 F). The month concluded with yet another freeze on the 28th, followed by light showers and foggy weather through the end of the month.

Henry's journal is a treasure to a historian or climatologist as it is one of the few written records of the daily weather from such an early time period, before settlement of the Red River Valley. He documents a number of spring snow melt floods in the region and remarks about how the floods used to drown hundreds of buffalo which would graze the numerous islands. The 1800-1808 period is still encompassed by the northern hemisphere's Little Ice Age that extended to roughly 1850. In this context it is not unexpected to find that Alexander Henry recorded snows in September and winter snow cover persisting well into the month of May in northern Minnesota.

Coming up, October a favorite month for many

I came across this commentary about October's weather in an 1895 edition of the Minneapolis Journal...."October is generally a kingly month in Minnesota. It opens with the usual affluence of sunshine and quickening, bracing air, which [is} stimulating to the senses. Day after day, the transformation of summer greenery into the royal and gorgeous tones of autumn will go on and summer's silent fingering will be overwoven with pageantry of color which no human art can call into being. The recessional of the year is grander than the processional...."

From numerous conversations with weather observers and other friends, I have drawn the conclusion that many of us cherish October as a favorite month. Some of the memories shared include:
A pageantry of landscape color for outdoor weddings, harvest festivals, Oktoberfest dinners...visits to the apple house and glasses of fresh cider..picking out pumpkins...song-filled hay rides...filling the pantry with the garden harvest including homemade pickles and apple sauce...frosty morning bike rides under clear, blue skies...wearing handmade sweaters and embroidered sweatshirts...a bonfire rally...the last boat trip...migrating bird formations...drying and arranging the last of the cut flowers...football and soccer games...and of course MPR's fall pledge drive (which starts October 10).

Climate Change Adaptation Conference at the Science Museum on November 7, 2013

Several organizations are partnering to host the first statewide conference on Climate Change Adaptation, Planning and Practice. It will take place at the Science Museum of Minnesota in downtown St Paul on November 7, 2013. Registration for the all day program is only $50. Sessions will be devoted to city planning, agriculture, transportation, natural resources (including watershed management), and public health.

Weekly Weather potpourri

The highly anticipated AR5 report from the IPCC was partly released on Friday (September 27th), the remainder of the report will be released on Monday (Sept 30). IPCC scientists emphasized that confidence about the human fingerprint on climate change has grown to 95 percent. Specific environmental features that are clearly related to human activity include increasing frequency of severe thunderstorms and heat waves, as well as continued loss of Arctic sea ice and sea level rise. The summary for policymakers and the final AR5 report will be available for reading here.

Researchers from the University of Missouri this week published a study of the fossil evidence recovered from Tanzania representing the Late Cretaceous Period (90 million years ago) and determined that when the Earth's atmosphere contained up to 1000 ppm of carbon dioxide there were no continental ice sheets present. You can read more about this study here.

Another study from Stanford researchers and published in the Proceedings of the National Academy of Science suggests that continued climate change will lead to a higher frequency of severe thunderstorms across the USA. Models of the future changes in climate show an increase in convective available potential energy (CAPE), a measure of energy correlated with the development of severe thunderstorms. You can read more about this study here.

Portions of Vietnam, Thailand, and Laos, already plagued by flooding and heavy rains this month are expected to see even heavier rainfall from Tropical Storm Wutip in the Western Pacific Ocean. This storm is expected to make landfall late in the weekend and early next week bringing several inches of rain to the area.

NOAA National Weather Service expects the first significant autumn snowfall to occur in portions of WY, MT, and ID Friday and Saturday, with up to a foot of snow in the Wind River Range of western Wyoming. It will be short-lived as temperatures warm into the 40s and 50s F later in the weekend.

