Cool, wet, windy start to April

Cool, wet, windy start to April:

Through the first nine days of the month, most climate stations are reporting an average monthly temperature that is 4°F to 8°F cooler than normal. Sor far temperature extremes for the month have ranged from 69°F at Wells (Faribault County) on the 8th to -6°F at Mahnomen (Mahnomen County) on the 6th. Temperatures are expected to be near normal or a bit warmer than normal for the balance of the month.

Precipitation so far this month has been above normal in most areas of the state, especially southern and eastern counties. Some areas of southeastern Minnesota have reported over 3 inches, but many other areas have reported between 1 inch and 2.50 inches of precipitation so far. Over April 3-4, a few areas of the state reported record daily precipitation amounts. Some of these included: 1.36 inches at Austin, 1.24 inches at Rochester, and 1.03 inches at Caledonia. This wetter-than-normal weather pattern has dropped the area of the Minnesota landscape affected by Moderate to Severe Drought from 34% to 26%. Most of the state is expected to see above normal precipitation for the balance of the month.

Nearly all of the significant snowfalls this month have been in the northern half of the state, where total April snowfall so far has ranged from 6 inches to 18 inches. A few places like Gonvick (Clearwater County), Mahnomen (Mahnomen County), and Thorhult (Beltrami County) have reported over 19 inches of snowfall. On April 4th, Mahnomen reported a daily record snowfall of 12 inches, and Thorhult a daily record snowfall of 10 inches. With warmer and more humid air expected for the balance of April, it appears that there will be little or no snow for the rest of the month.

So far, April has lived up to its reputation as one of the windiest months of the year. Many areas of the state have reported wind gusts of 30 mph or greater on 5 to 8 days, with some gusts exceeding 50 mph. Rochester reported a 60 mph wind gust on Wednesday of this week (April 8). More strong winds are expected with the weather for this coming weekend and into next week, as there is a possibility for strong thunderstorms too.

Weekly Weather Potpourri:

This week’s AGU-EOS Bulletin features a disconcerting article about the removal of the climate science chapter from the Reference Manual on Scientific Evidence that is used by judges for making rulings in scientific cases. This manual has been in play for over 30 years, but Republican Attorney’s General objected to the chapter on climate science and climate change, so it was removed. I am sure that this issue will be revisited in the future as climate science continues to appear in evidence submitted for a variety of court cases.

The Weather Underground reported this week that Hawaii is under another flood watch this week for a tropical disturbance that is bringing heavy rains to all of the islands. This comes on top of record-setting rains and flooding that occurred on many of the islands during the month of March. Those rains and flooding were estimated to have caused a billion dollars in damage.

A recent article published in PLOS Climate (the online non-profit journal for science) highlights the geographic disparities in climate change signals. There no question that measurable climate change is detectable in our wealth of data and official measurements from government agencies, but the magnitude and pace of change is different depending on where you look. For example, this study shows that western areas of the United States are showing more extreme heat, especially in the shoulder seasons, while northern areas are showing a loss of cold during the winter. Similarly, many southwestern areas are showing a decline in annual precipitation, while many northern and eastern areas of the USA are showing increases in average annual precipitation.

MPR listener question:

In last week’s Minnesota WeatherTalk Blog you highlighted some of the remarkable April daily and monthly snowfalls that have been recorded in Minnesota. What about highlighting some of the extremes of precipitation in the month of April?

Answer:

Historical daily precipitation extremes for April in Minnesota include: 7.07 inches of precipitation at Fosston (Polk County) on April 26 of 1912; 6.90 inches at Morris on April 26 of 1954; 6.70 inches at Northfield on April 20 of 1893; and 6.00 inches at Hector (Renville County) on April 13 of 2018. The extreme for total monthly precipitation is 12.60 inches also at Hector (Renville County) in 2018.

Twin Cities Almanac for April 10th:

The average MSP high temperature for this date is 55 degrees F (plus or minus 11 degrees F standard deviation), while the average low is 35 degrees F (plus or minus 8 degrees F standard deviation).

MSP Local Records for April 10th:

MSP records for this date: highest daily maximum temperature of 88 degrees F in 1977; lowest daily maximum temperature of 33 degrees F in 1997; lowest daily minimum temperature of 18 degrees F in 1962; highest daily minimum temperature of 57 degrees F in 1905, and record precipitation of 1.33 inches in 1883. Record snowfall for this date is 6.0 inches in 1891.

Average dew point for April 10th is 29°F; the maximum dew point on this date is 61°F in 2011 and the minimum dew point on this date is 3 degrees F in 1959.

All-time statewide records for April 10th:

The state record high temperature for this date is 92 degrees F at Madison (Lac Qui Parle County) and at Browns Valley (Traverse County) in 1977. The state record low temperature for this date is -13 degrees F at Tower (St Louis County) in 1989. The statewide record for precipitation on this date is 3.14 inches at Harmony (Fillmore County) in 2013. A record 14.0 inches of snow fell at Lynd (Lyon County) on this date in 1913.

Past Weather:

A late season winter storm brought heavy snowfall to southeastern Minnesota over April 9-10 of 1973. Many areas reported 10 inches to 17 inches of snow. Grand Meadow (Mower County) reported 21 inches of snowfall. Many area schools were close for two days.

Record-setting heat prevailed across Minnesota on April 10 of 1977. Many areas reported afternoon temperatures in the 80s F, while Browns Valley (Traverse County) and Madison (Lac Qui Parle County) reported high temperatures of 92°F. Even the overnight low temperatures were record warm, with many readings in the upper 50s F to mid 60s F.

Record-setting cold temperatures prevailed across Minnesota on April 10 of 1989. Most areas reported morning lows in the teens or single digits. Up north where snow cover was still present, climate observers in 7 counties reported subzero low temperatures. At Hallock (Kittson County) the afternoon high temperature only reached 25°F.

Outlook:

Very breezy with a chance for showers, perhaps even thunderstorms over the weekend. It will be humid, with temperatures well above normal for Sunday and Monday. It will remain warmer than normal in southern Minnesota through most of next week, with daily chances for showers and even thunderstorms. In the north, it will cool down closer to normal for much of next week, with chances for rain, especially in the mid-week period.