IVtinnesota Cold
Big Chill
Minnesota's reputation for bone-chilling w e a t h e r began
soldiers at Fort S n e l l i n g started m e a s u r i n g a n d r e c o r d i n g
when
temperatures
in 1819. In letters h o m e t h e y n o d o u b t s p o k e o f b i t t e r l y c o l d w e a t h e r .
In m o d e r n t i m e s , m e d i a o f t e n cite E m b a r r a s s o r T o w e r as t h e c o l d e s t
places in t h e lower 4 8 o n a particular day.
C o l d Reality
I n t e r n a t i o n a l Falls is t h e c o l d e s t m a j o r N a t i o n a l W e a t h e r S e r v i c e
station outside Alaska. The city has an average annual temperature o f only
37.5 F. O n a v e r a g e t h e t h e r m o m e t e r t h e r e d i p s t o z e r o o r b e l o w 6 4 d a y s
each winter. In Roseau, also near t h e C a n a d i a n border, t h e average J a n u a r y
t e m p e r a t u r e is a l m o s t a d e g r e e b e l o w z e r o ( m i n u s 0 . 7 F ) . T h e T w i n C i t i e s is
t h e coldest m a j o r p o p u l a t i o n center in t h e U n i t e d S t a t e s ( 4 5 . 4 F average
a n n u a l ) , a n d o n e o f t h e coldest in t h e w o r l d .
W h y S o Cold?
M i n n e s o t a ' s relatively h i g h latitude leads to long w i n t e r
n i g h t s a n d o n l y a g l a n c i n g b l o w o f s u n l i g h t d u r i n g w i n t e r d a y s . In
t h e c e n t e r o f t h e c o n t i n e n t , t h e s t a t e is f a r f r o m t h e t e m p e r a t u r e m o d e r a t i n g influence of oceans, a n d has n o natural barriers t o deflect
i n v a s i o n s o f arctic air f r o m t h e n o r t h or n o r t h w e s t .
H o w C o l d C a n It Get?
F e b . 2, 1 9 9 6 , j u s t s o u t h o f T o w e r i n S t . L o u i s
C o u n t y , a volunteer observer for the National W e a t h e r Service recorded
an air t e m p e r a t u r e o f m i n u s 6 0 F — t h e coldest official
measurement
ever m a d e in M i n n e s o t a . Feb. 8, 1899, R o s e a u h a d a n a f t e r n o o n h i g h o f
m i n u s 3 9 F. T h i s r e c o r d - l o w d a i l y h i g h t e m p e r a t u r e o c c u r r e d a m i d o n e
o f t h e l o n g e s t , c o l d e s t spells in M i n n e s o t a ' s c l i m a t e h i s t o r y . F r o m Jan. 2 6
t h r o u g h Feb. 1 2 , 1 8 9 9 , t h e t e m p e r a t u r e in R o s e a u n e v e r r e a c h e d z e r o .
C o m m u n i t i e s s u c h as R o s e a u a n d I n t e r n a t i o n a l Falls c l a i m c o l d w e a t h e r b r a g g i n g r i g h t s because o f their n o r t h e r n latitudes. Rival cold
s p o t s in E m b a r r a s s a n d T o w e r h a v e m o n i t o r i n g s t a t i o n s in l o w - l y i n g
b a s i n s , w h i c h c o l l e c t c o l d , d e n s e air.
W i n d Factor
T h e rate o f heat loss f r o m e x p o s e d skin d e p e n d s o n
t h e c o m b i n e d i m p a c t o f air t e m p e r a t u r e a n d w i n d . A " f e e l s like"
t e m p e r a t u r e c a l c u l a t i o n , c a l l e d wind chill, i n d i c a t e s t h e a t m o s p h e r e ' s
cooling power. O n Jan. 9 a n d 10, 1982, s o m e n o r t h e r n
Minnesota
c o m m u n i t i e s reported air t e m p e r a t u r e s near m i n u s 3 0 F a n d w i n d
s p e e d s a p p r o a c h i n g 4 0 miles per h o u r . T h i s bitter c o m b i n a t i o n
p r o d u c e d w i n d c h i l l s n e a r m i n u s 7 0 F. T h e f o r m u l a i n u s e a t t h a t t i m e
x
I
o
(it w a s c h a n g e d in 2 0 0 1 ) c o m p u t e d t h e w i n d chill t o be a n a s t o u n d i n g
|
m i n u s 1 0 0 F.
o
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Greg Spoden, DNR Waters climatologist
6 4
MINNESOTA CONSERVATION VOLUNTEER
2