Some drought notes this week from Brad Rippey with the USDA World Agricultural Outlook Board:
-During the drought-monitoring period ending September 24, U.S. severe to exceptional drought (D2 to D4) coverage fell from 28.35 to 25.33%; extreme to exceptional drought (D3 to D4) coverage fell from 6.85 to 4.33%; and exceptional (D4) drought coverage fell from 0.43 to 0.31%. In all three cases (D2 to D4, D3 to D4, and D4), drought coverage stood at its lowest level since June 2012.
- For the week ending September 24, corn and soybeans in drought [across the USA] were down one percentage point, with 54 and 44% of the respective production areas categorized as being in moderate drought (D1) or worse. There were two percentage point decreases apiece in drought coverage for cattle (51% in drought) and hay (37%). Forty percent of the U.S. winter wheat production area was in drought on September 24, down three percentage points from a week ago.

MPR listener question

I haven't heard you talk about stored soil moisture values in a long time. With this recent sequence of dry months and return of drought how much moisture is stored in the soil this fall?

Answer: Good question, and of course the answer varies with geography. In southwestern Minnesota at Lamberton a measurement made last week showed just 1.49 inches of moisture available in the top 5 feet of soil. That's very dry (average for this time of year is about 4 inches) but not as low as last year at this time (0.72 inches). At Waseca, in south-central Minnesota, a recent measurement shows over 7 inches of stored moisture remaining in the top 5 feet of the soil profile (slightly above normal for this time of year), and well above last year when only about 2 inches was stored. Elsewhere estimate ranging from 2 to 4 inches are pretty common.

Twin Cities Almanac for September 27th

The average MSP high temperature for this date is 66 degrees F (plus or minus 11 degrees F standard deviation), while the average low is 46 degrees F (plus or minus 8 degrees F standard deviation).

MSP Local Records for September 27th

MSP weather records for this date include: highest daily maximum temperature of 88 degrees F in 1987; lowest daily maximum temperature of 40 degrees F in 1942; lowest daily minimum temperature is 29 degrees F in 1942 and 1991; highest daily minimum temperature of 64 F in 1891; and record precipitation of 0.54 inches in 1947; and no snow has fallen on this date.

Average dew point for September 27th is 45 degrees F, with a maximum of 67 degrees F in 1905 and a minimum of 24 degrees F in 1951.

All-time state records for September 27th

The state record high temperature for this date is 97 degrees F at Beardsley (Big Stone County) in 1894, at Hallock (Kittson County) and Wheaton (Traverse County) in 1952, and at Canby (Yellow Medicine County) in 1956. The state record low temperature for this date is 13 degrees F at Beardsley (Big Stone County) in 1893. State record precipitation for this date is 3.50 inches at Wolf Ridge Environmental Learning Center (Lake County) in 1996; and state record snowfall for this date is 6.0 inches at Benson (Swift County) in 1942.

Past Weather Features:

September 27-28, 1894 brought a fall Heat Wave to many parts of Minnesota with low to mid 90s F. A strong cold front caused temperatures to plummet into the 30s by the evening of the 29th.

September 26-27, 1942 brought an early season snow storm to Minnesota. A heavy wet storm made travel difficult in rural areas. Bird Island reported 8 inches, Long Prairie 7.5 inches, Detroit Lakes, Benson and Willmar reported 6 inches, New Ulm 5.5 inches, and Grand Meadow 5 inches. The snow was short-lived as temperatures warmed into the 50s and 60s F by the end of the month.

Thunderstorms brought heavy rain to northern Minnesota communities on September 27, 1996. Lutsen Mountain received nearly two inches of rain and many other areas reported well over an inch. Wolf Ridge Environmental Learning Center near Finland on the North Shore reported an all-time September rainfall record of 3.50 inches.

Outlook

 Mostly cloudy and showery on Saturday with somewhat cooler temperatures and strong winds. Dry and sunny on Sunday and Monday with warmer temperatures. Generally dry and warm next week with a chance for showers and thunderstorms by late Thursday and Friday.

Friday, September 20, 2013

NOAA-Climate Prediction Center seasonal climate outlook

The NOAA-Climate Prediction Center released the new seasonal climate outlook on Thursday (Sept 19) this week

The new climate outlooks released by NOAA-CPC on Thursday (Sept 19) favor a warmer than normal October across all of the Great Lakes Region, including Minnesota. Then the balance of the autumn and early winter shows equal chances for warm or colder than normal conditions to prevail. Though the precipitation outlook does not favor below normal values of precipitation during the balance of autumn the CPC drought outlook shows that many parts of Minnesota are expected to remain in drought through the month of December. You can see the various climate outlooks at the CPC web site.

