I may be having a senior moment here, but wasn't the whole of the UK plastered in blue last night on the BBC forecast with a hard frost promised for all rural locations? Or maybe I got that all wrong and that was the forecast for tonight? Anyway the upshot is that last night only 6 out of 159 stations reported an air frost.

Lowest Minimum Temperature [18-06]
1800 - 0600 UTC on Monday, 22 February 2016
In WMO Block 03

[01] 03065 Cairngorm -7.0 [19.4]
[02] 03041 Aonach Mor. -5.9 [21.4]
[03] 03039 Bealach Na Ba -4.2 [24.4]
[04] 03148 Glen Ogle -2.2 [28.0]
[05] 03031 Loch Glascarnoch -0.2 [31.6]
03063 Aviemore -0.2 [31.6]
[06] 03224 Spadeadam 0.1 [32.2]
03047 Tulloch Bridge 0.1 [32.2]
[07] 03281 Fylingdales 0.2 [32.4]
03911 Lough Sea 0.2 [32.4]
[08] 03904 Castlederg 0.3 [32.5]
03088 Inverbervie 0.3 [32.5]
[09] 03915 Portglenone 0.4 [32.7]
[10] 03230 Redesdale 0.5 [32.9]
03973 Connaught 0.5 [32.9]
[11] 03971 Mullingar 0.6 [33.1]
03002 Baltasound 0.6 [33.1]
03155 Drumalbin 0.6 [33.1]
03075 Wick Airport 0.6 [33.1]
03257 RAF Leeming 0.6 [33.1]
[12] 03080 Aboyne 0.7 [33.3]
[13] 03005 Lerwick 0.8 [33.4]
03044 Altnaharra 0.8 [33.4]
03062 Tain Range 0.8 [33.4]
[14] 03226 Warcop 0.9 [33.6]
[15] 03916 Ballypatrick Forest 1.0 [33.8]
[16] 03979 Ballyhaise, Cavan 1.1 [34.0]
03923 Glenanne 1.1 [34.0]
03068 RAF Lossiemouth 1.1 [34.0]
03162 Eskdalemuir 1.1 [34.0]
[17] 03171 RAF Leuchars 1.2 [34.2]
03917 Belfast 1.2 [34.2]
[18] 03901 Thomastown 1.3 [34.3]
03066 RAF Kinloss 1.3 [34.3]
03026 Stornoway Airport 1.3 [34.3]
[19] 03225 Shap 1.4 [34.5]
[20] 03144 Strathallan 1.6 [34.9]
03261 RAF Dishforth 1.6 [34.9]
03344 Bingley 1.6 [34.9]