Dennis:

1.  The week 52 in the 1996 file is a mistake.  It should read "96" and not "97".  The year should be for the start of the growing season (i.e., week 52 in 1996 is the week with the last Wenesday of February). 

2.  The Modified Palmer Index was not calulated before 1991.  This value however can be computed from the

3. There was a format change in 2001.

4. It is possible for the CMI to reach +13 if torrential rains fell during the week.  Check on the amount of rainfall listed.

Dennis F. Kahlbaum wrote:
Thanks.

FYI: I've found some weird or inconsistent values in the files.

1) The year is sometimes the calendar year, and sometimes the year corresponding to the week.  For example, in the 1996 data, the year for week 52 is given as 97, while the year for week 51 is given as 96; conversely for the 1993 data, the year always stays 93 for all 52 weeks. Needless to say, this inconsistency reeks havoc when trying to sort the data, and match it up with actual week dates.

2) All of the Modified Palmer Indexes are 0.0 for all years 1990 and earlier. Should they be otherwise?

3) The format changed for all 2001 and later data.  Using the FORMAT4.F program gives incorrect values.

4) Crop moisture indexes exceeding +13. Are they real?

Thanks.

--Dennis
 

Tom Heddinghaus wrote:

1. Yes and yes to questions 1 and 2.

 Yes to question 3.  The weeks start on Sunday and end on Saturday.

Tom

Dennis F. Kahlbaum wrote: 

Tom:

Thanks for the link and data.

Three quick questions:

1) Is the Crop Moisture Index given in the data files the Short Term value?

2) Is the Modified Palmer Index given the data files the Long Term value?

3) Do the weeks begin on Sunday, eg, calendar week?   For example, suppose March 1 falls on a Wednesday, does the week start on the last Sunday in February?

Thanks again for your help.

--Dennis


Tom Heddinghaus wrote:

Dennis:

We have weekly Palmer drought and crop moisture data by climate division on our ftp server.

To access the data through your web page browser:

ftp://ftpprd.ncep.noaa.gov/pub/cpc/htdocs/temp2

The files containing data for the growing season are listed (i.e., palmeryy, where yy is the two digit year, i.e., 97). Week one is the week containing the first Wednesday of March for that year.  The last week is the week containing the last Wednesday of February of the following year.

The fortran code to read the data is format4.f for 1997 and after.  Use fortran2.f the read 1996 and before.

Tom Heddinghaus

__

Thomas Heddinghaus, Meteorologist
Climate Operations Branch, CPC, NCEP, NWS, NOAA
E-mail: thomas.heddinghaus@noaa.gov
Phone:  301 - 763 - 8000, ext. 7505

Dennis F. Kahlbaum wrote:

Per our phone conversation, please supply the weekly crop moisture index
data by division for the period of record, if possible.

Thank you!

--Dennis F. Kahlbaum
--University of Michigan
--Staff Meteorologist/Cooperative Weather Observer