 Cool up north

Since last Saturday (September 4) many northern observers have reported multiple frosts and the lowest temperatures since the middle of last May. Some lows reported this week included:
31 degrees F at Grand Rapids and Little Fork
30 degrees F at Roseau, Leech Lake, Kabetogama, and Wright
29 degrees F at International Falls, Ely, and Floodwood
28 degrees F at Brimson, Hibbing, and Tower
27 degrees F at Isabella, Orr, and Crane Lake
26 degrees F at Embarrass

Further north at Thompson, Manitoba they reported a new record low temperature on September 15th of 21 degrees F. The cool temperatures in the north helped accelerate fall leaf color change with is reported to be about 25 percent in play now and will perhaps reach peak in some areas up north next week.

Drought Update

Spotty, but significant thunderstorms visited the state over September 15-16 (Sun-Mon) this week bringing 1-2 inches of rain to some areas. Among those reporting new daily record amounts of rainfall for September 15th were Ottertail with 1.92 inches, Rothsay with 1.52 inches, Milaca with 1.25 inches, and Mora with 1.12 inches. Though not record-setting other significant 2-day rainfall totals included 1.85 inches at Moorhead and 2.23 inches at Pelican Rapids. As a result of these rains the Minnesota landscape designated to be in drought shrunk by 4 percent from 55 percent last week to 51 percent his week. Another round of thunderstorm rains on Thursday (Sept 19) brought significant rainfall to parts of western and southern Minnesota with 1-2 inch amounts common and wind gusts ranging from 40 to 60 mph (77 mph in Renville County) which flattened some corn fields. Among those observers reporting over an inch of rainfall were Madison, Marshall, Princeton, Hutchinson, Montevideo, Rush City, La Crescent, and Bird Island. At Big Lake in Sherburne County a rainfall total over 3 inches was reported.

Elsewhere in the USA the largest drought improvement from last week to this occurred in the state of Colorado, where September 9-15 brought 10-21 inch rains to many parts of the front range. Many cities reported flooded roads, basements, and significant damage to infrastructure. A number of towns were isolated by flood waters. Among these cities were Aurora (15 inches), Boulder (up to 21 inches), Golden (nearly 12 inches), and Loveland (11 inches). Because of the rains the area of the Colorado landscape in severe to extreme drought shrunk from 58 percent to 17 percent this week. The official Coop observer at Boulder, CO reported the wettest month in history (17.08 inches) and wettest year in history (30.14 inches) shattering all records back to 1893.

Climate Change Adaptation Conference at the Science Museum on November 7, 2013

Several organizations are partnering to host the first statewide conference on Climate Change Adaptation, Planning and Practice. It will take place at the Science Museum of Minnesota in downtown St Paul on November 7, 2013. Registration for the all day program is only $50. Sessions will be devoted to city planning, agriculture, transportation, natural resources (including watershed management), and public health.

Weekly Weather potpourri

In the Western Pacific Ocean Super Typhoon Usagi was taking aim at Taiwan and Hong Kong for the coming weekend. As of Friday wind speeds ranged up to 175 mph and sea wave heights were approaching 50 feet with this storm. This moderately large and extremely strong storm will bring heavy rains to Taiwan and Hong Kong over the next 72 hours. Both storm surge and wind damage is expected when the system makes landfall.

Tropical Storms Manuel and Ingrid pounded Mexico with heavy rains earlier this week causing the death of at least 47 people and flooding many areas. More rains are expected due to the development of another Tropical Storm in the Gulf of Mexico over the weekend and into early next week.

Dmitry Kiktev, Deputy Director of the Russian weather agency is predicting near normal temperatures and generally favorable conditions for the Winter Olympic Games to be held in Sochi over February 6-23, 2013. As a precaution, organizers have stored nearly half a million cubic meters of snow in huge refrigerated reservoirs for deployment across the ski slopes should Mother Nature not provide an adequate amount of snow by the start of the Olympic Games. You can read more here.

