Subject: RE: last evening

From: "Douglas, Arthur" <sonora@creighton.edu>

To: Rob Kursinski <kursinsk@atmo.arizona.edu>,

        Bob Maddox <bob@squidinkbooks.com>, <leuthold@atmo.arizona.edu>,

        <twobid@cox.net>, <mullen@atmo.arizona.edu>,

        "Thomas.R.Karl@noaa.gov" <Thomas.R.Karl@noaa.gov>,

        "ppajkck@ku.edu" <ppajkck@ku.edu>

Cc: <kursinski@atmo.arizona.edu>

Thread-Topic: last evening

Thread-Index: AckfUJyKY2mrXzaNS0a4lWLhWGV5bQ==

Date: Thu, 25 Sep 2008 15:52:24 -0500

 

Well I was just throwing that out as a possibility per the last 9 years given SLP in Easter has gone way up in the new PDO mode.  The Hadley circulation most certainly is like with India (though much weaker) with south Indian Ocean SSTs needing to be colder for a stronger high, cross equatorial flow and increased evaporation as the winds approach India.  But...........just one small piece I am sure.

 

 

From: Rob Kursinski

Sent: Thu 9/25/2008 2:12 PM

To: Douglas, Arthur; Rob Kursinski; Bob Maddox; leuthold@atmo.arizona.edu; twobid@cox.net; mullen@atmo.arizona.edu; Thomas.R.Karl@noaa.gov; ppajkck@ku.edu

Cc: kursinski@atmo.arizona.edu

Subject: RE: last evening

 

Thanks.

 

I looked through.  I see you predicted wetter than average for all of the warm months but that was not enough to predict the magnitude of accumulated precip.

 

It looks like the only month that set a precip record this year was August.  June and July are well below the records

 

Hard to believe Antarctica affects our monsoon with flow across the equator but I guess it does.  So a colder Antarctica makes a wetter Mexico.

 

Thanks,

Rob

 

 

 

At 1:55 PM -0500 9/25/08, Douglas, Arthur wrote:

Rob,

 

The graph is a nationwide grid point mean.  One single spot in a given day does not have that much of an impact, but broad events (hurricanes) do have a big impact.  If you look under "Productos" at the SMN website (middle top) and then look under "Precipitacion Mensual y Acumulado" (top of new page) there is a bar graph of the forecast and observed plus climo.  They also have their past monthly data 1941-present on the site under "Productos" and top of that page "Precipitacion Historicas" and click on "Estatisticas."   Every month has been wet since May.  Our forecast was good each month......and consistently in the upper 20% of the wettest years (the class limits for the whole country are very narrow)........but there was no way to forecast these extreme monthly values per our cluster analysis analog forecast technique.  Mexican monthly precipitation has a weak negative correlation..........so persistence definitely does not work!

 

They have not had a particularly dry year since the big El Nino event of 97-98.  Also, the south Pacific high has really increased in intensity over this same period with strong cross equatorial flow towards Mexico.  Antarctica sea ice has actually increased and SSTs north of the ice have been well below normal for some time and this is intensifying the thermal gradient south to north.  All good for the monsoon.

 

Art

 

 

 

From: Rob Kursinski

Sent: Thu 9/25/2008 1:13 PM

To: Douglas, Arthur; Bob Maddox; leuthold@atmo.arizona.edu; twobid@cox.net; mullen@atmo.arizona.edu; Thomas.R.Karl@noaa.gov; ppajkck@ku.edu

Cc: kursinski@atmo.arizona.edu

Subject: RE: last evening

 

Very interesting.

 

In the bar graph, the accumulated June-August rainfall for this year is at least 10% higher than the next highest year in 1981.  Looks like a serious outlier perhaps indicating nonstationary behavior.  Also the wettest in 68 years is because the record is apparently only 68 years long.  This looks like it may be the wettest in quite a bit longer period.

 

Can they get 10% of the June-August precip. in a single event?  If so then the precip could be well above  the other years due to a single event.  The smoothness of the range of precip in the bar graph seems to argue against that.

 

Interstingly, over the past 6 years or so every year has been producing more precip. than the previous year. I wonder how unusual that sequence is as well.  Art, how did your predictions work over this period?  Anything unusual indicating a change relative to past relationships?

 

I've been wondering if our monsoon will intensify as a result of global warming due enhanced land-sea temperature contrast driving stronger monsoonal winds and higher temperatures increasing moisture in the air producing enhanced moisture convergence in the monsoon area.  Perhaps...

 

Thanks for copying me on this

Rob

 

At 12:10 PM -0500 9/25/08, Douglas, Arthur wrote:

You guys should take a look at the Mexican homepage where there are two articles by Javier Espinosa on the extraordinary monsoon they are having.  Now the wettest on record in 68 years.........winning big time!  Daily heavy rainfall events (70mm daily station totals) are well above normal especially in the arid north and by 48% for the entire country.  This despite a Canicula in the south where rainfall totals have been below normal (but in the past few days this too is reversing).

 

Page is <http://smn.cna.gob.mx/>http://smn.cna.gob.mx/

 

Look on the left where the yellow nuevo is flashing for the two reports.

 

In our monthly and seasonal outlooks we forecast a wet monsoon with the south slightly drier than normal.......but the amounts we forecast are not close to those observed.  Forecast, observed and normal can be found under "Productos" center top of home page and then clicking under "Ultimas 24hrs" the "Precipitation mensual y acumulada".

 

Here is the IRI forecasts from May that had above normal rainfall in the far south and normal for the rest of the country:

 

 

 

 

 

 

Art