Fundamentally Speaking

Upper Midwest Seeing Driest Spring Conditions in Years

Joel Karlin
By  Joel Karlin , DTN Contributing Analyst
Chart by Joel Karlin, DTN Contributing Analyst

This chart shows the three Upper Midwest states of Minnesota, North Dakota and South Dakota that have drawn a lot of attention as to how dry it is in that region of the country.

The end of February Palmer Drought Severity Index (PDSI) is shown on the left-hand axis vs. the percent of the state in D2 to D4 drought category around March 11 plotted on the right-hand axis.

Recall that the monthly PDSI value indicates the severity of a wet or dry spell.

The index generally ranges from -6 to +6, with negative values denoting dry spells and positive values indicating wet spells. There are a few values in the magnitude of +7 or -7.

PDSI values 0 to -.5 = normal; -0.5 to -1.0 = incipient drought; -1.0 to -2.0 = mild drought; -2.0 to -3.0 = moderate drought; -3.0 to -4.0 = severe drought; and greater than -4.0 = extreme drought.

Similar adjectives are attached to positive values of wet spells.

The latest PDSI readings are 1.18 for MN, -1.80 for ND and 2.66 for SD so really only North Dakota by this measure in in drought though it is well above the -2.87 reading at the end of February 2018.

More important is how these readings are much better than the year ago levels of 5.61 for MN, 5.81 for ND and what looks like a record 9.19 for SD.

The point is all of these states were super wet last spring with South Dakota seeing its most saturated soil situation ever so in that regard these PDSI are much more conducive to plantings as already discussed.

Turning to the more recent figures from last week's Drought Monitor Maps and statistics moisture stress is indicated in various levels with D0 considered abnormally dry, D1 indicating moderate drought, D2 indicating severe drought, D3 indicating extreme drought and finally D4 indicating exceptional drought.

Just looking at the combined percent of the state in severe, exceptional or extreme drought D2 to D4 combined area around March 11th shows North Dakota at 80.1% in this category, the highest for this time of year in the 21 years of record keeping with SD at 52.7%, the highest since mid-March 2013 and Minnesota having less than 1% in these three combined categories.

Note that other than in March of 2018 when 8.7% of ND's area was in the D2-D4 stage and 16.2% of SD, since 2013 none of the states had registered any drought whatsoever as this part of the Corn Belt has been well watered for years, actually in some seasons such as 2019 and 2020 to excess.

So there appears to be little to worry about for Minnesota while the Dakotas do have reason for concern with drought already well imbedded in much of the state's land mass prior to the start of the growing season.

We think however that farmers will take dry weather now to get their crops in the ground, especially corn which they were not able to do the past two seasons and hope soil moisture recharges happen after sowings remembering the old saying 'plant in dust, bins will bust'.


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