 

MPR listener question

Earlier this year I heard you and Cathy talk about southeastern Minnesota (Grand Meadow specifically) as one of the wettest spots in the state. What are currently the wettest and driest spots in the state for 2013?

Answer: Fillmore County is probably still the wettest county in the state for 2013 as Ostrander reports over 40 inches of precipitation this year. Nearby Grand Meadow and Harmony have reported over 37 inches of precipitation for the year. The northwest is among the driest areas of the state. Both Warroad and Roseau report less than 15 inches for the year so far.

Twin Cities Almanac for September 20th

The average MSP high temperature for this date is 69 degrees F (plus or minus 10 degrees F standard deviation), while the average low is 50 degrees F (plus or minus 9 degrees F standard deviation).

MSP Local Records for September 20th

MSP weather records for this date include: highest daily maximum temperature of 94 degrees F in 1937; lowest daily maximum temperature of 47 degrees F in 1875; lowest daily minimum temperature is 28 degrees F in 1962; highest daily minimum temperature of 75 F in 1895; and record precipitation of 1.82 inches in 1902; A trace of snow fell in 1927 on this date.

Average dew point for September 20th is 48 degrees F, with a maximum of 72 degrees F in 1970 and a minimum of 22 degrees F in 1930.

All-time state records for September 20th

The state record high temperature for this date is 99 degrees F at Fairmont (Martin County) in 1891 and at Montevideo (Chippewa County) in 1984. The state record low temperature for this date is 14 degrees F at Karlstad (Kittson County) in 1973. State record precipitation for this date is 4.97 inches at Harmony (Fillmore County) in 1983; and state record snowfall for this date is 0.4 inches at International Falls (Koochiching County) in 1945 and again at Thief River Falls (Pennington County) in 1954.

Past Weather Features:

An 8-day Heat Wave prevailed over September 16-23, 1891. At least 13 Minnesota communities reported consecutive days with highs in the 90s F, and Montevideo topped out at 101 degrees F before cooling off to a high of only 68 degrees F on the 24th. September of 1891 proved to be the 4th warmest in state history.

A widespread hard-freeze ended the growing season for most parts of Minnesota on September 20, 1962. Many observers reported morning lows in the teens and twenties F. It was 28 degrees F as far south as Preston and Waseca. Indian summer came in October that year with a run of days with afternoon highs in the 70s and 80s F.

Another season ending hard frost and freeze came on September 20, 1973 with many observers reporting lows in the teens and twenties. Indian summer brought many days in the 70s F during October.

September 20, 1983 was extremely wet in southeastern Minnesota as strong thunderstorms brought 2-3 inches of rain to most places. Preston and Harmony were hit with nearly 5 inches of rain which caused a great deal of street flooding in those communities.

September 19-20, 1984 brought a brief September Heat Wave to the state with temperatures showing into the 90s F in 50 communities. Following the short Heat Wave temperatures plummeted on September 26th bringing a hard freeze to most areas.

A brief, small tornado (EF-0 winds 65-85 mph) touched down near Woodbury (Washington County) about 6:30 pm on September 20, 2007. No damage was reported as the funnel was on the ground for less than half a mile. Heavy rains and lightning strikes were reported from surrounding counties.

Outlook

Mostly dry over the weekend with near average temperatures. Increasing cloudiness and stronger winds on Sunday. Warming temperatures next week with a chance for showers late Monday into Wednesday. The month should end very warm by next weekend as well.

Friday, September 13, 2013

Continued warm and dry pattern

Continued warm and dry pattern

Despite the recent cool down temperatures so far this month are averaging from 3 to 6 degrees warmer than normal in most places. A brief respite occurred on Thursday and Friday this week (Sept 12-13) as a cool, dry Canadian air mass brought many overnight lows in the 30s F with much lower dewpoints. Perhaps we have seen the last of the 90 F temperatures, though it looks like next week daytime highs in the 80s F could return briefly with higher dewpoints and chances for thunderstorms.

