View Full Version : Lowest QNH?

3rd Dec 2006, 21:58
959 in Stornoway today. Lowest I can remember.....unless you know different?

3rd Dec 2006, 22:04
Down further to 958 this evening I believe.

Captain Airclues
3rd Dec 2006, 22:09
The lowest recorded pressure in the UK was 925.6mb at Ochtertyre, Stirling in 1884. (source..met office website). The aircraft must have had problems setting that on their altimeters!


3rd Dec 2006, 22:26
Some extremes this year! I was surprised to hear a QNH of 941 being stated at Southend during the summer.

3rd Dec 2006, 22:46
Stornoway metars tabulated here,


957mb at 2220 UTC

10/11 January 1993, 'The Braer Storm' likely to have given a much lower QNH at Stornoway as the nearby low was confirmed as min 916mb.

Agaricus bisporus
3rd Dec 2006, 23:41
Well, last time I was in the land of lo pressure (Shetland/ABZ), some time ago admittedly, we had a day whrn the QNH dropped below 950 and some of our (ancient) fleet could not fly as the altimeters would not calibrate below that. On that ocasion those cabs were grounded but there were tales of previous occasions when dispensations had been granted by the CAA to operate with altimeters registering 1000feet high. Can't verify this as fact, maybe someone on Rotorheads would remember if this is correct or my lousy memory or a just another North Sea Myth.

Checked my EFIS kit last week and it went to a scary 750! Some Zebra's @rsehole that would be!

3rd Dec 2006, 23:48
943mb in Longside, north of Aberdeen, mid1980s. The altimeter scale in my Cessna 150 went down to 950 or thereabouts. Circuits seemed normal (to me anyway)

4th Dec 2006, 01:17
Who was setting a QNH of 925.6 in 1884?
No doubt low QNH will be attributed to 'global warming'
I always hoped for a QNH of 1013.25

4th Dec 2006, 01:34
I'm sure that every plane flying in 1884 ;-) with an altimeter had no problem setting the QNH that day.

THE US AIM has a very nice section on how to cope with such problems

4th Dec 2006, 01:36
I always hoped for a QNH of 1013.25
Haa! Thats exactly what I got for my CPL instrument rating one January morning at Stanstead ..Bright sunny no wind and QNH 1013..couldn't believe my luck..took the pressure right off!! Pun intended

Duff beer
4th Dec 2006, 02:17
940 mb

just a few days ago off west Ireland.

we are feeling the results now at manchester.

straight across, gusting 33 kts.


4th Dec 2006, 08:13
Our altimeters only go down to 950 Mb ... at that point we panic and ask Mr Mannering for a QNE (if memory serves - I think it was answer C)

Thridle Op Des
4th Dec 2006, 09:56
Just checked my logbook and I have a note that it was 942 on 20th Dec 1982. We were all talking to Highland Radar working out what to do and settled on us all setting 950 to keep our seperation; up comes Nigel flying a Budgie down from SUM to ABZ an informs us plebs that he can set 600 or something stupid. I remember the day well and the 45 degree drift not being apparent until we saw SHD lighthouse appear in the 10 o'clock while tracking towards it.

Tell the young wippersnappers of our warstories and they get all glazy eyes - dammned impertinance.