Topic: 28 mbar drop in a minute! Settings issue?

[IngemarS]

Hi all,

Last night around 3 am local time as I was sitting developing my new web, I took a short break and checked VWS (14.01p00) and then I saw that a very sudden drop of barm pressure had occured. (Normally in a weather ship that would take at least a couple of hours or more...).

The ASL barom pressure dropped from almost exactly 110 mbar to almost exactly 982 mbar.

Can anyone suggest what might have happened, or if some setting was destroyed (more than an hour earlier I probably had a 5 min break in serail communications that made VWS restart [Settings, Program Settings, Restart Program if Communication lost for 5 min.]. So, I doubt that it is related.

Any ideas?

IngemarS

[IngemarS]

The odd thing is: in the Daily Archive data the barometric values are min 1021.55, max 1022.43 and avg 1021.92.

Is there for some reason some kind of mix of non ASL vs ASL calculations?

IngemarS

 

[ocala]

Not saying for sure but it might have been a gravity wave. One just occurred last week  in SE Texas and southern Louisiana. In that event there was an 8MB drop in one hour.
Was this drop in pressure followed by a very strong wind by chance?
Looking at your graph tells me it may be something else though. What, I don't know.

[IngemarS]

Hi Ocala,

This puzzles me. I went into my MySQL database, which is updated via VWSql, and there I found that the drop was between local time 03:07 and 03:08 AM. So it is not a weather phenomenon...

It is some setting - but I am puzzled. Altitude setting is set to 326 meters which is correct (corresponds to 1070 feet).

Settings/Database settings shows exactly the same as the graph (indicating the same minute for the drop)...

But, Settings/Daily Archive data do not show these low pressures - they show the same as in my previous posting! (around 1020 hPa)

Also, having a look at "nearby" stations 200km ~130 miles report between 1015 and 1030 mbar/hP!

This looks like VWS stopped calculating the VPP raw reading to ASL - makes sense? But, the Broadcast (see attachment) shows 1021 hPa.

I do not get any leads from Settings/Vantage Pro-Weatherlink says barom (in) is 30.17 and when entering the Altitude (ft) 1070 and press Calculate I get Sea-level Correction and Barometer Pressure both to 30.17.

The differences between what is presented in the different graphs 40 hPa...

And, I repeat, this happened suddenly while running 14.01p01 (which had been running at least 7 hours before that happened and it didn't change after installing 14.01p06, and I have done a couple of manual reboots just for test.

Any ideas are REALLY appreciated. 

IngemarS

[IngemarS]

Oops,

The calculated 30.17 which I referred toin my prev posting of course relates to the calculated pressure in inches!

IngemarS

[IngemarS]

The Davis console displays  around 1020 hPa! So why the differences. This will probably destroy my WXSIM forecasts too...

Ingemar

[ocala]

Sorry IngemarS. Don't have a solution for this.
Maybe someone else who uses VWS could help.

[IngemarS]

Thanks for trying Ocala!

Right now, as I got an email about your posting, I HAVE FIXED IT.

I do not know why this happend, or how... but the thing is that the panel was showing Barometer pressure (raw) and the other panel shows SL Barom. Strange indeed!

IngemarS