Most of the state has seen drier than normal weather continue to prevail this month, especially in southern counties where rainfall totals are mostly less than a quarter of an inch. A few scattered spots in the north report above normal rainfall thanks to heavy, but widely scattered thunderstorms, including 3.64 inches at Fergus Falls, 3.08 inches at Long Prairie, 3.00 inches at Kabetogama, 2.83 inches at Ottertail, 2.32 inches at Grand Portage, and 2.30 inches at Brainerd.

The dry pattern has amplified and extended drought on the Minnesota landscape. Moderate or severe drought now extends over 55 percent of the state, and severe drought has been extended down along the bluff country in the Mississippi River Valley from Lake City to Winona. Some southern and central Minnesota communities have seen rainfall totals that are 6-7 inches below normal since July 15th. Further, according to the NOAA-Climate Prediction Center the extent of drought is expected to expand across southern parts of Minnesota over the remainder of September. You can always catch up on the latest assessment of drought each Thursday on our web site.

A salute to Coop observers Steve and Nancy Potter of Long Prairie, MN

The "Senior Perspective" a monthly news publication serving 35 counties in west-central Minnesota recently highlighted the activities and contributions of Steve and Nancy Potter, Cooperative weather observers for the National Weather Service near Long Prairie, MN (Todd County). Not only do they make daily weather observations on their farm, but they also contribute to the National Phenology Network, taking observations of lilacs, maples, and basswoods to assess seasonal variability as it might relate to climate change. Congratulations to Steve and Nancy on this recognition. The article can be found here.

Lyle Schaller retires

A long time colleague, Lyle Schaller of the National Weather Service in Chanhassen, MN retired this month after 51 years of federal service, most of which was with NOAA. He was a hydrometeorological technician responsible for measurement systems and data management, including instrumented balloon launches (radiosondes). He was especially generous with his time when I took groups of teachers through the National Weather Service and asked him to explain their operations. Lyle transferred from Sault St-Marie, MI to MSP National Weather Service Forecast Office in 1975, and later made the move to Chanhassen with the rest of the NWS staff. He has probably launched more weather balloons than anybody in the history of the National Weather Service. I am sure he will be missed and wish him all the best in his retirement. Thanks for your service Lyle.

Climate Change Adaptation Conference at the Science Museum on November 7, 2013

Several organizations are partnering to host the first statewide conference on Climate Change Adaptation, Planning and Practice. It will take place at the Science Museum of Minnesota in downtown St Paul on November 7, 2013. Registration for the all day program is only $50. Sessions will be devoted to city planning, agriculture, transportation, natural resources (including watershed management), and public health.

Weekly Weather potpourri

From Brad Rippey of the USD World Agricultural Outlook Board: Highlights for the drought-monitoring period ending 7 am EDT on September 10 include:
-Overall U.S. moderate to exceptional (D1 to D4) drought coverage increased (up 0.60 percentage point) to 50.69%. Exceptional drought (D4) was affecting 1.25% of the continental U.S., unchanged from week ago.
-Hot, mostly dry weather in the Corn Belt led to further increases in drought overage. Drought coverage in the nine-state Midwestern region increased from 8 to 32% during the 3-week period ending September 10. Drought currently covers 72% of Iowa, 55% of Minnesota, 43% of Wisconsin, 40% of Illinois, and 31% of Missouri.
- In the 3-week period ending September 10, corn in drought more than doubled from 25 to 55%. During the same period, soybeans in drought nearly tripled from 16 to 45%, hay in drought increased from 33 to 41%, and cattle in drought rose from 46 to 55%. With winter wheat planting underway (5% complete nationally by September 8), it’s useful to note that nearly half (45%) of the production area was in drought on September 10.

Humberto, the 8th named Tropical Storm of the Atlantic Hurricane Season became the first real hurricane of 2013 this week when its wind speeds increased to 85 mph. It remains far to the east of any islands or mainland areas. The NOAA NHC is also monitoring a low pressure area in the Gulf of Mexico which may become a tropical storm this weekend and bring heavy rains to Mexico. In the Western Pacific Ocean Tropical Storm Man-yi is expected to bring some heavy rain to portions of Japan early next week.

