GREAT LAKES ENVIRONMENTAL RESEARCH LABORATORY, NOAA Climate Data Modernization Project National Weather Service Historical Great Lakes Ice Reports for Winters 1899 - 1970 Site No. 006, Approximate Location: 48.43 N. Latitude, 89.25 W. Longitude Site Name Port Arthur on Lake Superior ---------------------------------------------------------------------------------------------------------- Year Mo Da T1 T2 C1 T1C1 T2C1 C2 T1C2 T2C2 C3 T1C3 T2C3 IMAGE Supplemental Information ---------------------------------------------------------------------------------------------------------- 1910 3 1 -1 -1 SO -1 -1 BV -1 -1 -1 -1 071.TIF LAKE 1910 3 15 -1 -1 OW -1 -1 -1 -1 -1 -1 073.TIF LAKE 1910 3 22 -1 -1 IP -1 -1 -1 -1 -1 -1 074.TIF BAY: TO 8Mi OUT 1910 3 22 -1 -1 BK -1 -1 -1 -1 -1 -1 074.TIF OUTER PORTION OF BAY 1910 3 29 -1 -1 LI -1 -1 -1 -1 -1 -1 075.TIF LAKE 1911 3 21 -1 -1 SO -1 -1 -1 -1 -1 -1 079.TIF ALL RIVERS 1911 3 21 -1 -1 IP -1 -1 -1 -1 -1 -1 079.TIF TO 7Mi OUT 1911 3 28 -1 -1 DI -1 -1 -1 -1 -1 -1 080.TIF LAKE 1911 4 4 -1 -1 SO -1 -1 -1 -1 -1 -1 081.TIF ALL RIVERS 1912 3 12 -1 -1 SO -1 -1 -1 -1 -1 -1 083.TIF TO ISLE ROYALE 1912 3 26 -1 -1 FD -1 -1 -1 -1 -1 -1 085.TIF 1912 4 2 -1 -1 FD -1 -1 NC -1 -1 -1 -1 086.TIF LAKE 1912 4 9 -1 -1 FD -1 -1 NC -1 -1 -1 -1 087.TIF LAKE 1912 4 16 -1 -1 FD -1 -1 -1 -1 -1 -1 088.TIF LAKE 1912 4 23 -1 -1 FD -1 -1 -1 -1 -1 -1 089.TIF LAKE 1913 3 4 30 -1 -1 -1 -1 -1 -1 -1 090.TIF 1/3 OF BAY 1913 3 4 -1 -1 OW -1 -1 -1 -1 -1 -1 090.TIF CHANNEL TO LAKE 1913 3 11 5 -1 -1 -1 -1 -1 -1 -1 091.TIF TO THUNDER CAPE 1913 3 18 5 -1 -1 -1 -1 -1 -1 -1 092.TIF TO THUNDER CAPE 1913 3 25 5 -1 SC -1 -1 -1 -1 -1 -1 093.TIF TO THUNDER CAPE 1913 4 1 -1 -1 BK -1 -1 -1 -1 -1 -1 094.TIF CHANNEL TO 16Mi OUT 1913 4 15 -1 -1 BK -1 -1 -1 -1 -1 -1 096.TIF CHANNEL TO 12Mi OUT 1913 4 22 -1 -1 OW -1 -1 -1 -1 -1 -1 097.TIF A CHANNEL TO 7Mi OUT 1914 3 3 -1 -1 IP -1 -1 -1 -1 -1 -1 098.TIF LAKE: TO ISLE ROYALE 1914 3 3 25 -1 -1 -1 -1 -1 -1 -1 098.TIF AT THE BW 1914 3 10 -1 -1 SO -1 -1 -1 -1 -1 -1 099.TIF BAY 1914 3 10 25 -1 -1 -1 -1 -1 -1 -1 099.TIF AT THE BW 1914 4 7 -1 -1 BK -1 -1 -1 -1 -1 -1 103.TIF CHANNEL TO 5Mi OUT 