Climate twins of St. Ignatius, MT

These are the US cities whose 12-month climate pattern most closely matches St. Ignatius's. Each "twin" must be at least 140 miles away to avoid trivial near-neighbor matches. Similarity is computed across all 24 monthly metrics (12 average temperatures + 12 average precipitations), normalized so temperature and precipitation contribute equally.

Side-by-side: St. Ignatius vs its climate twin

Top match: Great Falls, MT

Month	St. Ignatius			Great Falls
	High	Low	Precip	High	Low	Precip
January	36.8°F	22.6°F	0.95 in	36.8°F	17.5°F	0.61 in
February	39.9°F	22.3°F	1.15 in	38.6°F	18.7°F	0.58 in
March	50.6°F	28.0°F	0.94 in	48.2°F	25.2°F	0.63 in
April	59.4°F	33.9°F	1.75 in	58.3°F	33.2°F	1.79 in
May	68.6°F	41.0°F	2.30 in	67.0°F	41.9°F	2.66 in
June	75.1°F	46.7°F	2.63 in	75.4°F	49.6°F	2.74 in
July	86.0°F	52.2°F	0.97 in	85.8°F	55.0°F	1.34 in
August	85.8°F	50.7°F	1.17 in	83.9°F	53.4°F	1.30 in
September	74.8°F	44.1°F	1.51 in	72.6°F	44.7°F	1.39 in
October	59.3°F	34.6°F	1.28 in	59.1°F	35.9°F	1.13 in
November	44.8°F	27.5°F	1.13 in	45.3°F	26.0°F	0.70 in
December	36.5°F	22.5°F	0.94 in	36.7°F	19.8°F	0.56 in

Cities that consider St. Ignatius their climate twin

These US cities have St. Ignatius in their top 3 most-similar list — meaning if you were to move from any of these places, St. Ignatius would feel familiar.

Cascade, MT (ranks St. Ignatius #2)

How this is computed

Each city is represented by a 24-dimensional vector: 12 monthly average temperatures and 12 monthly average precipitations. Each dimension is z-score normalized across the population of US cities, so that temperature variance and precipitation variance contribute proportionally. Distance between cities is Euclidean. We filter out cities within 2° latitude/longitude (~140 miles) so that "twins" mean climatically similar but geographically distinct — not just the neighboring town. Full methodology →