Thunderstorms late Wednesday night (Sept 11th) and early Thursday (Sept 12) brought heavy rains and flash flooding to parts of Colorado. The NWS had to issue numerous flash flood warnings as observers scattered from Fort Collins to Colorado Springs reported rainfall totals ranging from 4 inches to over 10 inches by Friday morning. Many creeks and rivers were overflowing and causing damages to roads and residences. The University of Colorado campus in Boulder was closed down. Scattered showers and thunderstorms were expected to prevail throughout the weekend as well.

Disparities in the climate change signals of Western Europe are documented in a paper published in Environmental Research Letters this week. Researchers from the London School of Economics and the University of Warwick analyzed temperature data sets from 1950 to the present and found regional differences in the rates of warming. The hottest part of the year, summer, has warmed the fastest in southern England, northern France, and Denmark. Conversely, there has been little warming detected in daytime summer temperatures in Norway and Sweden. The authors attempt to show regional differences in the temperature trends by season as well. You can read more here.

MPR listener question

How many hours was the dewpoint at 70 degrees F or higher this year in the Twin Cities? I have heard you talk about this and how it often leads the National Weather Service to issue a Heat Advisory.

Answer: So far, and this is likely to be close to the final number, MSP has reported 246 hours in 2013 with a dewpoint of 70 degrees F or higher. This is well above the historical average and over the past 68 years (since 1945) ranks as the 15th highest annual value (the highest being 512 hours in 2002). What is unusual about this year is that the majority of hours with such high dewpoints (including a record setting value of 77 degrees F on August 27th) occurred later in the year (late August and early September), and not in late June to early August as normally happens.

Twin Cities Almanac for September 13th


The average MSP high temperature for this date is 70 degrees F (plus or minus 9 degrees F standard deviation), while the average low is 53 degrees F (plus or minus 8 degrees F standard deviation).


MSP Local Records for September 13th

MSP weather records for this date include: highest daily maximum temperature of 95 degrees F in 1939; lowest daily maximum temperature of 51 degrees F in 1873; lowest daily minimum temperature is 33 degrees F in 1890; highest daily minimum temperature of 72 F in 1939; and record precipitation of 1.29 inches in 1921; No snow has been recorded on this date.

Average dew point for September 13th is 49 degrees F, with a maximum of 71 degrees F in 1939 and a minimum of 22 degrees F in 1923.


All-time state records for September 13th

The state record high temperature for this date is 100 degrees F at Redwood Falls (Redwood County) in 1939. The state record low temperature for this date is 17 degrees F at Roseau (Roseau County) in 1975. State record precipitation for this date is 4.10 inches at Theilman (Wabasha County) in 1978; and no snow has fallen on this date.

Past Weather Features:

Frost on September 13, 1923 brought an end to the growing season in many agricultural areas of the state. Many observers reported overnight lows in the 20s F, even in southern counties of the state. Red River Valley areas fell into the teens. Some crops were damaged by the early frost.

A 3-day Heat Wave prevailed from September 13-15, 1939, producing the some of the hottest mid-September temperatures in state history. The vast majority of observers reported record-setting highs in the 90s F, and at least 10 Minnesota cities reported daytime highs of 100 degrees F or greater. Even Two Harbors along the shores of Lake Superior reached a high of 94 degrees F.

September 14, 1964 is the earliest fall date when a measurable amount of snowfall was reported in the state. This happened at International Falls, though it was very short-lived as the daytime high rose to 59 degrees F the next day.

Thunderstorms brought record-setting rainfalls to many parts of the state over September 12-13, 1978. Rainfall totals ranged from 3 to 6 inches, with the heavier amounts in southeastern counties, where the Zumbro River went beyond flood stage. Many roads were flooded. It was the 8th and last major flash flood of the year 1978. Golf ball size hail fell in some areas and lightning started a large fire in Alexandria, MN.

Outlook

Near normal temperatures over the weekend with a chance for scattered showers, especially on Saturday night. Generally unsettled weather next week with frequent chances for showers (Tue-Thu) and a warming trend in temperatures by Wednesday. Cooler again by next weekend.