1914 4 7 -1 -1 OW -1 -1 -1 -1 -1 -1 103.TIF 8Mi OUT 1914 4 14 -1 -1 OW -1 -1 -1 -1 -1 -1 104.TIF 12Mi OUT 1915 3 16 -1 -1 FD -1 -1 -1 -1 -1 -1 107.TIF LAKE 1915 3 23 -1 -1 OW -1 -1 -1 -1 -1 -1 108.TIF BEYOND 14Mi OUT 1915 3 30 -1 -1 FD -1 -1 -1 -1 -1 -1 109.TIF TO 14Mi OUT 1915 4 20 12 14 FD -1 -1 -1 -1 -1 -1 112.TIF BAY 1915 4 20 -1 -1 OW -1 -1 -1 -1 -1 -1 112.TIF CHANNEL TO LAKE 1916 3 14 -1 -1 SO -1 -1 -1 -1 -1 -1 114.TIF TO 10Mi OUT 1916 3 21 12 22 SO -1 -1 SC 12 -1 -1 -1 115.TIF TO 10Mi OUT 1916 4 11 -1 -1 IP -1 -1 -1 -1 -1 -1 118.TIF TO 14Mi OUT 1916 4 18 -1 -1 SO -1 -1 -1 -1 -1 -1 119.TIF TO 10Mi OUT FROM DOCKS 1917 3 13 -1 -1 FD -1 -1 -1 -1 -1 -1 121.TIF LAKE 1917 3 27 41 -1 -1 -1 -1 -1 -1 -1 123.TIF TO BEYOND THE CAPES 1917 4 3 41 -1 NC -1 -1 -1 -1 -1 -1 124.TIF 1917 4 10 41 -1 SO -1 -1 -1 -1 -1 -1 125.TIF 1918 3 19 -1 -1 NC -1 -1 -1 -1 -1 -1 130.TIF LAKE 1918 4 2 -1 -1 FD -1 -1 -1 -1 -1 -1 132.TIF LAKE 1918 4 23 -1 -1 FD -1 -1 -1 -1 -1 -1 135.TIF 1918 4 23 -1 -1 IP -1 -1 -1 -1 -1 -1 135.TIF BAY 1919 3 4 -1 -1 OW -1 -1 -1 -1 -1 -1 136.TIF BAY 1919 3 11 1 2 -1 -1 -1 -1 -1 -1 137.TIF BAY 1919 3 18 -1 -1 LI -1 -1 IN -1 -1 -1 -1 138.TIF BAY 1919 3 21 1 2 LI -1 -1 -1 -1 -1 -1 139.TIF BAY 1920 3 9 18 23 SO -1 -1 -1 -1 -1 -1 140.TIF TO 30Mi OUT 1920 4 6 -1 -1 OW -1 -1 -1 -1 -1 -1 144.TIF SILVER ISLET TO 3Mi OF BW 1921 3 15 -1 -1 OW -1 -1 -1 -1 -1 -1 147.TIF SILVER ISLET 1922 3 21 -1 -1 OW -1 -1 -1 -1 -1 -1 151.TIF CHANNEL TO 8Mi OUT (CUT) 1922 3 28 -1 -1 BK -1 -1 -1 -1 -1 -1 152.TIF 18Mi CHANNEL TO OPEN WATER 1922 4 4 -1 -1 OW -1 -1 -1 -1 -1 -1 153.TIF CHANNEL: THUNDER BAY TO LAKE 1922 4 11 -1 -1 OW -1 -1 -1 -1 -1 -1 154.TIF CHANNEL TO LAKE 1923 3 20 32 -1 -1 -1 -1 -1 -1 -1 157.TIF 1923 4 10 -1 -1 OW -1 -1 -1 -1 -1 -1 160.TIF CHANNEL TO OPEN WATER IN LAKE 1923 4 17 -1 -1 OW -1 -1 -1 -1 -1 -1 161.TIF CHANNEL TO BEYOND THUNDER CAPE 1924 3 4 -1 -1 SO -1 -1 -1 -1 -1 -1 163.TIF TO THUNDER CAPE 1924 3 11 -1 -1 OW -1 -1 -1 -1 -1 -1 164.TIF CHANNEL TO LAKE 1924 4 15 -1 -1 LI -1 -1 -1 -1 -1 -1 169.TIF BAY 1925 3 24 -1 -1 SO -1 -1 -1 -1 -1 -1 172.TIF 1925 3 31 -1 -1 FD -1 -1 RT -1 -1 -1 -1 173.TIF 1925 4 7 -1 -1 SO -1 -1 -1 -1 -1 -1 174.TIF 1925 4 14 -1 -1 OW -1 -1 -1 -1 -1 -1 175.TIF CHANNEL TO LAKE 1926 3 2 22 -1 SO -1 -1 -1 -1 -1 -1 176.TIF TO ISLE ROYALE 1926 3 9 -1 -1 SO -1 -1 -1 -1 -1 -1 177.TIF TO ISLE ROYALE 1926 3 23 -1 -1 SO -1 -1 -1 -1 -1 -1 179.TIF TO ISLE ROYALE 1926 3 30 -1 -1 NC -1 -1 -1 -1 -1 -1 180.TIF 1926 4 13 -1 -1 SO -1 -1 -1 -1 -1 -1 182.TIF TO 14Mi OUT 1926 4 13 -1 -1 FD -1 -1 BK -1 -1 -1 -1 182.TIF BEYOND 14Mi OUT TO OPEN LAKE 1926 4 27 -1 -1 OW -1 -1 -1 -1 -1 -1 184.TIF CHANNEL FROM OPEN LAKE 1927 3 22 -1 -1 FD -1 -1 -1 -1 -1 -1 187.TIF 1927 3 29 -1 -1 FD -1 -1 RT -1 -1 -1 -1 188.TIF 1927 4 5 -1 -1 IP -1 -1 -1 -1 -1 -1 189.TIF 1928 3 13 -1 -1 FD -1 -1 BV -1 -1 -1 -1 191.TIF 1928 3 20 -1 -1 FD -1 -1 BV -1 -1 -1 -1 192.TIF 1928 3 27 -1 -1 FD -1 -1 BV -1 -1 -1 -1 193.TIF 1928 4 3 -1 -1 FD -1 -1 BV -1 -1 -1 -1 194.TIF 1928 4 10 -1 -1 OW -1 -1 -1 -1 -1 -1 195.TIF BEYOND THE BAY 1929 4 2 22 -1 RT -1 -1 -1 -1 -1 -1 200.TIF 1929 4 9 -1 -1 RT -1 -1 -1 -1 -1 -1 201.TIF BAY 1930 3 4 12 30 -1 -1 -1 -1 -1 -1 202.TIF 1930 3 11 28 -1 -1 -1 -1 -1 -1 -1 203.TIF TO 19Mi OUT 1930 3 18 -1 -1 SO -1 -1 -1 -1 -1 -1 204.TIF TO BEYOND THUNDER CAPE 1930 3 25 -1 -1 FD -1 -1 RT -1 -1 -1 -1 205.TIF TO THUNDER CAPE 1930 4 1 24 -1 -1 -1 -1 -1 -1 -1 206.TIF TO WELCOME ISLAND 1930 4 8 -1 -1 RT -1 -1 -1 -1 -1 -1 207.TIF 1931 3 24 -1 -1 DI -1 -1 BK -1 -1 -1 -1 212.TIF LAKE 1932 3 15 14 16 -1 -1 -1 -1 -1 -1 216.TIF OUTSIDE OF HARBOR 1932 3 29 14 -1 -1 -1 -1 -1 -1 -1 525.TIF TO WELCOME ISLANDS 1932 3 29 -1 -1 OW -1 -1 -1 -1 -1 -1 525.TIF BEYOND WELCOME ISLANDS 1932 4 5 14 -1 -1 -1 -1 -1 -1 -1 218.TIF TO 4Mi OUT 1932 4 12 -1 -1 IP -1 -1 -1 -1 -1 -1 219.TIF 1933 3 7 -1 -1 SO -1 -1 BV -1 -1 -1 -1 220.TIF 1933 3 21 -1 -1 IP -1 -1 BV -1 -1 -1 -1 222.TIF 1933 3 28 -1 -1 SO -1 -1 -1 -1 -1 -1 223.TIF TO SEVERAL MILES OUT 1933 4 4 22 -1 CL -1 -1 -1 -1 -1 -1 224.TIF TO SEVERAL MILES OUT 1933 4 11 -1 -1 OW -1 -1 -1 -1 -1 -1 225.TIF CHANNEL TO THE LAKE (CUT) 1934 3 6 -1 -1 SO -1 -1 -1 -1 -1 -1 228.TIF THUNDER BAY 1934 3 20 24 -1 -1 -1 -1 -1 -1 -1 230.TIF THUNDER BAY 1934 4 3 36 -1 CL -1 -1 -1 -1 -1 -1 232.TIF TO 5Mi OUT 1934 4 17 -1 -1 OW -1 -1 -1 -1 -1 -1 234.TIF 6Mi CHANNEL (CUT) 1934 4 24 -1 -1 BK -1 -1 -1 -1 -1 -1 235.TIF TO 12Mi OUT TO OPEN WATER 1935 3 5 23 -1 SO -1 -1 -1 -1 -1 -1 237.TIF 1935 3 12 -1 -1 SO -1 -1 BV -1 -1 -1 -1 238.TIF 1935 3 19 -1 -1 SO -1 -1 -1 -1 -1 -1 239.TIF TO 5Mi OUT 1935 4 16 -1 -1 OW -1 -1 -1 -1 -1 -1 243.TIF CHANNEL TO OPEN WATER 1936 3 17 -1 -1 IP -1 -1 -1 -1 -1 -1 245.TIF TO ISLE ROYALE 1936 3 23 26 -1 -1 -1 -1 -1 -1 -1 246.TIF TO 40Mi OUT 1936 3 30 26 -1 CL -1 -1 -1 -1 -1 -1 247.TIF TO ISLE ROYALE 1936 4 6 -1 -1 SO -1 -1 -1 -1 -1 -1 248.TIF TO ISLE ROYALE 1936 4 13 24 30 SO -1 -1 -1 -1 -1 -1 249.TIF TO 40Mi OUT 1936 4 20 -1 -1 BK -1 -1 -1 -1 -1 -1 250.TIF CHANNEL TO THUNDER CAPE (CUT) 1936 4 27 -1 -1 BK -1 -1 -1 -1 -1 -1 251.TIF CHANNEL TO TROWBRIDGE ISL. (CU 1936 4 27 16 25 -1 -1 -1 -1 -1 -1 251.TIF 1936 5 4 -1 -1 BK -1 -1 -1 -1 -1 -1 252.TIF CHANNEL TO THUNDER CAPE (CUT) 1937 3 8 20 -1 -1 -1 -1 -1 -1 -1 254.TIF TO BEYOND THUNDER CAPE 1937 3 15 -1 -1 IP -1 -1 -1 -1 -1 -1 255.TIF TO 2Mi OUT 1937 3 22 22 -1 -1 -1 -1 -1 -1 -1 256.TIF 1937 3 29 -1 -1 NC -1 -1 -1 -1 -1 -1 257.TIF 1937 4 5 -1 -1 IP -1 -1 -1 -1 -1 -1 258.TIF 1937 4 5 33 -1 -1 -1 -1 -1 -1 -1 258.TIF 9Mi OUT TOWARDS ISLE ROYALE 1937 4 12 22 -1 SO -1 -1 -1 -1 -1 -1 259.TIF TO ISLE ROYALE 1938 3 21 24 36 -1 -1 -1 -1 -1 -1 263.TIF 1938 3 28 -1 -1 OW -1 -1 -1 -1 -1 -1 264.TIF 1939 4 17 30 40 CL -1 -1 -1 -1 -1 -1 274.TIF 1939 4 24 -1 -1 SW -1 -1 -1 -1 -1 -1 275.TIF 20Mi OUT 1940 3 4 30 -1 -1 -1 -1 -1 -1 -1 277.TIF 1940 3 4 -1 -1 IP -1 -1 -1 -1 -1 -1 277.TIF TO ISLE ROYALE 1940 3 11 30 -1 -1 -1 -1 -1 -1 -1 278.TIF 1940 3 11 -1 -1 SO -1 -1 -1 -1 -1 -1 278.TIF TO ISLE ROYALE 1940 3 18 -1 -1 SO -1 -1 -1 -1 -1 -1 279.TIF TO THE WELCOMES 1940 3 24 -1 -1 SO -1 -1 -1 -1 -1 -1 280.TIF TO ISLE ROYALE 1940 4 15 -1 -1 LI -1 -1 DI -1 -1 -1 -1 283.TIF TO ISLE ROYALE 1941 3 10 -1 -1 HF -1 -1 -1 -1 -1 -1 286.TIF SAWYERS BAY: TO WELCOME & PIE 1943 4 5 -1 -1 BK -1 -1 -1 -1 -1 -1 303.TIF OUTER ICE FIELD (CUT) 1943 4 12 -1 -1 SW -1 -1 -1 -1 -1 -1 304.TIF (CUT) 1943 4 26 -1 -1 BK -1 -1 -1 -1 -1 -1 306.TIF 1946 3 25 -1 -1 RT -1 -1 -1 -1 -1 -1 321.TIF BAY 1948 3 15 -1 -1 IP -1 -1 -1 -1 -1 -1 