LAST DAY IN THE DEEP FREEZE. Fitting that the final day of the year is the last day in this cold snap. Warmth flows in on southwest breezes overnight. We’re double-digits above all week for highs, so break out the tank tops and board shorts. Today we get a little science nerdy and talk about tracking WSI on your own in your area this winter!
(Featured Photo: Field grasses poke through light snow cover on a snowy hike in the chill of Saturday morning. Simonson Photo)
WEATHER (Bismarck Forecast):
Today: Sun 12/31 – Chilly End to 2017. Hi -8, Lo -27, Wind NW@8.
Tomorrow: Mon 1/1 – Doughnut for New Year’s. Hi 0, Lo -21, Wind SW@6.
SOLUNAR (Bismarck Times):
Sunrise: 8:28AM Sunset: 5:05PM
Moonrise: 4:08PM Moonset 6:33AM
Overhead: 11:54PM Underfoot: 11:22AM
Moon Phase: Waxing Gibbous (97% Full)
EDGE HOUR: 4:00-5:00PM – With the relative warm up and a growing full moon, moonrise nearing sunset will boost the odds of a bite in today’s Edge Hour.
ARMCHAIR WSI. Want to get a guess how bad winter is going for wildlife? Create your own Winter Severity Index (WSI). For every day there’s 12 inches of snow or more on the ground, add a point. For every day the temperature touches zero or lower, add a point. The most points for each day is two, though you could add other elements like a bonus point for -20 degrees, or 24 inches of snow cover; it’s a fun semi-scientific process, so make it your own, or tweak it from season to season as you figure out better ways.
Based on the info at the links (which are easily customizable to observations in your neck of the northern plains) this December is sitting at an easy 8 points out of 62 (0 days of 12” or more snow cover, 8 days hitting 0 degrees) for Bismarck. Despite recent cold, that’s a good start on a mild winter. Look the values up at the end of January and February, or tally points daily with your kids or grandkids. Then, at the end of March, add up all the monthly points, using these guideposts to get your best guess as to how things went for wildlife: Mild <50, Moderate 50-90, Difficult 91-140, Severe 141+.
Do some digging on the internet for more ideas, or rankings. States like Wisconsin use higher snow totals for their WSI, and Minnesota has a great annual winter severity map which helps in the establishment of estimates as to wildlife health and deer herd surveys each year based on their particular formula.
Use the links to get an idea of past winter severity indexes in ND if you get curious as to how things are going. Take Dec. 2016 in comparison to this month: 31 days with snow over 12”, 12 days touching 0 for a score of 42. Severe for the month, 42/62.