Friday, September 6, 2013

September starts cool and dry

September starts cool and dry

The first five days of September have started drier than normal (just as July and August did), while temperatures have been averaging 1 to 3 degrees F cooler than normal in most places. Many observers have already reported morning lows in the 30s including just 33 degrees F at Embarrass, and 34 degrees F at Bigfork, Crane Lake, and Chisholm. Temperatures as cold as 39 degrees F were reported as far south as Byron and Grand Meadow in southeastern Minnesota. Marshall, MN reported the state high of 92 degrees F on the 1st, while a few locations also reported some spotty rainfall on that date.

Rainfall deficits continue to mount in many parts of the state. The U.S. Drought Monitor now shows that over 53 percent of the state landscape is in moderate to severe drought. Severe drought is now designated for parts of Stearns, Sherburne, Benton, Wright, Meeker, and Kandiyohi Counties in central Minnesota. These counties and others had been drought-free since mid-May. Volume flow on many Minnesota watersheds is down as well, in some cases well below average for this time of year. Unfortunately the outlook favors warm and dry weather through the third week of September for most of the state.

DNR Fall Color Web Site

The DNR Fall Color web site is up and running with frequent updates on fall colors around the state. It is a good resource to plan trips for viewing the beautiful autumn foliage in our state. So far, even in the far northeast vegetation color change is less than ten percent, but more nighttime temperatures in the 30s F may accelerate this process. Visit their web site for updates on a daily basis.

Climate Change Adaptation Conference at the Science Museum on November 7, 2013

Several organizations are partnering to host the first statewide conference on Climate Change Adaptation, Planning and Practice. It will take place at the Science Museum of Minnesota in downtown St Paul on November 7, 2013. Registration for the all day program is only $50. Sessions will be devoted to city planning, agriculture, transportation, natural resources (including watershed management), and public health.

 

Weekly Weather potpourri

NOAA released a report this week titled "Extreme Events of 2012 From A Climate Perspective." The scientific analysis of extreme climatic events in 2012 reveals that some of the attribution, especially the North American warm temperature signal and the loss of Arctic sea ice can be ascribed to anthropogenic climate change (human induced). The full text of this paper can be found here.

The NOAA National Hurricane Center was issuing warnings this week about Tropical Storm Lorena as it was expected to bring high winds and heavy rains (3-6 inches) to Baja California and SW Mexico into the weekend. It is not expected to reach hurricane status.

NOAA's Storm Prediction Center reported only 34 tornadoes in the past month of August on a nationwide basis. This is less than half of the average number for August and continues to trend of below normal tornado activity this year. The total tornado reports in the USA for 2013 sot far (a little over 700) represents about two-thirds of the historical average number for this time of year.

The National Wildlife Federation released a new report this week about climate change impacts on freshwater fisheries. It is a very interesting report with relevance to Minnesota's freshwater fish populations. You can access it and read more here.

Peru and portions of other South American countries have suffered from severe cold and snow this past week, causing some villages to be isolated, and a good deal of livestock mortality. A state of emergency was declared in nine Peruvian provinces as temperatures plummeted to single digits and below zero F values.

Public statement from the National Weather Service Forecast Office in Chanhassen, MN on Wednesday, September 5, 2013 about a change in the radiosonde program:

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1110 AM CDT WED SEP 04 2013

...CHANHASSEN MINNESOTA NATIONAL WEATHER SERVICE OFFICE BEGINS USING
NEW LMS-6 RADIOSONDES FOR UPPER AIR SOUNDINGS...

SINCE 2005 THE RADIOSONDE REPLACEMENT SYSTEM /RRS/ HAS BEEN USED TO
COLLECT...PROCESS AND DISSEMINATE UPPER AIR DATA USING MODERN GROUND
TRACKING EQUIPMENT AND GPS RADIOSONDES. UNTIL RECENTLY ALL RRS SITES
USED THE MARK IIA GPS RADIOSONDES TO TAKE SOUNDINGS.