336.TIF TO GRAND MARAIS, MI 1948 3 29 36 -1 BK -1 -1 -1 -1 -1 -1 338.TIF CHANNEL: TO WELCOME ISL. (CUT) 1948 4 12 -1 -1 BK -1 -1 -1 -1 -1 -1 340.TIF CHANNELS TO WELCOME ISL. (CUT) 1949 3 14 -1 -1 OW -1 -1 -1 -1 -1 -1 343.TIF BEYOND 6Mi OUT 1950 2 27 24 -1 -1 -1 -1 -1 -1 -1 349.TIF 1950 3 6 24 26 -1 -1 -1 -1 -1 -1 350.TIF 1950 4 17 -1 -1 SO -1 -1 -1 -1 -1 -1 356.TIF TO ISLE ROYALE 1951 4 16 -1 -1 OW -1 -1 -1 -1 -1 -1 366.TIF 9Mi OUT FROM LIGHTHOUSE 1952 4 14 -1 -1 BK -1 -1 -1 -1 -1 -1 374.TIF (CUT) 1954 3 22 -1 -1 OW -1 -1 -1 -1 -1 -1 384.TIF MISSION CHANNEL 1954 3 22 -1 -1 BK -1 -1 -1 -1 -1 -1 384.TIF (CUT) 1954 4 19 -1 -1 OW -1 -1 -1 -1 -1 -1 388.TIF MAIN LIGHT TO THUNDER CAPE 1955 3 7 18 -1 -1 -1 -1 -1 -1 -1 391.TIF TO 1/4Mi OUT 1955 3 7 -1 -1 SO -1 -1 -1 -1 -1 -1 391.TIF TO THUNDER CAPE 1955 3 7 -1 -1 SO -1 -1 -1 -1 -1 -1 391.TIF TO PIE ISLAND 1955 3 21 -1 -1 BK -1 -1 -1 -1 -1 -1 394.TIF TO 5Mi PAST WELCOME ISL. (CUT) 1955 3 21 -1 -1 SO -1 -1 SC 8 10 -1 -1 394.TIF TO PIE ISLAND 1956 2 27 -1 -1 SO -1 -1 -1 -1 -1 -1 397.TIF TO ISLE ROYALE 1956 3 12 22 26 SO -1 -1 CL -1 -1 -1 -1 401.TIF TO 1/2Mi BEYOND WELCOME ISLAND 1957 2 25 18 24 SC 8 -1 -1 -1 -1 -1 407.TIF MISSION RIVER 1957 3 4 22 -1 SC 5 -1 -1 -1 -1 -1 409.TIF MISSION RIVER 1957 3 11 -1 -1 SO -1 -1 -1 -1 -1 -1 411.TIF TO BEYOND THUNDER CAPE 1958 2 24 -1 -1 SO -1 -1 -1 -1 -1 -1 416.TIF TO THUNDER CAPE 1958 3 17 -1 -1 IP -1 -1 -1 -1 -1 -1 419.TIF TO THUNDER CAPE 1958 3 31 -1 -1 IP -1 -1 -1 -1 -1 -1 421.TIF TO ISLE ROYALE 1958 3 31 16 -1 BK -1 -1 -1 -1 -1 -1 421.TIF CHANNEL: 12Mi OUT (CUT) 1958 4 7 -1 -1 IP -1 -1 PR -1 -1 -1 -1 422.TIF TO ISLE ROYALE 1958 4 14 -1 -1 OW -1 -1 -1 -1 -1 -1 423.TIF TO 1Mi OUTSIDE WELCOME ISLAND 1959 3 16 -1 -1 SO -1 -1 -1 -1 -1 -1 426.TIF TO THUNDER CAPE 1960 3 7 -1 -1 SO -1 -1 -1 -1 -1 -1 434.TIF TO ISLE ROYALE 1960 3 14 -1 -1 RT -1 -1 -1 -1 -1 -1 435.TIF RIVERS 1960 3 21 -1 -1 SO -1 -1 -1 -1 -1 -1 436.TIF TO ISLE ROYALE 1960 4 4 -1 -1 BK -1 -1 -1 -1 -1 -1 438.TIF CHANNEL TO OPEN WATER (CUT) 1960 4 4 18 -1 -1 -1 -1 -1 -1 -1 438.TIF ICE NEAR EDGE OF OPEN WATER 1960 4 11 -1 -1 BK -1 -1 -1 -1 -1 -1 439.TIF NEARLY ALL CHANNELS (CUT) 