New Record Low Pressure for Non-Tropical Storm System

[Mike Kovalchick]

Not sure about the 28.05 mentioned in the LOT PNS, but the always reliable wikipedia says 28.28 in the United States for the Jan 78 storm.

The lower readings for that storm ended up being in Canada-for instance Sarnia which is right across the river from Port Huron, MI came in at 28.21.

 

[William Reid]

Should not Tim Samaras' pressure measurement for the Manchester, SD, tornado qualify for "record low pressure for non-tropical storm system" for the U.S.?

Yes, the scales are different, but non-tropical is non-tropical!

http://www.crh.noaa.gov/fsd/?n=tor2003jun24_samaras

William Reid
Westlake Village, CA

 

[Mike Kovalchick]

Should not Tim Samaras' pressure measurement for the Manchester, SD, tornado qualify for "record low pressure for non-tropical storm system" for the U.S.?

Yes, the scales are different, but non-tropical is non-tropical!

http://www.crh.noaa.gov/fsd/?n=tor2003jun24_samaras

William Reid
Westlake Village, CA

Impressive although the numbers don't look to be corrected for elevation as the base pressure is 950mb. I guess if that tornado hit an offical reporting station-it would have to count!

Jeff Masters sheds some light on the whole pressure record discussion topic:
http://www.wunderground.com/blog/JeffMasters/show.html

It mentions that the record in Alaska was 927 mb at Dutch Harbor.

 

[rdale]

Should not Tim Samaras' pressure measurement for the Manchester, SD, tornado qualify for "record low pressure for non-tropical storm system" for the U.S.?

No, because I don't think you can classify a tornado as a "storm system"

 

[William Reid]

No, because I don't think you can classify a tornado as a "storm system"

I suspect that we could find good arguments on both sides for that one.

I realize that this thread is meant to compare and contrast pressure readings for extra-tropical cyclones, but I don't think that we should disregard pressure measurements inside tornadoes if we are considering record low pressures. What is the record low pressure measurement (or reading) for the U.S.? What is the record low pressure measurement for South Dakota? What is the record low pressure for the town of Manchester, SD? Who decides which measurements count and which do not?

If we disregard pressure measurements inside tornadoes, should we disregard measurements beneath all mesocyclones, tornadic and non-tornadic? Should we disregard readings associated with "mesolows"?

With a pressure drop of 100 millibars in the Manchester tornado, we can assume that sea-level pressure there dropped to below 910 mb. (Daily weather maps showed sea-level pressure near 1008 mb in eastern SD on the mornings before and after the event.) If you are the State Climatologist for South Dakota, do you consider this if you are compiling the highest, lowest, strongest, heaviest, etc.??

Just food for thought ---- as Doswell would say, the atmosphere has no consideration for the categories we humans develop.

Bill

 

[rdale]

For the purpose of this discussion - a large scale event that is impacting a good part of the country - there needs to be consideration for the categories. So yes, you would disregard measurements with all mesocyclonea, tornado and non-tornadic because that's not a large-scale event.

If the discussion is "lowest pressure from a meteorological event" then throw the rest in, and put tropical stuff there too. But that's the topic of another thread And I don't know how many tornado pressure readings exist to even work with.

 

[GPhillips]

As you can imagine, this event has prompted extensive research to be done in determining what has been the lowest pressure measured in an extratropical cyclone in the U.S. The latest and greatest (and last?) info on this subject can be found here:

http://www.crh.noaa.gov/dlh/?n=101026_pressurerecords