IN 2013...THE NATIONAL WEATHER SERVICE /NWS/ SUCCESSFULLY DEPLOYED
AND TESTED THE NEW LOCKHEED MARTIN SIPPICAN LMS-6 GPS RADIOSONDES
AND SUPPORTING RRS SOFTWARE AT SELECTED NWS OFFICES. THE LMS-6 IS
LIGHTER THAN THE MARK IIA AND USES DRY-CELL BATTERIES. IT ALSO
PROVIDES IMPROVED ACCURACY OF THE RH DATA. THE NWS IS NOW READY TO
IMPLEMENT THE LMS-6 RADIOSONDE ACROSS THE UPPER AIR NETWORK. THE
TWIN CITIES NWS OFFICE IN CHANHASSEN MINNESOTA BEGAN UTILIZING THE
LMS-6 RADIOSONDE TODAY...SEPTEMBER 4 2013 AT 12Z.

MPR listener question

In recent years we have experienced some significant flash flooding around the state due to severe thunderstorm rainfalls (Duluth last year for example). What has been the worst storm this year and where was it?

Answer: Right around the summer solstice (June 20-21) a line of thunderstorms moved across the state with heavy rainfall, hail, and damaging winds. The heaviest rainfall caused flash flooding in several central Minnesota communities, including 7.75 inches at Breezy Point (Crow Wing County), 6.69 inches at Lake Park (Becker County), and 5.60 inches at Morris (Stevens County). That remains the heaviest thunderstorm of the year so far.

Twin Cities Almanac for September 6th

The average MSP high temperature for this date is 75 degrees F (plus or minus 10 degrees F standard deviation), while the average low is 57 degrees F (plus or minus 8 degrees F standard deviation).

MSP Local Records for September 6th

MSP weather records for this date include: highest daily maximum temperature of 98 degrees F in 1922; lowest daily maximum temperature of 55 degrees F in 1911; lowest daily minimum temperature is 35 degrees F in 1885; highest daily minimum temperature of 75 F in 1913; and record precipitation of 1.61 inches in 1881; No snow has been recorded on this date.

Average dew point for September 6th is 55 degrees F, with a maximum of 75 degrees F in 1970 and a minimum of 33 degrees F in 1956.

All-time state records for September 6th

The state record high temperature for this date is 105 degrees F at New Ulm (Brown County) in 1922. The state record low temperature for this date is 23 degrees F at Park Rapids (Hubbard County) in 1885. State record precipitation for this date is 8.44 inches at Cloquet (Carlton County) in 1990; and no snow has fallen on this date.

Past Weather Features:

Four consecutive nights with frost ended the growing season in 1885, as over September 4-7 the morning lows ranged from 28 to 35 degrees F around the state. Indian Summer settled in for the second half of the month bringing some daytime highs in the 70s and 80s F.

One of the worst ever September Heat Waves in state history occurred from the 3rd to the 7th of 1922. Daily high temperatures ranged from 90 degrees F to 100 degrees F over 75 percent of the state landscape. The cool spot in the state was Grand Marais with a daytime high of 74 degrees F, while New Ulm sweltered in 105 degrees F. Many Minnesota citizens slept by lakes or on outdoor porches.

Strong thunderstorms over September 5-6, 1990 brought flash flooding to portions of St Louis and Carlton Counties. Rainfall totals ranged from 3 inches to over 8.50 inches, washing out roads and flooding out Jay Cooke State Park, where campers were evacuated. The Cloquet High School was flooded and suffered over $150,000 in damages. Strong winds uprooted trees as well and hail as large as 2 inches in diameter was reported from the Kettle River area.

Word of the Week: Sough (soff)

An old Scottish term, still occasional used it refers to a whisper of wind, perhaps the difference between calm and a measurable amount of wind (2 mph). A sough wind is just barely enough to feel on the face and hands, like a soft touch from Nature.

Outlook

Warm temperatures going into the weekend under mostly sunny skies. Increasing cloudiness on Sunday with a chance for showers and thunderstorms late. Continuing chance for widely scattered showers Monday and early Tuesday in northern areas, spotty elsewhere. Warmer than normal temperatures with a cool off by Tuesday and Wednesday. 
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