Here's the sounding for Albermarle which is the nearest available. I'd imagine that the sounding for Blackpool, furtehr west, would have looked even more pronounced.
Code:
03238 Albermarle Observations at 12Z 13 Mar 2006
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PRES HGHT TEMP DWPT RELH MIXR DRCT SKNT THTA THTE THTV
hPa m C C % g/kg deg knot K K K
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1005.0 141 0.6 -3.4 75 2.97 120 8 273.4 281.6 273.9
1002.0 163 0.2 -4.2 72 2.81 127 12 273.2 281.0 273.7
1000.0 177 0.0 -4.5 72 2.75 132 15 273.1 280.8 273.6
993.0 233 -0.6 -4.6 74 2.74 150 25 273.1 280.8 273.6
957.0 527 -3.5 -5.3 87 2.70 164 26 273.1 280.6 273.5
941.0 660 -4.6 -5.6 93 2.69 170 26 273.3 280.8 273.7
939.0 677 -4.7 -5.6 93 2.69 172 26 273.3 280.9 273.8
925.0 795 -4.9 -5.7 94 2.71 185 29 274.3 281.9 274.7
923.0 812 -4.9 -5.6 95 2.74 187 30 274.5 282.2 274.9
917.0 864 0.2 -1.8 87 3.68 195 31 280.2 290.6 280.8
913.0 899 3.6 0.8 82 4.46 195 31 284.0 296.8 284.8
908.0 944 3.6 -0.2 76 4.17 194 31 284.5 296.5 285.2
852.0 1457 0.3 -4.0 73 3.36 190 33 286.3 296.1 286.9
850.0 1476 0.2 -4.1 73 3.33 190 33 286.3 296.1 286.9
845.0 1523 -0.1 -4.2 74 3.33 191 32 286.5 296.3 287.1
829.0 1676 -0.5 -5.0 71 3.18 195 27 287.7 297.1 288.2
813.0 1832 -0.9 -5.9 69 3.04 213 22 288.8 297.9 289.4
811.0 1852 -1.1 -5.9 70 3.05 215 21 288.9 297.9 289.4
782.0 2141 -3.7 -6.0 84 3.14 220 17 289.1 298.4 289.6
779.0 2171 -3.9 -6.1 85 3.13 220 17 289.2 298.5 289.7
721.0 2779 -7.7 -7.8 99 2.96 235 21 291.5 300.4 292.0
701.0 2997 -9.4 -9.4 100 2.68 240 23 291.9 300.1 292.4
700.0 3008 -9.5 -9.5 100 2.67 240 23 291.9 300.0 292.4
Note the layer between 850 hPa (5000 ft) and 920 hPa (abut 2700 ft) that gives the precip a chance to become liquid before plunging into the freezing air below.