1961 2 27 12 24 -1 -1 -1 -1 -1 -1 440.TIF JUNCTION: KAM & MISSION RIVERS 1961 3 6 -1 -1 SO -1 -1 -1 -1 -1 -1 441.TIF MISSION & MCKELLAR RIVERS 1961 3 13 -1 -1 FD -1 -1 DI -1 -1 -1 -1 442.TIF LAKE 1961 3 27 18 -1 -1 -1 -1 -1 -1 -1 444.TIF AT RIVER CONFLUENCE 1961 3 27 -1 -1 BK -1 -1 CL -1 -1 -1 -1 444.TIF HARBOR TO SHIPYARDS (CUT) 1961 3 27 -1 -1 FS -1 -1 -1 -1 -1 -1 444.TIF MISSION & MCKELLAR RIVERS 1961 4 3 30 36 BK -1 -1 -1 -1 -1 -1 445.TIF MOUTH OF MISSION RIVER (CUT) 1961 4 10 26 28 SO -1 -1 -1 -1 -1 -1 446.TIF TO WELCOME ISLANDS 1962 2 26 20 30 -1 -1 -1 -1 -1 -1 447.TIF MISSION & MCKELLAR RIVERS 1962 3 5 20 30 -1 -1 -1 -1 -1 -1 448.TIF MISSION & MCKELLAR RIVERS 1962 4 2 -1 -1 RT -1 -1 -1 -1 -1 -1 452.TIF ROCK OF AGES TO MAINLAND 1962 4 16 -1 -1 BK -1 -1 -1 -1 -1 -1 454.TIF CHANNELS TO LAKEHEAD H. (CUT) 1962 4 16 -1 -1 FD -1 -1 BK -1 -1 -1 -1 454.TIF TO WELCOME ISLAND (CUT) 1962 4 23 -1 -1 FD -1 -1 RT -1 -1 -1 -1 455.TIF LAKEHEAD TO PASSAGE ISLAND 1963 4 1 -1 -1 BK -1 -1 -1 -1 -1 -1 461.TIF RIVERS 1963 4 8 -1 -1 RT -1 -1 -1 -1 -1 -1 462.TIF RIVER 1964 3 23 18 21 -1 -1 -1 -1 -1 -1 469.TIF MISSION RIVER 1964 3 23 18 21 -1 -1 -1 -1 -1 -1 469.TIF MCKELLAR RIVER 1965 3 29 20 -1 -1 -1 -1 -1 -1 -1 478.TIF MISSION ENTRANCE 1965 4 5 18 -1 -1 -1 -1 -1 -1 -1 479.TIF KAM RIVER ENTRANCE 1965 4 5 12 -1 -1 -1 -1 -1 -1 -1 479.TIF D BASIN 1965 4 5 20 -1 -1 -1 -1 -1 -1 -1 479.TIF MISSION ENTRANCE 1965 4 19 -1 -1 SO -1 -1 -1 -1 -1 -1 481.TIF TO WELCOME ISLAND 1966 4 4 -1 -1 OW -1 -1 -1 -1 -1 -1 488.TIF SHIPPING LANE TO WELCOME ISL. 1968 4 10 -1 -1 -1 -1 -1 -1 -1 -1 502.TIF PORT OPENING 1968 4 15 -1 -1 OW -1 -1 -1 -1 -1 -1 502.TIF CHANNEL 1969 3 17 -1 -1 SO -1 -1 -1 -1 -1 -1 506.TIF TO ISLE ROYALE ---------------------------------------------------------------------------------------------------------- Ice thickness is in inches, -1 = no thickness reported, see report for ice conditon codes. T1 = ice thickness or part of a range if T2 is present, C1 = primary condtion of ice. T1C1 = thickness of C1 or part of range if T2C1 is presnet. C2, T1C2, T2C2, C3, T1C3, T2C3 are secondary and ternary ice conditon and condition thickness.